shmem: factor out sbi->free_inodes manipulations
The shmem_sb_info structure has a number of free_inodes. This
value is altered in appropriate places under spinlock and with
the sbi->max_inodes != 0 check.
Consolidate these manipulations into two helpers.
This is minus 42 bytes of shmem.o and minus 4 :) lines of code.
[akpm@linux-foundation.org: fix error return values]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/shmem.c b/mm/shmem.c
index 5dfe790..ce64b66 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -205,6 +205,31 @@
}
}
+static int shmem_reserve_inode(struct super_block *sb)
+{
+ struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
+ 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);
+ }
+ return 0;
+}
+
+static void shmem_free_inode(struct super_block *sb)
+{
+ struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
+ if (sbinfo->max_inodes) {
+ spin_lock(&sbinfo->stat_lock);
+ sbinfo->free_inodes++;
+ spin_unlock(&sbinfo->stat_lock);
+ }
+}
+
/*
* shmem_recalc_inode - recalculate the size of an inode
*
@@ -762,7 +787,6 @@
static void shmem_delete_inode(struct inode *inode)
{
- struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
struct shmem_inode_info *info = SHMEM_I(inode);
if (inode->i_op->truncate == shmem_truncate) {
@@ -777,11 +801,7 @@
}
}
BUG_ON(inode->i_blocks);
- if (sbinfo->max_inodes) {
- spin_lock(&sbinfo->stat_lock);
- sbinfo->free_inodes++;
- spin_unlock(&sbinfo->stat_lock);
- }
+ shmem_free_inode(inode->i_sb);
clear_inode(inode);
}
@@ -1371,15 +1391,8 @@
struct shmem_inode_info *info;
struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
- 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);
- }
+ if (shmem_reserve_inode(sb))
+ return NULL;
inode = new_inode(sb);
if (inode) {
@@ -1423,11 +1436,8 @@
NULL);
break;
}
- } else if (sbinfo->max_inodes) {
- spin_lock(&sbinfo->stat_lock);
- sbinfo->free_inodes++;
- spin_unlock(&sbinfo->stat_lock);
- }
+ } else
+ shmem_free_inode(sb);
return inode;
}
@@ -1670,22 +1680,16 @@
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);
+ int ret;
/*
* 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);
- }
+ ret = shmem_reserve_inode(inode->i_sb);
+ if (ret)
+ goto out;
dir->i_size += BOGO_DIRENT_SIZE;
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
@@ -1693,21 +1697,16 @@
atomic_inc(&inode->i_count); /* New dentry reference */
dget(dentry); /* Extra pinning count for the created dentry */
d_instantiate(dentry, inode);
- return 0;
+out:
+ return ret;
}
static int shmem_unlink(struct inode *dir, struct dentry *dentry)
{
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);
- }
- }
+ if (inode->i_nlink > 1 && !S_ISDIR(inode->i_mode))
+ shmem_free_inode(inode->i_sb);
dir->i_size -= BOGO_DIRENT_SIZE;
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;