/* * Copyright 1998, 2000 Marshall Kirk McKusick. All Rights Reserved. * * The soft updates code is derived from the appendix of a University * of Michigan technical report (Gregory R. Ganger and Yale N. Patt, * "Soft Updates: A Solution to the Metadata Update Problem in File * Systems", CSE-TR-254-95, August 1995). * * Further information about soft updates can be obtained from: * * Marshall Kirk McKusick http://www.mckusick.com/softdep/ * 1614 Oxford Street mckusick@mckusick.com * Berkeley, CA 94709-1608 +1-510-843-9542 * USA * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY MARSHALL KIRK MCKUSICK ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL MARSHALL KIRK MCKUSICK BE LIABLE FOR * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)ffs_softdep.c 9.59 (McKusick) 6/21/00 * $FreeBSD$ */ /* * For now we want the safety net that the DIAGNOSTIC and DEBUG flags provide. */ #ifndef DIAGNOSTIC #define DIAGNOSTIC #endif #ifndef DEBUG #define DEBUG #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * These definitions need to be adapted to the system to which * this file is being ported. */ /* * malloc types defined for the softdep system. */ static MALLOC_DEFINE(M_PAGEDEP, "pagedep","File page dependencies"); static MALLOC_DEFINE(M_INODEDEP, "inodedep","Inode dependencies"); static MALLOC_DEFINE(M_NEWBLK, "newblk","New block allocation"); static MALLOC_DEFINE(M_BMSAFEMAP, "bmsafemap","Block or frag allocated from cyl group map"); static MALLOC_DEFINE(M_ALLOCDIRECT, "allocdirect","Block or frag dependency for an inode"); static MALLOC_DEFINE(M_INDIRDEP, "indirdep","Indirect block dependencies"); static MALLOC_DEFINE(M_ALLOCINDIR, "allocindir","Block dependency for an indirect block"); static MALLOC_DEFINE(M_FREEFRAG, "freefrag","Previously used frag for an inode"); static MALLOC_DEFINE(M_FREEBLKS, "freeblks","Blocks freed from an inode"); static MALLOC_DEFINE(M_FREEFILE, "freefile","Inode deallocated"); static MALLOC_DEFINE(M_DIRADD, "diradd","New directory entry"); static MALLOC_DEFINE(M_MKDIR, "mkdir","New directory"); static MALLOC_DEFINE(M_DIRREM, "dirrem","Directory entry deleted"); #define M_SOFTDEP_FLAGS (M_WAITOK | M_USE_RESERVE) #define D_PAGEDEP 0 #define D_INODEDEP 1 #define D_NEWBLK 2 #define D_BMSAFEMAP 3 #define D_ALLOCDIRECT 4 #define D_INDIRDEP 5 #define D_ALLOCINDIR 6 #define D_FREEFRAG 7 #define D_FREEBLKS 8 #define D_FREEFILE 9 #define D_DIRADD 10 #define D_MKDIR 11 #define D_DIRREM 12 #define D_LAST D_DIRREM /* * translate from workitem type to memory type * MUST match the defines above, such that memtype[D_XXX] == M_XXX */ static struct malloc_type *memtype[] = { M_PAGEDEP, M_INODEDEP, M_NEWBLK, M_BMSAFEMAP, M_ALLOCDIRECT, M_INDIRDEP, M_ALLOCINDIR, M_FREEFRAG, M_FREEBLKS, M_FREEFILE, M_DIRADD, M_MKDIR, M_DIRREM }; #define DtoM(type) (memtype[type]) /* * Names of malloc types. */ #define TYPENAME(type) \ ((unsigned)(type) < D_LAST ? memtype[type]->ks_shortdesc : "???") /* * End system adaptaion definitions. */ /* * Internal function prototypes. */ static void softdep_error __P((char *, int)); static void drain_output __P((struct vnode *, int)); static int getdirtybuf __P((struct buf **, int)); static void clear_remove __P((struct proc *)); static void clear_inodedeps __P((struct proc *)); static int flush_pagedep_deps __P((struct vnode *, struct mount *, struct diraddhd *)); static int flush_inodedep_deps __P((struct fs *, ino_t)); static int handle_written_filepage __P((struct pagedep *, struct buf *)); static void diradd_inode_written __P((struct diradd *, struct inodedep *)); static int handle_written_inodeblock __P((struct inodedep *, struct buf *)); static void handle_allocdirect_partdone __P((struct allocdirect *)); static void handle_allocindir_partdone __P((struct allocindir *)); static void initiate_write_filepage __P((struct pagedep *, struct buf *)); static void handle_written_mkdir __P((struct mkdir *, int)); static void initiate_write_inodeblock __P((struct inodedep *, struct buf *)); static void handle_workitem_freefile __P((struct freefile *)); static void handle_workitem_remove __P((struct dirrem *)); static struct dirrem *newdirrem __P((struct buf *, struct inode *, struct inode *, int, struct dirrem **)); static void free_diradd __P((struct diradd *)); static void free_allocindir __P((struct allocindir *, struct inodedep *)); static int indir_trunc __P((struct inode *, ufs_daddr_t, int, ufs_lbn_t, long *)); static void deallocate_dependencies __P((struct buf *, struct inodedep *)); static void free_allocdirect __P((struct allocdirectlst *, struct allocdirect *, int)); static int check_inode_unwritten __P((struct inodedep *)); static int free_inodedep __P((struct inodedep *)); static void handle_workitem_freeblocks __P((struct freeblks *)); static void merge_inode_lists __P((struct inodedep *)); static void setup_allocindir_phase2 __P((struct buf *, struct inode *, struct allocindir *)); static struct allocindir *newallocindir __P((struct inode *, int, ufs_daddr_t, ufs_daddr_t)); static void handle_workitem_freefrag __P((struct freefrag *)); static struct freefrag *newfreefrag __P((struct inode *, ufs_daddr_t, long)); static void allocdirect_merge __P((struct allocdirectlst *, struct allocdirect *, struct allocdirect *)); static struct bmsafemap *bmsafemap_lookup __P((struct buf *)); static int newblk_lookup __P((struct fs *, ufs_daddr_t, int, struct newblk **)); static int inodedep_lookup __P((struct fs *, ino_t, int, struct inodedep **)); static int pagedep_lookup __P((struct inode *, ufs_lbn_t, int, struct pagedep **)); static void pause_timer __P((void *)); static int request_cleanup __P((int, int)); static int process_worklist_item __P((struct mount *, int)); static void add_to_worklist __P((struct worklist *)); /* * Exported softdep operations. */ static void softdep_disk_io_initiation __P((struct buf *)); static void softdep_disk_write_complete __P((struct buf *)); static void softdep_deallocate_dependencies __P((struct buf *)); static void softdep_move_dependencies __P((struct buf *, struct buf *)); static int softdep_count_dependencies __P((struct buf *bp, int)); struct bio_ops bioops = { softdep_disk_io_initiation, /* io_start */ softdep_disk_write_complete, /* io_complete */ softdep_deallocate_dependencies, /* io_deallocate */ softdep_move_dependencies, /* io_movedeps */ softdep_count_dependencies, /* io_countdeps */ }; /* * Locking primitives. * * For a uniprocessor, all we need to do is protect against disk * interrupts. For a multiprocessor, this lock would have to be * a mutex. A single mutex is used throughout this file, though * finer grain locking could be used if contention warranted it. * * For a multiprocessor, the sleep call would accept a lock and * release it after the sleep processing was complete. In a uniprocessor * implementation there is no such interlock, so we simple mark * the places where it needs to be done with the `interlocked' form * of the lock calls. Since the uniprocessor sleep already interlocks * the spl, there is nothing that really needs to be done. */ #ifndef /* NOT */ DEBUG static struct lockit { int lkt_spl; } lk = { 0 }; #define ACQUIRE_LOCK(lk) (lk)->lkt_spl = splbio() #define FREE_LOCK(lk) splx((lk)->lkt_spl) #define ACQUIRE_LOCK_INTERLOCKED(lk) #define FREE_LOCK_INTERLOCKED(lk) #else /* DEBUG */ static struct lockit { int lkt_spl; pid_t lkt_held; } lk = { 0, -1 }; static int lockcnt; static void acquire_lock __P((struct lockit *)); static void free_lock __P((struct lockit *)); static void acquire_lock_interlocked __P((struct lockit *)); static void free_lock_interlocked __P((struct lockit *)); #define ACQUIRE_LOCK(lk) acquire_lock(lk) #define FREE_LOCK(lk) free_lock(lk) #define ACQUIRE_LOCK_INTERLOCKED(lk) acquire_lock_interlocked(lk) #define FREE_LOCK_INTERLOCKED(lk) free_lock_interlocked(lk) static void acquire_lock(lk) struct lockit *lk; { if (lk->lkt_held != -1) { if (lk->lkt_held == CURPROC->p_pid) panic("softdep_lock: locking against myself"); else panic("softdep_lock: lock held by %d", lk->lkt_held); } lk->lkt_spl = splbio(); lk->lkt_held = CURPROC->p_pid; lockcnt++; } static void free_lock(lk) struct lockit *lk; { if (lk->lkt_held == -1) panic("softdep_unlock: lock not held"); lk->lkt_held = -1; splx(lk->lkt_spl); } static void acquire_lock_interlocked(lk) struct lockit *lk; { if (lk->lkt_held != -1) { if (lk->lkt_held == CURPROC->p_pid) panic("softdep_lock_interlocked: locking against self"); else panic("softdep_lock_interlocked: lock held by %d", lk->lkt_held); } lk->lkt_held = CURPROC->p_pid; lockcnt++; } static void free_lock_interlocked(lk) struct lockit *lk; { if (lk->lkt_held == -1) panic("softdep_unlock_interlocked: lock not held"); lk->lkt_held = -1; } #endif /* DEBUG */ /* * Place holder for real semaphores. */ struct sema { int value; pid_t holder; char *name; int prio; int timo; }; static void sema_init __P((struct sema *, char *, int, int)); static int sema_get __P((struct sema *, struct lockit *)); static void sema_release __P((struct sema *)); static void sema_init(semap, name, prio, timo) struct sema *semap; char *name; int prio, timo; { semap->holder = -1; semap->value = 0; semap->name = name; semap->prio = prio; semap->timo = timo; } static int sema_get(semap, interlock) struct sema *semap; struct lockit *interlock; { if (semap->value++ > 0) { if (interlock != NULL) FREE_LOCK_INTERLOCKED(interlock); tsleep((caddr_t)semap, semap->prio, semap->name, semap->timo); if (interlock != NULL) { ACQUIRE_LOCK_INTERLOCKED(interlock); FREE_LOCK(interlock); } return (0); } semap->holder = CURPROC->p_pid; if (interlock != NULL) FREE_LOCK(interlock); return (1); } static void sema_release(semap) struct sema *semap; { if (semap->value <= 0 || semap->holder != CURPROC->p_pid) panic("sema_release: not held"); if (--semap->value > 0) { semap->value = 0; wakeup(semap); } semap->holder = -1; } /* * Worklist queue management. * These routines require that the lock be held. */ #ifndef /* NOT */ DEBUG #define WORKLIST_INSERT(head, item) do { \ (item)->wk_state |= ONWORKLIST; \ LIST_INSERT_HEAD(head, item, wk_list); \ } while (0) #define WORKLIST_REMOVE(item) do { \ (item)->wk_state &= ~ONWORKLIST; \ LIST_REMOVE(item, wk_list); \ } while (0) #define WORKITEM_FREE(item, type) FREE(item, DtoM(type)) #else /* DEBUG */ static void worklist_insert __P((struct workhead *, struct worklist *)); static void worklist_remove __P((struct worklist *)); static void workitem_free __P((struct worklist *, int)); #define WORKLIST_INSERT(head, item) worklist_insert(head, item) #define WORKLIST_REMOVE(item) worklist_remove(item) #define WORKITEM_FREE(item, type) workitem_free((struct worklist *)item, type) static void worklist_insert(head, item) struct workhead *head; struct worklist *item; { if (lk.lkt_held == -1) panic("worklist_insert: lock not held"); if (item->wk_state & ONWORKLIST) panic("worklist_insert: already on list"); item->wk_state |= ONWORKLIST; LIST_INSERT_HEAD(head, item, wk_list); } static void worklist_remove(item) struct worklist *item; { if (lk.lkt_held == -1) panic("worklist_remove: lock not held"); if ((item->wk_state & ONWORKLIST) == 0) panic("worklist_remove: not on list"); item->wk_state &= ~ONWORKLIST; LIST_REMOVE(item, wk_list); } static void workitem_free(item, type) struct worklist *item; int type; { if (item->wk_state & ONWORKLIST) panic("workitem_free: still on list"); if (item->wk_type != type) panic("workitem_free: type mismatch"); FREE(item, DtoM(type)); } #endif /* DEBUG */ /* * Workitem queue management */ static struct workhead softdep_workitem_pending; static int num_on_worklist; /* number of worklist items to be processed */ static int softdep_worklist_busy; /* 1 => trying to do unmount */ static int softdep_worklist_req; /* serialized waiters */ static int max_softdeps; /* maximum number of structs before slowdown */ static int tickdelay = 2; /* number of ticks to pause during slowdown */ static int proc_waiting; /* tracks whether we have a timeout posted */ static int *stat_countp; /* statistic to count in proc_waiting timeout */ static struct callout_handle handle; /* handle on posted proc_waiting timeout */ static struct proc *filesys_syncer; /* proc of filesystem syncer process */ static int req_clear_inodedeps; /* syncer process flush some inodedeps */ #define FLUSH_INODES 1 static int req_clear_remove; /* syncer process flush some freeblks */ #define FLUSH_REMOVE 2 /* * runtime statistics */ static int stat_worklist_push; /* number of worklist cleanups */ static int stat_blk_limit_push; /* number of times block limit neared */ static int stat_ino_limit_push; /* number of times inode limit neared */ static int stat_blk_limit_hit; /* number of times block slowdown imposed */ static int stat_ino_limit_hit; /* number of times inode slowdown imposed */ static int stat_sync_limit_hit; /* number of synchronous slowdowns imposed */ static int stat_indir_blk_ptrs; /* bufs redirtied as indir ptrs not written */ static int stat_inode_bitmap; /* bufs redirtied as inode bitmap not written */ static int stat_direct_blk_ptrs;/* bufs redirtied as direct ptrs not written */ static int stat_dir_entry; /* bufs redirtied as dir entry cannot write */ #ifdef DEBUG #include #include SYSCTL_INT(_debug, OID_AUTO, max_softdeps, CTLFLAG_RW, &max_softdeps, 0, ""); SYSCTL_INT(_debug, OID_AUTO, tickdelay, CTLFLAG_RW, &tickdelay, 0, ""); SYSCTL_INT(_debug, OID_AUTO, worklist_push, CTLFLAG_RW, &stat_worklist_push, 0,""); SYSCTL_INT(_debug, OID_AUTO, blk_limit_push, CTLFLAG_RW, &stat_blk_limit_push, 0,""); SYSCTL_INT(_debug, OID_AUTO, ino_limit_push, CTLFLAG_RW, &stat_ino_limit_push, 0,""); SYSCTL_INT(_debug, OID_AUTO, blk_limit_hit, CTLFLAG_RW, &stat_blk_limit_hit, 0, ""); SYSCTL_INT(_debug, OID_AUTO, ino_limit_hit, CTLFLAG_RW, &stat_ino_limit_hit, 0, ""); SYSCTL_INT(_debug, OID_AUTO, sync_limit_hit, CTLFLAG_RW, &stat_sync_limit_hit, 0, ""); SYSCTL_INT(_debug, OID_AUTO, indir_blk_ptrs, CTLFLAG_RW, &stat_indir_blk_ptrs, 0, ""); SYSCTL_INT(_debug, OID_AUTO, inode_bitmap, CTLFLAG_RW, &stat_inode_bitmap, 0, ""); SYSCTL_INT(_debug, OID_AUTO, direct_blk_ptrs, CTLFLAG_RW, &stat_direct_blk_ptrs, 0, ""); SYSCTL_INT(_debug, OID_AUTO, dir_entry, CTLFLAG_RW, &stat_dir_entry, 0, ""); #endif /* DEBUG */ /* * Add an item to the end of the work queue. * This routine requires that the lock be held. * This is the only routine that adds items to the list. * The following routine is the only one that removes items * and does so in order from first to last. */ static void add_to_worklist(wk) struct worklist *wk; { static struct worklist *worklist_tail; if (wk->wk_state & ONWORKLIST) panic("add_to_worklist: already on list"); wk->wk_state |= ONWORKLIST; if (LIST_FIRST(&softdep_workitem_pending) == NULL) LIST_INSERT_HEAD(&softdep_workitem_pending, wk, wk_list); else LIST_INSERT_AFTER(worklist_tail, wk, wk_list); worklist_tail = wk; num_on_worklist += 1; } /* * Process that runs once per second to handle items in the background queue. * * Note that we ensure that everything is done in the order in which they * appear in the queue. The code below depends on this property to ensure * that blocks of a file are freed before the inode itself is freed. This * ordering ensures that no new triples will be generated * until all the old ones have been purged from the dependency lists. */ int softdep_process_worklist(matchmnt) struct mount *matchmnt; { struct proc *p = CURPROC; int matchcnt, loopcount; long starttime; /* * Record the process identifier of our caller so that we can give * this process preferential treatment in request_cleanup below. */ filesys_syncer = p; matchcnt = 0; /* * There is no danger of having multiple processes run this * code, but we have to single-thread it when softdep_flushfiles() * is in operation to get an accurate count of the number of items * related to its mount point that are in the list. */ if (matchmnt == NULL) { if (softdep_worklist_busy < 0) return(-1); softdep_worklist_busy += 1; } /* * If requested, try removing inode or removal dependencies. */ if (req_clear_inodedeps) { clear_inodedeps(p); req_clear_inodedeps -= 1; wakeup_one(&proc_waiting); } if (req_clear_remove) { clear_remove(p); req_clear_remove -= 1; wakeup_one(&proc_waiting); } loopcount = 1; starttime = time_second; while (num_on_worklist > 0) { matchcnt += process_worklist_item(matchmnt, 0); /* * If a umount operation wants to run the worklist * accurately, abort. */ if (softdep_worklist_req && matchmnt == NULL) { matchcnt = -1; break; } /* * If requested, try removing inode or removal dependencies. */ if (req_clear_inodedeps) { clear_inodedeps(p); req_clear_inodedeps -= 1; wakeup_one(&proc_waiting); } if (req_clear_remove) { clear_remove(p); req_clear_remove -= 1; wakeup_one(&proc_waiting); } /* * We do not generally want to stop for buffer space, but if * we are really being a buffer hog, we will stop and wait. */ if (loopcount++ % 128 == 0) bwillwrite(); /* * Never allow processing to run for more than one * second. Otherwise the other syncer tasks may get * excessively backlogged. */ if (starttime != time_second && matchmnt == NULL) { matchcnt = -1; break; } } if (matchmnt == NULL) { softdep_worklist_busy -= 1; if (softdep_worklist_req && softdep_worklist_busy == 0) wakeup(&softdep_worklist_req); } return (matchcnt); } /* * Process one item on the worklist. */ static int process_worklist_item(matchmnt, flags) struct mount *matchmnt; int flags; { struct worklist *wk; struct dirrem *dirrem; struct mount *mp; struct vnode *vp; int matchcnt = 0; ACQUIRE_LOCK(&lk); /* * Normally we just process each item on the worklist in order. * However, if we are in a situation where we cannot lock any * inodes, we have to skip over any dirrem requests whose * vnodes are resident and locked. */ LIST_FOREACH(wk, &softdep_workitem_pending, wk_list) { if ((flags & LK_NOWAIT) == 0 || wk->wk_type != D_DIRREM) break; dirrem = WK_DIRREM(wk); vp = ufs_ihashlookup(VFSTOUFS(dirrem->dm_mnt)->um_dev, dirrem->dm_oldinum); if (vp == NULL || !VOP_ISLOCKED(vp, CURPROC)) break; } if (wk == 0) return (0); WORKLIST_REMOVE(wk); num_on_worklist -= 1; FREE_LOCK(&lk); switch (wk->wk_type) { case D_DIRREM: /* removal of a directory entry */ mp = WK_DIRREM(wk)->dm_mnt; if (vn_write_suspend_wait(NULL, mp, V_NOWAIT)) panic("%s: dirrem on suspended filesystem", "process_worklist_item"); if (mp == matchmnt) matchcnt += 1; handle_workitem_remove(WK_DIRREM(wk)); break; case D_FREEBLKS: /* releasing blocks and/or fragments from a file */ mp = WK_FREEBLKS(wk)->fb_mnt; if (vn_write_suspend_wait(NULL, mp, V_NOWAIT)) panic("%s: freeblks on suspended filesystem", "process_worklist_item"); if (mp == matchmnt) matchcnt += 1; handle_workitem_freeblocks(WK_FREEBLKS(wk)); break; case D_FREEFRAG: /* releasing a fragment when replaced as a file grows */ mp = WK_FREEFRAG(wk)->ff_mnt; if (vn_write_suspend_wait(NULL, mp, V_NOWAIT)) panic("%s: freefrag on suspended filesystem", "process_worklist_item"); if (mp == matchmnt) matchcnt += 1; handle_workitem_freefrag(WK_FREEFRAG(wk)); break; case D_FREEFILE: /* releasing an inode when its link count drops to 0 */ mp = WK_FREEFILE(wk)->fx_mnt; if (vn_write_suspend_wait(NULL, mp, V_NOWAIT)) panic("%s: freefile on suspended filesystem", "process_worklist_item"); if (mp == matchmnt) matchcnt += 1; handle_workitem_freefile(WK_FREEFILE(wk)); break; default: panic("%s_process_worklist: Unknown type %s", "softdep", TYPENAME(wk->wk_type)); /* NOTREACHED */ } return (matchcnt); } /* * Move dependencies from one buffer to another. */ static void softdep_move_dependencies(oldbp, newbp) struct buf *oldbp; struct buf *newbp; { struct worklist *wk, *wktail; if (LIST_FIRST(&newbp->b_dep) != NULL) panic("softdep_move_dependencies: need merge code"); wktail = 0; ACQUIRE_LOCK(&lk); while ((wk = LIST_FIRST(&oldbp->b_dep)) != NULL) { LIST_REMOVE(wk, wk_list); if (wktail == 0) LIST_INSERT_HEAD(&newbp->b_dep, wk, wk_list); else LIST_INSERT_AFTER(wktail, wk, wk_list); wktail = wk; } FREE_LOCK(&lk); } /* * Purge the work list of all items associated with a particular mount point. */ int softdep_flushworklist(oldmnt, countp, p) struct mount *oldmnt; int *countp; struct proc *p; { struct vnode *devvp; int count, error = 0; /* * Await our turn to clear out the queue, then serialize access. */ while (softdep_worklist_busy) { softdep_worklist_req += 1; tsleep(&softdep_worklist_req, PRIBIO, "softflush", 0); softdep_worklist_req -= 1; } softdep_worklist_busy = -1; /* * Alternately flush the block device associated with the mount * point and process any dependencies that the flushing * creates. We continue until no more worklist dependencies * are found. */ *countp = 0; devvp = VFSTOUFS(oldmnt)->um_devvp; while ((count = softdep_process_worklist(oldmnt)) > 0) { *countp += count; vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p); error = VOP_FSYNC(devvp, p->p_ucred, MNT_WAIT, p); VOP_UNLOCK(devvp, 0, p); if (error) break; } softdep_worklist_busy = 0; if (softdep_worklist_req) wakeup(&softdep_worklist_req); return (error); } /* * Flush all vnodes and worklist items associated with a specified mount point. */ int softdep_flushfiles(oldmnt, flags, p) struct mount *oldmnt; int flags; struct proc *p; { int error, count, loopcnt; /* * Alternately flush the vnodes associated with the mount * point and process any dependencies that the flushing * creates. In theory, this loop can happen at most twice, * but we give it a few extra just to be sure. */ for (loopcnt = 10; loopcnt > 0; loopcnt--) { /* * Do another flush in case any vnodes were brought in * as part of the cleanup operations. */ if ((error = ffs_flushfiles(oldmnt, flags, p)) != 0) break; if ((error = softdep_flushworklist(oldmnt, &count, p)) != 0 || count == 0) break; } /* * If we are unmounting then it is an error to fail. If we * are simply trying to downgrade to read-only, then filesystem * activity can keep us busy forever, so we just fail with EBUSY. */ if (loopcnt == 0) { if (oldmnt->mnt_kern_flag & MNTK_UNMOUNT) panic("softdep_flushfiles: looping"); error = EBUSY; } return (error); } /* * Structure hashing. * * There are three types of structures that can be looked up: * 1) pagedep structures identified by mount point, inode number, * and logical block. * 2) inodedep structures identified by mount point and inode number. * 3) newblk structures identified by mount point and * physical block number. * * The "pagedep" and "inodedep" dependency structures are hashed * separately from the file blocks and inodes to which they correspond. * This separation helps when the in-memory copy of an inode or * file block must be replaced. It also obviates the need to access * an inode or file page when simply updating (or de-allocating) * dependency structures. Lookup of newblk structures is needed to * find newly allocated blocks when trying to associate them with * their allocdirect or allocindir structure. * * The lookup routines optionally create and hash a new instance when * an existing entry is not found. */ #define DEPALLOC 0x0001 /* allocate structure if lookup fails */ /* * Structures and routines associated with pagedep caching. */ LIST_HEAD(pagedep_hashhead, pagedep) *pagedep_hashtbl; u_long pagedep_hash; /* size of hash table - 1 */ #define PAGEDEP_HASH(mp, inum, lbn) \ (&pagedep_hashtbl[((((register_t)(mp)) >> 13) + (inum) + (lbn)) & \ pagedep_hash]) static struct sema pagedep_in_progress; /* * Look up a pagedep. Return 1 if found, 0 if not found. * If not found, allocate if DEPALLOC flag is passed. * Found or allocated entry is returned in pagedeppp. * This routine must be called with splbio interrupts blocked. */ static int pagedep_lookup(ip, lbn, flags, pagedeppp) struct inode *ip; ufs_lbn_t lbn; int flags; struct pagedep **pagedeppp; { struct pagedep *pagedep; struct pagedep_hashhead *pagedephd; struct mount *mp; int i; #ifdef DEBUG if (lk.lkt_held == -1) panic("pagedep_lookup: lock not held"); #endif mp = ITOV(ip)->v_mount; pagedephd = PAGEDEP_HASH(mp, ip->i_number, lbn); top: for (pagedep = LIST_FIRST(pagedephd); pagedep; pagedep = LIST_NEXT(pagedep, pd_hash)) if (ip->i_number == pagedep->pd_ino && lbn == pagedep->pd_lbn && mp == pagedep->pd_mnt) break; if (pagedep) { *pagedeppp = pagedep; return (1); } if ((flags & DEPALLOC) == 0) { *pagedeppp = NULL; return (0); } if (sema_get(&pagedep_in_progress, &lk) == 0) { ACQUIRE_LOCK(&lk); goto top; } MALLOC(pagedep, struct pagedep *, sizeof(struct pagedep), M_PAGEDEP, M_SOFTDEP_FLAGS|M_ZERO); pagedep->pd_list.wk_type = D_PAGEDEP; pagedep->pd_mnt = mp; pagedep->pd_ino = ip->i_number; pagedep->pd_lbn = lbn; LIST_INIT(&pagedep->pd_dirremhd); LIST_INIT(&pagedep->pd_pendinghd); for (i = 0; i < DAHASHSZ; i++) LIST_INIT(&pagedep->pd_diraddhd[i]); ACQUIRE_LOCK(&lk); LIST_INSERT_HEAD(pagedephd, pagedep, pd_hash); sema_release(&pagedep_in_progress); *pagedeppp = pagedep; return (0); } /* * Structures and routines associated with inodedep caching. */ LIST_HEAD(inodedep_hashhead, inodedep) *inodedep_hashtbl; static u_long inodedep_hash; /* size of hash table - 1 */ static long num_inodedep; /* number of inodedep allocated */ #define INODEDEP_HASH(fs, inum) \ (&inodedep_hashtbl[((((register_t)(fs)) >> 13) + (inum)) & inodedep_hash]) static struct sema inodedep_in_progress; /* * Look up a inodedep. Return 1 if found, 0 if not found. * If not found, allocate if DEPALLOC flag is passed. * Found or allocated entry is returned in inodedeppp. * This routine must be called with splbio interrupts blocked. */ static int inodedep_lookup(fs, inum, flags, inodedeppp) struct fs *fs; ino_t inum; int flags; struct inodedep **inodedeppp; { struct inodedep *inodedep; struct inodedep_hashhead *inodedephd; int firsttry; #ifdef DEBUG if (lk.lkt_held == -1) panic("inodedep_lookup: lock not held"); #endif firsttry = 1; inodedephd = INODEDEP_HASH(fs, inum); top: for (inodedep = LIST_FIRST(inodedephd); inodedep; inodedep = LIST_NEXT(inodedep, id_hash)) if (inum == inodedep->id_ino && fs == inodedep->id_fs) break; if (inodedep) { *inodedeppp = inodedep; return (1); } if ((flags & DEPALLOC) == 0) { *inodedeppp = NULL; return (0); } /* * If we are over our limit, try to improve the situation. */ if (num_inodedep > max_softdeps && firsttry && request_cleanup(FLUSH_INODES, 1)) { firsttry = 0; goto top; } if (sema_get(&inodedep_in_progress, &lk) == 0) { ACQUIRE_LOCK(&lk); goto top; } num_inodedep += 1; MALLOC(inodedep, struct inodedep *, sizeof(struct inodedep), M_INODEDEP, M_SOFTDEP_FLAGS); inodedep->id_list.wk_type = D_INODEDEP; inodedep->id_fs = fs; inodedep->id_ino = inum; inodedep->id_state = ALLCOMPLETE; inodedep->id_nlinkdelta = 0; inodedep->id_savedino = NULL; inodedep->id_savedsize = -1; inodedep->id_buf = NULL; LIST_INIT(&inodedep->id_pendinghd); LIST_INIT(&inodedep->id_inowait); LIST_INIT(&inodedep->id_bufwait); TAILQ_INIT(&inodedep->id_inoupdt); TAILQ_INIT(&inodedep->id_newinoupdt); ACQUIRE_LOCK(&lk); LIST_INSERT_HEAD(inodedephd, inodedep, id_hash); sema_release(&inodedep_in_progress); *inodedeppp = inodedep; return (0); } /* * Structures and routines associated with newblk caching. */ LIST_HEAD(newblk_hashhead, newblk) *newblk_hashtbl; u_long newblk_hash; /* size of hash table - 1 */ #define NEWBLK_HASH(fs, inum) \ (&newblk_hashtbl[((((register_t)(fs)) >> 13) + (inum)) & newblk_hash]) static struct sema newblk_in_progress; /* * Look up a newblk. Return 1 if found, 0 if not found. * If not found, allocate if DEPALLOC flag is passed. * Found or allocated entry is returned in newblkpp. */ static int newblk_lookup(fs, newblkno, flags, newblkpp) struct fs *fs; ufs_daddr_t newblkno; int flags; struct newblk **newblkpp; { struct newblk *newblk; struct newblk_hashhead *newblkhd; newblkhd = NEWBLK_HASH(fs, newblkno); top: for (newblk = LIST_FIRST(newblkhd); newblk; newblk = LIST_NEXT(newblk, nb_hash)) if (newblkno == newblk->nb_newblkno && fs == newblk->nb_fs) break; if (newblk) { *newblkpp = newblk; return (1); } if ((flags & DEPALLOC) == 0) { *newblkpp = NULL; return (0); } if (sema_get(&newblk_in_progress, 0) == 0) goto top; MALLOC(newblk, struct newblk *, sizeof(struct newblk), M_NEWBLK, M_SOFTDEP_FLAGS); newblk->nb_state = 0; newblk->nb_fs = fs; newblk->nb_newblkno = newblkno; LIST_INSERT_HEAD(newblkhd, newblk, nb_hash); sema_release(&newblk_in_progress); *newblkpp = newblk; return (0); } /* * Executed during filesystem system initialization before * mounting any file systems. */ void softdep_initialize() { LIST_INIT(&mkdirlisthd); LIST_INIT(&softdep_workitem_pending); max_softdeps = min(desiredvnodes * 8, M_INODEDEP->ks_limit / (2 * sizeof(struct inodedep))); pagedep_hashtbl = hashinit(desiredvnodes / 5, M_PAGEDEP, &pagedep_hash); sema_init(&pagedep_in_progress, "pagedep", PRIBIO, 0); inodedep_hashtbl = hashinit(desiredvnodes, M_INODEDEP, &inodedep_hash); sema_init(&inodedep_in_progress, "inodedep", PRIBIO, 0); newblk_hashtbl = hashinit(64, M_NEWBLK, &newblk_hash); sema_init(&newblk_in_progress, "newblk", PRIBIO, 0); } /* * Called at mount time to notify the dependency code that a * filesystem wishes to use it. */ int softdep_mount(devvp, mp, fs, cred) struct vnode *devvp; struct mount *mp; struct fs *fs; struct ucred *cred; { struct csum cstotal; struct cg *cgp; struct buf *bp; int error, cyl; mp->mnt_flag &= ~MNT_ASYNC; mp->mnt_flag |= MNT_SOFTDEP; /* * When doing soft updates, the counters in the * superblock may have gotten out of sync, so we have * to scan the cylinder groups and recalculate them. */ if (fs->fs_clean != 0) return (0); bzero(&cstotal, sizeof cstotal); for (cyl = 0; cyl < fs->fs_ncg; cyl++) { if ((error = bread(devvp, fsbtodb(fs, cgtod(fs, cyl)), fs->fs_cgsize, cred, &bp)) != 0) { brelse(bp); return (error); } cgp = (struct cg *)bp->b_data; cstotal.cs_nffree += cgp->cg_cs.cs_nffree; cstotal.cs_nbfree += cgp->cg_cs.cs_nbfree; cstotal.cs_nifree += cgp->cg_cs.cs_nifree; cstotal.cs_ndir += cgp->cg_cs.cs_ndir; fs->fs_cs(fs, cyl) = cgp->cg_cs; brelse(bp); } #ifdef DEBUG if (bcmp(&cstotal, &fs->fs_cstotal, sizeof cstotal)) printf("ffs_mountfs: superblock updated for soft updates\n"); #endif bcopy(&cstotal, &fs->fs_cstotal, sizeof cstotal); return (0); } /* * Protecting the freemaps (or bitmaps). * * To eliminate the need to execute fsck before mounting a file system * after a power failure, one must (conservatively) guarantee that the * on-disk copy of the bitmaps never indicate that a live inode or block is * free. So, when a block or inode is allocated, the bitmap should be * updated (on disk) before any new pointers. When a block or inode is * freed, the bitmap should not be updated until all pointers have been * reset. The latter dependency is handled by the delayed de-allocation * approach described below for block and inode de-allocation. The former * dependency is handled by calling the following procedure when a block or * inode is allocated. When an inode is allocated an "inodedep" is created * with its DEPCOMPLETE flag cleared until its bitmap is written to disk. * Each "inodedep" is also inserted into the hash indexing structure so * that any additional link additions can be made dependent on the inode * allocation. * * The ufs file system maintains a number of free block counts (e.g., per * cylinder group, per cylinder and per pair) * in addition to the bitmaps. These counts are used to improve efficiency * during allocation and therefore must be consistent with the bitmaps. * There is no convenient way to guarantee post-crash consistency of these * counts with simple update ordering, for two main reasons: (1) The counts * and bitmaps for a single cylinder group block are not in the same disk * sector. If a disk write is interrupted (e.g., by power failure), one may * be written and the other not. (2) Some of the counts are located in the * superblock rather than the cylinder group block. So, we focus our soft * updates implementation on protecting the bitmaps. When mounting a * filesystem, we recompute the auxiliary counts from the bitmaps. */ /* * Called just after updating the cylinder group block to allocate an inode. */ void softdep_setup_inomapdep(bp, ip, newinum) struct buf *bp; /* buffer for cylgroup block with inode map */ struct inode *ip; /* inode related to allocation */ ino_t newinum; /* new inode number being allocated */ { struct inodedep *inodedep; struct bmsafemap *bmsafemap; /* * Create a dependency for the newly allocated inode. * Panic if it already exists as something is seriously wrong. * Otherwise add it to the dependency list for the buffer holding * the cylinder group map from which it was allocated. */ ACQUIRE_LOCK(&lk); if (inodedep_lookup(ip->i_fs, newinum, DEPALLOC, &inodedep) != 0) panic("softdep_setup_inomapdep: found inode"); inodedep->id_buf = bp; inodedep->id_state &= ~DEPCOMPLETE; bmsafemap = bmsafemap_lookup(bp); LIST_INSERT_HEAD(&bmsafemap->sm_inodedephd, inodedep, id_deps); FREE_LOCK(&lk); } /* * Called just after updating the cylinder group block to * allocate block or fragment. */ void softdep_setup_blkmapdep(bp, fs, newblkno) struct buf *bp; /* buffer for cylgroup block with block map */ struct fs *fs; /* filesystem doing allocation */ ufs_daddr_t newblkno; /* number of newly allocated block */ { struct newblk *newblk; struct bmsafemap *bmsafemap; /* * Create a dependency for the newly allocated block. * Add it to the dependency list for the buffer holding * the cylinder group map from which it was allocated. */ if (newblk_lookup(fs, newblkno, DEPALLOC, &newblk) != 0) panic("softdep_setup_blkmapdep: found block"); ACQUIRE_LOCK(&lk); newblk->nb_bmsafemap = bmsafemap = bmsafemap_lookup(bp); LIST_INSERT_HEAD(&bmsafemap->sm_newblkhd, newblk, nb_deps); FREE_LOCK(&lk); } /* * Find the bmsafemap associated with a cylinder group buffer. * If none exists, create one. The buffer must be locked when * this routine is called and this routine must be called with * splbio interrupts blocked. */ static struct bmsafemap * bmsafemap_lookup(bp) struct buf *bp; { struct bmsafemap *bmsafemap; struct worklist *wk; #ifdef DEBUG if (lk.lkt_held == -1) panic("bmsafemap_lookup: lock not held"); #endif for (wk = LIST_FIRST(&bp->b_dep); wk; wk = LIST_NEXT(wk, wk_list)) if (wk->wk_type == D_BMSAFEMAP) return (WK_BMSAFEMAP(wk)); FREE_LOCK(&lk); MALLOC(bmsafemap, struct bmsafemap *, sizeof(struct bmsafemap), M_BMSAFEMAP, M_SOFTDEP_FLAGS); bmsafemap->sm_list.wk_type = D_BMSAFEMAP; bmsafemap->sm_list.wk_state = 0; bmsafemap->sm_buf = bp; LIST_INIT(&bmsafemap->sm_allocdirecthd); LIST_INIT(&bmsafemap->sm_allocindirhd); LIST_INIT(&bmsafemap->sm_inodedephd); LIST_INIT(&bmsafemap->sm_newblkhd); ACQUIRE_LOCK(&lk); WORKLIST_INSERT(&bp->b_dep, &bmsafemap->sm_list); return (bmsafemap); } /* * Direct block allocation dependencies. * * When a new block is allocated, the corresponding disk locations must be * initialized (with zeros or new data) before the on-disk inode points to * them. Also, the freemap from which the block was allocated must be * updated (on disk) before the inode's pointer. These two dependencies are * independent of each other and are needed for all file blocks and indirect * blocks that are pointed to directly by the inode. Just before the * "in-core" version of the inode is updated with a newly allocated block * number, a procedure (below) is called to setup allocation dependency * structures. These structures are removed when the corresponding * dependencies are satisfied or when the block allocation becomes obsolete * (i.e., the file is deleted, the block is de-allocated, or the block is a * fragment that gets upgraded). All of these cases are handled in * procedures described later. * * When a file extension causes a fragment to be upgraded, either to a larger * fragment or to a full block, the on-disk location may change (if the * previous fragment could not simply be extended). In this case, the old * fragment must be de-allocated, but not until after the inode's pointer has * been updated. In most cases, this is handled by later procedures, which * will construct a "freefrag" structure to be added to the workitem queue * when the inode update is complete (or obsolete). The main exception to * this is when an allocation occurs while a pending allocation dependency * (for the same block pointer) remains. This case is handled in the main * allocation dependency setup procedure by immediately freeing the * unreferenced fragments. */ void softdep_setup_allocdirect(ip, lbn, newblkno, oldblkno, newsize, oldsize, bp) struct inode *ip; /* inode to which block is being added */ ufs_lbn_t lbn; /* block pointer within inode */ ufs_daddr_t newblkno; /* disk block number being added */ ufs_daddr_t oldblkno; /* previous block number, 0 unless frag */ long newsize; /* size of new block */ long oldsize; /* size of new block */ struct buf *bp; /* bp for allocated block */ { struct allocdirect *adp, *oldadp; struct allocdirectlst *adphead; struct bmsafemap *bmsafemap; struct inodedep *inodedep; struct pagedep *pagedep; struct newblk *newblk; MALLOC(adp, struct allocdirect *, sizeof(struct allocdirect), M_ALLOCDIRECT, M_SOFTDEP_FLAGS|M_ZERO); adp->ad_list.wk_type = D_ALLOCDIRECT; adp->ad_lbn = lbn; adp->ad_newblkno = newblkno; adp->ad_oldblkno = oldblkno; adp->ad_newsize = newsize; adp->ad_oldsize = oldsize; adp->ad_state = ATTACHED; if (newblkno == oldblkno) adp->ad_freefrag = NULL; else adp->ad_freefrag = newfreefrag(ip, oldblkno, oldsize); if (newblk_lookup(ip->i_fs, newblkno, 0, &newblk) == 0) panic("softdep_setup_allocdirect: lost block"); ACQUIRE_LOCK(&lk); (void) inodedep_lookup(ip->i_fs, ip->i_number, DEPALLOC, &inodedep); adp->ad_inodedep = inodedep; if (newblk->nb_state == DEPCOMPLETE) { adp->ad_state |= DEPCOMPLETE; adp->ad_buf = NULL; } else { bmsafemap = newblk->nb_bmsafemap; adp->ad_buf = bmsafemap->sm_buf; LIST_REMOVE(newblk, nb_deps); LIST_INSERT_HEAD(&bmsafemap->sm_allocdirecthd, adp, ad_deps); } LIST_REMOVE(newblk, nb_hash); FREE(newblk, M_NEWBLK); WORKLIST_INSERT(&bp->b_dep, &adp->ad_list); if (lbn >= NDADDR) { /* allocating an indirect block */ if (oldblkno != 0) panic("softdep_setup_allocdirect: non-zero indir"); } else { /* * Allocating a direct block. * * If we are allocating a directory block, then we must * allocate an associated pagedep to track additions and * deletions. */ if ((ip->i_mode & IFMT) == IFDIR && pagedep_lookup(ip, lbn, DEPALLOC, &pagedep) == 0) WORKLIST_INSERT(&bp->b_dep, &pagedep->pd_list); } /* * The list of allocdirects must be kept in sorted and ascending * order so that the rollback routines can quickly determine the * first uncommitted block (the size of the file stored on disk * ends at the end of the lowest committed fragment, or if there * are no fragments, at the end of the highest committed block). * Since files generally grow, the typical case is that the new * block is to be added at the end of the list. We speed this * special case by checking against the last allocdirect in the * list before laboriously traversing the list looking for the * insertion point. */ adphead = &inodedep->id_newinoupdt; oldadp = TAILQ_LAST(adphead, allocdirectlst); if (oldadp == NULL || oldadp->ad_lbn <= lbn) { /* insert at end of list */ TAILQ_INSERT_TAIL(adphead, adp, ad_next); if (oldadp != NULL && oldadp->ad_lbn == lbn) allocdirect_merge(adphead, adp, oldadp); FREE_LOCK(&lk); return; } for (oldadp = TAILQ_FIRST(adphead); oldadp; oldadp = TAILQ_NEXT(oldadp, ad_next)) { if (oldadp->ad_lbn >= lbn) break; } if (oldadp == NULL) panic("softdep_setup_allocdirect: lost entry"); /* insert in middle of list */ TAILQ_INSERT_BEFORE(oldadp, adp, ad_next); if (oldadp->ad_lbn == lbn) allocdirect_merge(adphead, adp, oldadp); FREE_LOCK(&lk); } /* * Replace an old allocdirect dependency with a newer one. * This routine must be called with splbio interrupts blocked. */ static void allocdirect_merge(adphead, newadp, oldadp) struct allocdirectlst *adphead; /* head of list holding allocdirects */ struct allocdirect *newadp; /* allocdirect being added */ struct allocdirect *oldadp; /* existing allocdirect being checked */ { struct freefrag *freefrag; #ifdef DEBUG if (lk.lkt_held == -1) panic("allocdirect_merge: lock not held"); #endif if (newadp->ad_oldblkno != oldadp->ad_newblkno || newadp->ad_oldsize != oldadp->ad_newsize || newadp->ad_lbn >= NDADDR) panic("allocdirect_check: old %d != new %d || lbn %ld >= %d", newadp->ad_oldblkno, oldadp->ad_newblkno, newadp->ad_lbn, NDADDR); newadp->ad_oldblkno = oldadp->ad_oldblkno; newadp->ad_oldsize = oldadp->ad_oldsize; /* * If the old dependency had a fragment to free or had never * previously had a block allocated, then the new dependency * can immediately post its freefrag and adopt the old freefrag. * This action is done by swapping the freefrag dependencies. * The new dependency gains the old one's freefrag, and the * old one gets the new one and then immediately puts it on * the worklist when it is freed by free_allocdirect. It is * not possible to do this swap when the old dependency had a * non-zero size but no previous fragment to free. This condition * arises when the new block is an extension of the old block. * Here, the first part of the fragment allocated to the new * dependency is part of the block currently claimed on disk by * the old dependency, so cannot legitimately be freed until the * conditions for the new dependency are fulfilled. */ if (oldadp->ad_freefrag != NULL || oldadp->ad_oldblkno == 0) { freefrag = newadp->ad_freefrag; newadp->ad_freefrag = oldadp->ad_freefrag; oldadp->ad_freefrag = freefrag; } free_allocdirect(adphead, oldadp, 0); } /* * Allocate a new freefrag structure if needed. */ static struct freefrag * newfreefrag(ip, blkno, size) struct inode *ip; ufs_daddr_t blkno; long size; { struct freefrag *freefrag; struct fs *fs; if (blkno == 0) return (NULL); fs = ip->i_fs; if (fragnum(fs, blkno) + numfrags(fs, size) > fs->fs_frag) panic("newfreefrag: frag size"); MALLOC(freefrag, struct freefrag *, sizeof(struct freefrag), M_FREEFRAG, M_SOFTDEP_FLAGS); freefrag->ff_list.wk_type = D_FREEFRAG; freefrag->ff_state = ip->i_uid & ~ONWORKLIST; /* XXX - used below */ freefrag->ff_inum = ip->i_number; freefrag->ff_mnt = ITOV(ip)->v_mount; freefrag->ff_devvp = ip->i_devvp; freefrag->ff_blkno = blkno; freefrag->ff_fragsize = size; return (freefrag); } /* * This workitem de-allocates fragments that were replaced during * file block allocation. */ static void handle_workitem_freefrag(freefrag) struct freefrag *freefrag; { struct inode tip; tip.i_vnode = NULL; tip.i_fs = VFSTOUFS(freefrag->ff_mnt)->um_fs; tip.i_devvp = freefrag->ff_devvp; tip.i_dev = freefrag->ff_devvp->v_rdev; tip.i_number = freefrag->ff_inum; tip.i_uid = freefrag->ff_state & ~ONWORKLIST; /* XXX - set above */ ffs_blkfree(&tip, freefrag->ff_blkno, freefrag->ff_fragsize); FREE(freefrag, M_FREEFRAG); } /* * Indirect block allocation dependencies. * * The same dependencies that exist for a direct block also exist when * a new block is allocated and pointed to by an entry in a block of * indirect pointers. The undo/redo states described above are also * used here. Because an indirect block contains many pointers that * may have dependencies, a second copy of the entire in-memory indirect * block is kept. The buffer cache copy is always completely up-to-date. * The second copy, which is used only as a source for disk writes, * contains only the safe pointers (i.e., those that have no remaining * update dependencies). The second copy is freed when all pointers * are safe. The cache is not allowed to replace indirect blocks with * pending update dependencies. If a buffer containing an indirect * block with dependencies is written, these routines will mark it * dirty again. It can only be successfully written once all the * dependencies are removed. The ffs_fsync routine in conjunction with * softdep_sync_metadata work together to get all the dependencies * removed so that a file can be successfully written to disk. Three * procedures are used when setting up indirect block pointer * dependencies. The division is necessary because of the organization * of the "balloc" routine and because of the distinction between file * pages and file metadata blocks. */ /* * Allocate a new allocindir structure. */ static struct allocindir * newallocindir(ip, ptrno, newblkno, oldblkno) struct inode *ip; /* inode for file being extended */ int ptrno; /* offset of pointer in indirect block */ ufs_daddr_t newblkno; /* disk block number being added */ ufs_daddr_t oldblkno; /* previous block number, 0 if none */ { struct allocindir *aip; MALLOC(aip, struct allocindir *, sizeof(struct allocindir), M_ALLOCINDIR, M_SOFTDEP_FLAGS|M_ZERO); aip->ai_list.wk_type = D_ALLOCINDIR; aip->ai_state = ATTACHED; aip->ai_offset = ptrno; aip->ai_newblkno = newblkno; aip->ai_oldblkno = oldblkno; aip->ai_freefrag = newfreefrag(ip, oldblkno, ip->i_fs->fs_bsize); return (aip); } /* * Called just before setting an indirect block pointer * to a newly allocated file page. */ void softdep_setup_allocindir_page(ip, lbn, bp, ptrno, newblkno, oldblkno, nbp) struct inode *ip; /* inode for file being extended */ ufs_lbn_t lbn; /* allocated block number within file */ struct buf *bp; /* buffer with indirect blk referencing page */ int ptrno; /* offset of pointer in indirect block */ ufs_daddr_t newblkno; /* disk block number being added */ ufs_daddr_t oldblkno; /* previous block number, 0 if none */ struct buf *nbp; /* buffer holding allocated page */ { struct allocindir *aip; struct pagedep *pagedep; aip = newallocindir(ip, ptrno, newblkno, oldblkno); ACQUIRE_LOCK(&lk); /* * If we are allocating a directory page, then we must * allocate an associated pagedep to track additions and * deletions. */ if ((ip->i_mode & IFMT) == IFDIR && pagedep_lookup(ip, lbn, DEPALLOC, &pagedep) == 0) WORKLIST_INSERT(&nbp->b_dep, &pagedep->pd_list); WORKLIST_INSERT(&nbp->b_dep, &aip->ai_list); FREE_LOCK(&lk); setup_allocindir_phase2(bp, ip, aip); } /* * Called just before setting an indirect block pointer to a * newly allocated indirect block. */ void softdep_setup_allocindir_meta(nbp, ip, bp, ptrno, newblkno) struct buf *nbp; /* newly allocated indirect block */ struct inode *ip; /* inode for file being extended */ struct buf *bp; /* indirect block referencing allocated block */ int ptrno; /* offset of pointer in indirect block */ ufs_daddr_t newblkno; /* disk block number being added */ { struct allocindir *aip; aip = newallocindir(ip, ptrno, newblkno, 0); ACQUIRE_LOCK(&lk); WORKLIST_INSERT(&nbp->b_dep, &aip->ai_list); FREE_LOCK(&lk); setup_allocindir_phase2(bp, ip, aip); } /* * Called to finish the allocation of the "aip" allocated * by one of the two routines above. */ static void setup_allocindir_phase2(bp, ip, aip) struct buf *bp; /* in-memory copy of the indirect block */ struct inode *ip; /* inode for file being extended */ struct allocindir *aip; /* allocindir allocated by the above routines */ { struct worklist *wk; struct indirdep *indirdep, *newindirdep; struct bmsafemap *bmsafemap; struct allocindir *oldaip; struct freefrag *freefrag; struct newblk *newblk; if (bp->b_lblkno >= 0) panic("setup_allocindir_phase2: not indir blk"); for (indirdep = NULL, newindirdep = NULL; ; ) { ACQUIRE_LOCK(&lk); for (wk = LIST_FIRST(&bp->b_dep); wk; wk = LIST_NEXT(wk, wk_list)) { if (wk->wk_type != D_INDIRDEP) continue; indirdep = WK_INDIRDEP(wk); break; } if (indirdep == NULL && newindirdep) { indirdep = newindirdep; WORKLIST_INSERT(&bp->b_dep, &indirdep->ir_list); newindirdep = NULL; } FREE_LOCK(&lk); if (indirdep) { if (newblk_lookup(ip->i_fs, aip->ai_newblkno, 0, &newblk) == 0) panic("setup_allocindir: lost block"); ACQUIRE_LOCK(&lk); if (newblk->nb_state == DEPCOMPLETE) { aip->ai_state |= DEPCOMPLETE; aip->ai_buf = NULL; } else { bmsafemap = newblk->nb_bmsafemap; aip->ai_buf = bmsafemap->sm_buf; LIST_REMOVE(newblk, nb_deps); LIST_INSERT_HEAD(&bmsafemap->sm_allocindirhd, aip, ai_deps); } LIST_REMOVE(newblk, nb_hash); FREE(newblk, M_NEWBLK); aip->ai_indirdep = indirdep; /* * Check to see if there is an existing dependency * for this block. If there is, merge the old * dependency into the new one. */ if (aip->ai_oldblkno == 0) oldaip = NULL; else for (oldaip=LIST_FIRST(&indirdep->ir_deplisthd); oldaip; oldaip = LIST_NEXT(oldaip, ai_next)) if (oldaip->ai_offset == aip->ai_offset) break; freefrag = NULL; if (oldaip != NULL) { if (oldaip->ai_newblkno != aip->ai_oldblkno) panic("setup_allocindir_phase2: blkno"); aip->ai_oldblkno = oldaip->ai_oldblkno; freefrag = aip->ai_freefrag; aip->ai_freefrag = oldaip->ai_freefrag; oldaip->ai_freefrag = NULL; free_allocindir(oldaip, NULL); } LIST_INSERT_HEAD(&indirdep->ir_deplisthd, aip, ai_next); ((ufs_daddr_t *)indirdep->ir_savebp->b_data) [aip->ai_offset] = aip->ai_oldblkno; FREE_LOCK(&lk); if (freefrag != NULL) handle_workitem_freefrag(freefrag); } if (newindirdep) { if (indirdep->ir_savebp != NULL) brelse(newindirdep->ir_savebp); WORKITEM_FREE((caddr_t)newindirdep, D_INDIRDEP); } if (indirdep) break; MALLOC(newindirdep, struct indirdep *, sizeof(struct indirdep), M_INDIRDEP, M_SOFTDEP_FLAGS); newindirdep->ir_list.wk_type = D_INDIRDEP; newindirdep->ir_state = ATTACHED; LIST_INIT(&newindirdep->ir_deplisthd); LIST_INIT(&newindirdep->ir_donehd); if (bp->b_blkno == bp->b_lblkno) { VOP_BMAP(bp->b_vp, bp->b_lblkno, NULL, &bp->b_blkno, NULL, NULL); } newindirdep->ir_savebp = getblk(ip->i_devvp, bp->b_blkno, bp->b_bcount, 0, 0); BUF_KERNPROC(newindirdep->ir_savebp); bcopy(bp->b_data, newindirdep->ir_savebp->b_data, bp->b_bcount); } } /* * Block de-allocation dependencies. * * When blocks are de-allocated, the on-disk pointers must be nullified before * the blocks are made available for use by other files. (The true * requirement is that old pointers must be nullified before new on-disk * pointers are set. We chose this slightly more stringent requirement to * reduce complexity.) Our implementation handles this dependency by updating * the inode (or indirect block) appropriately but delaying the actual block * de-allocation (i.e., freemap and free space count manipulation) until * after the updated versions reach stable storage. After the disk is * updated, the blocks can be safely de-allocated whenever it is convenient. * This implementation handles only the common case of reducing a file's * length to zero. Other cases are handled by the conventional synchronous * write approach. * * The ffs implementation with which we worked double-checks * the state of the block pointers and file size as it reduces * a file's length. Some of this code is replicated here in our * soft updates implementation. The freeblks->fb_chkcnt field is * used to transfer a part of this information to the procedure * that eventually de-allocates the blocks. * * This routine should be called from the routine that shortens * a file's length, before the inode's size or block pointers * are modified. It will save the block pointer information for * later release and zero the inode so that the calling routine * can release it. */ void softdep_setup_freeblocks(ip, length) struct inode *ip; /* The inode whose length is to be reduced */ off_t length; /* The new length for the file */ { struct freeblks *freeblks; struct inodedep *inodedep; struct allocdirect *adp; struct vnode *vp; struct buf *bp; struct fs *fs; int i, delay, error; fs = ip->i_fs; if (length != 0) panic("softde_setup_freeblocks: non-zero length"); MALLOC(freeblks, struct freeblks *, sizeof(struct freeblks), M_FREEBLKS, M_SOFTDEP_FLAGS|M_ZERO); freeblks->fb_list.wk_type = D_FREEBLKS; freeblks->fb_uid = ip->i_uid; freeblks->fb_previousinum = ip->i_number; freeblks->fb_devvp = ip->i_devvp; freeblks->fb_mnt = ITOV(ip)->v_mount; freeblks->fb_oldsize = ip->i_size; freeblks->fb_newsize = length; freeblks->fb_chkcnt = ip->i_blocks; for (i = 0; i < NDADDR; i++) { freeblks->fb_dblks[i] = ip->i_db[i]; ip->i_db[i] = 0; } for (i = 0; i < NIADDR; i++) { freeblks->fb_iblks[i] = ip->i_ib[i]; ip->i_ib[i] = 