* 2000-2001 Christoph Rohland
* 2000-2001 SAP AG
* 2002 Red Hat Inc.
- * Copyright (C) 2002-2003 Hugh Dickins.
- * Copyright (C) 2002-2003 VERITAS Software Corporation.
+ * Copyright (C) 2002-2005 Hugh Dickins.
+ * Copyright (C) 2002-2005 VERITAS Software Corporation.
* Copyright (C) 2004 Andi Kleen, SuSE Labs
*
+ * Extended attribute support for tmpfs:
+ * Copyright (c) 2004, Luke Kenneth Casson Leighton <lkcl@lkcl.net>
+ * Copyright (c) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
+ *
* This file is released under the GPL.
*/
* which makes it a completely usable filesystem.
*/
-#include <linux/config.h>
#include <linux/module.h>
#include <linux/init.h>
-#include <linux/devfs_fs_kernel.h>
#include <linux/fs.h>
+#include <linux/xattr.h>
+#include <linux/generic_acl.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/file.h>
#include <linux/swapops.h>
#include <linux/mempolicy.h>
#include <linux/namei.h>
+#include <linux/ctype.h>
+#include <linux/migrate.h>
+#include <linux/highmem.h>
+#include <linux/backing-dev.h>
+
#include <asm/uaccess.h>
#include <asm/div64.h>
#include <asm/pgtable.h>
/* This magic number is used in glibc for posix shared memory */
-#define TMPFS_MAGIC 0x01021994
#define ENTRIES_PER_PAGE (PAGE_CACHE_SIZE/sizeof(unsigned long))
#define ENTRIES_PER_PAGEPAGE (ENTRIES_PER_PAGE*ENTRIES_PER_PAGE)
#define SHMEM_PAGEIN VM_READ
#define SHMEM_TRUNCATE VM_WRITE
+/* Definition to limit shmem_truncate's steps between cond_rescheds */
+#define LATENCY_LIMIT 64
+
/* Pretend that each entry is of this size in directory's i_size */
#define BOGO_DIRENT_SIZE 20
-/* Keep swapped page count in private field of indirect struct page */
-#define nr_swapped private
-
/* Flag allocation requirements to shmem_getpage and shmem_swp_alloc */
enum sgp_type {
SGP_QUICK, /* don't try more than file page cache lookup */
static int shmem_getpage(struct inode *inode, unsigned long idx,
struct page **pagep, enum sgp_type sgp, int *type);
-static inline struct page *shmem_dir_alloc(unsigned int gfp_mask)
+static inline struct page *shmem_dir_alloc(gfp_t gfp_mask)
{
/*
* The above definition of ENTRIES_PER_PAGE, and the use of
}
static struct super_operations shmem_ops;
-static struct address_space_operations shmem_aops;
-static struct file_operations shmem_file_operations;
+static const struct address_space_operations shmem_aops;
+static const struct file_operations shmem_file_operations;
static struct inode_operations shmem_inode_operations;
static struct inode_operations shmem_dir_inode_operations;
+static struct inode_operations shmem_special_inode_operations;
static struct vm_operations_struct shmem_vm_ops;
-static struct backing_dev_info shmem_backing_dev_info = {
+static struct backing_dev_info shmem_backing_dev_info __read_mostly = {
.ra_pages = 0, /* No readahead */
- .memory_backed = 1, /* Does not contribute to dirty memory */
- .unplug_io_fn = default_unplug_io_fn,
+ .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK,
+ .unplug_io_fn = default_unplug_io_fn,
};
-LIST_HEAD(shmem_inodes);
-static spinlock_t shmem_ilock = SPIN_LOCK_UNLOCKED;
+static LIST_HEAD(shmem_swaplist);
+static DEFINE_SPINLOCK(shmem_swaplist_lock);
-static void shmem_free_block(struct inode *inode)
+static void shmem_free_blocks(struct inode *inode, long pages)
{
struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
- spin_lock(&sbinfo->stat_lock);
- sbinfo->free_blocks++;
- inode->i_blocks -= BLOCKS_PER_PAGE;
- spin_unlock(&sbinfo->stat_lock);
+ if (sbinfo->max_blocks) {
+ spin_lock(&sbinfo->stat_lock);
+ sbinfo->free_blocks += pages;
+ inode->i_blocks -= pages*BLOCKS_PER_PAGE;
+ spin_unlock(&sbinfo->stat_lock);
+ }
}
/*
freed = info->alloced - info->swapped - inode->i_mapping->nrpages;
if (freed > 0) {
- struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
info->alloced -= freed;
- spin_lock(&sbinfo->stat_lock);
- sbinfo->free_blocks += freed;
- inode->i_blocks -= freed*BLOCKS_PER_PAGE;
- spin_unlock(&sbinfo->stat_lock);
shmem_unacct_blocks(info->flags, freed);
+ shmem_free_blocks(inode, freed);
}
}
entry->val = value;
info->swapped += incdec;
- if ((unsigned long)(entry - info->i_direct) >= SHMEM_NR_DIRECT)
- kmap_atomic_to_page(entry)->nr_swapped += incdec;
+ if ((unsigned long)(entry - info->i_direct) >= SHMEM_NR_DIRECT) {
+ struct page *page = kmap_atomic_to_page(entry);
+ set_page_private(page, page_private(page) + incdec);
+ }
}
/*
struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
struct page *page = NULL;
swp_entry_t *entry;
- static const swp_entry_t unswapped = { 0 };
if (sgp != SGP_WRITE &&
((loff_t) index << PAGE_CACHE_SHIFT) >= i_size_read(inode))
while (!(entry = shmem_swp_entry(info, index, &page))) {
if (sgp == SGP_READ)
- return (swp_entry_t *) &unswapped;
+ return shmem_swp_map(ZERO_PAGE(0));
/*
* Test free_blocks against 1 not 0, since we have 1 data
* page (and perhaps indirect index pages) yet to allocate:
* a waste to allocate index if we cannot allocate data.
