From 1cedd6dfaca4c0de0c1c02988b179b8040cd5815 Mon Sep 17 00:00:00 2001 From: Alan Somers Date: Sun, 31 Mar 2019 03:19:10 +0000 Subject: [PATCH] fusefs: replace the fufh table with a linked list The FUSE protocol allows each open file descriptor to have a unique file handle. On FreeBSD, these file handles must all be stored in the vnode. The old method (also used by OSX and OpenBSD) is to store them all in a small array. But that limits the total number that can be stored. This commit replaces the array with a linked list (a technique also used by Illumos). There is not yet any change in functionality, but this is the first step to fixing several bugs. PR: 236329, 236340, 236381, 236560, 236844 Discussed with: cem Sponsored by: The FreeBSD Foundation --- sys/fs/fuse/fuse_file.c | 62 ++++++++++++++++++------------------- sys/fs/fuse/fuse_file.h | 17 ++++++++-- sys/fs/fuse/fuse_internal.c | 10 ++---- sys/fs/fuse/fuse_node.c | 10 +++--- sys/fs/fuse/fuse_node.h | 3 +- sys/fs/fuse/fuse_vnops.c | 7 ++--- 6 files changed, 55 insertions(+), 54 deletions(-) diff --git a/sys/fs/fuse/fuse_file.c b/sys/fs/fuse/fuse_file.c index 198dfc415719..8d893a73a17c 100644 --- a/sys/fs/fuse/fuse_file.c +++ b/sys/fs/fuse/fuse_file.c @@ -82,6 +82,8 @@ __FBSDID("$FreeBSD$"); #include "fuse_ipc.h" #include "fuse_node.h" +MALLOC_DEFINE(M_FUSE_FILEHANDLE, "fuse_filefilehandle", "FUSE file handle"); + SDT_PROVIDER_DECLARE(fuse); /* * Fuse trace probe: @@ -157,16 +159,14 @@ fuse_filehandle_close(struct vnode *vp, fufh_type_t fufh_type, { struct fuse_dispatcher fdi; struct fuse_release_in *fri; - struct fuse_vnode_data *fvdat = VTOFUD(vp); struct fuse_filehandle *fufh = NULL; int err = 0; int op = FUSE_RELEASE; - fufh = &(fvdat->fufh[fufh_type]); - if (!FUFH_IS_VALID(fufh)) { - panic("FUSE: filehandle_put called on invalid fufh (type=%d)", - fufh_type); + if (fuse_filehandle_get(vp, fufh_type, &fufh)) { + panic("FUSE: fuse_filehandle_close called on invalid fufh " + "(type=%d)", fufh_type); /* NOTREACHED */ } if (fuse_isdeadfs(vp)) { @@ -185,8 +185,8 @@ fuse_filehandle_close(struct vnode *vp, fufh_type_t fufh_type, out: atomic_subtract_acq_int(&fuse_fh_count, 1); - fufh->fh_id = (uint64_t)-1; - fufh->fh_type = FUFH_INVALID; + LIST_REMOVE(fufh, next); + free(fufh, M_FUSE_FILEHANDLE); return err; } @@ -194,31 +194,22 @@ out: int fuse_filehandle_valid(struct vnode *vp, fufh_type_t fufh_type) { - struct fuse_vnode_data *fvdat = VTOFUD(vp); - struct fuse_filehandle *fufh; - - fufh = &(fvdat->fufh[fufh_type]); - return FUFH_IS_VALID(fufh); + return (0 == fuse_filehandle_get(vp, fufh_type, NULL)); } /* * Check for a valid file handle, first the type requested, but if that * isn't valid, try for FUFH_RDWR. * Return the FUFH type that is valid or FUFH_INVALID if there are none. - * This is a variant of fuse_filehandle_vaild() analogous to + * This is a variant of fuse_filehandle_valid() analogous to * fuse_filehandle_getrw(). */ fufh_type_t fuse_filehandle_validrw(struct vnode *vp, fufh_type_t fufh_type) { - struct fuse_vnode_data *fvdat = VTOFUD(vp); - struct fuse_filehandle *fufh; - - fufh = &fvdat->fufh[fufh_type]; - if (FUFH_IS_VALID(fufh) != 0) + if (fuse_filehandle_get(vp, fufh_type, NULL) == 