openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: new helper - d_make_root()
  dcache: use a dispose list in select_parent
  ceph: d_alloc_root() may fail
  ext4: fix failure exits
  isofs: inode leak on mount failure
This commit is contained in:
Linus Torvalds 2012-01-09 17:37:37 -08:00
parent 37cfc3f67d adc0e91ab1
commit e4e11180df
5 changed files with 63 additions and 53 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
fs/ceph/super.c
View File

@ -636,19 +636,26 @@ static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
req->r_num_caps = 2;
err = ceph_mdsc_do_request(mdsc, NULL, req);
if (err == 0) {
struct inode *inode = req->r_target_inode;
req->r_target_inode = NULL;
dout("open_root_inode success\n");
if (ceph_ino(req->r_target_inode) == CEPH_INO_ROOT &&
if (ceph_ino(inode) == CEPH_INO_ROOT &&
fsc->sb->s_root == NULL) {
root = d_alloc_root(req->r_target_inode);
root = d_alloc_root(inode);
if (!root) {
iput(inode);
root = ERR_PTR(-ENOMEM);
goto out;
}
ceph_init_dentry(root);
} else {
root = d_obtain_alias(req->r_target_inode);
root = d_obtain_alias(inode);
}
req->r_target_inode = NULL;
dout("open_root_inode success, root dentry is %p\n", root);
} else {
root = ERR_PTR(err);
}
out:
ceph_mdsc_put_request(req);
return root;
}

80
fs/dcache.c
View File

@ -276,15 +276,15 @@ static void dentry_lru_prune(struct dentry *dentry)
}
}
static void dentry_lru_move_tail(struct dentry *dentry)
static void dentry_lru_move_list(struct dentry *dentry, struct list_head *list)
{
spin_lock(&dcache_lru_lock);
if (list_empty(&dentry->d_lru)) {
list_add_tail(&dentry->d_lru, &dentry->d_sb->s_dentry_lru);
list_add_tail(&dentry->d_lru, list);
dentry->d_sb->s_nr_dentry_unused++;
dentry_stat.nr_unused++;
} else {
list_move_tail(&dentry->d_lru, &dentry->d_sb->s_dentry_lru);
list_move_tail(&dentry->d_lru, list);
}
spin_unlock(&dcache_lru_lock);
}
@ -770,14 +770,18 @@ static void shrink_dentry_list(struct list_head *list)
}
/**
* __shrink_dcache_sb - shrink the dentry LRU on a given superblock
* @sb: superblock to shrink dentry LRU.
* @count: number of entries to prune
* @flags: flags to control the dentry processing
* prune_dcache_sb - shrink the dcache
* @sb: superblock
* @count: number of entries to try to free
*
* If flags contains DCACHE_REFERENCED reference dentries will not be pruned.
* Attempt to shrink the superblock dcache LRU by @count entries. This is
* done when we need more memory an called from the superblock shrinker
* function.
*
* This function may fail to free any resources if all the dentries are in
* use.
*/
static void __shrink_dcache_sb(struct super_block *sb, int count, int flags)
void prune_dcache_sb(struct super_block *sb, int count)
{
struct dentry *dentry;
LIST_HEAD(referenced);
@ -796,13 +800,7 @@ static void __shrink_dcache_sb(struct super_block *sb, int count, int flags)
goto relock;
}
/*
* If we are honouring the DCACHE_REFERENCED flag and the
* dentry has this flag set, don't free it. Clear the flag
* and put it back on the LRU.
*/
if (flags & DCACHE_REFERENCED &&
dentry->d_flags & DCACHE_REFERENCED) {
if (dentry->d_flags & DCACHE_REFERENCED) {
dentry->d_flags &= ~DCACHE_REFERENCED;
list_move(&dentry->d_lru, &referenced);
spin_unlock(&dentry->d_lock);
@ -821,23 +819,6 @@ static void __shrink_dcache_sb(struct super_block *sb, int count, int flags)
shrink_dentry_list(&tmp);
}
/**
* prune_dcache_sb - shrink the dcache
* @sb: superblock
* @nr_to_scan: number of entries to try to free
*
* Attempt to shrink the superblock dcache LRU by @nr_to_scan entries. This is
* done when we need more memory an called from the superblock shrinker
* function.
*
* This function may fail to free any resources if all the dentries are in
* use.
*/
void prune_dcache_sb(struct super_block *sb, int nr_to_scan)
{
__shrink_dcache_sb(sb, nr_to_scan, DCACHE_REFERENCED);
}
/**
* shrink_dcache_sb - shrink dcache for a superblock
* @sb: superblock
@ -1092,7 +1073,7 @@ EXPORT_SYMBOL(have_submounts);
* drop the lock and return early due to latency
* constraints.
*/
static int select_parent(struct dentry * parent)
static int select_parent(struct dentry *parent, struct list_head *dispose)
{
struct dentry *this_parent;
struct list_head *next;
@ -1114,12 +1095,11 @@ static int select_parent(struct dentry * parent)
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
/*
* move only zero ref count dentries to the end
* of the unused list for prune_dcache
/*
* move only zero ref count dentries to the dispose list.
*/
if (!dentry->d_count) {
dentry_lru_move_tail(dentry);
dentry_lru_move_list(dentry, dispose);
found++;
} else {
dentry_lru_del(dentry);
@ -1181,14 +1161,13 @@ static int select_parent(struct dentry * parent)
*
* Prune the dcache to remove unused children of the parent dentry.
*/
void shrink_dcache_parent(struct dentry * parent)
{
struct super_block *sb = parent->d_sb;
LIST_HEAD(dispose);
int found;
while ((found = select_parent(parent)) != 0)
__shrink_dcache_sb(sb, found, 0);
while ((found = select_parent(parent, &dispose)) != 0)
shrink_dentry_list(&dispose);
}
EXPORT_SYMBOL(shrink_dcache_parent);
@ -1461,6 +1440,23 @@ struct dentry * d_alloc_root(struct inode * root_inode)
}
EXPORT_SYMBOL(d_alloc_root);
struct dentry *d_make_root(struct inode *root_inode)
{
struct dentry *res = NULL;
if (root_inode) {
static const struct qstr name = { .name = "/", .len = 1 };
res = __d_alloc(root_inode->i_sb, &name);
if (res)
d_instantiate(res, root_inode);
else
iput(root_inode);
}
return res;
}
EXPORT_SYMBOL(d_make_root);
static struct dentry * __d_find_any_alias(struct inode *inode)
{
struct dentry *alias;