*/
- spin_lock(&sbinfo->stat_lock);
- if (sbinfo->free_blocks <= 1) {
+ if (sbinfo->max_blocks) {
+ spin_lock(&sbinfo->stat_lock);
+ if (sbinfo->free_blocks <= 1) {
+ spin_unlock(&sbinfo->stat_lock);
+ return ERR_PTR(-ENOSPC);
+ }
+ sbinfo->free_blocks--;
+ inode->i_blocks += BLOCKS_PER_PAGE;
spin_unlock(&sbinfo->stat_lock);
- return ERR_PTR(-ENOSPC);
}
- sbinfo->free_blocks--;
- inode->i_blocks += BLOCKS_PER_PAGE;
- spin_unlock(&sbinfo->stat_lock);
spin_unlock(&info->lock);
- page = shmem_dir_alloc(mapping_gfp_mask(inode->i_mapping));
- if (page) {
- clear_highpage(page);
- page->nr_swapped = 0;
- }
+ page = shmem_dir_alloc(mapping_gfp_mask(inode->i_mapping) | __GFP_ZERO);
+ if (page)
+ set_page_private(page, 0);
spin_lock(&info->lock);
if (!page) {
- shmem_free_block(inode);
+ shmem_free_blocks(inode, 1);
return ERR_PTR(-ENOMEM);
}
if (sgp != SGP_WRITE &&
}
if (page) {
/* another task gave its page, or truncated the file */
- shmem_free_block(inode);
+ shmem_free_blocks(inode, 1);
shmem_dir_free(page);
}
if (info->next_index <= index && !IS_ERR(entry))
/*
* shmem_free_swp - free some swap entries in a directory
*
- * @dir: pointer to the directory
- * @edir: pointer after last entry of the directory
+ * @dir: pointer to the directory
+ * @edir: pointer after last entry of the directory
+ * @punch_lock: pointer to spinlock when needed for the holepunch case
*/
-static int shmem_free_swp(swp_entry_t *dir, swp_entry_t *edir)
+static int shmem_free_swp(swp_entry_t *dir, swp_entry_t *edir,
+ spinlock_t *punch_lock)
{
+ spinlock_t *punch_unlock = NULL;
swp_entry_t *ptr;
int freed = 0;
for (ptr = dir; ptr < edir; ptr++) {
if (ptr->val) {
+ if (unlikely(punch_lock)) {
+ punch_unlock = punch_lock;
+ punch_lock = NULL;
+ spin_lock(punch_unlock);
+ if (!ptr->val)
+ continue;
+ }
free_swap_and_cache(*ptr);
*ptr = (swp_entry_t){0};
freed++;
}
}
+ if (punch_unlock)
+ spin_unlock(punch_unlock);
return freed;
}
-static void shmem_truncate(struct inode *inode)
+static int shmem_map_and_free_swp(struct page *subdir, int offset,
+ int limit, struct page ***dir, spinlock_t *punch_lock)
+{
+ swp_entry_t *ptr;
+ int freed = 0;
+
+ ptr = shmem_swp_map(subdir);
+ for (; offset < limit; offset += LATENCY_LIMIT) {
+ int size = limit - offset;
+ if (size > LATENCY_LIMIT)
+ size = LATENCY_LIMIT;
+ freed += shmem_free_swp(ptr+offset, ptr+offset+size,
+ punch_lock);
+ if (need_resched()) {
+ shmem_swp_unmap(ptr);
+ if (*dir) {
+ shmem_dir_unmap(*dir);
+ *dir = NULL;
+ }
+ cond_resched();
+ ptr = shmem_swp_map(subdir);
+ }
+ }
+ shmem_swp_unmap(ptr);
+ return freed;
+}
+
+static void shmem_free_pages(struct list_head *next)
+{
+ struct page *page;
+ int freed = 0;
+
+ do {
+ page = container_of(next, struct page, lru);
+ next = next->next;
+ shmem_dir_free(page);
+ freed++;
+ if (freed >= LATENCY_LIMIT) {
+ cond_resched();
+ freed = 0;
+ }
+ } while (next);
+}
+
+static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end)
{
struct shmem_inode_info *info = SHMEM_I(inode);
unsigned long idx;
unsigned long size;
unsigned long limit;
unsigned long stage;
+ unsigned long diroff;
struct page **dir;
+ struct page *topdir;
+ struct page *middir;
struct page *subdir;
- struct page *empty;
swp_entry_t *ptr;
+ LIST_HEAD(pages_to_free);
+ long nr_pages_to_free = 0;
+ long nr_swaps_freed = 0;
int offset;
int freed;
+ int punch_hole;
+ spinlock_t *needs_lock;
+ spinlock_t *punch_lock;
+ unsigned long upper_limit;
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
- idx = (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+ idx = (start + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
if (idx >= info->next_index)
return;
spin_lock(&info->lock);
info->flags |= SHMEM_TRUNCATE;
- limit = info->next_index;
- info->next_index = idx;
+ if (likely(end == (loff_t) -1)) {
+ limit = info->next_index;
+ upper_limit = SHMEM_MAX_INDEX;
+ info->next_index = idx;
+ needs_lock = NULL;
+ punch_hole = 0;
+ } else {
+ if (end + 1 >= inode->i_size) { /* we may free a little more */
+ limit = (inode->i_size + PAGE_CACHE_SIZE - 1) >>
+ PAGE_CACHE_SHIFT;
+ upper_limit = SHMEM_MAX_INDEX;
+ } else {
+ limit = (end + 1) >> PAGE_CACHE_SHIFT;
+ upper_limit = limit;
+ }
+ needs_lock = &info->lock;
+ punch_hole = 1;
+ }
+
+ topdir = info->i_indirect;
+ if (topdir && idx <= SHMEM_NR_DIRECT && !punch_hole) {
+ info->i_indirect = NULL;
+ nr_pages_to_free++;
+ list_add(&topdir->lru, &pages_to_free);
+ }
+ spin_unlock(&info->lock);
+
if (info->swapped && idx < SHMEM_NR_DIRECT) {
ptr = info->i_direct;
size = limit;
if (size > SHMEM_NR_DIRECT)
size = SHMEM_NR_DIRECT;
- info->swapped -= shmem_free_swp(ptr+idx, ptr+size);
+ nr_swaps_freed = shmem_free_swp(ptr+idx, ptr+size, needs_lock);
}
- if (!info->i_indirect)
+
+ /*
+ * If there are no indirect blocks or we are punching a hole
+ * below indirect blocks, nothing to be done.
+ */
+ if (!topdir || limit <= SHMEM_NR_DIRECT)
goto done2;
- BUG_ON(limit <= SHMEM_NR_DIRECT);
+ /*
+ * The truncation case has already dropped info->lock, and we're safe
+ * because i_size and next_index have already been lowered, preventing
+ * access beyond. But in the punch_hole case, we still need to take
+ * the lock when updating the swap directory, because there might be
+ * racing accesses by shmem_getpage(SGP_CACHE), shmem_unuse_inode or
+ * shmem_writepage. However, whenever we find we can remove a whole
+ * directory page (not at the misaligned start or end of the range),
+ * we first NULLify its pointer in the level above, and then have no
+ * need to take the lock when updating its contents: needs_lock and
+ * punch_lock (either pointing to info->lock or NULL) manage this.
+ */
+
+ upper_limit -= SHMEM_NR_DIRECT;
limit -= SHMEM_NR_DIRECT;
idx = (idx > SHMEM_NR_DIRECT)? (idx - SHMEM_NR_DIRECT): 0;
offset = idx % ENTRIES_PER_PAGE;
idx -= offset;
- empty = NULL;
- dir = shmem_dir_map(info->i_indirect);
+ dir = shmem_dir_map(topdir);
stage = ENTRIES_PER_PAGEPAGE/2;
- if (idx < ENTRIES_PER_PAGEPAGE/2)
- dir += idx/ENTRIES_PER_PAGE;
- else {
+ if (idx < ENTRIES_PER_PAGEPAGE/2) {
+ middir = topdir;
+ diroff = idx/ENTRIES_PER_PAGE;
+ } else {
dir += ENTRIES_PER_PAGE/2;
dir += (idx - ENTRIES_PER_PAGEPAGE/2)/ENTRIES_PER_PAGEPAGE;
while (stage <= idx)
stage += ENTRIES_PER_PAGEPAGE;
+ middir = *dir;
if (*dir) {
- subdir = *dir;
- size = ((idx - ENTRIES_PER_PAGEPAGE/2) %
+ diroff = ((idx - ENTRIES_PER_PAGEPAGE/2) %
ENTRIES_PER_PAGEPAGE) / ENTRIES_PER_PAGE;