0) return (fufh_type); - fufh = &fvdat->fufh[FUFH_RDWR]; - if (FUFH_IS_VALID(fufh) != 0) + if (fuse_filehandle_get(vp, FUFH_RDWR, NULL) == 0) return (FUFH_RDWR); return (FUFH_INVALID); } @@ -230,8 +221,14 @@ fuse_filehandle_get(struct vnode *vp, fufh_type_t fufh_type, struct fuse_vnode_data *fvdat = VTOFUD(vp); struct fuse_filehandle *fufh; - fufh = &(fvdat->fufh[fufh_type]); - if (!FUFH_IS_VALID(fufh)) + /* TODO: Find a list entry with the same mode, pid, gid, and uid */ + /* Fallback: find a list entry with the right mode */ + LIST_FOREACH(fufh, &fvdat->handles, next) { + if (fufh->mode == fufh_type) + break; + } + + if (fufh == NULL) return EBADF; if (fufhp != NULL) *fufhp = fufh; @@ -242,14 +239,12 @@ int fuse_filehandle_getrw(struct vnode *vp, fufh_type_t fufh_type, struct fuse_filehandle **fufhp) { - struct fuse_vnode_data *fvdat = VTOFUD(vp); - struct fuse_filehandle *fufh; + int err; - fufh = &(fvdat->fufh[fufh_type]); - if (!FUFH_IS_VALID(fufh)) { - fufh_type = FUFH_RDWR; - } - return fuse_filehandle_get(vp, fufh_type, fufhp); + err = fuse_filehandle_get(vp, fufh_type, fufhp); + if (err) + err = fuse_filehandle_get(vp, FUFH_RDWR, fufhp); + return err; } void @@ -259,13 +254,16 @@ fuse_filehandle_init(struct vnode *vp, fufh_type_t fufh_type, struct fuse_vnode_data *fvdat = VTOFUD(vp); struct fuse_filehandle *fufh; - fufh = &(fvdat->fufh[fufh_type]); - MPASS(!FUFH_IS_VALID(fufh)); + fufh = malloc(sizeof(struct fuse_filehandle), M_FUSE_FILEHANDLE, + M_WAITOK); + MPASS(fufh != NULL); fufh->fh_id = fh_id; - fufh->fh_type = fufh_type; + fufh->mode = fufh_type; + /* TODO: initialize fufh credentials and open flags */ if (!FUFH_IS_VALID(fufh)) { panic("FUSE: init: invalid filehandle id (type=%d)", fufh_type); } + LIST_INSERT_HEAD(&fvdat->handles, fufh, next); if (fufhp != NULL) *fufhp = fufh; diff --git a/sys/fs/fuse/fuse_file.h b/sys/fs/fuse/fuse_file.h index 7bd0ad31427d..916cc70bfa77 100644 --- a/sys/fs/fuse/fuse_file.h +++ b/sys/fs/fuse/fuse_file.h @@ -78,11 +78,24 @@ _Static_assert(FUFH_WRONLY == O_WRONLY, "WRONLY"); _Static_assert(FUFH_RDWR == O_RDWR, "RDWR"); struct fuse_filehandle { + LIST_ENTRY(fuse_filehandle) next; + + /* The filehandle returned by FUSE_OPEN */ uint64_t fh_id; - fufh_type_t fh_type; + + /* flags returned by FUSE_OPEN */ + uint32_t fuse_open_flags; + + /* The mode used to open(2) the file (using O_RDONLY, not FREAD) */ + uint32_t mode; + + /* Credentials used to open the file */ + gid_t gid; + pid_t pid; + uid_t uid; }; -#define FUFH_IS_VALID(f) ((f)->fh_type != FUFH_INVALID) +#define FUFH_IS_VALID(f) ((f)->mode != FUFH_INVALID) static inline fufh_type_t fuse_filehandle_xlate_from_fflags(int fflags) diff --git a/sys/fs/fuse/fuse_internal.c b/sys/fs/fuse/fuse_internal.c index 2a5a409b2ec7..a02b446c6a1f 100644 --- a/sys/fs/fuse/fuse_internal.c +++ b/sys/fs/fuse/fuse_internal.c @@ -285,7 +285,6 @@ fuse_internal_fsync(struct vnode *vp, struct fuse_fsync_in *ffsi; struct fuse_dispatcher fdi; struct fuse_filehandle *fufh; - struct fuse_vnode_data *fvdat = VTOFUD(vp); int op = FUSE_FSYNC; int type = 0; int err = 0; @@ -295,8 +294,7 @@ fuse_internal_fsync(struct vnode *vp, return 0; } for (type = 0; type < FUFH_MAXTYPE; type++) { - fufh = &(fvdat->fufh[type]); - if (FUFH_IS_VALID(fufh)) { + if (fuse_filehandle_get(vp, type, &fufh) == 0) { if (vnode_isdir(vp)) { op = FUSE_FSYNCDIR; } @@ -454,11 +452,7 @@ fuse_internal_remove(struct vnode *dvp, enum fuse_opcode op) { struct fuse_dispatcher fdi; - struct fuse_vnode_data *fvdat; - int err; - - err = 0; - fvdat = VTOFUD(vp); + int err = 0; fdisp_init(&fdi, cnp->cn_namelen + 1); fdisp_make_vp(&fdi, op, dvp, cnp->cn_thread, cnp->cn_cred); diff --git a/sys/fs/fuse/fuse_node.c b/sys/fs/fuse/fuse_node.c index ad6a2619e812..83136c0a5aa2 100644 --- a/sys/fs/fuse/fuse_node.c +++ b/sys/fs/fuse/fuse_node.c @@ -174,9 +174,8 @@ static void fuse_vnode_init(struct vnode *vp, struct fuse_vnode_data *fvdat, uint64_t nodeid, enum vtype vtyp) { - int i; - fvdat->nid = nodeid; + LIST_INIT(&fvdat->handles); vattr_null(&fvdat->cached_attrs); if (nodeid == FUSE_ROOT_ID) { vp->v_vflag |= VV_ROOT; @@ -184,9 +183,6 @@ fuse_vnode_init(struct vnode *vp, struct fuse_vnode_data *fvdat, vp->v_type = vtyp; vp->v_data = fvdat; - for (i = 0; i < FUFH_MAXTYPE; i++) - fvdat->fufh[i].fh_type = FUFH_INVALID; - atomic_add_acq_int(&fuse_node_count, 1); } @@ -196,6 +192,8 @@ fuse_vnode_destroy(struct vnode *vp) struct fuse_vnode_data *fvdat = vp->v_data; vp->v_data = NULL; + KASSERT(LIST_EMPTY(&fvdat->handles), + ("Destroying fuse vnode with open files!")); free(fvdat, M_FUSEVN); atomic_subtract_acq_int(&fuse_node_count, 1); @@ -314,7 +312,7 @@ void fuse_vnode_open(struct vnode *vp, int32_t fuse_open_flags, struct thread *td) { /* - * Funcation is called for every vnode open. + * Function is called for every vnode open. * Merge fuse_open_flags it may be 0 */ /* diff --git a/sys/fs/fuse/fuse_node.h b/sys/fs/fuse/fuse_node.h index e87cf88aa615..4c1b4ea3a513 100644 --- a/sys/fs/fuse/fuse_node.h +++ b/sys/fs/fuse/fuse_node.h @@ -80,7 +80,8 @@ struct fuse_vnode_data { uint64_t parent_nid; /** I/O **/ - struct fuse_filehandle fufh[FUFH_MAXTYPE]; + /* List of file data for each of the vnode's open file descriptors */ + LIST_HEAD(, fuse_filehandle) handles; /** flags **/ uint32_t flag; diff --git a/sys/fs/fuse/fuse_vnops.c b/sys/fs/fuse/fuse_vnops.c index 56246c05f918..2a957be2f2ed 100644 --- a/sys/fs/fuse/fuse_vnops.c +++ b/sys/fs/fuse/fuse_vnops.c @@ -606,8 +606,7 @@ fuse_vnop_inactive(struct vop_inactive_args *ap) int type, need_flush = 1; for (type = 0; type < FUFH_MAXTYPE; type++) { - fufh = &(fvdat->fufh[type]); - if (FUFH_IS_VALID(fufh)) { + if (!fuse_filehandle_get(vp, type, &fufh)) { if (need_flush && vp->v_type == VREG) { if ((VTOFUD(vp)->flag & FN_SIZECHANGE) != 0) { fuse_vnode_savesize(vp, NULL); @@ -1396,7 +1395,6 @@ fuse_vnop_reclaim(struct vop_reclaim_args *ap) struct thread *td = ap->a_td; struct fuse_vnode_data *fvdat = VTOFUD(vp); - struct fuse_filehandle *fufh = NULL; int type; @@ -1404,8 +1402,7 @@ fuse_vnop_reclaim(struct vop_reclaim_args *ap) panic("FUSE: no vnode data during recycling"); } for (type = 0; type < FUFH_MAXTYPE; type++) { - fufh = &(fvdat->fufh[type]); - if (FUFH_IS_VALID(fufh)) { + if (fuse_filehandle_get(vp, type, NULL) == 0) { printf("FUSE: vnode being reclaimed but fufh (type=%d) is valid", type); fuse_filehandle_close(vp, type, td, NULL);