freebsd-dev/sys/fs/tmpfs/tmpfs_vfsops.c
Attilio Rao dfd233edd5 Remove the thread argument from the FSD (File-System Dependent) parts of
the VFS.  Now all the VFS_* functions and relating parts don't want the
context as long as it always refers to curthread.

In some points, in particular when dealing with VOPs and functions living
in the same namespace (eg. vflush) which still need to be converted,
pass curthread explicitly in order to retain the old behaviour.
Such loose ends will be fixed ASAP.

While here fix a bug: now, UFS_EXTATTR can be compiled alone without the
UFS_EXTATTR_AUTOSTART option.

VFS KPI is heavilly changed by this commit so thirdy parts modules needs
to be recompiled.  Bump __FreeBSD_version in order to signal such
situation.
2009-05-11 15:33:26 +00:00

465 lines
12 KiB
C

/* $NetBSD: tmpfs_vfsops.c,v 1.10 2005/12/11 12:24:29 christos Exp $ */
/*-
* Copyright (c) 2005 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Julio M. Merino Vidal, developed as part of Google's Summer of Code
* 2005 program.
*
* 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 THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``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 THE FOUNDATION OR CONTRIBUTORS
* 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.
*/
/*
* Efficient memory file system.
*
* tmpfs is a file system that uses NetBSD's virtual memory sub-system
* (the well-known UVM) to store file data and metadata in an efficient
* way. This means that it does not follow the structure of an on-disk
* file system because it simply does not need to. Instead, it uses
* memory-specific data structures and algorithms to automatically
* allocate and release resources.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/kernel.h>
#include <sys/stat.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_param.h>
#include <fs/tmpfs/tmpfs.h>
/*
* Default permission for root node
*/
#define TMPFS_DEFAULT_ROOT_MODE (S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH)
MALLOC_DEFINE(M_TMPFSMNT, "tmpfs mount", "tmpfs mount structures");
MALLOC_DEFINE(M_TMPFSNAME, "tmpfs name", "tmpfs file names");
/* --------------------------------------------------------------------- */
static int tmpfs_mount(struct mount *);
static int tmpfs_unmount(struct mount *, int);
static int tmpfs_root(struct mount *, int flags, struct vnode **);
static int tmpfs_fhtovp(struct mount *, struct fid *, struct vnode **);
static int tmpfs_statfs(struct mount *, struct statfs *);
/* --------------------------------------------------------------------- */
static const char *tmpfs_opts[] = {
"from", "size", "inodes", "uid", "gid", "mode", "export",
NULL
};
/* --------------------------------------------------------------------- */
#define SWI_MAXMIB 3
static u_int
get_swpgtotal(void)
{
struct xswdev xsd;
char *sname = "vm.swap_info";
int soid[SWI_MAXMIB], oid[2];
u_int unswdev, total, dmmax, nswapdev;
size_t mibi, len;
total = 0;
len = sizeof(dmmax);
if (kernel_sysctlbyname(curthread, "vm.dmmax", &dmmax, &len,
NULL, 0, NULL, 0) != 0)
return total;
len = sizeof(nswapdev);
if (kernel_sysctlbyname(curthread, "vm.nswapdev",
&nswapdev, &len,
NULL, 0, NULL, 0) != 0)
return total;
mibi = (SWI_MAXMIB - 1) * sizeof(int);
oid[0] = 0;
oid[1] = 3;
if (kernel_sysctl(curthread, oid, 2,
soid, &mibi, (void *)sname, strlen(sname),
NULL, 0) != 0)
return total;
mibi = (SWI_MAXMIB - 1);
for (unswdev = 0; unswdev < nswapdev; ++unswdev) {
soid[mibi] = unswdev;
len = sizeof(struct xswdev);
if (kernel_sysctl(curthread,
soid, mibi + 1, &xsd, &len, NULL, 0,
NULL, 0) != 0)
return total;
if (len == sizeof(struct xswdev))
total += (xsd.xsw_nblks - dmmax);
}
/* Not Reached */
return total;
}
/* --------------------------------------------------------------------- */
static int