- if (!size && !offset) {
- empty = subdir;
- *dir = NULL;
+ if (!diroff && !offset && upper_limit >= stage) {
+ if (needs_lock) {
+ spin_lock(needs_lock);
+ *dir = NULL;
+ spin_unlock(needs_lock);
+ needs_lock = NULL;
+ } else
+ *dir = NULL;
+ nr_pages_to_free++;
+ list_add(&middir->lru, &pages_to_free);
}
shmem_dir_unmap(dir);
- dir = shmem_dir_map(subdir) + size;
+ dir = shmem_dir_map(middir);
} else {
+ diroff = 0;
offset = 0;
idx = stage;
}
}
- for (; idx < limit; idx += ENTRIES_PER_PAGE, dir++) {
+ for (; idx < limit; idx += ENTRIES_PER_PAGE, diroff++) {
if (unlikely(idx == stage)) {
- shmem_dir_unmap(dir-1);
- dir = shmem_dir_map(info->i_indirect) +
+ shmem_dir_unmap(dir);
+ dir = shmem_dir_map(topdir) +
ENTRIES_PER_PAGE/2 + idx/ENTRIES_PER_PAGEPAGE;
while (!*dir) {
dir++;
goto done1;
}
stage = idx + ENTRIES_PER_PAGEPAGE;
- subdir = *dir;
- *dir = NULL;
- shmem_dir_unmap(dir);
- if (empty) {
- shmem_dir_free(empty);
- shmem_free_block(inode);
+ middir = *dir;
+ if (punch_hole)
+ needs_lock = &info->lock;
+ if (upper_limit >= stage) {
+ if (needs_lock) {
+ spin_lock(needs_lock);
+ *dir = NULL;
+ spin_unlock(needs_lock);
+ needs_lock = NULL;
+ } else
+ *dir = NULL;
+ nr_pages_to_free++;
+ list_add(&middir->lru, &pages_to_free);
}
- empty = subdir;
- cond_resched_lock(&info->lock);
- dir = shmem_dir_map(subdir);
+ shmem_dir_unmap(dir);
+ cond_resched();
+ dir = shmem_dir_map(middir);
+ diroff = 0;
}
- subdir = *dir;
- if (subdir && subdir->nr_swapped) {
- ptr = shmem_swp_map(subdir);
+ punch_lock = needs_lock;
+ subdir = dir[diroff];
+ if (subdir && !offset && upper_limit-idx >= ENTRIES_PER_PAGE) {
+ if (needs_lock) {
+ spin_lock(needs_lock);
+ dir[diroff] = NULL;
+ spin_unlock(needs_lock);
+ punch_lock = NULL;
+ } else
+ dir[diroff] = NULL;
+ nr_pages_to_free++;
+ list_add(&subdir->lru, &pages_to_free);
+ }
+ if (subdir && page_private(subdir) /* has swap entries */) {
size = limit - idx;
if (size > ENTRIES_PER_PAGE)
size = ENTRIES_PER_PAGE;
- freed = shmem_free_swp(ptr+offset, ptr+size);
- shmem_swp_unmap(ptr);
- info->swapped -= freed;
- subdir->nr_swapped -= freed;
- BUG_ON(subdir->nr_swapped > offset);
- }
- if (offset)
- offset = 0;
- else if (subdir) {
- *dir = NULL;
- shmem_dir_free(subdir);
- shmem_free_block(inode);
+ freed = shmem_map_and_free_swp(subdir,
+ offset, size, &dir, punch_lock);
+ if (!dir)
+ dir = shmem_dir_map(middir);
+ nr_swaps_freed += freed;
+ if (offset || punch_lock) {
+ spin_lock(&info->lock);
+ set_page_private(subdir,
+ page_private(subdir) - freed);
+ spin_unlock(&info->lock);
+ } else
+ BUG_ON(page_private(subdir) != freed);
}
+ offset = 0;
}
done1:
- shmem_dir_unmap(dir-1);
- if (empty) {
- shmem_dir_free(empty);
- shmem_free_block(inode);
- }
- if (info->next_index <= SHMEM_NR_DIRECT) {
- shmem_dir_free(info->i_indirect);
- info->i_indirect = NULL;
- shmem_free_block(inode);
- }
+ shmem_dir_unmap(dir);
done2:
- BUG_ON(info->swapped > info->next_index);
if (inode->i_mapping->nrpages && (info->flags & SHMEM_PAGEIN)) {
/*
* Call truncate_inode_pages again: racing shmem_unuse_inode
* generic_delete_inode did it, before we lowered next_index.
* Also, though shmem_getpage checks i_size before adding to
* cache, no recheck after: so fix the narrow window there too.
+ *
+ * Recalling truncate_inode_pages_range and unmap_mapping_range
+ * every time for punch_hole (which never got a chance to clear
+ * SHMEM_PAGEIN at the start of vmtruncate_range) is expensive,
+ * yet hardly ever necessary: try to optimize them out later.
*/
- spin_unlock(&info->lock);
- truncate_inode_pages(inode->i_mapping, inode->i_size);
- spin_lock(&info->lock);
+ truncate_inode_pages_range(inode->i_mapping, start, end);
+ if (punch_hole)
+ unmap_mapping_range(inode->i_mapping, start,
+ end - start, 1);
}
+
+ spin_lock(&info->lock);
info->flags &= ~SHMEM_TRUNCATE;
+ info->swapped -= nr_swaps_freed;
+ if (nr_pages_to_free)
+ shmem_free_blocks(inode, nr_pages_to_free);
shmem_recalc_inode(inode);
spin_unlock(&info->lock);
+
+ /*
+ * Empty swap vector directory pages to be freed?
+ */
+ if (!list_empty(&pages_to_free)) {
+ pages_to_free.prev->next = NULL;
+ shmem_free_pages(pages_to_free.next);
+ }
+}
+
+static void shmem_truncate(struct inode *inode)
+{
+ shmem_truncate_range(inode, inode->i_size, (loff_t)-1);
}
static int shmem_notify_change(struct dentry *dentry, struct iattr *attr)
struct page *page = NULL;
int error;
- if (attr->ia_valid & ATTR_SIZE) {
+ if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
if (attr->ia_size < inode->i_size) {
/*
* If truncating down to a partial page, then
error = inode_change_ok(inode, attr);
if (!error)
error = inode_setattr(inode, attr);
+#ifdef CONFIG_TMPFS_POSIX_ACL
+ if (!error && (attr->ia_valid & ATTR_MODE))
+ error = generic_acl_chmod(inode, &shmem_acl_ops);
+#endif
if (page)
page_cache_release(page);
return error;
struct shmem_inode_info *info = SHMEM_I(inode);
if (inode->i_op->truncate == shmem_truncate) {
- spin_lock(&shmem_ilock);
- list_del(&info->list);
- spin_unlock(&shmem_ilock);
+ truncate_inode_pages(inode->i_mapping, 0);
shmem_unacct_size(info->flags, inode->i_size);
inode->i_size = 0;
shmem_truncate(inode);
+ if (!list_empty(&info->swaplist)) {
+ spin_lock(&shmem_swaplist_lock);
+ list_del_init(&info->swaplist);
+ spin_unlock(&shmem_swaplist_lock);
+ }
}
BUG_ON(inode->i_blocks);
- spin_lock(&sbinfo->stat_lock);
- sbinfo->free_inodes++;
- spin_unlock(&sbinfo->stat_lock);
+ if (sbinfo->max_inodes) {
+ spin_lock(&sbinfo->stat_lock);
+ sbinfo->free_inodes++;
+ spin_unlock(&sbinfo->stat_lock);
+ }
clear_inode(inode);
}
}
if (!info->i_indirect)
goto lost2;
- /* we might be racing with shmem_truncate */
- if (limit <= SHMEM_NR_DIRECT)
- goto lost2;
dir = shmem_dir_map(info->i_indirect);
stage = SHMEM_NR_DIRECT + ENTRIES_PER_PAGEPAGE/2;
dir = shmem_dir_map(subdir);
}
subdir = *dir;
- if (subdir && subdir->nr_swapped) {
+ if (subdir && page_private(subdir)) {
ptr = shmem_swp_map(subdir);
size = limit - idx;
if (size > ENTRIES_PER_PAGE)
*/
int shmem_unuse(swp_entry_t entry, struct page *page)
{
- struct list_head *p;
+ struct list_head *p, *next;
struct shmem_inode_info *info;
int found = 0;
- spin_lock(&shmem_ilock);
- list_for_each(p, &shmem_inodes) {
- info = list_entry(p, struct shmem_inode_info, list);
-
- if (info->swapped && shmem_unuse_inode(info, entry, page)) {
+ spin_lock(&shmem_swaplist_lock);
+ list_for_each_safe(p, next, &shmem_swaplist) {
+ info = list_entry(p, struct shmem_inode_info, swaplist);