0; } ip->i_blocks = 0; ip->i_size = 0; /* * Push the zero'ed inode to to its disk buffer so that we are free * to delete its dependencies below. Once the dependencies are gone * the buffer can be safely released. */ if ((error = bread(ip->i_devvp, fsbtodb(fs, ino_to_fsba(fs, ip->i_number)), (int)fs->fs_bsize, NOCRED, &bp)) != 0) softdep_error("softdep_setup_freeblocks", error); *((struct dinode *)bp->b_data + ino_to_fsbo(fs, ip->i_number)) = ip->i_din; /* * Find and eliminate any inode dependencies. */ ACQUIRE_LOCK(&lk); (void) inodedep_lookup(fs, ip->i_number, DEPALLOC, &inodedep); if ((inodedep->id_state & IOSTARTED) != 0) panic("softdep_setup_freeblocks: inode busy"); /* * Add the freeblks structure to the list of operations that * must await the zero'ed inode being written to disk. If we * still have a bitmap dependency (delay == 0), then the inode * has never been written to disk, so we can process the * freeblks below once we have deleted the dependencies. */ delay = (inodedep->id_state & DEPCOMPLETE); if (delay) WORKLIST_INSERT(&inodedep->id_bufwait, &freeblks->fb_list); /* * Because the file length has been truncated to zero, any * pending block allocation dependency structures associated * with this inode are obsolete and can simply be de-allocated. * We must first merge the two dependency lists to get rid of * any duplicate freefrag structures, then purge the merged list. * If we still have a bitmap dependency, then the inode has never * been written to disk, so we can free any fragments without delay. */ merge_inode_lists(inodedep); while ((adp = TAILQ_FIRST(&inodedep->id_inoupdt)) != 0) free_allocdirect(&inodedep->id_inoupdt, adp, delay); FREE_LOCK(&lk); bdwrite(bp); /* * We must wait for any I/O in progress to finish so that * all potential buffers on the dirty list will be visible. * Once they are all there, walk the list and get rid of * any dependencies. */ vp = ITOV(ip); ACQUIRE_LOCK(&lk); drain_output(vp, 1); while (getdirtybuf(&TAILQ_FIRST(&vp->v_dirtyblkhd), MNT_WAIT)) { bp = TAILQ_FIRST(&vp->v_dirtyblkhd); (void) inodedep_lookup(fs, ip->i_number, 0, &inodedep); deallocate_dependencies(bp, inodedep); bp->b_flags |= B_INVAL | B_NOCACHE; FREE_LOCK(&lk); brelse(bp); ACQUIRE_LOCK(&lk); } if (inodedep_lookup(fs, ip->i_number, 0, &inodedep) != 0) (void) free_inodedep(inodedep); FREE_LOCK(&lk); /* * If the inode has never been written to disk (delay == 0), * then we can process the freeblks now that we have deleted * the dependencies. */ if (!delay) handle_workitem_freeblocks(freeblks); } /* * Reclaim any dependency structures from a buffer that is about to * be reallocated to a new vnode. The buffer must be locked, thus, * no I/O completion operations can occur while we are manipulating * its associated dependencies. The mutex is held so that other I/O's * associated with related dependencies do not occur. */ static void deallocate_dependencies(bp, inodedep) struct buf *bp; struct inodedep *inodedep; { struct worklist *wk; struct indirdep *indirdep; struct allocindir *aip; struct pagedep *pagedep; struct dirrem *dirrem; struct diradd *dap; int i; while ((wk = LIST_FIRST(&bp->b_dep)) != NULL) { switch (wk->wk_type) { case D_INDIRDEP: indirdep = WK_INDIRDEP(wk); /* * None of the indirect pointers will ever be visible, * so they can simply be tossed. GOINGAWAY ensures * that allocated pointers will be saved in the buffer * cache until they are freed. Note that they will * only be able to be found by their physical address * since the inode mapping the logical address will * be gone. The save buffer used for the safe copy * was allocated in setup_allocindir_phase2 using * the physical address so it could be used for this * purpose. Hence we swap the safe copy with the real * copy, allowing the safe copy to be freed and holding * on to the real copy for later use in indir_trunc. */ if (indirdep->ir_state & GOINGAWAY) panic("deallocate_dependencies: already gone"); indirdep->ir_state |= GOINGAWAY; while ((aip = LIST_FIRST(&indirdep->ir_deplisthd)) != 0) free_allocindir(aip, inodedep); if (bp->b_lblkno >= 0 || bp->b_blkno != indirdep->ir_savebp->b_lblkno) panic("deallocate_dependencies: not indir"); bcopy(bp->b_data, indirdep->ir_savebp->b_data, bp->b_bcount); WORKLIST_REMOVE(wk); WORKLIST_INSERT(&indirdep->ir_savebp->b_dep, wk); continue; case D_PAGEDEP: pagedep = WK_PAGEDEP(wk); /* * None of the directory additions will ever be * visible, so they can simply be tossed. */ for (i = 0; i < DAHASHSZ; i++) while ((dap = LIST_FIRST(&pagedep->pd_diraddhd[i]))) free_diradd(dap); while ((dap = LIST_FIRST(&pagedep->pd_pendinghd)) != 0) free_diradd(dap); /* * Copy any directory remove dependencies to the list * to be processed after the zero'ed inode is written. * If the inode has already been written, then they * can be dumped directly onto the work list. */ for (dirrem = LIST_FIRST(&pagedep->pd_dirremhd); dirrem; dirrem = LIST_NEXT(dirrem, dm_next)) { LIST_REMOVE(dirrem, dm_next); dirrem->dm_dirinum = pagedep->pd_ino; if (inodedep == NULL || (inodedep->id_state & ALLCOMPLETE) == ALLCOMPLETE) add_to_worklist(&dirrem->dm_list); else WORKLIST_INSERT(&inodedep->id_bufwait, &dirrem->dm_list); } WORKLIST_REMOVE(&pagedep->pd_list); LIST_REMOVE(pagedep, pd_hash); WORKITEM_FREE(pagedep, D_PAGEDEP); continue; case D_ALLOCINDIR: free_allocindir(WK_ALLOCINDIR(wk), inodedep); continue; case D_ALLOCDIRECT: case D_INODEDEP: panic("deallocate_dependencies: Unexpected type %s", TYPENAME(wk->wk_type)); /* NOTREACHED */ default: panic("deallocate_dependencies: Unknown type %s", TYPENAME(wk->wk_type)); /* NOTREACHED */ } } } /* * Free an allocdirect. Generate a new freefrag work request if appropriate. * This routine must be called with splbio interrupts blocked. */ static void free_allocdirect(adphead, adp, delay) struct allocdirectlst *adphead; struct allocdirect *adp; int delay; { #ifdef DEBUG if (lk.lkt_held == -1) panic("free_allocdirect: lock not held"); #endif if ((adp->ad_state & DEPCOMPLETE) == 0) LIST_REMOVE(adp, ad_deps); TAILQ_REMOVE(adphead, adp, ad_next); if ((adp->ad_state & COMPLETE) == 0) WORKLIST_REMOVE(&adp->ad_list); if (adp->ad_freefrag != NULL) { if (delay) WORKLIST_INSERT(&adp->ad_inodedep->id_bufwait, &adp->ad_freefrag->ff_list); else add_to_worklist(&adp->ad_freefrag->ff_list); } WORKITEM_FREE(adp, D_ALLOCDIRECT); } /* * Prepare an inode to be freed. The actual free operation is not * done until the zero'ed inode has been written to disk. */ void softdep_freefile(pvp, ino, mode) struct vnode *pvp; ino_t ino; int mode; { struct inode *ip = VTOI(pvp); struct inodedep *inodedep; struct freefile *freefile; /* * This sets up the inode de-allocation dependency. */ MALLOC(freefile, struct freefile *, sizeof(struct freefile), M_FREEFILE, M_SOFTDEP_FLAGS); freefile->fx_list.wk_type = D_FREEFILE; freefile->fx_list.wk_state = 0; freefile->fx_mode = mode; freefile->fx_oldinum = ino; freefile->fx_devvp = ip->i_devvp; freefile->fx_mnt = ITOV(ip)->v_mount; /* * If the inodedep does not exist, then the zero'ed inode has * been written to disk. If the allocated inode has never been * written to disk, then the on-disk inode is zero'ed. In either * case we can free the file immediately. */ ACQUIRE_LOCK(&lk); if (inodedep_lookup(ip->i_fs, ino, 0, &inodedep) == 0 || check_inode_unwritten(inodedep)) { FREE_LOCK(&lk); handle_workitem_freefile(freefile); return; } WORKLIST_INSERT(&inodedep->id_inowait, &freefile->fx_list); FREE_LOCK(&lk); } /* * Check to see if an inode has never been written to disk. If * so free the inodedep and return success, otherwise return failure. * This routine must be called with splbio interrupts blocked. * * If we still have a bitmap dependency, then the inode has never * been written to disk. Drop the dependency as it is no longer * necessary since the inode is being deallocated. We set the * ALLCOMPLETE flags since the bitmap now properly shows that the * inode is not allocated. Even if the inode is actively being * written, it has been rolled back to its zero'ed state, so we * are ensured that a zero inode is what is on the disk. For short * lived files, this change will usually result in removing all the * dependencies from the inode so that it can be freed immediately. */ static int check_inode_unwritten(inodedep) struct inodedep *inodedep; { if ((inodedep->id_state & DEPCOMPLETE) != 0 || LIST_FIRST(&inodedep->id_pendinghd) != NULL || LIST_FIRST(&inodedep->id_bufwait) != NULL || LIST_FIRST(&inodedep->id_inowait) != NULL || TAILQ_FIRST(&inodedep->id_inoupdt) != NULL || TAILQ_FIRST(&inodedep->id_newinoupdt) != NULL || inodedep->id_nlinkdelta != 0) return (0); inodedep->id_state |= ALLCOMPLETE; LIST_REMOVE(inodedep, id_deps); inodedep->id_buf = NULL; if (inodedep->id_state & ONWORKLIST) WORKLIST_REMOVE(&inodedep->id_list); if (inodedep->id_savedino != NULL) { FREE(inodedep->id_savedino, M_INODEDEP); inodedep->id_savedino = NULL; } if (free_inodedep(inodedep) == 0) panic("check_inode_unwritten: busy inode"); return (1); } /* * Try to free an inodedep structure. Return 1 if it could be freed. */ static int free_inodedep(inodedep) struct inodedep *inodedep; { if ((inodedep->id_state & ONWORKLIST) != 0 || (inodedep->id_state & ALLCOMPLETE) != ALLCOMPLETE || LIST_FIRST(&inodedep->id_pendinghd) != NULL || LIST_FIRST(&inodedep->id_bufwait) != NULL || LIST_FIRST(&inodedep->id_inowait) != NULL || TAILQ_FIRST(&inodedep->id_inoupdt) != NULL || TAILQ_FIRST(&inodedep->id_newinoupdt) != NULL || inodedep->id_nlinkdelta != 0 || inodedep->id_savedino != NULL) return (0); LIST_REMOVE(inodedep, id_hash); WORKITEM_FREE(inodedep, D_INODEDEP); num_inodedep -= 1; return (1); } /* * This workitem routine performs the block de-allocation. * The workitem is added to the pending list after the updated * inode block has been written to disk. As mentioned above, * checks regarding the number of blocks de-allocated (compared * to the number of blocks allocated for the file) are also * performed in this function. */ static void handle_workitem_freeblocks(freeblks) struct freeblks *freeblks; { struct inode tip; ufs_daddr_t bn; struct fs *fs; int i, level, bsize; long nblocks, blocksreleased = 0; int error, allerror = 0; ufs_lbn_t baselbns[NIADDR], tmpval; tip.i_fs = fs = VFSTOUFS(freeblks->fb_mnt)->um_fs; tip.i_number = freeblks->fb_previousinum; tip.i_devvp = freeblks->fb_devvp; tip.i_dev = freeblks->fb_devvp->v_rdev; tip.i_size = freeblks->fb_oldsize; tip.i_uid = freeblks->fb_uid; tip.i_vnode = NULL; tmpval = 1; baselbns[0] = NDADDR; for (i = 1; i < NIADDR; i++) { tmpval *= NINDIR(fs); baselbns[i] = baselbns[i - 1] + tmpval; } nblocks = btodb(fs->fs_bsize); blocksreleased = 0; /* * Indirect blocks first. */ for (level = (NIADDR - 1); level >= 0; level--) { if ((bn = freeblks->fb_iblks[level]) == 0) continue; if ((error = indir_trunc(&tip, fsbtodb(fs, bn), level, baselbns[level], &blocksreleased)) == 0) allerror = error; ffs_blkfree(&tip, bn, fs->fs_bsize); blocksreleased += nblocks; } /* * All direct blocks or frags. */ for (i = (NDADDR - 1); i >= 0; i--) { if ((bn = freeblks->fb_dblks[i]) == 0) continue; bsize = blksize(fs, &tip, i); ffs_blkfree(&tip, bn, bsize); blocksreleased += btodb(bsize); } #ifdef DIAGNOSTIC if (freeblks->fb_chkcnt != blocksreleased) printf("handle_workitem_freeblocks: block count"); if (allerror) softdep_error("handle_workitem_freeblks", allerror); #endif /* DIAGNOSTIC */ WORKITEM_FREE(freeblks, D_FREEBLKS); } /* * Release blocks associated with the inode ip and stored in the indirect * block dbn. If level is greater than SINGLE, the block is an indirect block * and recursive calls to indirtrunc must be used to cleanse other indirect * blocks. */ static int indir_trunc(ip, dbn, level, lbn, countp) struct inode *ip; ufs_daddr_t dbn; int level; ufs_lbn_t lbn; long *countp; { struct buf *bp; ufs_daddr_t *bap; ufs_daddr_t nb; struct fs *fs; struct worklist *wk; struct indirdep *indirdep; int i, lbnadd, nblocks; int error, allerror = 0; fs = ip->i_fs; lbnadd = 1; for (i = level; i > 0; i--) lbnadd *= NINDIR(fs); /* * Get buffer of block pointers to be freed. This routine is not * called until the zero'ed inode has been written, so it is safe * to free blocks as they are encountered. Because the inode has * been zero'ed, calls to bmap on these blocks will fail. So, we * have to use the on-disk address and the block device for the * filesystem to look them up. If the file was deleted before its * indirect blocks were all written to disk, the routine that set * us up (deallocate_dependencies) will have arranged to leave * a complete copy of the indirect block in memory for our use. * Otherwise we have to read the blocks in from the disk. */ ACQUIRE_LOCK(&lk); if ((bp = incore(ip->i_devvp, dbn)) != NULL && (wk = LIST_FIRST(&bp->b_dep)) != NULL) { if (wk->wk_type != D_INDIRDEP || (indirdep = WK_INDIRDEP(wk))->ir_savebp != bp || (indirdep->ir_state & GOINGAWAY) == 0) panic("indir_trunc: lost indirdep"); WORKLIST_REMOVE(wk); WORKITEM_FREE(indirdep, D_INDIRDEP); if (LIST_FIRST(&bp->b_dep) != NULL) panic("indir_trunc: dangling dep"); FREE_LOCK(&lk); } else { FREE_LOCK(&lk); error = bread(ip->i_devvp, dbn, (int)fs->fs_bsize, NOCRED, &bp); if (error) return (error); } /* * Recursively free indirect blocks. */ bap = (ufs_daddr_t *)bp->b_data; nblocks = btodb(fs->fs_bsize); for (i = NINDIR(fs) - 1; i >= 0; i--) { if ((nb = bap[i]) == 0) continue; if (level != 0) { if ((error = indir_trunc(ip, fsbtodb(fs, nb), level - 1, lbn + (i * lbnadd), countp)) != 0) allerror = error; } ffs_blkfree(ip, nb, fs->fs_bsize); *countp += nblocks; } bp->b_flags |= B_INVAL | B_NOCACHE; brelse(bp); return (allerror); } /* * Free an allocindir. * This routine must be called with splbio interrupts blocked. */ static void free_allocindir(aip, inodedep) struct allocindir *aip; struct inodedep *inodedep; { struct freefrag *freefrag; #ifdef DEBUG if (lk.lkt_held == -1) panic("free_allocindir: lock not held"); #endif if ((aip->ai_state & DEPCOMPLETE) == 0) LIST_REMOVE(aip, ai_deps); if (aip->ai_state & ONWORKLIST) WORKLIST_REMOVE(&aip->ai_list); LIST_REMOVE(aip, ai_next); if ((freefrag = aip->ai_freefrag) != NULL) { if (inodedep == NULL) add_to_worklist(&freefrag->ff_list); else WORKLIST_INSERT(&inodedep->id_bufwait, &freefrag->ff_list); } WORKITEM_FREE(aip, D_ALLOCINDIR); } /* * Directory entry addition dependencies. * * When adding a new directory entry, the inode (with its incremented link * count) must be written to disk before the directory entry's pointer to it. * Also, if the inode is newly allocated, the corresponding freemap must be * updated (on disk) before the directory entry's pointer. These requirements * are met via undo/redo on the directory entry's pointer, which consists * simply of the inode number. * * As directory entries are added and deleted, the free space within a * directory block can become fragmented. The ufs file system will compact * a fragmented directory block to make space for a new entry. When this * occurs, the offsets of previously added entries change. Any "diradd" * dependency structures corresponding to these entries must be updated with * the new offsets. */ /* * This routine is called after the in-memory inode's link * count has been incremented, but before the directory entry's * pointer to the inode has been set. */ void softdep_setup_directory_add(bp, dp, diroffset, newinum, newdirbp) struct buf *bp; /* buffer containing directory block */ struct inode *dp; /* inode for directory */ off_t diroffset; /* offset of new entry in directory */ long newinum; /* inode referenced by new directory entry */ struct buf *newdirbp; /* non-NULL => contents of new mkdir */ { int offset; /* offset of new entry within directory block */ ufs_lbn_t lbn; /* block in directory containing new entry */ struct fs *fs; struct diradd *dap; struct pagedep *pagedep; struct inodedep *inodedep; struct mkdir *mkdir1, *mkdir2; /* * Whiteouts have no dependencies. */ if (newinum == WINO) { if (newdirbp != NULL) bdwrite(newdirbp); return; } fs = dp->i_fs; lbn = lblkno(fs, diroffset); offset = blkoff(fs, diroffset); MALLOC(dap, struct diradd *, sizeof(struct diradd), M_DIRADD, M_SOFTDEP_FLAGS|M_ZERO); dap->da_list.wk_type = D_DIRADD; dap->da_offset = offset; dap->da_newinum = newinum; dap->da_state = ATTACHED; if (newdirbp == NULL) { dap->da_state |= DEPCOMPLETE; ACQUIRE_LOCK(&lk); } else { dap->da_state |= MKDIR_BODY | MKDIR_PARENT; MALLOC(mkdir1, struct mkdir *, sizeof(struct mkdir), M_MKDIR, M_SOFTDEP_FLAGS); mkdir1->md_list.wk_type = D_MKDIR; mkdir1->md_state = MKDIR_BODY; mkdir1->md_diradd = dap; MALLOC(mkdir2, struct mkdir *, sizeof(struct mkdir), M_MKDIR, M_SOFTDEP_FLAGS); mkdir2->md_list.wk_type = D_MKDIR; mkdir2->md_state = MKDIR_PARENT; mkdir2->md_diradd = dap; /* * Dependency on "." and ".." being written to disk. */ mkdir1->md_buf = newdirbp; ACQUIRE_LOCK(&lk); LIST_INSERT_HEAD(&mkdirlisthd, mkdir1, md_mkdirs); WORKLIST_INSERT(&newdirbp->b_dep, &mkdir1->md_list); FREE_LOCK(&lk); bdwrite(newdirbp); /* * Dependency on link count increase for parent directory */ ACQUIRE_LOCK(&lk); if (inodedep_lookup(dp->i_fs, dp->i_number, 0, &inodedep) == 0 || (inodedep->id_state & ALLCOMPLETE) == ALLCOMPLETE) { dap->da_state &= ~MKDIR_PARENT; WORKITEM_FREE(mkdir2, D_MKDIR); } else { LIST_INSERT_HEAD(&mkdirlisthd, mkdir2, md_mkdirs); WORKLIST_INSERT(&inodedep->id_bufwait,&mkdir2->md_list); } } /* * Link into parent directory pagedep to await its being written. */ if (pagedep_lookup(dp, lbn, DEPALLOC, &pagedep) == 0) WORKLIST_INSERT(&bp->b_dep, &pagedep->pd_list); dap->da_pagedep = pagedep; LIST_INSERT_HEAD(&pagedep->pd_diraddhd[DIRADDHASH(offset)], dap, da_pdlist); /* * Link into its inodedep. Put it on the id_bufwait list if the inode * is not yet written. If it is written, do the post-inode write * processing to put it on the id_pendinghd list. */ (void) inodedep_lookup(fs, newinum, DEPALLOC, &inodedep); if ((inodedep->id_state & ALLCOMPLETE) == ALLCOMPLETE) diradd_inode_written(dap, inodedep); else WORKLIST_INSERT(&inodedep->id_bufwait, &dap->da_list); FREE_LOCK(&lk); } /* * This procedure is called to change the offset of a directory * entry when compacting a directory block which must be owned * exclusively by the caller. Note that the actual entry movement * must be done in this procedure to ensure that no I/O completions * occur while the move is in progress. */ void softdep_change_directoryentry_offset(dp, base, oldloc, newloc, entrysize) struct inode *dp; /* inode for directory */ caddr_t base; /* address of dp->i_offset */ caddr_t oldloc; /* address of old directory location */ caddr_t newloc; /* address of new directory location */ int entrysize; /* size of directory entry */ { int offset, oldoffset, newoffset; struct pagedep *pagedep; struct diradd *dap; ufs_lbn_t lbn; ACQUIRE_LOCK(&lk); lbn = lblkno(dp->i_fs, dp->i_offset); offset = blkoff(dp->i_fs, dp->i_offset); if (pagedep_lookup(dp, lbn, 0, &pagedep) == 0) goto done; oldoffset = offset + (oldloc - base); newoffset = offset + (newloc - base); for (dap = LIST_FIRST(&pagedep->pd_diraddhd[DIRADDHASH(oldoffset)]); dap; dap = LIST_NEXT(dap, da_pdlist)) { if (dap->da_offset != oldoffset) continue; dap->da_offset = newoffset; if (DIRADDHASH(newoffset) == DIRADDHASH(oldoffset)) break; LIST_REMOVE(dap, da_pdlist); LIST_INSERT_HEAD(&pagedep->pd_diraddhd[DIRADDHASH(newoffset)], dap, da_pdlist); break; } if (dap == NULL) { for (dap = LIST_FIRST(&pagedep->pd_pendinghd); dap; dap = LIST_NEXT(dap, da_pdlist)) { if (dap->da_offset == oldoffset) { dap->da_offset = newoffset; break; } } } done: bcopy(oldloc, newloc, entrysize); FREE_LOCK(&lk); } /* * Free a diradd dependency structure. This routine must be called * with splbio interrupts blocked. */ static void free_diradd(dap) struct diradd *dap; { struct dirrem *dirrem; struct pagedep *pagedep; struct inodedep *inodedep; struct mkdir *mkdir, *nextmd; #ifdef DEBUG if (lk.lkt_held == -1) panic("free_diradd: lock not held"); #endif WORKLIST_REMOVE(&dap->da_list); LIST_REMOVE(dap, da_pdlist); if ((dap->da_state & DIRCHG) == 0) { pagedep = dap->da_pagedep; } else { dirrem = dap->da_previous; pagedep = dirrem->dm_pagedep; dirrem->dm_dirinum = pagedep->pd_ino; add_to_worklist(&dirrem->dm_list); } if (inodedep_lookup(VFSTOUFS(pagedep->pd_mnt)->um_fs, dap->da_newinum, 0, &inodedep) != 0) (void) free_inodedep(inodedep); if ((dap->da_state & (MKDIR_PARENT | MKDIR_BODY)) != 0) { for (mkdir = LIST_FIRST(&mkdirlisthd); mkdir; mkdir = nextmd) { nextmd = LIST_NEXT(mkdir, md_mkdirs); if (mkdir->md_diradd != dap) continue; dap->da_state &= ~mkdir->md_state; WORKLIST_REMOVE(&mkdir->md_list); LIST_REMOVE(mkdir, md_mkdirs); WORKITEM_FREE(mkdir, D_MKDIR); } if ((dap->da_state & (MKDIR_PARENT | MKDIR_BODY)) != 0) panic("free_diradd: unfound ref"); } WORKITEM_FREE(dap, D_DIRADD); } /* * Directory entry removal dependencies. * * When removing a directory entry, the entry's inode pointer must be * zero'ed on disk before the corresponding inode's link count is decremented * (possibly freeing the inode for re-use). This dependency is handled by * updating the directory entry but delaying the inode count reduction until * after the directory block has been written to disk. After this point, the * inode count can be decremented whenever it is convenient. */ /* * This routine should be called immediately after removing * a directory entry. The inode's link count should not be * decremented by the calling procedure -- the soft updates * code will do this task when it is safe. */ void softdep_setup_remove(bp, dp, ip, isrmdir) struct buf *bp; /* buffer containing directory block */ struct inode *dp; /* inode for the directory being modified */ struct inode *ip; /* inode for directory entry being removed */ int isrmdir; /* indicates if doing RMDIR */ { struct dirrem *dirrem, *prevdirrem; /* * Allocate a new dirrem if appropriate and ACQUIRE_LOCK. */ dirrem = newdirrem(bp, dp, ip, isrmdir, &prevdirrem); /* * If the COMPLETE flag is clear, then there were no active * entries and we want to roll back to a zeroed entry until * the new inode is committed to disk. If the COMPLETE flag is * set then we have deleted an entry that never made it to * disk. If the entry we deleted resulted from a name change, * then the old name still resides on disk. We cannot delete * its inode (returned to us in prevdirrem) until the zeroed * directory entry gets to disk. The new inode has never been * referenced on the disk, so can be deleted immediately. */ if ((dirrem->dm_state & COMPLETE) == 0) { LIST_INSERT_HEAD(&dirrem->dm_pagedep->pd_dirremhd, dirrem, dm_next); FREE_LOCK(&lk); } else { if (prevdirrem != NULL) LIST_INSERT_HEAD(&dirrem->dm_pagedep->pd_dirremhd, prevdirrem, dm_next); dirrem->dm_dirinum = dirrem->dm_pagedep->pd_ino; FREE_LOCK(&lk); handle_workitem_remove(dirrem); } } /* * Allocate a new dirrem if appropriate and return it along with * its associated pagedep. Called without a lock, returns with lock. */ static long num_dirrem; /* number of dirrem allocated */ static struct dirrem * newdirrem(bp, dp, ip, isrmdir, prevdirremp) struct buf *bp; /* buffer containing directory block */ struct inode *dp; /* inode for the directory being modified */ struct inode *ip; /* inode for directory entry being removed */ int isrmdir; /* indicates if doing RMDIR */ struct dirrem **prevdirremp; /* previously referenced inode, if any */ { int offset; ufs_lbn_t lbn; struct diradd *dap; struct dirrem *dirrem; struct pagedep *pagedep; /* * Whiteouts have no deletion dependencies. */ if (ip == NULL) panic("newdirrem: whiteout"); /* * If we are over our limit, try to improve the situation. * Limiting the number of dirrem structures will also limit * the number of freefile and freeblks structures. */ if (num_dirrem > max_softdeps / 2) (void) request_cleanup(FLUSH_REMOVE, 0); num_dirrem += 1; MALLOC(dirrem, struct dirrem *, sizeof(struct dirrem), M_DIRREM, M_SOFTDEP_FLAGS|M_ZERO); dirrem->dm_list.wk_type = D_DIRREM; dirrem->dm_state = isrmdir ? RMDIR : 0; dirrem->dm_mnt = ITOV(ip)->v_mount; dirrem->dm_oldinum = ip->i_number; *prevdirremp = NULL; ACQUIRE_LOCK(&lk); lbn = lblkno(dp->i_fs, dp->i_offset); offset = blkoff(dp->i_fs, dp->i_offset); if (pagedep_lookup(dp, lbn, DEPALLOC, &pagedep) == 0) WORKLIST_INSERT(&bp->b_dep, &pagedep->pd_list); dirrem->dm_pagedep = pagedep; /* * Check for a diradd dependency for the same directory entry. * If present, then both dependencies become obsolete and can * be de-allocated. Check for an entry on both the pd_dirraddhd * list and the pd_pendinghd list. */ for (dap = LIST_FIRST(&pagedep->pd_diraddhd[DIRADDHASH(offset)]); dap; dap = LIST_NEXT(dap, da_pdlist)) if (dap->da_offset == offset) break; if (dap == NULL) { for (dap = LIST_FIRST(&pagedep->pd_pendinghd); dap; dap = LIST_NEXT(dap, da_pdlist)) if (dap->da_offset == offset) break; if (dap == NULL) return (dirrem); } /* * Must be ATTACHED at this point. */ if ((dap->da_state & ATTACHED) == 0) panic("newdirrem: not ATTACHED"); if (dap->da_newinum != ip->i_number) panic("newdirrem: inum %d should be %d", ip->i_number, dap->da_newinum); /* * If we are deleting a changed name that never made it to disk, * then return the dirrem describing the previous inode (which * represents the inode currently referenced from this entry on disk). */ if ((dap->da_state & DIRCHG) != 0) { *prevdirremp = dap->da_previous; dap->da_state &= ~DIRCHG; dap->da_pagedep = pagedep; } /* * We are deleting an entry that never made it to disk. * Mark it COMPLETE so we can delete its inode immediately. */ dirrem->dm_state |= COMPLETE; free_diradd(dap); return (dirrem); } /* * Directory entry change dependencies. * * Changing an existing directory entry requires that an add operation * be completed first followed by a deletion. The semantics for the addition * are identical to the description of adding a new entry above except * that the rollback is to the old inode number rather than zero. Once * the addition dependency is completed, the removal is done as described * in the removal routine above. */ /* * This routine should be called immediately after changing * a directory entry. The inode's link count should not be * decremented by the calling procedure -- the soft updates * code will perform this task when it is safe. */ void softdep_setup_directory_change(bp, dp, ip, newinum, isrmdir) struct buf *bp; /* buffer containing directory block */ struct inode *dp; /* inode for the directory being modified */ struct inode *ip; /* inode for directory entry being removed */ long newinum; /* new inode number for changed entry */ int isrmdir; /* indicates if doing RMDIR */ { int offset; struct diradd *dap = NULL; struct dirrem *dirrem, *prevdirrem; struct pagedep *pagedep; struct inodedep *inodedep; offset = blkoff(dp->i_fs, dp->i_offset); /* * Whiteouts do not need diradd dependencies. */ if (newinum != WINO) { MALLOC(dap, struct diradd *, sizeof(struct diradd), M_DIRADD, M_SOFTDEP_FLAGS|M_ZERO); dap->da_list.wk_type = D_DIRADD; dap->da_state = DIRCHG | ATTACHED | DEPCOMPLETE; dap->da_offset = offset; dap->da_newinum = newinum; } /* * Allocate a new dirrem and ACQUIRE_LOCK. */ dirrem = newdirrem(bp, dp, ip, isrmdir, &prevdirrem); pagedep = dirrem->dm_pagedep; /* * The possible values for isrmdir: * 0 - non-directory file rename * 1 - directory rename within same directory * inum - directory rename to new directory of given inode number * When renaming to a new directory, we are both deleting and * creating a new directory entry, so the link count on the new * directory should not change. Thus we do not need the followup * dirrem which is usually done in handle_workitem_remove. We set * the DIRCHG flag to tell handle_workitem_remove to skip the * followup dirrem. */ if (isrmdir > 1) dirrem->dm_state |= DIRCHG; /* * Whiteouts have no additional dependencies, * so just put the dirrem on the correct list. */ if (newinum == WINO) { if ((dirrem->dm_state & COMPLETE) == 0) { LIST_INSERT_HEAD(&pagedep->pd_dirremhd, dirrem, dm_next); } else { dirrem->dm_dirinum = pagedep->pd_ino; add_to_worklist(&dirrem->dm_list); } FREE_LOCK(&lk); return; } /* * If the COMPLETE flag is clear, then there were no active * entries and we want to roll back to the previous inode until * the new inode is committed to disk. If the COMPLETE flag is * set, then we have deleted an entry that never made it to disk. * If the entry we deleted resulted from a name change, then the old * inode reference still resides on disk. Any rollback that we do * needs to be to that old inode (returned to us in prevdirrem). If * the entry we deleted resulted from a create, then there is * no entry on the disk, so we want to roll back to zero rather * than the uncommitted inode. In either of the COMPLETE cases we * want to immediately free the unwritten and unreferenced inode. */ if ((dirrem->dm_state & COMPLETE) == 0) { dap->da_previous = dirrem; } else { if (prevdirrem != NULL) { dap->da_previous = prevdirrem; } else { dap->da_state &= ~DIRCHG; dap->da_pagedep = pagedep; } dirrem->dm_dirinum = pagedep->pd_ino; add_to_worklist(&dirrem->dm_list); } /* * Link into its inodedep. Put it on the id_bufwait list if the inode * is not yet written. If it is written, do the post-inode write * processing to put it on the id_pendinghd list. */ if (inodedep_lookup(dp->i_fs, newinum, DEPALLOC, &inodedep) == 0 || (inodedep->id_state & ALLCOMPLETE) == ALLCOMPLETE) { dap->da_state |= COMPLETE; LIST_INSERT_HEAD(&pagedep->pd_pendinghd, dap, da_pdlist); WORKLIST_INSERT(&inodedep->id_pendinghd, &dap->da_list); } else { LIST_INSERT_HEAD(&pagedep->pd_diraddhd[DIRADDHASH(offset)], dap, da_pdlist); WORKLIST_INSERT(&inodedep->id_bufwait, &dap->da_list); } FREE_LOCK(&lk); } /* * Called whenever the link count on an inode is changed. * It creates an inode dependency so that the new reference(s) * to the inode cannot be committed to disk until the updated * inode has been written. */ void softdep_change_linkcnt(ip) struct inode *ip; /* the inode with the increased link count */ { struct inodedep *inodedep; ACQUIRE_LOCK(&lk); (void) inodedep_lookup(ip->i_fs, ip->i_number, DEPALLOC, &inodedep); if (ip->i_nlink < ip->i_effnlink) panic("softdep_change_linkcnt: bad delta"); inodedep->id_nlinkdelta = ip->i_nlink - ip->i_effnlink; FREE_LOCK(&lk); } /* * This workitem decrements the inode's link count. * If the link count reaches zero, the file is removed. */ static void handle_workitem_remove(dirrem) struct dirrem *dirrem; { struct proc *p = CURPROC; /* XXX */ struct inodedep *inodedep; struct vnode *vp; struct inode *ip; ino_t oldinum; int error; if ((error = VFS_VGET(dirrem->dm_mnt, dirrem->dm_oldinum, &vp)) != 0) { softdep_error("handle_workitem_remove: vget", error); return; } ip = VTOI(vp); ACQUIRE_LOCK(&lk); if ((inodedep_lookup(ip->i_fs, dirrem->dm_oldinum, 0, &inodedep)) == 0) panic("handle_workitem_remove: lost inodedep"); /* * Normal file deletion. */ if ((dirrem->dm_state & RMDIR) == 0) { ip->i_nlink--; ip->i_flag |= IN_CHANGE; if (ip->i_nlink < ip->i_effnlink) panic("handle_workitem_remove: bad file delta"); inodedep->id_nlinkdelta = ip->i_nlink - ip->i_effnlink; FREE_LOCK(&lk); vput(vp); num_dirrem -= 1; WORKITEM_FREE(dirrem, D_DIRREM); return; } /* * Directory deletion. Decrement reference count for both the * just deleted parent directory entry and the reference for ".". * Next truncate the directory to length zero. When the * truncation completes, arrange to have the reference count on * the parent decremented to account for the loss of "..". */ ip->i_nlink -= 2; ip->i_flag |= IN_CHANGE; if (ip->i_nlink < ip->i_effnlink) panic("handle_workitem_remove: bad dir delta"); inodedep->id_nlinkdelta = ip->i_nlink - ip->i_effnlink; FREE_LOCK(&lk); if ((error = UFS_TRUNCATE(vp, (off_t)0, 0, p->p_ucred, p)) != 0) softdep_error("handle_workitem_remove: truncate", error); /* * Rename a directory to a new parent. Since, we are both deleting * and creating a new directory entry, the link count on the new * directory should not change. Thus we skip the followup dirrem. */ if (dirrem->dm_state & DIRCHG) { vput(vp); num_dirrem -= 1; WORKITEM_FREE(dirrem, D_DIRREM); return; } /* * If the inodedep does not exist, then the zero'ed inode has * been written to disk. If the allocated inode has never been * written to disk, then the on-disk inode is zero'ed. In either * case we can remove the file immediately. */ ACQUIRE_LOCK(&lk); dirrem->dm_state = 0; oldinum = dirrem->dm_oldinum; dirrem->dm_oldinum = dirrem->dm_dirinum; if (inodedep_lookup(ip->i_fs, oldinum, 0, &inodedep) == 0 || check_inode_unwritten(inodedep)) { FREE_LOCK(&lk); vput(vp); handle_workitem_remove(dirrem); return; } WORKLIST_INSERT(&inodedep->id_inowait, &dirrem->dm_list); FREE_LOCK(&lk); vput(vp); } /* * Inode de-allocation dependencies. * * When an inode's link count is reduced to zero, it can be de-allocated. We * found it convenient to postpone de-allocation until after the inode is * written to disk with its new link count (zero). At this point, all of the * on-disk inode's block pointers are nullified and, with careful dependency * list ordering, all dependencies related to the inode will be satisfied and * the corresponding dependency structures de-allocated. So, if/when the * inode is reused, there will be no mixing of old dependencies with new * ones. This artificial dependency is set up by the block de-allocation * procedure above (softdep_setup_freeblocks) and completed by the * following procedure. */ static void handle_workitem_freefile(freefile) struct freefile *freefile; { struct fs *fs; struct vnode vp; struct inode tip; struct inodedep *idp; int error; fs = VFSTOUFS(freefile->fx_mnt)->um_fs; #ifdef DEBUG ACQUIRE_LOCK(&lk); if (inodedep_lookup(fs, freefile->fx_oldinum, 0, &idp)) panic("handle_workitem_freefile: inodedep survived"); FREE_LOCK(&lk); #endif tip.i_devvp = freefile->fx_devvp; tip.i_dev = freefile->fx_devvp->v_rdev; tip.i_fs = fs; tip.i_vnode = &vp; vp.v_data = &tip; if ((error = ffs_freefile(&vp, freefile->fx_oldinum, freefile->fx_mode)) != 0) softdep_error("handle_workitem_freefile", error); WORKITEM_FREE(freefile, D_FREEFILE); } /* * Disk writes. * * The dependency structures constructed above are most actively used when file * system blocks are written to disk. No constraints are placed on when a * block can be written, but unsatisfied update dependencies are made safe by * modifying (or replacing) the source memory for the duration of the disk * write. When the disk write completes, the memory block is again brought * up-to-date. * * In-core inode structure reclamation. * * Because there are a finite number