13
fs/ext4/super.c
View File

@ -3733,10 +3733,12 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
}
if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
iput(root);
goto failed_mount4;
}
sb->s_root = d_alloc_root(root);
if (!sb->s_root) {
iput(root);
ext4_msg(sb, KERN_ERR, "get root dentry failed");
ret = -ENOMEM;
goto failed_mount4;
@ -3773,7 +3775,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
if (err) {
ext4_msg(sb, KERN_ERR, "failed to initialize system "
"zone (%d)", err);
goto failed_mount4;
goto failed_mount4a;
}
ext4_ext_init(sb);
@ -3830,13 +3832,14 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
failed_mount7:
ext4_unregister_li_request(sb);
failed_mount6:
ext4_ext_release(sb);
failed_mount5:
ext4_mb_release(sb);
failed_mount5:
ext4_ext_release(sb);
ext4_release_system_zone(sb);
failed_mount4:
iput(root);
failed_mount4a:
dput(sb->s_root);
sb->s_root = NULL;
failed_mount4:
ext4_msg(sb, KERN_ERR, "mount failed");
destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
failed_mount_wq:

7
fs/isofs/inode.c
View File

@ -948,8 +948,11 @@ static int isofs_fill_super(struct super_block *s, void *data, int silent)
/* get the root dentry */
s->s_root = d_alloc_root(inode);
if (!(s->s_root))
goto out_no_root;
if (!(s->s_root)) {
iput(inode);
error = -ENOMEM;
goto out_no_inode;
}
kfree(opt.iocharset);

1
include/linux/dcache.h
View File

@ -249,6 +249,7 @@ extern int d_invalidate(struct dentry *);
/* only used at mount-time */
extern struct dentry * d_alloc_root(struct inode *);
extern struct dentry * d_make_root(struct inode *);
/* <clickety>-<click> the ramfs-type tree */
extern void d_genocide(struct dentry *);