+ if (!info->swapped)
+ list_del_init(&info->swaplist);
+ else if (shmem_unuse_inode(info, entry, page)) {
/* move head to start search for next from here */
- list_move_tail(&shmem_inodes, &info->list);
+ list_move_tail(&shmem_swaplist, &info->swaplist);
found = 1;
break;
}
}
- spin_unlock(&shmem_ilock);
+ spin_unlock(&shmem_swaplist_lock);
return found;
}
shmem_swp_set(info, entry, swap.val);
shmem_swp_unmap(entry);
spin_unlock(&info->lock);
+ if (list_empty(&info->swaplist)) {
+ spin_lock(&shmem_swaplist_lock);
+ /* move instead of add in case we're racing */
+ list_move_tail(&info->swaplist, &shmem_swaplist);
+ spin_unlock(&shmem_swaplist_lock);
+ }
unlock_page(page);
return 0;
}
swap_free(swap);
redirty:
set_page_dirty(page);
- return WRITEPAGE_ACTIVATE; /* Return with the page locked */
+ return AOP_WRITEPAGE_ACTIVATE; /* Return with the page locked */
}
#ifdef CONFIG_NUMA
+static inline int shmem_parse_mpol(char *value, int *policy, nodemask_t *policy_nodes)
+{
+ char *nodelist = strchr(value, ':');
+ int err = 1;
+
+ if (nodelist) {
+ /* NUL-terminate policy string */
+ *nodelist++ = '\0';
+ if (nodelist_parse(nodelist, *policy_nodes))
+ goto out;
+ }
+ if (!strcmp(value, "default")) {
+ *policy = MPOL_DEFAULT;
+ /* Don't allow a nodelist */
+ if (!nodelist)
+ err = 0;
+ } else if (!strcmp(value, "prefer")) {
+ *policy = MPOL_PREFERRED;
+ /* Insist on a nodelist of one node only */
+ if (nodelist) {
+ char *rest = nodelist;
+ while (isdigit(*rest))
+ rest++;
+ if (!*rest)
+ err = 0;
+ }
+ } else if (!strcmp(value, "bind")) {
+ *policy = MPOL_BIND;
+ /* Insist on a nodelist */
+ if (nodelist)
+ err = 0;
+ } else if (!strcmp(value, "interleave")) {
+ *policy = MPOL_INTERLEAVE;
+ /* Default to nodes online if no nodelist */
+ if (!nodelist)
+ *policy_nodes = node_online_map;
+ err = 0;
+ }
+out:
+ /* Restore string for error message */
+ if (nodelist)
+ *--nodelist = ':';
+ return err;
+}
+
static struct page *shmem_swapin_async(struct shared_policy *p,
swp_entry_t entry, unsigned long idx)
{
}
static struct page *
-shmem_alloc_page(unsigned long gfp, struct shmem_inode_info *info,
+shmem_alloc_page(gfp_t gfp, struct shmem_inode_info *info,
unsigned long idx)
{
struct vm_area_struct pvma;
pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, idx);
pvma.vm_pgoff = idx;
pvma.vm_end = PAGE_SIZE;
- page = alloc_page_vma(gfp, &pvma, 0);
+ page = alloc_page_vma(gfp | __GFP_ZERO, &pvma, 0);
mpol_free(pvma.vm_policy);
return page;
}
#else
+static inline int shmem_parse_mpol(char *value, int *policy, nodemask_t *policy_nodes)
+{
+ return 1;
+}
+
static inline struct page *
shmem_swapin(struct shmem_inode_info *info,swp_entry_t entry,unsigned long idx)
{
}
static inline struct page *
-shmem_alloc_page(unsigned long gfp,struct shmem_inode_info *info,
- unsigned long idx)
+shmem_alloc_page(gfp_t gfp,struct shmem_inode_info *info, unsigned long idx)
{
- return alloc_page(gfp);
+ return alloc_page(gfp | __GFP_ZERO);
}
#endif
struct page *swappage;
swp_entry_t *entry;
swp_entry_t swap;
- int error, majmin = VM_FAULT_MINOR;
+ int error;
if (idx >= SHMEM_MAX_INDEX)
return -EFBIG;
swappage = lookup_swap_cache(swap);
if (!swappage) {
shmem_swp_unmap(entry);
- spin_unlock(&info->lock);
/* here we actually do the io */
- if (majmin == VM_FAULT_MINOR && type)
- inc_page_state(pgmajfault);
- majmin = VM_FAULT_MAJOR;
+ if (type && *type == VM_FAULT_MINOR) {
+ __count_vm_event(PGMAJFAULT);
+ *type = VM_FAULT_MAJOR;
+ }
+ spin_unlock(&info->lock);
swappage = shmem_swapin(info, swap, idx);
if (!swappage) {
spin_lock(&info->lock);
page_cache_release(swappage);
if (error == -ENOMEM) {
/* let kswapd refresh zone for GFP_ATOMICs */
- blk_congestion_wait(WRITE, HZ/50);
+ congestion_wait(WRITE, HZ/50);
}
goto repeat;
}
} else {
shmem_swp_unmap(entry);
sbinfo = SHMEM_SB(inode->i_sb);
- spin_lock(&sbinfo->stat_lock);
- if (sbinfo->free_blocks == 0 || shmem_acct_block(info->flags)) {
+ if (sbinfo->max_blocks) {
+ spin_lock(&sbinfo->stat_lock);
+ if (sbinfo->free_blocks == 0 ||
+ shmem_acct_block(info->flags)) {
+ spin_unlock(&sbinfo->stat_lock);
+ spin_unlock(&info->lock);
+ error = -ENOSPC;
+ goto failed;
+ }
+ sbinfo->free_blocks--;
+ inode->i_blocks += BLOCKS_PER_PAGE;
spin_unlock(&sbinfo->stat_lock);
+ } else if (shmem_acct_block(info->flags)) {
spin_unlock(&info->lock);
error = -ENOSPC;
goto failed;
}
- sbinfo->free_blocks--;
- inode->i_blocks += BLOCKS_PER_PAGE;
- spin_unlock(&sbinfo->stat_lock);
if (!filepage) {
spin_unlock(&info->lock);
idx);
if (!filepage) {
shmem_unacct_blocks(info->flags, 1);
- shmem_free_block(inode);
+ shmem_free_blocks(inode, 1);
error = -ENOMEM;
goto failed;
}
spin_unlock(&info->lock);
page_cache_release(filepage);
shmem_unacct_blocks(info->flags, 1);
- shmem_free_block(inode);
+ shmem_free_blocks(inode, 1);
filepage = NULL;
if (error)
goto failed;
info->alloced++;
spin_unlock(&info->lock);
- clear_highpage(filepage);
flush_dcache_page(filepage);
SetPageUptodate(filepage);
}
done:
- if (!*pagep) {
- if (filepage) {
- unlock_page(filepage);
- *pagep = filepage;
- } else
- *pagep = ZERO_PAGE(0);
+ if (*pagep != filepage) {
+ unlock_page(filepage);
+ *pagep = filepage;
}
- if (type)
- *type = majmin;
return 0;
failed:
struct page *shmem_nopage(struct vm_area_struct *vma, unsigned long address, int *type)
{
- struct inode *inode = vma->vm_file->f_dentry->d_inode;
+ struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
struct page *page = NULL;
unsigned long idx;
int error;
idx = (address - vma->vm_start) >> PAGE_SHIFT;
idx += vma->vm_pgoff;
idx >>= PAGE_CACHE_SHIFT - PAGE_SHIFT;
+ if (((loff_t) idx << PAGE_CACHE_SHIFT) >= i_size_read(inode))
+ return NOPAGE_SIGBUS;
error = shmem_getpage(inode, idx, &page, SGP_CACHE, type);
if (error)
unsigned long addr, unsigned long len,
pgprot_t prot, unsigned long pgoff, int nonblock)
{
- struct inode *inode = vma->vm_file->f_dentry->d_inode;
+ struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
struct mm_struct *mm = vma->vm_mm;
enum sgp_type sgp = nonblock? SGP_QUICK: SGP_CACHE;
unsigned long size;
err = shmem_getpage(inode, pgoff, &page, sgp, NULL);
if (err)
return err;
+ /* Page may still be null, but only if nonblock was set. */
if (page) {
mark_page_accessed(page);
err = install_page(mm, vma, addr, page, prot);
page_cache_release(page);
return err;
}
- } else if (nonblock) {
- /*
- * If a nonlinear mapping then store the file page
- * offset in the pte.