tmpfs_node_ctor(void *mem, int size, void *arg, int flags)
{
struct tmpfs_node *node = (struct tmpfs_node *)mem;
node->tn_gen++;
node->tn_size = 0;
node->tn_status = 0;
node->tn_flags = 0;
node->tn_links = 0;
node->tn_vnode = NULL;
node->tn_vpstate = 0;
return (0);
}
static void
tmpfs_node_dtor(void *mem, int size, void *arg)
{
struct tmpfs_node *node = (struct tmpfs_node *)mem;
node->tn_type = VNON;
}
static int
tmpfs_node_init(void *mem, int size, int flags)
{
struct tmpfs_node *node = (struct tmpfs_node *)mem;
node->tn_id = 0;
mtx_init(&node->tn_interlock, "tmpfs node interlock", NULL, MTX_DEF);
node->tn_gen = arc4random();
return (0);
}
static void
tmpfs_node_fini(void *mem, int size)
{
struct tmpfs_node *node = (struct tmpfs_node *)mem;
mtx_destroy(&node->tn_interlock);
}
static int
tmpfs_mount(struct mount *mp)
{
struct tmpfs_mount *tmp;
struct tmpfs_node *root;
size_t pages, mem_size;
ino_t nodes;
int error;
/* Size counters. */
ino_t nodes_max;
size_t size_max;
/* Root node attributes. */
uid_t root_uid;
gid_t root_gid;
mode_t root_mode;
struct vattr va;
if (vfs_filteropt(mp->mnt_optnew, tmpfs_opts))
return (EINVAL);
if (mp->mnt_flag & MNT_UPDATE) {
/* XXX: There is no support yet to update file system
* settings. Should be added. */
return EOPNOTSUPP;
}
printf("WARNING: TMPFS is considered to be a highly experimental "
"feature in FreeBSD.\n");
vn_lock(mp->mnt_vnodecovered, LK_SHARED | LK_RETRY);
error = VOP_GETATTR(mp->mnt_vnodecovered, &va, mp->mnt_cred);
VOP_UNLOCK(mp->mnt_vnodecovered, 0);
if (error)
return (error);
if (mp->mnt_cred->cr_ruid != 0 ||
vfs_scanopt(mp->mnt_optnew, "gid", "%d", &root_gid) != 1)
root_gid = va.va_gid;
if (mp->mnt_cred->cr_ruid != 0 ||
vfs_scanopt(mp->mnt_optnew, "uid", "%d", &root_uid) != 1)
root_uid = va.va_uid;
if (mp->mnt_cred->cr_ruid != 0 ||
vfs_scanopt(mp->mnt_optnew, "mode", "%ho", &root_mode) != 1)
root_mode = va.va_mode;
if (vfs_scanopt(mp->mnt_optnew, "inodes", "%d", &nodes_max) != 1)
nodes_max = 0;
if (vfs_scanopt(mp->mnt_optnew, "size", "%qu", &size_max) != 1)
size_max = 0;
/* Do not allow mounts if we do not have enough memory to preserve
* the minimum reserved pages. */
mem_size = cnt.v_free_count + cnt.v_inactive_count + get_swpgtotal();
mem_size -= mem_size > cnt.v_wire_count ? cnt.v_wire_count : mem_size;
if (mem_size < TMPFS_PAGES_RESERVED)
return ENOSPC;
/* Get the maximum number of memory pages this file system is
* allowed to use, based on the maximum size the user passed in
* the mount structure. A value of zero is treated as if the
* maximum available space was requested. */
if (size_max < PAGE_SIZE || size_max >= SIZE_MAX)
pages = SIZE_MAX;
else
pages = howmany(size_max, PAGE_SIZE);
MPASS(pages > 0);
if (nodes_max <= 3)
nodes = 3 + pages * PAGE_SIZE / 1024;
else
nodes = nodes_max;
MPASS(nodes >= 3);
/* Allocate the tmpfs mount structure and fill it. */
tmp = (struct tmpfs_mount *)malloc(sizeof(struct tmpfs_mount),
M_TMPFSMNT, M_WAITOK | M_ZERO);
mtx_init(&tmp->allnode_lock, "tmpfs allnode lock", NULL, MTX_DEF);
tmp->tm_nodes_max = nodes;
tmp->tm_nodes_inuse = 0;
tmp->tm_maxfilesize = (u_int64_t)(cnt.v_page_count + get_swpgtotal()) * PAGE_SIZE;
LIST_INIT(&tmp->tm_nodes_used);
tmp->tm_pages_max = pages;
tmp->tm_pages_used = 0;
tmp->tm_ino_unr = new_unrhdr(2, INT_MAX, &tmp->allnode_lock);
tmp->tm_dirent_pool = uma_zcreate("TMPFS dirent",
sizeof(struct tmpfs_dirent),
NULL, NULL, NULL, NULL,
UMA_ALIGN_PTR, 0);
tmp->tm_node_pool = uma_zcreate("TMPFS node",
sizeof(struct tmpfs_node),
tmpfs_node_ctor, tmpfs_node_dtor,
tmpfs_node_init, tmpfs_node_fini,
UMA_ALIGN_PTR, 0);
/* Allocate the root node. */
error = tmpfs_alloc_node(tmp, VDIR, root_uid,
root_gid, root_mode & ALLPERMS, NULL, NULL,
VNOVAL, &root);
if (error != 0 || root == NULL) {
uma_zdestroy(tmp->tm_node_pool);
uma_zdestroy(tmp->tm_dirent_pool);
delete_unrhdr(tmp->tm_ino_unr);