of "in-core" inode structures, they are * reused regularly. By transferring all inode-related dependencies to the * in-memory inode block and indexing them separately (via "inodedep"s), we * can allow "in-core" inode structures to be reused at any time and avoid * any increase in contention. * * Called just before entering the device driver to initiate a new disk I/O. * The buffer must be locked, thus, no I/O completion operations can occur * while we are manipulating its associated dependencies. */ static void softdep_disk_io_initiation(bp) struct buf *bp; /* structure describing disk write to occur */ { struct worklist *wk, *nextwk; struct indirdep *indirdep; /* * We only care about write operations. There should never * be dependencies for reads. */ if (bp->b_iocmd == BIO_READ) panic("softdep_disk_io_initiation: read"); /* * Do any necessary pre-I/O processing. */ for (wk = LIST_FIRST(&bp->b_dep); wk; wk = nextwk) { nextwk = LIST_NEXT(wk, wk_list); switch (wk->wk_type) { case D_PAGEDEP: initiate_write_filepage(WK_PAGEDEP(wk), bp); continue; case D_INODEDEP: initiate_write_inodeblock(WK_INODEDEP(wk), bp); continue; case D_INDIRDEP: indirdep = WK_INDIRDEP(wk); if (indirdep->ir_state & GOINGAWAY) panic("disk_io_initiation: indirdep gone"); /* * If there are no remaining dependencies, this * will be writing the real pointers, so the * dependency can be freed. */ if (LIST_FIRST(&indirdep->ir_deplisthd) == NULL) { indirdep->ir_savebp->b_flags |= B_INVAL | B_NOCACHE; brelse(indirdep->ir_savebp); /* inline expand WORKLIST_REMOVE(wk); */ wk->wk_state &= ~ONWORKLIST; LIST_REMOVE(wk, wk_list); WORKITEM_FREE(indirdep, D_INDIRDEP); continue; } /* * Replace up-to-date version with safe version. */ MALLOC(indirdep->ir_saveddata, caddr_t, bp->b_bcount, M_INDIRDEP, M_SOFTDEP_FLAGS); ACQUIRE_LOCK(&lk); indirdep->ir_state &= ~ATTACHED; indirdep->ir_state |= UNDONE; bcopy(bp->b_data, indirdep->ir_saveddata, bp->b_bcount); bcopy(indirdep->ir_savebp->b_data, bp->b_data, bp->b_bcount); FREE_LOCK(&lk); continue; case D_MKDIR: case D_BMSAFEMAP: case D_ALLOCDIRECT: case D_ALLOCINDIR: continue; default: panic("handle_disk_io_initiation: Unexpected type %s", TYPENAME(wk->wk_type)); /* NOTREACHED */ } } } /* * Called from within the procedure above to deal with unsatisfied * allocation dependencies in a directory. The buffer must be locked, * thus, no I/O completion operations can occur while we are * manipulating its associated dependencies. */ static void initiate_write_filepage(pagedep, bp) struct pagedep *pagedep; struct buf *bp; { struct diradd *dap; struct direct *ep; int i; if (pagedep->pd_state & IOSTARTED) { /* * This can only happen if there is a driver that does not * understand chaining. Here biodone will reissue the call * to strategy for the incomplete buffers. */ printf("initiate_write_filepage: already started\n"); return; } pagedep->pd_state |= IOSTARTED; ACQUIRE_LOCK(&lk); for (i = 0; i < DAHASHSZ; i++) { for (dap = LIST_FIRST(&pagedep->pd_diraddhd[i]); dap; dap = LIST_NEXT(dap, da_pdlist)) { ep = (struct direct *) ((char *)bp->b_data + dap->da_offset); if (ep->d_ino != dap->da_newinum) panic("%s: dir inum %d != new %d", "initiate_write_filepage", ep->d_ino, dap->da_newinum); if (dap->da_state & DIRCHG) ep->d_ino = dap->da_previous->dm_oldinum; else ep->d_ino = 0; dap->da_state &= ~ATTACHED; dap->da_state |= UNDONE; } } FREE_LOCK(&lk); } /* * Called from within the procedure above to deal with unsatisfied * allocation dependencies in an inodeblock. The buffer must be * locked, thus, no I/O completion operations can occur while we * are manipulating its associated dependencies. */ static void initiate_write_inodeblock(inodedep, bp) struct inodedep *inodedep; struct buf *bp; /* The inode block */ { struct allocdirect *adp, *lastadp; struct dinode *dp; struct fs *fs; ufs_lbn_t prevlbn = 0; int i, deplist; if (inodedep->id_state & IOSTARTED) panic("initiate_write_inodeblock: already started"); inodedep->id_state |= IOSTARTED; fs = inodedep->id_fs; dp = (struct dinode *)bp->b_data + ino_to_fsbo(fs, inodedep->id_ino); /* * If the bitmap is not yet written, then the allocated * inode cannot be written to disk. */ if ((inodedep->id_state & DEPCOMPLETE) == 0) { if (inodedep->id_savedino != NULL) panic("initiate_write_inodeblock: already doing I/O"); MALLOC(inodedep->id_savedino, struct dinode *, sizeof(struct dinode), M_INODEDEP, M_SOFTDEP_FLAGS); *inodedep->id_savedino = *dp; bzero((caddr_t)dp, sizeof(struct dinode)); return; } /* * If no dependencies, then there is nothing to roll back. */ inodedep->id_savedsize = dp->di_size; if (TAILQ_FIRST(&inodedep->id_inoupdt) == NULL) return; /* * Set the dependencies to busy. */ ACQUIRE_LOCK(&lk); for (deplist = 0, adp = TAILQ_FIRST(&inodedep->id_inoupdt); adp; adp = TAILQ_NEXT(adp, ad_next)) { #ifdef DIAGNOSTIC if (deplist != 0 && prevlbn >= adp->ad_lbn) panic("softdep_write_inodeblock: lbn order"); prevlbn = adp->ad_lbn; if (adp->ad_lbn < NDADDR && dp->di_db[adp->ad_lbn] != adp->ad_newblkno) panic("%s: direct pointer #%ld mismatch %d != %d", "softdep_write_inodeblock", adp->ad_lbn, dp->di_db[adp->ad_lbn], adp->ad_newblkno); if (adp->ad_lbn >= NDADDR && dp->di_ib[adp->ad_lbn - NDADDR] != adp->ad_newblkno) panic("%s: indirect pointer #%ld mismatch %d != %d", "softdep_write_inodeblock", adp->ad_lbn - NDADDR, dp->di_ib[adp->ad_lbn - NDADDR], adp->ad_newblkno); deplist |= 1 << adp->ad_lbn; if ((adp->ad_state & ATTACHED) == 0) panic("softdep_write_inodeblock: Unknown state 0x%x", adp->ad_state); #endif /* DIAGNOSTIC */ adp->ad_state &= ~ATTACHED; adp->ad_state |= UNDONE; } /* * The on-disk inode cannot claim to be any larger than the last * fragment that has been written. Otherwise, the on-disk inode * might have fragments that were not the last block in the file * which would corrupt the filesystem. */ for (lastadp = NULL, adp = TAILQ_FIRST(&inodedep->id_inoupdt); adp; lastadp = adp, adp = TAILQ_NEXT(adp, ad_next)) { if (adp->ad_lbn >= NDADDR) break; dp->di_db[adp->ad_lbn] = adp->ad_oldblkno; /* keep going until hitting a rollback to a frag */ if (adp->ad_oldsize == 0 || adp->ad_oldsize == fs->fs_bsize) continue; dp->di_size = fs->fs_bsize * adp->ad_lbn + adp->ad_oldsize; for (i = adp->ad_lbn + 1; i < NDADDR; i++) { #ifdef DIAGNOSTIC if (dp->di_db[i] != 0 && (deplist & (1 << i)) == 0) panic("softdep_write_inodeblock: lost dep1"); #endif /* DIAGNOSTIC */ dp->di_db[i] = 0; } for (i = 0; i < NIADDR; i++) { #ifdef DIAGNOSTIC if (dp->di_ib[i] != 0 && (deplist & ((1 << NDADDR) << i)) == 0) panic("softdep_write_inodeblock: lost dep2"); #endif /* DIAGNOSTIC */ dp->di_ib[i] = 0; } FREE_LOCK(&lk); return; } /* * If we have zero'ed out the last allocated block of the file, * roll back the size to the last currently allocated block. * We know that this last allocated block is a full-sized as * we already checked for fragments in the loop above. */ if (lastadp != NULL && dp->di_size <= (lastadp->ad_lbn + 1) * fs->fs_bsize) { for (i = lastadp->ad_lbn; i >= 0; i--) if (dp->di_db[i] != 0) break; dp->di_size = (i + 1) * fs->fs_bsize; } /* * The only dependencies are for indirect blocks. * * The file size for indirect block additions is not guaranteed. * Such a guarantee would be non-trivial to achieve. The conventional * synchronous write implementation also does not make this guarantee. * Fsck should catch and fix discrepancies. Arguably, the file size * can be over-estimated without destroying integrity when the file * moves into the indirect blocks (i.e., is large). If we want to * postpone fsck, we are stuck with this argument. */ for (; adp; adp = TAILQ_NEXT(adp, ad_next)) dp->di_ib[adp->ad_lbn - NDADDR] = 0; FREE_LOCK(&lk); } /* * This routine is called during the completion interrupt * service routine for a disk write (from the procedure called * by the device driver to inform the file system caches of * a request completion). It should be called early in this * procedure, before the block is made available to other * processes or other routines are called. */ static void softdep_disk_write_complete(bp) struct buf *bp; /* describes the completed disk write */ { struct worklist *wk; struct workhead reattach; struct newblk *newblk; struct allocindir *aip; struct allocdirect *adp; struct indirdep *indirdep; struct inodedep *inodedep; struct bmsafemap *bmsafemap; #ifdef DEBUG if (lk.lkt_held != -1) panic("softdep_disk_write_complete: lock is held"); lk.lkt_held = -2; #endif LIST_INIT(&reattach); while ((wk = LIST_FIRST(&bp->b_dep)) != NULL) { WORKLIST_REMOVE(wk); switch (wk->wk_type) { case D_PAGEDEP: if (handle_written_filepage(WK_PAGEDEP(wk), bp)) WORKLIST_INSERT(&reattach, wk); continue; case D_INODEDEP: if (handle_written_inodeblock(WK_INODEDEP(wk), bp)) WORKLIST_INSERT(&reattach, wk); continue; case D_BMSAFEMAP: bmsafemap = WK_BMSAFEMAP(wk); while ((newblk = LIST_FIRST(&bmsafemap->sm_newblkhd))) { newblk->nb_state |= DEPCOMPLETE; newblk->nb_bmsafemap = NULL; LIST_REMOVE(newblk, nb_deps); } while ((adp = LIST_FIRST(&bmsafemap->sm_allocdirecthd))) { adp->ad_state |= DEPCOMPLETE; adp->ad_buf = NULL; LIST_REMOVE(adp, ad_deps); handle_allocdirect_partdone(adp); } while ((aip = LIST_FIRST(&bmsafemap->sm_allocindirhd))) { aip->ai_state |= DEPCOMPLETE; aip->ai_buf = NULL; LIST_REMOVE(aip, ai_deps); handle_allocindir_partdone(aip); } while ((inodedep = LIST_FIRST(&bmsafemap->sm_inodedephd)) != NULL) { inodedep->id_state |= DEPCOMPLETE; LIST_REMOVE(inodedep, id_deps); inodedep->id_buf = NULL; } WORKITEM_FREE(bmsafemap, D_BMSAFEMAP); continue; case D_MKDIR: handle_written_mkdir(WK_MKDIR(wk), MKDIR_BODY); continue; case D_ALLOCDIRECT: adp = WK_ALLOCDIRECT(wk); adp->ad_state |= COMPLETE; handle_allocdirect_partdone(adp); continue; case D_ALLOCINDIR: aip = WK_ALLOCINDIR(wk); aip->ai_state |= COMPLETE; handle_allocindir_partdone(aip); continue; case D_INDIRDEP: indirdep = WK_INDIRDEP(wk); if (indirdep->ir_state & GOINGAWAY) panic("disk_write_complete: indirdep gone"); bcopy(indirdep->ir_saveddata, bp->b_data, bp->b_bcount); FREE(indirdep->ir_saveddata, M_INDIRDEP); indirdep->ir_saveddata = 0; indirdep->ir_state &= ~UNDONE; indirdep->ir_state |= ATTACHED; while ((aip = LIST_FIRST(&indirdep->ir_donehd)) != 0) { handle_allocindir_partdone(aip); if (aip == LIST_FIRST(&indirdep->ir_donehd)) panic("disk_write_complete: not gone"); } WORKLIST_INSERT(&reattach, wk); if ((bp->b_flags & B_DELWRI) == 0) stat_indir_blk_ptrs++; bdirty(bp); continue; default: panic("handle_disk_write_complete: Unknown type %s", TYPENAME(wk->wk_type)); /* NOTREACHED */ } } /* * Reattach any requests that must be redone. */ while ((wk = LIST_FIRST(&reattach)) != NULL) { WORKLIST_REMOVE(wk); WORKLIST_INSERT(&bp->b_dep, wk); } #ifdef DEBUG if (lk.lkt_held != -2) panic("softdep_disk_write_complete: lock lost"); lk.lkt_held = -1; #endif } /* * Called from within softdep_disk_write_complete above. Note that * this routine is always called from interrupt level with further * splbio interrupts blocked. */ static void handle_allocdirect_partdone(adp) struct allocdirect *adp; /* the completed allocdirect */ { struct allocdirect *listadp; struct inodedep *inodedep; long bsize, delay; if ((adp->ad_state & ALLCOMPLETE) != ALLCOMPLETE) return; if (adp->ad_buf != NULL) panic("handle_allocdirect_partdone: dangling dep"); /* * The on-disk inode cannot claim to be any larger than the last * fragment that has been written. Otherwise, the on-disk inode * might have fragments that were not the last block in the file * which would corrupt the filesystem. Thus, we cannot free any * allocdirects after one whose ad_oldblkno claims a fragment as * these blocks must be rolled back to zero before writing the inode. * We check the currently active set of allocdirects in id_inoupdt. */ inodedep = adp->ad_inodedep; bsize = inodedep->id_fs->fs_bsize; for (listadp = TAILQ_FIRST(&inodedep->id_inoupdt); listadp; listadp = TAILQ_NEXT(listadp, ad_next)) { /* found our block */ if (listadp == adp) break; /* continue if ad_oldlbn is not a fragment */ if (listadp->ad_oldsize == 0 || listadp->ad_oldsize == bsize) continue; /* hit a fragment */ return; } /* * If we have reached the end of the current list without * finding the just finished dependency, then it must be * on the future dependency list. Future dependencies cannot * be freed until they are moved to the current list. */ if (listadp == NULL) { #ifdef DEBUG for (listadp = TAILQ_FIRST(&inodedep->id_newinoupdt); listadp; listadp = TAILQ_NEXT(listadp, ad_next)) /* found our block */ if (listadp == adp) break; if (listadp == NULL) panic("handle_allocdirect_partdone: lost dep"); #endif /* DEBUG */ return; } /* * If we have found the just finished dependency, then free * it along with anything that follows it that is complete. * If the inode still has a bitmap dependency, then it has * never been written to disk, hence the on-disk inode cannot * reference the old fragment so we can free it without delay. */ delay = (inodedep->id_state & DEPCOMPLETE); for (; adp; adp = listadp) { listadp = TAILQ_NEXT(adp, ad_next); if ((adp->ad_state & ALLCOMPLETE) != ALLCOMPLETE) return; free_allocdirect(&inodedep->id_inoupdt, adp, delay); } } /* * Called from within softdep_disk_write_complete above. Note that * this routine is always called from interrupt level with further * splbio interrupts blocked. */ static void handle_allocindir_partdone(aip) struct allocindir *aip; /* the completed allocindir */ { struct indirdep *indirdep; if ((aip->ai_state & ALLCOMPLETE) != ALLCOMPLETE) return; if (aip->ai_buf != NULL) panic("handle_allocindir_partdone: dangling dependency"); indirdep = aip->ai_indirdep; if (indirdep->ir_state & UNDONE) { LIST_REMOVE(aip, ai_next); LIST_INSERT_HEAD(&indirdep->ir_donehd, aip, ai_next); return; } ((ufs_daddr_t *)indirdep->ir_savebp->b_data)[aip->ai_offset] = aip->ai_newblkno; LIST_REMOVE(aip, ai_next); if (aip->ai_freefrag != NULL) add_to_worklist(&aip->ai_freefrag->ff_list); WORKITEM_FREE(aip, D_ALLOCINDIR); } /* * Called from within softdep_disk_write_complete above to restore * in-memory inode block contents to their most up-to-date state. Note * that this routine is always called from interrupt level with further * splbio interrupts blocked. */ static int handle_written_inodeblock(inodedep, bp) struct inodedep *inodedep; struct buf *bp; /* buffer containing the inode block */ { struct worklist *wk, *filefree; struct allocdirect *adp, *nextadp; struct dinode *dp; int hadchanges; if ((inodedep->id_state & IOSTARTED) == 0) panic("handle_written_inodeblock: not started"); inodedep->id_state &= ~IOSTARTED; inodedep->id_state |= COMPLETE; dp = (struct dinode *)bp->b_data + ino_to_fsbo(inodedep->id_fs, inodedep->id_ino); /* * If we had to rollback the inode allocation because of * bitmaps being incomplete, then simply restore it. * Keep the block dirty so that it will not be reclaimed until * all associated dependencies have been cleared and the * corresponding updates written to disk. */ if (inodedep->id_savedino != NULL) { *dp = *inodedep->id_savedino; FREE(inodedep->id_savedino, M_INODEDEP); inodedep->id_savedino = NULL; if ((bp->b_flags & B_DELWRI) == 0) stat_inode_bitmap++; bdirty(bp); return (1); } /* * Roll forward anything that had to be rolled back before * the inode could be updated. */ hadchanges = 0; for (adp = TAILQ_FIRST(&inodedep->id_inoupdt); adp; adp = nextadp) { nextadp = TAILQ_NEXT(adp, ad_next); if (adp->ad_state & ATTACHED) panic("handle_written_inodeblock: new entry"); if (adp->ad_lbn < NDADDR) { if (dp->di_db[adp->ad_lbn] != adp->ad_oldblkno) panic("%s: %s #%ld mismatch %d != %d", "handle_written_inodeblock", "direct pointer", adp->ad_lbn, dp->di_db[adp->ad_lbn], adp->ad_oldblkno); dp->di_db[adp->ad_lbn] = adp->ad_newblkno; } else { if (dp->di_ib[adp->ad_lbn - NDADDR] != 0) panic("%s: %s #%ld allocated as %d", "handle_written_inodeblock", "indirect pointer", adp->ad_lbn - NDADDR, dp->di_ib[adp->ad_lbn - NDADDR]); dp->di_ib[adp->ad_lbn - NDADDR] = adp->ad_newblkno; } adp->ad_state &= ~UNDONE; adp->ad_state |= ATTACHED; hadchanges = 1; } if (hadchanges && (bp->b_flags & B_DELWRI) == 0) stat_direct_blk_ptrs++; /* * Reset the file size to its most up-to-date value. */ if (inodedep->id_savedsize == -1) panic("handle_written_inodeblock: bad size"); if (dp->di_size != inodedep->id_savedsize) { dp->di_size = inodedep->id_savedsize; hadchanges = 1; } inodedep->id_savedsize = -1; /* * If there were any rollbacks in the inode block, then it must be * marked dirty so that its will eventually get written back in * its correct form. */ if (hadchanges) bdirty(bp); /* * Process any allocdirects that completed during the update. */ if ((adp = TAILQ_FIRST(&inodedep->id_inoupdt)) != NULL) handle_allocdirect_partdone(adp); /* * Process deallocations that were held pending until the * inode had been written to disk. Freeing of the inode * is delayed until after all blocks have been freed to * avoid creation of new triples * before the old ones have been deleted. */ filefree = NULL; while ((wk = LIST_FIRST(&inodedep->id_bufwait)) != NULL) { WORKLIST_REMOVE(wk); switch (wk->wk_type) { case D_FREEFILE: /* * We defer adding filefree to the worklist until * all other additions have been made to ensure * that it will be done after all the old blocks * have been freed. */ if (filefree != NULL) panic("handle_written_inodeblock: filefree"); filefree = wk; continue; case D_MKDIR: handle_written_mkdir(WK_MKDIR(wk), MKDIR_PARENT); continue; case D_DIRADD: diradd_inode_written(WK_DIRADD(wk), inodedep); continue; case D_FREEBLKS: case D_FREEFRAG: case D_DIRREM: add_to_worklist(wk); continue; default: panic("handle_written_inodeblock: Unknown type %s", TYPENAME(wk->wk_type)); /* NOTREACHED */ } } if (filefree != NULL) { if (free_inodedep(inodedep) == 0) panic("handle_written_inodeblock: live inodedep"); add_to_worklist(filefree); return (0); } /* * If no outstanding dependencies, free it. */ if (free_inodedep(inodedep) || TAILQ_FIRST(&inodedep->id_inoupdt) == 0) return (0); return (hadchanges); } /* * Process a diradd entry after its dependent inode has been written. * This routine must be called with splbio interrupts blocked. */ static void diradd_inode_written(dap, inodedep) struct diradd *dap; struct inodedep *inodedep; { struct pagedep *pagedep; dap->da_state |= COMPLETE; if ((dap->da_state & ALLCOMPLETE) == ALLCOMPLETE) { if (dap->da_state & DIRCHG) pagedep = dap->da_previous->dm_pagedep; else pagedep = dap->da_pagedep; LIST_REMOVE(dap, da_pdlist); LIST_INSERT_HEAD(&pagedep->pd_pendinghd, dap, da_pdlist); } WORKLIST_INSERT(&inodedep->id_pendinghd, &dap->da_list); } /* * Handle the completion of a mkdir dependency. */ static void handle_written_mkdir(mkdir, type) struct mkdir *mkdir; int type; { struct diradd *dap; struct pagedep *pagedep; if (mkdir->md_state != type) panic("handle_written_mkdir: bad type"); dap = mkdir->md_diradd; dap->da_state &= ~type; if ((dap->da_state & (MKDIR_PARENT | MKDIR_BODY)) == 0) dap->da_state |= DEPCOMPLETE; if ((dap->da_state & ALLCOMPLETE) == ALLCOMPLETE) { if (dap->da_state & DIRCHG) pagedep = dap->da_previous->dm_pagedep; else pagedep = dap->da_pagedep; LIST_REMOVE(dap, da_pdlist); LIST_INSERT_HEAD(&pagedep->pd_pendinghd, dap, da_pdlist); } LIST_REMOVE(mkdir, md_mkdirs); WORKITEM_FREE(mkdir, D_MKDIR); } /* * Called from within softdep_disk_write_complete above. * A write operation was just completed. Removed inodes can * now be freed and associated block pointers may be committed. * Note that this routine is always called from interrupt level * with further splbio interrupts blocked. */ static int handle_written_filepage(pagedep, bp) struct pagedep *pagedep; struct buf *bp; /* buffer containing the written page */ { struct dirrem *dirrem; struct diradd *dap, *nextdap; struct direct *ep; int i, chgs; if ((pagedep->pd_state & IOSTARTED) == 0) panic("handle_written_filepage: not started"); pagedep->pd_state &= ~IOSTARTED; /* * Process any directory removals that have been committed. */ while ((dirrem = LIST_FIRST(&pagedep->pd_dirremhd)) != NULL) { LIST_REMOVE(dirrem, dm_next); dirrem->dm_dirinum = pagedep->pd_ino; add_to_worklist(&dirrem->dm_list); } /* * Free any directory additions that have been committed. */ while ((dap = LIST_FIRST(&pagedep->pd_pendinghd)) != NULL) free_diradd(dap); /* * Uncommitted directory entries must be restored. */ for (chgs = 0, i = 0; i < DAHASHSZ; i++) { for (dap = LIST_FIRST(&pagedep->pd_diraddhd[i]); dap; dap = nextdap) { nextdap = LIST_NEXT(dap, da_pdlist); if (dap->da_state & ATTACHED) panic("handle_written_filepage: attached"); ep = (struct direct *) ((char *)bp->b_data + dap->da_offset); ep->d_ino = dap->da_newinum; dap->da_state &= ~UNDONE; dap->da_state |= ATTACHED; chgs = 1; /* * If the inode referenced by the directory has * been written out, then the dependency can be * moved to the pending list. */ if ((dap->da_state & ALLCOMPLETE) == ALLCOMPLETE) { LIST_REMOVE(dap, da_pdlist); LIST_INSERT_HEAD(&pagedep->pd_pendinghd, dap, da_pdlist); } } } /* * If there were any rollbacks in the directory, then it must be * marked dirty so that its will eventually get written back in * its correct form. */ if (chgs) { if ((bp->b_flags & B_DELWRI) == 0) stat_dir_entry++; bdirty(bp); } /* * If no dependencies remain, the pagedep will be freed. * Otherwise it will remain to update the page before it * is written back to disk. */ if (LIST_FIRST(&pagedep->pd_pendinghd) == 0) { for (i = 0; i < DAHASHSZ; i++) if (LIST_FIRST(&pagedep->pd_diraddhd[i]) != NULL) break; if (i == DAHASHSZ) { LIST_REMOVE(pagedep, pd_hash); WORKITEM_FREE(pagedep, D_PAGEDEP); return (0); } } return (1); } /* * Writing back in-core inode structures. * * The file system only accesses an inode's contents when it occupies an * "in-core" inode structure. These "in-core" structures are separate from * the page frames used to cache inode blocks. Only the latter are * transferred to/from the disk. So, when the updated contents of the * "in-core" inode structure are copied to the corresponding in-memory inode * block, the dependencies are also transferred. The following procedure is * called when copying a dirty "in-core" inode to a cached inode block. */ /* * Called when an inode is loaded from disk. If the effective link count * differed from the actual link count when it was last flushed, then we * need to ensure that the correct effective link count is put back. */ void softdep_load_inodeblock(ip) struct inode *ip; /* the "in_core" copy of the inode */ { struct inodedep *inodedep; /* * Check for alternate nlink count. */ ip->i_effnlink = ip->i_nlink; ACQUIRE_LOCK(&lk); if (inodedep_lookup(ip->i_fs, ip->i_number, 0, &inodedep) == 0) { FREE_LOCK(&lk); return; } ip->i_effnlink -= inodedep->id_nlinkdelta; FREE_LOCK(&lk); } /* * This routine is called just before the "in-core" inode * information is to be copied to the in-memory inode block. * Recall that an inode block contains several inodes. If * the force flag is set, then the dependencies will be * cleared so that the update can always be made. Note that * the buffer is locked when this routine is called, so we * will never be in the middle of writing the inode block * to disk. */ void softdep_update_inodeblock(ip, bp, waitfor) struct inode *ip; /* the "in_core" copy of the inode */ struct buf *bp; /* the buffer containing the inode block */ int waitfor; /* nonzero => update must be allowed */ { struct inodedep *inodedep; struct worklist *wk; int error, gotit; /* * If the effective link count is not equal to the actual link * count, then we must track the difference in an inodedep while * the inode is (potentially) tossed out of the cache. Otherwise, * if there is no existing inodedep, then there are no dependencies * to track. */ ACQUIRE_LOCK(&lk); if (inodedep_lookup(ip->i_fs, ip->i_number, 0, &inodedep) == 0) { if (ip->i_effnlink != ip->i_nlink) panic("softdep_update_inodeblock: bad link count"); FREE_LOCK(&lk); return; } if (inodedep->id_nlinkdelta != ip->i_nlink - ip->i_effnlink) panic("softdep_update_inodeblock: bad delta"); /* * Changes have been initiated. Anything depending on these * changes cannot occur until this inode has been written. */ inodedep->id_state &= ~COMPLETE; if ((inodedep->id_state & ONWORKLIST) == 0) WORKLIST_INSERT(&bp->b_dep, &inodedep->id_list); /* * Any new dependencies associated with the incore inode must * now be moved to the list associated with the buffer holding * the in-memory copy of the inode. Once merged process any * allocdirects that are completed by the merger. */ merge_inode_lists(inodedep); if (TAILQ_FIRST(&inodedep->id_inoupdt) != NULL) handle_allocdirect_partdone(TAILQ_FIRST(&inodedep->id_inoupdt)); /* * Now that the inode has been pushed into the buffer, the * operations dependent on the inode being written to disk * can be moved to the id_bufwait so that they will be * processed when the buffer I/O completes. */ while ((wk = LIST_FIRST(&inodedep->id_inowait)) != NULL) { WORKLIST_REMOVE(wk); WORKLIST_INSERT(&inodedep->id_bufwait, wk); } /* * Newly allocated inodes cannot be written until the bitmap * that allocates them have been written (indicated by * DEPCOMPLETE being set in id_state). If we are doing a * forced sync (e.g., an fsync on a file), we force the bitmap * to be written so that the update can be done. */ if ((inodedep->id_state & DEPCOMPLETE) != 0 || waitfor == 0) { FREE_LOCK(&lk); return; } gotit = getdirtybuf(&inodedep->id_buf, MNT_WAIT); FREE_LOCK(&lk); if (gotit && (error = BUF_WRITE(inodedep->id_buf)) != 0) softdep_error("softdep_update_inodeblock: bwrite", error); if ((inodedep->id_state & DEPCOMPLETE) == 0) panic("softdep_update_inodeblock: update failed"); } /* * Merge the new inode dependency list (id_newinoupdt) into the old * inode dependency list (id_inoupdt). This routine must be called * with splbio interrupts blocked. */ static void merge_inode_lists(inodedep) struct inodedep *inodedep; { struct allocdirect *listadp, *newadp; newadp = TAILQ_FIRST(&inodedep->id_newinoupdt); for (listadp = TAILQ_FIRST(&inodedep->id_inoupdt); listadp && newadp;) { if (listadp->ad_lbn < newadp->ad_lbn) { listadp = TAILQ_NEXT(listadp, ad_next); continue; } TAILQ_REMOVE(&inodedep->id_newinoupdt, newadp, ad_next); TAILQ_INSERT_BEFORE(listadp, newadp, ad_next); if (listadp->ad_lbn == newadp->ad_lbn) { allocdirect_merge(&inodedep->id_inoupdt, newadp, listadp); listadp = newadp; } newadp = TAILQ_FIRST(&inodedep->id_newinoupdt); } while ((newadp = TAILQ_FIRST(&inodedep->id_newinoupdt)) != NULL) { TAILQ_REMOVE(&inodedep->id_newinoupdt, newadp, ad_next); TAILQ_INSERT_TAIL(&inodedep->id_inoupdt, newadp, ad_next); } } /* * If we are doing an fsync, then we must ensure that any directory * entries for the inode have been written after the inode gets to disk. */ int softdep_fsync(vp) struct vnode *vp; /* the "in_core" copy of the inode */ { struct inodedep *inodedep; struct pagedep *pagedep; struct worklist *wk; struct diradd *dap; struct mount *mnt; struct vnode *pvp; struct inode *ip; struct buf *bp; struct fs *fs; struct proc *p = CURPROC; /* XXX */ int error, flushparent; ino_t parentino; ufs_lbn_t lbn; ip = VTOI(vp); fs = ip->i_fs; ACQUIRE_LOCK(&lk); if (inodedep_lookup(fs, ip->i_number, 0, &inodedep) == 0) { FREE_LOCK(&lk); return (0); } if (LIST_FIRST(&inodedep->id_inowait) != NULL || LIST_FIRST(&inodedep->id_bufwait) != NULL || TAILQ_FIRST(&inodedep->id_inoupdt) != NULL || TAILQ_FIRST(&inodedep->id_newinoupdt) != NULL) panic("softdep_fsync: pending ops"); for (error = 0, flushparent = 0; ; ) { if ((wk = LIST_FIRST(&inodedep->id_pendinghd)) == NULL) break; if (wk->wk_type != D_DIRADD) panic("softdep_fsync: Unexpected type %s", TYPENAME(wk->wk_type)); dap = WK_DIRADD(wk); /* * Flush our parent if this directory entry * has a MKDIR_PARENT dependency. */ if (dap->da_state & DIRCHG) pagedep = dap->da_previous->dm_pagedep; else pagedep = dap->da_pagedep; mnt = pagedep->pd_mnt; parentino = pagedep->pd_ino; lbn = pagedep->pd_lbn; if ((dap->da_state & (MKDIR_BODY | COMPLETE)) != COMPLETE) panic("softdep_fsync: dirty"); flushparent = dap->da_state & MKDIR_PARENT; /* * If we are being fsync'ed as part of vgone'ing this vnode, * then we will not be able to release and recover the * vnode below, so we just have to give up on writing its * directory entry out. It will eventually be written, just * not now, but then the user was not asking to have it * written, so we are not breaking any promises. */ if (vp->v_flag & VXLOCK) break; /* * We prevent deadlock by always fetching inodes from the * root, moving down the directory tree. Thus, when fetching * our parent directory, we must unlock ourselves before * requesting the lock on our parent. See the comment in * ufs_lookup for details on possible races. */ FREE_LOCK(&lk); VOP_UNLOCK(vp, 0, p); error = VFS_VGET(mnt, parentino, &pvp); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); if (error != 0) return (error); if (flushparent) { if ((error = UFS_UPDATE(pvp, 1)) != 0) { vput(pvp); return (error); } } /* * Flush directory page containing the inode's name. */ error = bread(pvp, lbn, blksize(fs, VTOI(pvp), lbn), p->p_ucred, &bp); if (error == 0) error = BUF_WRITE(bp); vput(pvp); if (error != 0) return (error); ACQUIRE_LOCK(&lk); if (inodedep_lookup(fs, ip->i_number, 0, &inodedep) == 0) break; } FREE_LOCK(&lk); return (0); } /* * Flush all the dirty bitmaps associated with the block device * before flushing the rest of the dirty blocks so as to reduce * the number of dependencies that will have to be rolled back. */ void softdep_fsync_mountdev(vp) struct vnode *vp; { struct buf *bp, *nbp; struct worklist *wk; if (!vn_isdisk(vp, NULL)) panic("softdep_fsync_mountdev: vnode not a disk"); ACQUIRE_LOCK(&lk); for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { nbp = TAILQ_NEXT(bp, b_vnbufs); /* * If it is already scheduled, skip to the next buffer. */ if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) continue; if ((bp->b_flags & B_DELWRI) == 0) panic("softdep_fsync_mountdev: not dirty"); /* * We are only interested in bitmaps with outstanding * dependencies. */ if ((wk = LIST_FIRST(&bp->b_dep)) == NULL || wk->wk_type != D_BMSAFEMAP || (bp->b_xflags & BX_BKGRDINPROG)) { BUF_UNLOCK(bp); continue; } bremfree(bp); FREE_LOCK(&lk); (void) bawrite(bp); ACQUIRE_LOCK(&lk); /* * Since we may have slept during the I/O, we need * to start from a known point. */ nbp = TAILQ_FIRST(&vp->v_dirtyblkhd); } drain_output(vp, 1); FREE_LOCK(&lk); } /* * This routine is called when we are trying to synchronously flush a * file. This routine must eliminate any filesystem metadata dependencies * so that the syncing routine can succeed by pushing the dirty blocks * associated with the file. If any I/O errors occur, they are returned. */ int softdep_sync_metadata(ap) struct vop_fsync_args /* { struct vnode *a_vp; struct ucred *a_cred; int a_waitfor; struct proc *a_p; } */ *ap; { struct vnode *vp = ap->a_vp; struct pagedep *pagedep; struct allocdirect *adp; struct allocindir *aip; struct buf *bp, *nbp; struct worklist *wk; int i, error, waitfor; /* * Check whether this vnode is involved in a filesystem * that is doing soft dependency processing. */ if (!vn_isdisk(vp, NULL)) { if (!DOINGSOFTDEP(vp)) return (0); } else if (vp->v_rdev->si_mountpoint == NULL || (vp->v_rdev->si_mountpoint->mnt_flag & MNT_SOFTDEP) == 0) return (0); /* * Ensure that any direct block dependencies have been cleared. */ ACQUIRE_LOCK(&lk); if ((error = flush_inodedep_deps(VTOI(vp)->i_fs, VTOI(vp)->i_number))) { FREE_LOCK(&lk); return (error); } /* * For most files, the only metadata dependencies are the * cylinder group maps that allocate their inode or blocks. * The block allocation dependencies can be found by traversing * the dependency lists for any buffers that remain on their * dirty buffer list. The inode allocation dependency will * be resolved when the inode is updated with MNT_WAIT. * This work is done in two passes. The first pass grabs most * of the buffers and begins asynchronously writing them. The * only way to wait for these asynchronous writes is to sleep * on the filesystem vnode which may stay busy for a long time * if the filesystem is active. So, instead, we make a second * pass over the dependencies blocking on each write. In the * usual case we will be blocking against a write that we * initiated, so when it is done the dependency will have been * resolved. Thus the second pass is expected to end quickly. */ waitfor = MNT_NOWAIT; top: if (getdirtybuf(&TAILQ_FIRST(&vp->v_dirtyblkhd), MNT_WAIT) == 0) { FREE_LOCK(&lk); return (0); } bp = TAILQ_FIRST(&vp->v_dirtyblkhd); loop: /* * As we hold the buffer locked, none of its dependencies * will disappear. */ for (wk = LIST_FIRST(&bp->b_dep); wk; wk = LIST_NEXT(wk, wk_list)) { switch (wk->wk_type) { case D_ALLOCDIRECT: adp = WK_ALLOCDIRECT(wk); if (adp->ad_state & DEPCOMPLETE) break; nbp = adp->ad_buf; if (getdirtybuf(&nbp, waitfor) == 0) break; FREE_LOCK(&lk); if (waitfor == MNT_NOWAIT) { bawrite(nbp); } else if ((error = BUF_WRITE(nbp)) != 0) { bawrite(bp); return (error); } ACQUIRE_LOCK(&lk); break; case D_ALLOCINDIR: aip = WK_ALLOCINDIR(wk); if (aip->ai_state & DEPCOMPLETE) break; nbp = aip->ai_buf; if (getdirtybuf(&nbp, waitfor) == 0) break; FREE_LOCK(&lk); if (waitfor == MNT_NOWAIT) { bawrite(nbp); } else if ((error = BUF_WRITE(nbp)) != 0) { bawrite(bp); return (error); } ACQUIRE_LOCK(&lk); break; case D_INDIRDEP: restart: for (aip = LIST_FIRST(&WK_INDIRDEP(wk)->ir_deplisthd); aip; aip = LIST_NEXT(aip, ai_next)) { if (aip->ai_state & DEPCOMPLETE) continue; nbp = aip->ai_buf; if (getdirtybuf(&nbp, MNT_WAIT) == 0) goto restart; FREE_LOCK(&lk); if ((error = BUF_WRITE(nbp)) != 0) { bawrite(bp); return (error); } ACQUIRE_LOCK(&lk); goto restart; } break; case D_INODEDEP: if ((error = flush_inodedep_deps(WK_INODEDEP(wk)->id_fs, WK_INODEDEP(wk)->id_ino)) != 0) { FREE_LOCK(&lk); bawrite(bp); return (error); } break; case D_PAGEDEP: /* * We are trying to sync a directory that may * have dependencies on both its own metadata * and/or dependencies on the inodes of any * recently allocated files. We walk its diradd * lists pushing out the associated inode. */ pagedep = WK_PAGEDEP(wk); for (i = 0; i < DAHASHSZ; i++) { if (LIST_FIRST(&pagedep->pd_diraddhd[i]) == 0) continue; if ((error = flush_pagedep_deps(vp, pagedep->pd_mnt, &pagedep->pd_diraddhd[i]))) { FREE_LOCK(&lk); bawrite(bp); return (error); } } break; case D_MKDIR: /* * This case should never happen if the vnode has * been properly sync'ed. However, if this function * is used at a place where the vnode has not yet * been sync'ed, this dependency can