- */
- if (pgoff != linear_page_index(vma, addr)) {
- err = install_file_pte(mm, vma, addr, pgoff, prot);
- if (err)
- return err;
- }
+ } else if (vma->vm_flags & VM_NONLINEAR) {
+ /* No page was found just because we can't read it in
+ * now (being here implies nonblock != 0), but the page
+ * may exist, so set the PTE to fault it in later. */
+ err = install_file_pte(mm, vma, addr, pgoff, prot);
+ if (err)
+ return err;
}
len -= PAGE_SIZE;
#ifdef CONFIG_NUMA
int shmem_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
{
- struct inode *i = vma->vm_file->f_dentry->d_inode;
+ struct inode *i = vma->vm_file->f_path.dentry->d_inode;
return mpol_set_shared_policy(&SHMEM_I(i)->policy, vma, new);
}
struct mempolicy *
shmem_get_policy(struct vm_area_struct *vma, unsigned long addr)
{
- struct inode *i = vma->vm_file->f_dentry->d_inode;
+ struct inode *i = vma->vm_file->f_path.dentry->d_inode;
unsigned long idx;
idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
}
#endif
-/* Protects current->user->locked_shm from concurrent access */
-static spinlock_t shmem_lock_user = SPIN_LOCK_UNLOCKED;
-
-int shmem_lock(struct file *file, int lock, struct user_struct * user)
+int shmem_lock(struct file *file, int lock, struct user_struct *user)
{
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
struct shmem_inode_info *info = SHMEM_I(inode);
- unsigned long lock_limit, locked;
int retval = -ENOMEM;
spin_lock(&info->lock);
- spin_lock(&shmem_lock_user);
if (lock && !(info->flags & VM_LOCKED)) {
- locked = inode->i_size >> PAGE_SHIFT;
- locked += user->locked_shm;
- lock_limit = current->rlim[RLIMIT_MEMLOCK].rlim_cur;
- lock_limit >>= PAGE_SHIFT;
- if ((locked > lock_limit) && !capable(CAP_IPC_LOCK))
+ if (!user_shm_lock(inode->i_size, user))
goto out_nomem;
- /* for this branch user == current->user so it won't go away under us */
- atomic_inc(&user->__count);
- user->locked_shm = locked;
+ info->flags |= VM_LOCKED;
}
if (!lock && (info->flags & VM_LOCKED) && user) {
- locked = inode->i_size >> PAGE_SHIFT;
- user->locked_shm -= locked;
- free_uid(user);
- }
- if (lock)
- info->flags |= VM_LOCKED;
- else
+ user_shm_unlock(inode->i_size, user);
info->flags &= ~VM_LOCKED;
+ }
retval = 0;
out_nomem:
- spin_unlock(&shmem_lock_user);
spin_unlock(&info->lock);
return retval;
}
-static int shmem_mmap(struct file *file, struct vm_area_struct *vma)
+int shmem_mmap(struct file *file, struct vm_area_struct *vma)
{
file_accessed(file);
vma->vm_ops = &shmem_vm_ops;
struct shmem_inode_info *info;
struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
- spin_lock(&sbinfo->stat_lock);
- if (!sbinfo->free_inodes) {
+ if (sbinfo->max_inodes) {
+ spin_lock(&sbinfo->stat_lock);
+ if (!sbinfo->free_inodes) {
+ spin_unlock(&sbinfo->stat_lock);
+ return NULL;
+ }
+ sbinfo->free_inodes--;
spin_unlock(&sbinfo->stat_lock);
- return NULL;
}
- sbinfo->free_inodes--;
- spin_unlock(&sbinfo->stat_lock);
inode = new_inode(sb);
if (inode) {
inode->i_mode = mode;
inode->i_uid = current->fsuid;
inode->i_gid = current->fsgid;
- inode->i_blksize = PAGE_CACHE_SIZE;
inode->i_blocks = 0;
inode->i_mapping->a_ops = &shmem_aops;
inode->i_mapping->backing_dev_info = &shmem_backing_dev_info;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ inode->i_generation = get_seconds();
info = SHMEM_I(inode);
memset(info, 0, (char *)inode - (char *)info);
spin_lock_init(&info->lock);
- mpol_shared_policy_init(&info->policy);
+ INIT_LIST_HEAD(&info->swaplist);
+
switch (mode & S_IFMT) {
default:
+ inode->i_op = &shmem_special_inode_operations;
init_special_inode(inode, mode, dev);
break;
case S_IFREG:
inode->i_op = &shmem_inode_operations;
inode->i_fop = &shmem_file_operations;
- spin_lock(&shmem_ilock);
- list_add_tail(&info->list, &shmem_inodes);
- spin_unlock(&shmem_ilock);
+ mpol_shared_policy_init(&info->policy, sbinfo->policy,
+ &sbinfo->policy_nodes);
break;
case S_IFDIR:
- inode->i_nlink++;
+ inc_nlink(inode);
/* Some things misbehave if size == 0 on a directory */
inode->i_size = 2 * BOGO_DIRENT_SIZE;
inode->i_op = &shmem_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
break;
case S_IFLNK:
+ /*
+ * Must not load anything in the rbtree,
+ * mpol_free_shared_policy will not be called.
+ */
+ mpol_shared_policy_init(&info->policy, MPOL_DEFAULT,
+ NULL);
break;
}
+ } else if (sbinfo->max_inodes) {
+ spin_lock(&sbinfo->stat_lock);
+ sbinfo->free_inodes++;
+ spin_unlock(&sbinfo->stat_lock);
}
return inode;
}
-static int shmem_set_size(struct shmem_sb_info *info,
- unsigned long max_blocks, unsigned long max_inodes)
-{
- int error;
- unsigned long blocks, inodes;
-
- spin_lock(&info->stat_lock);
- blocks = info->max_blocks - info->free_blocks;
- inodes = info->max_inodes - info->free_inodes;
- error = -EINVAL;
- if (max_blocks < blocks)
- goto out;
- if (max_inodes < inodes)
- goto out;
- error = 0;
- info->max_blocks = max_blocks;
- info->free_blocks = max_blocks - blocks;
- info->max_inodes = max_inodes;
- info->free_inodes = max_inodes - inodes;
-out:
- spin_unlock(&info->stat_lock);
- return error;
-}
-
#ifdef CONFIG_TMPFS
-
static struct inode_operations shmem_symlink_inode_operations;
static struct inode_operations shmem_symlink_inline_operations;
static ssize_t
shmem_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
loff_t pos;
unsigned long written;
- int err;
+ ssize_t err;
if ((ssize_t) count < 0)
return -EINVAL;
if (!access_ok(VERIFY_READ, buf, count))
return -EFAULT;
- down(&inode->i_sem);
+ mutex_lock(&inode->i_mutex);
pos = *ppos;
written = 0;
if (err || !count)
goto out;
- err = remove_suid(file->f_dentry);
+ err = remove_suid(file->f_path.dentry);
if (err)
goto out;
__get_user(dummy, buf + bytes - 1);
kaddr = kmap_atomic(page, KM_USER0);
- left = __copy_from_user(kaddr + offset, buf, bytes);
+ left = __copy_from_user_inatomic(kaddr + offset,
+ buf, bytes);
kunmap_atomic(kaddr, KM_USER0);
}
if (left) {
if (written)
err = written;
out:
- up(&inode->i_sem);
+ mutex_unlock(&inode->i_mutex);
return err;
}
static void do_shmem_file_read(struct file *filp, loff_t *ppos, read_descriptor_t *desc, read_actor_t actor)
{
- struct inode *inode = filp->f_dentry->d_inode;