free(tmp, M_TMPFSMNT);
return error;
}
KASSERT(root->tn_id == 2, ("tmpfs root with invalid ino: %d", root->tn_id));
tmp->tm_root = root;
MNT_ILOCK(mp);
mp->mnt_flag |= MNT_LOCAL;
mp->mnt_kern_flag |= MNTK_MPSAFE;
MNT_IUNLOCK(mp);
mp->mnt_data = tmp;
mp->mnt_stat.f_namemax = MAXNAMLEN;
vfs_getnewfsid(mp);
vfs_mountedfrom(mp, "tmpfs");
return 0;
}
/* --------------------------------------------------------------------- */
/* ARGSUSED2 */
static int
tmpfs_unmount(struct mount *mp, int mntflags)
{
int error;
int flags = 0;
struct tmpfs_mount *tmp;
struct tmpfs_node *node;
/* Handle forced unmounts. */
if (mntflags & MNT_FORCE)
flags |= FORCECLOSE;
/* Finalize all pending I/O. */
error = vflush(mp, 0, flags, curthread);
if (error != 0)
return error;
tmp = VFS_TO_TMPFS(mp);
/* Free all associated data. The loop iterates over the linked list
* we have containing all used nodes. For each of them that is
* a directory, we free all its directory entries. Note that after
* freeing a node, it will automatically go to the available list,
* so we will later have to iterate over it to release its items. */
node = LIST_FIRST(&tmp->tm_nodes_used);
while (node != NULL) {
struct tmpfs_node *next;
if (node->tn_type == VDIR) {
struct tmpfs_dirent *de;
de = TAILQ_FIRST(&node->tn_dir.tn_dirhead);
while (de != NULL) {
struct tmpfs_dirent *nde;
nde = TAILQ_NEXT(de, td_entries);
tmpfs_free_dirent(tmp, de, FALSE);
de = nde;
node->tn_size -= sizeof(struct tmpfs_dirent);
}
}
next = LIST_NEXT(node, tn_entries);
tmpfs_free_node(tmp, node);
node = next;
}
uma_zdestroy(tmp->tm_dirent_pool);
uma_zdestroy(tmp->tm_node_pool);
delete_unrhdr(tmp->tm_ino_unr);
mtx_destroy(&tmp->allnode_lock);
MPASS(tmp->tm_pages_used == 0);
MPASS(tmp->tm_nodes_inuse == 0);
/* Throw away the tmpfs_mount structure. */
free(mp->mnt_data, M_TMPFSMNT);
mp->mnt_data = NULL;
MNT_ILOCK(mp);
mp->mnt_flag &= ~MNT_LOCAL;
MNT_IUNLOCK(mp);
return 0;
}
/* --------------------------------------------------------------------- */
static int
tmpfs_root(struct mount *mp, int flags, struct vnode **vpp)
{
int error;
error = tmpfs_alloc_vp(mp, VFS_TO_TMPFS(mp)->tm_root, flags, vpp);
if (!error)
(*vpp)->v_vflag |= VV_ROOT;
return error;
}
/* --------------------------------------------------------------------- */
static int
tmpfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp)
{
boolean_t found;
struct tmpfs_fid *tfhp;
struct tmpfs_mount *tmp;
struct tmpfs_node *node;
tmp = VFS_TO_TMPFS(mp);
tfhp = (struct tmpfs_fid *)fhp;
if (tfhp->tf_len != sizeof(struct tmpfs_fid))
return EINVAL;
if (tfhp->tf_id >= tmp->tm_nodes_max)
return EINVAL;
found = FALSE;
TMPFS_LOCK(tmp);
LIST_FOREACH(node, &tmp->tm_nodes_used, tn_entries) {
if (node->tn_id == tfhp->tf_id &&
node->tn_gen == tfhp->tf_gen) {
found = TRUE;
break;
}
}
TMPFS_UNLOCK(tmp);
if (found)
return (tmpfs_alloc_vp(mp, node, LK_EXCLUSIVE, vpp));
return (EINVAL);
}
/* --------------------------------------------------------------------- */
/* ARGSUSED2 */
static int
tmpfs_statfs(struct mount *mp, struct statfs *sbp)
{
fsfilcnt_t freenodes;
struct tmpfs_mount *tmp;
tmp = VFS_TO_TMPFS(mp);
sbp->f_iosize = PAGE_SIZE;
sbp->f_bsize = PAGE_SIZE;
sbp->f_blocks = TMPFS_PAGES_MAX(tmp);
sbp->f_bavail = sbp->f_bfree = TMPFS_PAGES_AVAIL(tmp);
freenodes = MIN(tmp->tm_nodes_max - tmp->tm_nodes_inuse,
TMPFS_PAGES_AVAIL(tmp) * PAGE_SIZE / sizeof(struct tmpfs_node));
sbp->f_files = freenodes + tmp->tm_nodes_inuse;
sbp->f_ffree = freenodes;
/* sbp->f_owner = tmp->tn_uid; */
return 0;
}
/* --------------------------------------------------------------------- */
/*
* tmpfs vfs operations.
*/
struct vfsops tmpfs_vfsops = {
.vfs_mount = tmpfs_mount,
.vfs_unmount = tmpfs_unmount,
.vfs_root = tmpfs_root,
.vfs_statfs = tmpfs_statfs,
.vfs_fhtovp = tmpfs_fhtovp,
};
VFS_SET(tmpfs_vfsops, tmpfs, 0);