show up. So, * rather than panic, just flush it. */ nbp = WK_MKDIR(wk)->md_buf; if (getdirtybuf(&nbp, waitfor) == 0) break; FREE_LOCK(&lk); if (waitfor == MNT_NOWAIT) { bawrite(nbp); } else if ((error = BUF_WRITE(nbp)) != 0) { bawrite(bp); return (error); } ACQUIRE_LOCK(&lk); break; case D_BMSAFEMAP: /* * This case should never happen if the vnode has * been properly sync'ed. However, if this function * is used at a place where the vnode has not yet * been sync'ed, this dependency can show up. So, * rather than panic, just flush it. */ nbp = WK_BMSAFEMAP(wk)->sm_buf; if (getdirtybuf(&nbp, waitfor) == 0) break; FREE_LOCK(&lk); if (waitfor == MNT_NOWAIT) { bawrite(nbp); } else if ((error = BUF_WRITE(nbp)) != 0) { bawrite(bp); return (error); } ACQUIRE_LOCK(&lk); break; default: panic("softdep_sync_metadata: Unknown type %s", TYPENAME(wk->wk_type)); /* NOTREACHED */ } } (void) getdirtybuf(&TAILQ_NEXT(bp, b_vnbufs), MNT_WAIT); nbp = TAILQ_NEXT(bp, b_vnbufs); FREE_LOCK(&lk); bawrite(bp); ACQUIRE_LOCK(&lk); if (nbp != NULL) { bp = nbp; goto loop; } /* * We must wait for any I/O in progress to finish so that * all potential buffers on the dirty list will be visible. * Once they are all there, proceed with the second pass * which will wait for the I/O as per above. */ drain_output(vp, 1); /* * The brief unlock is to allow any pent up dependency * processing to be done. */ if (waitfor == MNT_NOWAIT) { waitfor = MNT_WAIT; FREE_LOCK(&lk); ACQUIRE_LOCK(&lk); goto top; } /* * If we have managed to get rid of all the dirty buffers, * then we are done. For certain directories and block * devices, we may need to do further work. */ if (TAILQ_FIRST(&vp->v_dirtyblkhd) == NULL) { FREE_LOCK(&lk); return (0); } FREE_LOCK(&lk); /* * If we are trying to sync a block device, some of its buffers may * contain metadata that cannot be written until the contents of some * partially written files have been written to disk. The only easy * way to accomplish this is to sync the entire filesystem (luckily * this happens rarely). */ if (vn_isdisk(vp, NULL) && vp->v_rdev->si_mountpoint && !VOP_ISLOCKED(vp, NULL) && (error = VFS_SYNC(vp->v_rdev->si_mountpoint, MNT_WAIT, ap->a_cred, ap->a_p)) != 0) return (error); return (0); } /* * Flush the dependencies associated with an inodedep. * Called with splbio blocked. */ static int flush_inodedep_deps(fs, ino) struct fs *fs; ino_t ino; { struct inodedep *inodedep; struct allocdirect *adp; int error, waitfor; struct buf *bp; /* * This work is done in two passes. The first pass grabs most * of the buffers and begins asynchronously writing them. The * only way to wait for these asynchronous writes is to sleep * on the filesystem vnode which may stay busy for a long time * if the filesystem is active. So, instead, we make a second * pass over the dependencies blocking on each write. In the * usual case we will be blocking against a write that we * initiated, so when it is done the dependency will have been * resolved. Thus the second pass is expected to end quickly. * We give a brief window at the top of the loop to allow * any pending I/O to complete. */ for (waitfor = MNT_NOWAIT; ; ) { FREE_LOCK(&lk); ACQUIRE_LOCK(&lk); if (inodedep_lookup(fs, ino, 0, &inodedep) == 0) return (0); for (adp = TAILQ_FIRST(&inodedep->id_inoupdt); adp; adp = TAILQ_NEXT(adp, ad_next)) { if (adp->ad_state & DEPCOMPLETE) continue; bp = adp->ad_buf; if (getdirtybuf(&bp, waitfor) == 0) { if (waitfor == MNT_NOWAIT) continue; break; } FREE_LOCK(&lk); if (waitfor == MNT_NOWAIT) { bawrite(bp); } else if ((error = BUF_WRITE(bp)) != 0) { ACQUIRE_LOCK(&lk); return (error); } ACQUIRE_LOCK(&lk); break; } if (adp != NULL) continue; for (adp = TAILQ_FIRST(&inodedep->id_newinoupdt); adp; adp = TAILQ_NEXT(adp, ad_next)) { if (adp->ad_state & DEPCOMPLETE) continue; bp = adp->ad_buf; if (getdirtybuf(&bp, waitfor) == 0) { if (waitfor == MNT_NOWAIT) continue; break; } FREE_LOCK(&lk); if (waitfor == MNT_NOWAIT) { bawrite(bp); } else if ((error = BUF_WRITE(bp)) != 0) { ACQUIRE_LOCK(&lk); return (error); } ACQUIRE_LOCK(&lk); break; } if (adp != NULL) continue; /* * If pass2, we are done, otherwise do pass 2. */ if (waitfor == MNT_WAIT) break; waitfor = MNT_WAIT; } /* * Try freeing inodedep in case all dependencies have been removed. */ if (inodedep_lookup(fs, ino, 0, &inodedep) != 0) (void) free_inodedep(inodedep); return (0); } /* * Eliminate a pagedep dependency by flushing out all its diradd dependencies. * Called with splbio blocked. */ static int flush_pagedep_deps(pvp, mp, diraddhdp) struct vnode *pvp; struct mount *mp; struct diraddhd *diraddhdp; { struct proc *p = CURPROC; /* XXX */ struct inodedep *inodedep; struct ufsmount *ump; struct diradd *dap; struct vnode *vp; int gotit, error = 0; struct buf *bp; ino_t inum; ump = VFSTOUFS(mp); while ((dap = LIST_FIRST(diraddhdp)) != NULL) { /* * Flush ourselves if this directory entry * has a MKDIR_PARENT dependency. */ if (dap->da_state & MKDIR_PARENT) { FREE_LOCK(&lk); if ((error = UFS_UPDATE(pvp, 1)) != 0) break; ACQUIRE_LOCK(&lk); /* * If that cleared dependencies, go on to next. */ if (dap != LIST_FIRST(diraddhdp)) continue; if (dap->da_state & MKDIR_PARENT) panic("flush_pagedep_deps: MKDIR_PARENT"); } /* * A newly allocated directory must have its "." and * ".." entries written out before its name can be * committed in its parent. We do not want or need * the full semantics of a synchronous VOP_FSYNC as * that may end up here again, once for each directory * level in the filesystem. Instead, we push the blocks * and wait for them to clear. We have to fsync twice * because the first call may choose to defer blocks * that still have dependencies, but deferral will * happen at most once. */ inum = dap->da_newinum; if (dap->da_state & MKDIR_BODY) { FREE_LOCK(&lk); if ((error = VFS_VGET(mp, inum, &vp)) != 0) break; if ((error=VOP_FSYNC(vp, p->p_ucred, MNT_NOWAIT, p)) || (error=VOP_FSYNC(vp, p->p_ucred, MNT_NOWAIT, p))) { vput(vp); break; } drain_output(vp, 0); vput(vp); ACQUIRE_LOCK(&lk); /* * If that cleared dependencies, go on to next. */ if (dap != LIST_FIRST(diraddhdp)) continue; if (dap->da_state & MKDIR_BODY) panic("flush_pagedep_deps: MKDIR_BODY"); } /* * Flush the inode on which the directory entry depends. * Having accounted for MKDIR_PARENT and MKDIR_BODY above, * the only remaining dependency is that the updated inode * count must get pushed to disk. The inode has already * been pushed into its inode buffer (via VOP_UPDATE) at * the time of the reference count change. So we need only * locate that buffer, ensure that there will be no rollback * caused by a bitmap dependency, then write the inode buffer. */ if (inodedep_lookup(ump->um_fs, inum, 0, &inodedep) == 0) panic("flush_pagedep_deps: lost inode"); /* * If the inode still has bitmap dependencies, * push them to disk. */ if ((inodedep->id_state & DEPCOMPLETE) == 0) { gotit = getdirtybuf(&inodedep->id_buf, MNT_WAIT); FREE_LOCK(&lk); if (gotit && (error = BUF_WRITE(inodedep->id_buf)) != 0) break; ACQUIRE_LOCK(&lk); if (dap != LIST_FIRST(diraddhdp)) continue; } /* * If the inode is still sitting in a buffer waiting * to be written, push it to disk. */ FREE_LOCK(&lk); if ((error = bread(ump->um_devvp, fsbtodb(ump->um_fs, ino_to_fsba(ump->um_fs, inum)), (int)ump->um_fs->fs_bsize, NOCRED, &bp)) != 0) break; if ((error = BUF_WRITE(bp)) != 0) break; ACQUIRE_LOCK(&lk); /* * If we have failed to get rid of all the dependencies * then something is seriously wrong. */ if (dap == LIST_FIRST(diraddhdp)) panic("flush_pagedep_deps: flush failed"); } if (error) ACQUIRE_LOCK(&lk); return (error); } /* * A large burst of file addition or deletion activity can drive the * memory load excessively high. First attempt to slow things down * using the techniques below. If that fails, this routine requests * the offending operations to fall back to running synchronously * until the memory load returns to a reasonable level. */ int softdep_slowdown(vp) struct vnode *vp; { int max_softdeps_hard; max_softdeps_hard = max_softdeps * 11 / 10; if (num_dirrem < max_softdeps_hard / 2 && num_inodedep < max_softdeps_hard) return (0); stat_sync_limit_hit += 1; return (1); } /* * If memory utilization has gotten too high, deliberately slow things * down and speed up the I/O processing. */ static int request_cleanup(resource, islocked) int resource; int islocked; { struct proc *p = CURPROC; /* * We never hold up the filesystem syncer process. */ if (p == filesys_syncer) return (0); /* * First check to see if the work list has gotten backlogged. * If it has, co-opt this process to help clean up two entries. * Because this process may hold inodes locked, we cannot * handle any remove requests that might block on a locked * inode as that could lead to deadlock. */ if (num_on_worklist > max_softdeps / 10) { process_worklist_item(NULL, LK_NOWAIT); process_worklist_item(NULL, LK_NOWAIT); stat_worklist_push += 2; return(0); } /* * Next, we attempt to speed up the syncer process. If that * is successful, then we allow the process to continue. */ if (speedup_syncer()) return(0); /* * If we are resource constrained on inode dependencies, try * flushing some dirty inodes. Otherwise, we are constrained * by file deletions, so try accelerating flushes of directories * with removal dependencies. We would like to do the cleanup * here, but we probably hold an inode locked at this point and * that might deadlock against one that we try to clean. So, * the best that we can do is request the syncer daemon to do * the cleanup for us. */ switch (resource) { case FLUSH_INODES: stat_ino_limit_push += 1; req_clear_inodedeps += 1; stat_countp = &stat_ino_limit_hit; break; case FLUSH_REMOVE: stat_blk_limit_push += 1; req_clear_remove += 1; stat_countp = &stat_blk_limit_hit; break; default: panic("request_cleanup: unknown type"); } /* * Hopefully the syncer daemon will catch up and awaken us. * We wait at most tickdelay before proceeding in any case. */ if (islocked == 0) ACQUIRE_LOCK(&lk); proc_waiting += 1; if (handle.callout == NULL) handle = timeout(pause_timer, 0, tickdelay > 2 ? tickdelay : 2); FREE_LOCK_INTERLOCKED(&lk); (void) tsleep((caddr_t)&proc_waiting, PPAUSE, "softupdate", 0); ACQUIRE_LOCK_INTERLOCKED(&lk); proc_waiting -= 1; if (islocked == 0) FREE_LOCK(&lk); return (1); } /* * Awaken processes pausing in request_cleanup and clear proc_waiting * to indicate that there is no longer a timer running. */ void pause_timer(arg) void *arg; { *stat_countp += 1; wakeup_one(&proc_waiting); if (proc_waiting > 0) handle = timeout(pause_timer, 0, tickdelay > 2 ? tickdelay : 2); else handle.callout = NULL; } /* * Flush out a directory with at least one removal dependency in an effort to * reduce the number of dirrem, freefile, and freeblks dependency structures. */ static void clear_remove(p) struct proc *p; { struct pagedep_hashhead *pagedephd; struct pagedep *pagedep; static int next = 0; struct mount *mp; struct vnode *vp; int error, cnt; ino_t ino; ACQUIRE_LOCK(&lk); for (cnt = 0; cnt < pagedep_hash; cnt++) { pagedephd = &pagedep_hashtbl[next++]; if (next >= pagedep_hash) next = 0; for (pagedep = LIST_FIRST(pagedephd); pagedep; pagedep = LIST_NEXT(pagedep, pd_hash)) { if (LIST_FIRST(&pagedep->pd_dirremhd) == NULL) continue; mp = pagedep->pd_mnt; ino = pagedep->pd_ino; FREE_LOCK(&lk); if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) continue; if ((error = VFS_VGET(mp, ino, &vp)) != 0) { softdep_error("clear_remove: vget", error); vn_finished_write(mp); return; } if ((error = VOP_FSYNC(vp, p->p_ucred, MNT_NOWAIT, p))) softdep_error("clear_remove: fsync", error); drain_output(vp, 0); vput(vp); vn_finished_write(mp); return; } } FREE_LOCK(&lk); } /* * Clear out a block of dirty inodes in an effort to reduce * the number of inodedep dependency structures. */ static void clear_inodedeps(p) struct proc *p; { struct inodedep_hashhead *inodedephd; struct inodedep *inodedep; static int next = 0; struct mount *mp; struct vnode *vp; struct fs *fs; int error, cnt; ino_t firstino, lastino, ino; ACQUIRE_LOCK(&lk); /* * Pick a random inode dependency to be cleared. * We will then gather up all the inodes in its block * that have dependencies and flush them out. */ for (cnt = 0; cnt < inodedep_hash; cnt++) { inodedephd = &inodedep_hashtbl[next++]; if (next >= inodedep_hash) next = 0; if ((inodedep = LIST_FIRST(inodedephd)) != NULL) break; } /* * Ugly code to find mount point given pointer to superblock. */ fs = inodedep->id_fs; TAILQ_FOREACH(mp, &mountlist, mnt_list) if ((mp->mnt_flag & MNT_SOFTDEP) && fs == VFSTOUFS(mp)->um_fs) break; /* * Find the last inode in the block with dependencies. */ firstino = inodedep->id_ino & ~(INOPB(fs) - 1); for (lastino = firstino + INOPB(fs) - 1; lastino > firstino; lastino--) if (inodedep_lookup(fs, lastino, 0, &inodedep) != 0) break; /* * Asynchronously push all but the last inode with dependencies. * Synchronously push the last inode with dependencies to ensure * that the inode block gets written to free up the inodedeps. */ for (ino = firstino; ino <= lastino; ino++) { if (inodedep_lookup(fs, ino, 0, &inodedep) == 0) continue; FREE_LOCK(&lk); if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) continue; if ((error = VFS_VGET(mp, ino, &vp)) != 0) { softdep_error("clear_inodedeps: vget", error); vn_finished_write(mp); return; } if (ino == lastino) { if ((error = VOP_FSYNC(vp, p->p_ucred, MNT_WAIT, p))) softdep_error("clear_inodedeps: fsync1", error); } else { if ((error = VOP_FSYNC(vp, p->p_ucred, MNT_NOWAIT, p))) softdep_error("clear_inodedeps: fsync2", error); drain_output(vp, 0); } vput(vp); vn_finished_write(mp); ACQUIRE_LOCK(&lk); } FREE_LOCK(&lk); } /* * Function to determine if the buffer has outstanding dependencies * that will cause a roll-back if the buffer is written. If wantcount * is set, return number of dependencies, otherwise just yes or no. */ static int softdep_count_dependencies(bp, wantcount) struct buf *bp; int wantcount; { struct worklist *wk; struct inodedep *inodedep; struct indirdep *indirdep; struct allocindir *aip; struct pagedep *pagedep; struct diradd *dap; int i, retval; retval = 0; ACQUIRE_LOCK(&lk); for (wk = LIST_FIRST(&bp->b_dep); wk; wk = LIST_NEXT(wk, wk_list)) { switch (wk->wk_type) { case D_INODEDEP: inodedep = WK_INODEDEP(wk); if ((inodedep->id_state & DEPCOMPLETE) == 0) { /* bitmap allocation dependency */ retval += 1; if (!wantcount) goto out; } if (TAILQ_FIRST(&inodedep->id_inoupdt)) { /* direct block pointer dependency */ retval += 1; if (!wantcount) goto out; } continue; case D_INDIRDEP: indirdep = WK_INDIRDEP(wk); for (aip = LIST_FIRST(&indirdep->ir_deplisthd); aip; aip = LIST_NEXT(aip, ai_next)) { /* indirect block pointer dependency */ retval += 1; if (!wantcount) goto out; } continue; case D_PAGEDEP: pagedep = WK_PAGEDEP(wk); for (i = 0; i < DAHASHSZ; i++) { for (dap = LIST_FIRST(&pagedep->pd_diraddhd[i]); dap; dap = LIST_NEXT(dap, da_pdlist)) { /* directory entry dependency */ retval += 1; if (!wantcount) goto out; } } continue; case D_BMSAFEMAP: case D_ALLOCDIRECT: case D_ALLOCINDIR: case D_MKDIR: /* never a dependency on these blocks */ continue; default: panic("softdep_check_for_rollback: Unexpected type %s", TYPENAME(wk->wk_type)); /* NOTREACHED */ } } out: FREE_LOCK(&lk); return retval; } /* * Acquire exclusive access to a buffer. * Must be called with splbio blocked. * Return 1 if buffer was acquired. */ static int getdirtybuf(bpp, waitfor) struct buf **bpp; int waitfor; { struct buf *bp; for (;;) { if ((bp = *bpp) == NULL) return (0); if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT) == 0) { if ((bp->b_xflags & BX_BKGRDINPROG) == 0) break; BUF_UNLOCK(bp); if (waitfor != MNT_WAIT) return (0); bp->b_xflags |= BX_BKGRDWAIT; FREE_LOCK_INTERLOCKED(&lk); tsleep(&bp->b_xflags, PRIBIO, "getbuf", 0); ACQUIRE_LOCK_INTERLOCKED(&lk); continue; } if (waitfor != MNT_WAIT) return (0); FREE_LOCK_INTERLOCKED(&lk); if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_SLEEPFAIL) != ENOLCK) panic("getdirtybuf: inconsistent lock"); ACQUIRE_LOCK_INTERLOCKED(&lk); } if ((bp->b_flags & B_DELWRI) == 0) { BUF_UNLOCK(bp); return (0); } bremfree(bp); return (1); } /* * Wait for pending output on a vnode to complete. * Must be called with vnode locked. */ static void drain_output(vp, islocked) struct vnode *vp; int islocked; { if (!islocked) ACQUIRE_LOCK(&lk); while (vp->v_numoutput) { vp->v_flag |= VBWAIT; FREE_LOCK_INTERLOCKED(&lk); tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "drainvp", 0); ACQUIRE_LOCK_INTERLOCKED(&lk); } if (!islocked) FREE_LOCK(&lk); } /* * Called whenever a buffer that is being invalidated or reallocated * contains dependencies. This should only happen if an I/O error has * occurred. The routine is called with the buffer locked. */ static void softdep_deallocate_dependencies(bp) struct buf *bp; { if ((bp->b_ioflags & BIO_ERROR) == 0) panic("softdep_deallocate_dependencies: dangling deps"); softdep_error(bp->b_vp->v_mount->mnt_stat.f_mntonname, bp->b_error); panic("softdep_deallocate_dependencies: unrecovered I/O error"); } /* * Function to handle asynchronous write errors in the filesystem. */ void softdep_error(func, error) char *func; int error; { /* XXX should do something better! */ printf("%s: got error %d while accessing filesystem\n", func, error); }