+ struct inode *inode = filp->f_path.dentry->d_inode;
struct address_space *mapping = inode->i_mapping;
unsigned long index, offset;
/*
* We must evaluate after, since reads (unlike writes)
- * are called without i_sem protection against truncate
+ * are called without i_mutex protection against truncate
*/
nr = PAGE_CACHE_SIZE;
i_size = i_size_read(inode);
if (index == end_index) {
nr = i_size & ~PAGE_CACHE_MASK;
if (nr <= offset) {
- page_cache_release(page);
+ if (page)
+ page_cache_release(page);
break;
}
}
nr -= offset;
- if (page != ZERO_PAGE(0)) {
+ if (page) {
/*
* If users can be writing to this page using arbitrary
* virtual addresses, take care about potential aliasing
*/
if (!offset)
mark_page_accessed(page);
+ } else {
+ page = ZERO_PAGE(0);
+ page_cache_get(page);
}
/*
return desc.error;
}
-static int shmem_statfs(struct super_block *sb, struct kstatfs *buf)
+static int shmem_statfs(struct dentry *dentry, struct kstatfs *buf)
{
- struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
+ struct shmem_sb_info *sbinfo = SHMEM_SB(dentry->d_sb);
- buf->f_type = TMPFS_MAGIC;
+ buf->f_type = TMPFS_SUPER_MAGIC;
buf->f_bsize = PAGE_CACHE_SIZE;
+ buf->f_namelen = NAME_MAX;
spin_lock(&sbinfo->stat_lock);
- buf->f_blocks = sbinfo->max_blocks;
- buf->f_bavail = buf->f_bfree = sbinfo->free_blocks;
- buf->f_files = sbinfo->max_inodes;
- buf->f_ffree = sbinfo->free_inodes;
+ if (sbinfo->max_blocks) {
+ buf->f_blocks = sbinfo->max_blocks;
+ buf->f_bavail = buf->f_bfree = sbinfo->free_blocks;
+ }
+ if (sbinfo->max_inodes) {
+ buf->f_files = sbinfo->max_inodes;
+ buf->f_ffree = sbinfo->free_inodes;
+ }
+ /* else leave those fields 0 like simple_statfs */
spin_unlock(&sbinfo->stat_lock);
- buf->f_namelen = NAME_MAX;
return 0;
}
int error = -ENOSPC;
if (inode) {
+ error = security_inode_init_security(inode, dir, NULL, NULL,
+ NULL);
+ if (error) {
+ if (error != -EOPNOTSUPP) {
+ iput(inode);
+ return error;
+ }
+ }
+ error = shmem_acl_init(inode, dir);
+ if (error) {
+ iput(inode);
+ return error;
+ }
if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
dir->i_ctime = dir->i_mtime = CURRENT_TIME;
d_instantiate(dentry, inode);
dget(dentry); /* Extra count - pin the dentry in core */
- error = 0;
}
return error;
}
if ((error = shmem_mknod(dir, dentry, mode | S_IFDIR, 0)))
return error;
- dir->i_nlink++;
+ inc_nlink(dir);
return 0;
}
static int shmem_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
{
struct inode *inode = old_dentry->d_inode;
+ struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
+
+ /*
+ * No ordinary (disk based) filesystem counts links as inodes;
+ * but each new link needs a new dentry, pinning lowmem, and
+ * tmpfs dentries cannot be pruned until they are unlinked.
+ */
+ if (sbinfo->max_inodes) {
+ spin_lock(&sbinfo->stat_lock);
+ if (!sbinfo->free_inodes) {
+ spin_unlock(&sbinfo->stat_lock);
+ return -ENOSPC;
+ }
+ sbinfo->free_inodes--;
+ spin_unlock(&sbinfo->stat_lock);
+ }
dir->i_size += BOGO_DIRENT_SIZE;
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
- inode->i_nlink++;
+ inc_nlink(inode);
atomic_inc(&inode->i_count); /* New dentry reference */
dget(dentry); /* Extra pinning count for the created dentry */
d_instantiate(dentry, inode);
{
struct inode *inode = dentry->d_inode;
+ if (inode->i_nlink > 1 && !S_ISDIR(inode->i_mode)) {
+ struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
+ if (sbinfo->max_inodes) {
+ spin_lock(&sbinfo->stat_lock);
+ sbinfo->free_inodes++;
+ spin_unlock(&sbinfo->stat_lock);
+ }
+ }
+
dir->i_size -= BOGO_DIRENT_SIZE;
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
- inode->i_nlink--;
+ drop_nlink(inode);
dput(dentry); /* Undo the count from "create" - this does all the work */
return 0;
}
if (!simple_empty(dentry))
return -ENOTEMPTY;
- dir->i_nlink--;
+ drop_nlink(dentry->d_inode);
+ drop_nlink(dir);
return shmem_unlink(dir, dentry);
}
if (new_dentry->d_inode) {
(void) shmem_unlink(new_dir, new_dentry);
if (they_are_dirs)
- old_dir->i_nlink--;
+ drop_nlink(old_dir);
} else if (they_are_dirs) {
- old_dir->i_nlink--;
- new_dir->i_nlink++;
+ drop_nlink(old_dir);
+ inc_nlink(new_dir);
}
old_dir->i_size -= BOGO_DIRENT_SIZE;
if (!inode)
return -ENOSPC;
+ error = security_inode_init_security(inode, dir, NULL, NULL,
+ NULL);
+ if (error) {
+ if (error != -EOPNOTSUPP) {
+ iput(inode);
+ return error;
+ }
+ error = 0;
+ }
+
info = SHMEM_I(inode);
inode->i_size = len-1;
if (len <= (char *)inode - (char *)info) {
return error;
}
inode->i_op = &shmem_symlink_inode_operations;
- spin_lock(&shmem_ilock);
- list_add_tail(&info->list, &shmem_inodes);
- spin_unlock(&shmem_ilock);
kaddr = kmap_atomic(page, KM_USER0);
memcpy(kaddr, symname, len);
kunmap_atomic(kaddr, KM_USER0);
return 0;
}
-static int shmem_follow_link_inline(struct dentry *dentry, struct nameidata *nd)
+static void *shmem_follow_link_inline(struct dentry *dentry, struct nameidata *nd)
{
nd_set_link(nd, (char *)SHMEM_I(dentry->d_inode));
- return 0;
+ return NULL;
}
-static int shmem_follow_link(struct dentry *dentry, struct nameidata *nd)
+static void *shmem_follow_link(struct dentry *dentry, struct nameidata *nd)
{
struct page *page = NULL;
int res = shmem_getpage(dentry->d_inode, 0, &page, SGP_READ, NULL);
nd_set_link(nd, res ? ERR_PTR(res) : kmap(page));
- return 0;
+ return page;
}
-static void shmem_put_link(struct dentry *dentry, struct nameidata *nd)
+static void shmem_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
{
if (!IS_ERR(nd_get_link(nd))) {
- struct page *page;
-
- page = find_get_page(dentry->d_inode->i_mapping, 0);
- if (!page)
- BUG();
+ struct page *page = cookie;
kunmap(page);
mark_page_accessed(page);
page_cache_release(page);
- page_cache_release(page);
}
}
.put_link = shmem_put_link,
};
-static int shmem_parse_options(char *options, int *mode, uid_t *uid, gid_t *gid, unsigned long *blocks, unsigned long *inodes)
+#ifdef CONFIG_TMPFS_POSIX_ACL
+/**
+ * Superblocks without xattr inode operations will get security.* xattr
+ * support from the VFS "for free". As soon as we have any other xattrs
+ * like ACLs, we also need to implement the security.* handlers at
+ * filesystem level, though.
+ */
+
+static size_t shmem_xattr_security_list(struct inode *inode, char *list,
+ size_t list_len, const char *name,
+ size_t name_len)
+{
+ return security_inode_listsecurity(inode, list, list_len);
+}
+
+static int shmem_xattr_security_get(struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ return security_inode_getsecurity(inode, name, buffer, size,
+ -EOPNOTSUPP);
+}
+
+static int shmem_xattr_security_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ return security_inode_setsecurity(inode, name, value, size, flags);
+}
+
+static struct xattr_handler shmem_xattr_security_handler = {
+ .prefix = XATTR_SECURITY_PREFIX,
+ .list = shmem_xattr_security_list,
+ .get = shmem_xattr_security_get,
+ .set = shmem_xattr_security_set,
+};
+
+static struct xattr_handler *shmem_xattr_handlers[] = {
+ &shmem_xattr_acl_access_handler,
+ &shmem_xattr_acl_default_handler,
+ &shmem_xattr_security_handler,
+ NULL
+};
+#endif
+
+static struct dentry *shmem_get_parent(struct dentry *child)
+{
+ return ERR_PTR(-ESTALE);
+}
+
+static int shmem_match(struct inode *ino, void *vfh)
+{
+ __u32 *fh = vfh;
+ __u64 inum = fh[2];
+ inum = (inum << 32) | fh[1];
+ return ino->i_ino == inum && fh[0] == ino->i_generation;
+}
+
+static struct dentry *shmem_get_dentry(struct super_block *sb, void *vfh)
+{
+ struct dentry *de = NULL;
+ struct inode *inode;
+ __u32 *fh = vfh;
+ __u64 inum = fh[2];
+ inum = (inum << 32) | fh[1];
+
+ inode = ilookup5(sb, (unsigned long)(inum+fh[0]), shmem_match, vfh);
+ if (inode) {
+ de = d_find_alias(inode);
+ iput(inode);
+ }
+
+ return de? de: ERR_PTR(-ESTALE);
+}
+
+static struct dentry *shmem_decode_fh(struct super_block *sb, __u32 *fh,
+ int len, int type,
+ int (*acceptable)(void *context, struct dentry *de),
+ void *context)
+{
+ if (len < 3)
+ return ERR_PTR(-ESTALE);
+
+ return sb->s_export_op->find_exported_dentry(sb, fh, NULL, acceptable,
+ context);
+}
+
+static int shmem_encode_fh(struct dentry *dentry, __u32 *fh, int *len,
+ int connectable)
+{
+ struct inode *inode = dentry->d_inode;
+
+ if (*len < 3)
+ return 255;
+
+ if (hlist_unhashed(&inode->i_hash)) {
+ /* Unfortunately insert_inode_hash is not idempotent,
+ * so as we hash inodes here rather than at creation
+ * time, we need a lock to ensure we only try
+ * to do it once
+ */
+ static DEFINE_SPINLOCK(lock);
+ spin_lock(&lock);
+ if (hlist_unhashed(&inode->i_hash))
+ __insert_inode_hash(inode,
+ inode->i_ino + inode->i_generation);
+ spin_unlock(&lock);
+ }
+
+ fh[0] = inode->i_generation;
+ fh[1] = inode->i_ino;
+ fh[2] = ((__u64)inode->i_ino) >> 32;
+
+ *len = 3;
+ return 1;
+}
+
+static struct export_operations shmem_export_ops = {
+ .get_parent = shmem_get_parent,
+ .get_dentry = shmem_get_dentry,
+ .encode_fh = shmem_encode_fh,
+ .decode_fh = shmem_decode_fh,
+};
+
+static int shmem_parse_options(char *options, int *mode, uid_t *uid,
+ gid_t *gid, unsigned long *blocks, unsigned long *inodes,
+ int *policy, nodemask_t *policy_nodes)
{
char *this_char, *value, *rest;
- while ((this_char = strsep(&options, ",")) != NULL) {
+ while (options != NULL) {
+ this_char = options;
+ for (;;) {
+ /*
+ * NUL-terminate this option: unfortunately,
+ * mount options form a comma-separated list,
+ * but mpol's nodelist may also contain commas.
+ */
+ options = strchr(options, ',');
+ if (options == NULL)
+ break;
+ options++;
+ if (!isdigit(*options)) {
+ options[-1] = '\0';
+ break;
+ }
+ }
if (!*this_char)
continue;
if ((value = strchr(this_char,'=')) != NULL) {
*gid = simple_strtoul(value,&rest,0);
if (*rest)
goto bad_val;
+ } else if (!strcmp(this_char,"mpol")) {
+ if (shmem_parse_mpol(value,policy,policy_nodes))
+ goto bad_val;
} else {
printk(KERN_ERR "tmpfs: Bad mount option %s\n",
this_char);
struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
unsigned long max_blocks = sbinfo->max_blocks;
unsigned long max_inodes = sbinfo->max_inodes;
+ int policy = sbinfo->policy;
+ nodemask_t policy_nodes = sbinfo->policy_nodes;
+ unsigned long blocks;
+ unsigned long inodes;
+ int error = -EINVAL;
+
+ if (shmem_parse_options(data, NULL, NULL, NULL, &max_blocks,
+ &max_inodes, &policy, &policy_nodes))
+ return error;
- if (shmem_parse_options(data, NULL, NULL, NULL, &max_blocks, &max_inodes))
- return -EINVAL;
- return shmem_set_size(sbinfo, max_blocks, max_inodes);
+ spin_lock(&sbinfo->stat_lock);
+ blocks = sbinfo->max_blocks - sbinfo->free_blocks;
+ inodes = sbinfo->max_inodes - sbinfo->free_inodes;
+ if (max_blocks < blocks)
+ goto out;
+ if (max_inodes < inodes)
+ goto out;
+ /*
+ * Those tests also disallow limited->unlimited while any are in
+ * use, so i_blocks will always be zero when max_blocks is zero;
+ * but we must separately disallow unlimited->limited, because
+ * in that case we have no record of how much is already in use.
+ */
+ if (max_blocks && !sbinfo->max_blocks)
+ goto out;
+ if (max_inodes && !sbinfo->max_inodes)
+ goto out;
+
+ error = 0;
+ sbinfo->max_blocks = max_blocks;
+ sbinfo->free_blocks = max_blocks - blocks;
+ sbinfo->max_inodes = max_inodes;
+ sbinfo->free_inodes = max_inodes - inodes;
+ sbinfo->policy = policy;
+ sbinfo->policy_nodes = policy_nodes;
+out:
+ spin_unlock(&sbinfo->stat_lock);
+ return error;
}
#endif
+static void shmem_put_super(struct super_block *sb)
+{
+ kfree(sb->s_fs_info);
+ sb->s_fs_info = NULL;
+}
+
static int shmem_fill_super(struct super_block *sb,
void *data, int silent)
{
struct inode *inode;
struct dentry *root;
- unsigned long blocks, inodes;
int mode = S_IRWXUGO | S_ISVTX;
uid_t uid = current->fsuid;
gid_t gid = current->fsgid;
- struct shmem_sb_info *sbinfo;
int err = -ENOMEM;
+ struct shmem_sb_info *sbinfo;
+ unsigned long blocks = 0;
+ unsigned long inodes = 0;
+ int policy = MPOL_DEFAULT;
+ nodemask_t policy_nodes = node_online_map;
- sbinfo = kmalloc(sizeof(struct shmem_sb_info), GFP_KERNEL);
- if (!sbinfo)
- return -ENOMEM;
- sb->s_fs_info = sbinfo;
- memset(sbinfo, 0, sizeof(struct shmem_sb_info));
-
+#ifdef CONFIG_TMPFS
/*
* Per default we only allow half of the physical ram per
- * tmpfs instance
+ * tmpfs instance, limiting inodes to one per page of lowmem;
+ * but the internal instance is left unlimited.
*/
- blocks = inodes = totalram_pages / 2;
-
-#ifdef CONFIG_TMPFS
- if (shmem_parse_options(data, &mode, &uid, &gid, &blocks, &inodes)) {
- err = -EINVAL;
- goto failed;
+ if (!(sb->s_flags & MS_NOUSER)) {
+ blocks = totalram_pages / 2;
+ inodes = totalram_pages - totalhigh_pages;
+ if (inodes > blocks)
+ inodes = blocks;
+ if (shmem_parse_options(data, &mode, &uid, &gid, &blocks,
+ &inodes, &policy, &policy_nodes))
+ return -EINVAL;
}
+ sb->s_export_op = &shmem_export_ops;
#else
sb->s_flags |= MS_NOUSER;
#endif
+ /* Round up to L1_CACHE_BYTES to resist false sharing */
+ sbinfo = kmalloc(max((int)sizeof(struct shmem_sb_info),
+ L1_CACHE_BYTES), GFP_KERNEL);
+ if (!sbinfo)
+ return -ENOMEM;
+
spin_lock_init(&sbinfo->stat_lock);
sbinfo->max_blocks = blocks;
sbinfo->free_blocks = blocks;
sbinfo->max_inodes = inodes;
sbinfo->free_inodes = inodes;
+ sbinfo->policy = policy;
+ sbinfo->policy_nodes = policy_nodes;
+
+ sb->s_fs_info = sbinfo;
sb->s_maxbytes = SHMEM_MAX_BYTES;
sb->s_blocksize = PAGE_CACHE_SIZE;
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
- sb->s_magic = TMPFS_MAGIC;
+ sb->s_magic = TMPFS_SUPER_MAGIC;
sb->s_op = &shmem_ops;
+ sb->s_time_gran = 1;
+#ifdef CONFIG_TMPFS_POSIX_ACL
+ sb->s_xattr = shmem_xattr_handlers;
+ sb->s_flags |= MS_POSIXACL;
+#endif
+
inode = shmem_get_inode(sb, S_IFDIR | mode, 0);
if (!inode)
goto failed;
failed_iput:
iput(inode);
failed:
- kfree(sbinfo);
- sb->s_fs_info = NULL;
+ shmem_put_super(sb);
return err;
}
-static void shmem_put_super(struct super_block *sb)
-{
- kfree(sb->s_fs_info);
- sb->s_fs_info = NULL;
-}
-
-static kmem_cache_t *shmem_inode_cachep;
+static struct kmem_cache *shmem_inode_cachep;
static struct inode *shmem_alloc_inode(struct super_block *sb)
{
struct shmem_inode_info *p;
- p = (struct shmem_inode_info *)kmem_cache_alloc(shmem_inode_cachep, SLAB_KERNEL);
+ p = (struct shmem_inode_info *)kmem_cache_alloc(shmem_inode_cachep, GFP_KERNEL);
if (!p)
return NULL;
return &p->vfs_inode;
static void shmem_destroy_inode(struct inode *inode)
{
- mpol_free_shared_policy(&SHMEM_I(inode)->policy);
+ if ((inode->i_mode & S_IFMT) == S_IFREG) {
+ /* only struct inode is valid if it's an inline symlink */
+ mpol_free_shared_policy(&SHMEM_I(inode)->policy);
+ }
+ shmem_acl_destroy_inode(inode);
kmem_cache_free(shmem_inode_cachep, SHMEM_I(inode));
}
-static void init_once(void *foo, kmem_cache_t *cachep, unsigned long flags)
+static void init_once(void *foo, struct kmem_cache *cachep,
+ unsigned long flags)
{
struct shmem_inode_info *p = (struct shmem_inode_info *) foo;
if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
SLAB_CTOR_CONSTRUCTOR) {
inode_init_once(&p->vfs_inode);
+#ifdef CONFIG_TMPFS_POSIX_ACL
+ p->i_acl = NULL;
+ p->i_default_acl = NULL;
+#endif
}
}
{
shmem_inode_cachep = kmem_cache_create("shmem_inode_cache",
sizeof(struct shmem_inode_info),
- 0, SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT,
- init_once, NULL);
+ 0, 0, init_once, NULL);
if (shmem_inode_cachep == NULL)
return -ENOMEM;
return 0;
static void destroy_inodecache(void)
{
- if (kmem_cache_destroy(shmem_inode_cachep))
- printk(KERN_INFO "shmem_inode_cache: not all structures were freed\n");
+ kmem_cache_destroy(shmem_inode_cachep);
}
-static struct address_space_operations shmem_aops = {
+static const struct address_space_operations shmem_aops = {
.writepage = shmem_writepage,
.set_page_dirty = __set_page_dirty_nobuffers,
#ifdef CONFIG_TMPFS
.prepare_write = shmem_prepare_write,
.commit_write = simple_commit_write,
#endif
+ .migratepage = migrate_page,
};
-static struct file_operations shmem_file_operations = {
+static const struct file_operations shmem_file_operations = {
.mmap = shmem_mmap,
#ifdef CONFIG_TMPFS
.llseek = generic_file_llseek,
static struct inode_operations shmem_inode_operations = {
.truncate = shmem_truncate,
.setattr = shmem_notify_change,
+ .truncate_range = shmem_truncate_range,
+#ifdef CONFIG_TMPFS_POSIX_ACL
+ .setxattr = generic_setxattr,
+ .getxattr = generic_getxattr,
+ .listxattr = generic_listxattr,
+ .removexattr = generic_removexattr,
+ .permission = shmem_permission,
+#endif
+
};
static struct inode_operations shmem_dir_inode_operations = {
.mknod = shmem_mknod,
.rename = shmem_rename,
#endif
+#ifdef CONFIG_TMPFS_POSIX_ACL
+ .setattr = shmem_notify_change,
+ .setxattr = generic_setxattr,
+ .getxattr = generic_getxattr,
+ .listxattr = generic_listxattr,
+ .removexattr = generic_removexattr,
+ .permission = shmem_permission,
+#endif
+};
+
+static struct inode_operations shmem_special_inode_operations = {
+#ifdef CONFIG_TMPFS_POSIX_ACL
+ .setattr = shmem_notify_change,
+ .setxattr = generic_setxattr,
+ .getxattr = generic_getxattr,
+ .listxattr = generic_listxattr,
+ .removexattr = generic_removexattr,
+ .permission = shmem_permission,
+#endif
};
static struct super_operations shmem_ops = {
#endif
};
-static struct super_block *shmem_get_sb(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data)
+
+static int shmem_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
- return get_sb_nodev(fs_type, flags, data, shmem_fill_super);
+ return get_sb_nodev(fs_type, flags, data, shmem_fill_super, mnt);
}
static struct file_system_type tmpfs_fs_type = {
printk(KERN_ERR "Could not register tmpfs\n");
goto out2;
}
-#ifdef CONFIG_TMPFS
- devfs_mk_dir("shm");
-#endif
- shm_mnt = kern_mount(&tmpfs_fs_type);
+
+ shm_mnt = vfs_kern_mount(&tmpfs_fs_type, MS_NOUSER,
+ tmpfs_fs_type.name, NULL);
if (IS_ERR(shm_mnt)) {
error = PTR_ERR(shm_mnt);
printk(KERN_ERR "Could not kern_mount tmpfs\n");
goto out1;
}
-
- /* The internal instance should not do size checking */
- shmem_set_size(SHMEM_SB(shm_mnt->mnt_sb), ULONG_MAX, ULONG_MAX);
return 0;
out1:
if (IS_ERR(shm_mnt))
return (void *)shm_mnt;
- if (size > SHMEM_MAX_BYTES)
+ if (size < 0 || size > SHMEM_MAX_BYTES)
return ERR_PTR(-EINVAL);
if (shmem_acct_size(flags, size))
d_instantiate(dentry, inode);
inode->i_size = size;
inode->i_nlink = 0; /* It is unlinked */
- file->f_vfsmnt = mntget(shm_mnt);
- file->f_dentry = dentry;
+ file->f_path.mnt = mntget(shm_mnt);
+ file->f_path.dentry = dentry;
file->f_mapping = inode->i_mapping;
file->f_op = &shmem_file_operations;
file->f_mode = FMODE_WRITE | FMODE_READ;
- return(file);
+ return file;
close_file:
put_filp(file);
vma->vm_ops = &shmem_vm_ops;
return 0;
}
-
-EXPORT_SYMBOL(shmem_file_setup);