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Diffstat (limited to 'mm/shmem.c')
-rw-r--r--mm/shmem.c88
1 files changed, 56 insertions, 32 deletions
diff --git a/mm/shmem.c b/mm/shmem.c
index d88bf98f0..8c5467e4e 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -110,9 +110,13 @@ static unsigned long shmem_default_max_blocks(void)
return totalram_pages / 2;
}
-static unsigned long shmem_default_max_inodes(void)
+static int shmem_default_max_inodes(void)
{
- return min(totalram_pages - totalhigh_pages, totalram_pages / 2);
+ unsigned long ul;
+
+ ul = INT_MAX;
+ ul = min3(ul, totalram_pages - totalhigh_pages, totalram_pages / 2);
+ return ul;
}
#endif
@@ -587,6 +591,7 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr)
static void shmem_evict_inode(struct inode *inode)
{
struct shmem_inode_info *info = SHMEM_I(inode);
+ struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
if (inode->i_mapping->a_ops == &shmem_aops) {
shmem_unacct_size(info->flags, inode->i_size);
@@ -602,6 +607,11 @@ static void shmem_evict_inode(struct inode *inode)
simple_xattrs_free(&info->xattrs);
WARN_ON(inode->i_blocks);
+ if (!sbinfo->idr_nouse && inode->i_ino) {
+ mutex_lock(&sbinfo->idr_lock);
+ idr_remove(&sbinfo->idr, inode->i_ino);
+ mutex_unlock(&sbinfo->idr_lock);
+ }
shmem_free_inode(inode->i_sb);
clear_inode(inode);
}
@@ -1401,13 +1411,13 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
struct inode *inode;
struct shmem_inode_info *info;
struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
+ int ino;
if (shmem_reserve_inode(sb))
return NULL;
inode = new_inode(sb);
if (inode) {
- inode->i_ino = get_next_ino();
inode_init_owner(inode, dir, mode);
inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
@@ -1450,6 +1460,25 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
mpol_shared_policy_init(&info->policy, NULL);
break;
}
+
+ if (!sbinfo->idr_nouse) {
+ /* inum 0 and 1 are unused */
+ mutex_lock(&sbinfo->idr_lock);
+ ino = idr_alloc(&sbinfo->idr, inode, 2, INT_MAX,
+ GFP_NOFS);
+ if (ino > 0) {
+ inode->i_ino = ino;
+ mutex_unlock(&sbinfo->idr_lock);
+ __insert_inode_hash(inode, inode->i_ino);
+ } else {
+ inode->i_ino = 0;
+ mutex_unlock(&sbinfo->idr_lock);
+ iput(inode);
+ /* shmem_free_inode() will be called */
+ inode = NULL;
+ }
+ } else
+ inode->i_ino = get_next_ino();
} else
shmem_free_inode(sb);
return inode;
@@ -2667,8 +2696,7 @@ static struct dentry *shmem_get_parent(struct dentry *child)
static int shmem_match(struct inode *ino, void *vfh)
{
__u32 *fh = vfh;
- __u64 inum = fh[2];
- inum = (inum << 32) | fh[1];
+ __u64 inum = fh[1];
return ino->i_ino == inum && fh[0] == ino->i_generation;
}
@@ -2679,14 +2707,11 @@ static struct dentry *shmem_fh_to_dentry(struct super_block *sb,
struct dentry *dentry = NULL;
u64 inum;
- if (fh_len < 3)
+ if (fh_len < 2)
return NULL;
- inum = fid->raw[2];
- inum = (inum << 32) | fid->raw[1];
-
- inode = ilookup5(sb, (unsigned long)(inum + fid->raw[0]),
- shmem_match, fid->raw);
+ inum = fid->raw[1];
+ inode = ilookup5(sb, inum, shmem_match, fid->raw);
if (inode) {
dentry = d_find_alias(inode);
iput(inode);
@@ -2698,30 +2723,15 @@ static struct dentry *shmem_fh_to_dentry(struct super_block *sb,
static int shmem_encode_fh(struct inode *inode, __u32 *fh, int *len,
struct inode *parent)
{
- if (*len < 3) {
- *len = 3;
+ if (*len < 2) {
+ *len = 2;
return FILEID_INVALID;
}
- if (inode_unhashed(inode)) {
- /* 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 (inode_unhashed(inode))
- __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;
+ *len = 2;
return 1;
}
@@ -2786,7 +2796,7 @@ static int shmem_parse_options(char *options, struct shmem_sb_info *sbinfo,
goto bad_val;
} else if (!strcmp(this_char,"nr_inodes")) {
sbinfo->max_inodes = memparse(value, &rest);
- if (*rest)
+ if (*rest || sbinfo->max_inodes < 2)
goto bad_val;
} else if (!strcmp(this_char,"mode")) {
if (remount)
@@ -2839,7 +2849,7 @@ static int shmem_remount_fs(struct super_block *sb, int *flags, char *data)
{
struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
struct shmem_sb_info config = *sbinfo;
- unsigned long inodes;
+ int inodes;
int error = -EINVAL;
config.mpol = NULL;
@@ -2887,7 +2897,7 @@ static int shmem_show_options(struct seq_file *seq, struct dentry *root)
seq_printf(seq, ",size=%luk",
sbinfo->max_blocks << (PAGE_CACHE_SHIFT - 10));
if (sbinfo->max_inodes != shmem_default_max_inodes())
- seq_printf(seq, ",nr_inodes=%lu", sbinfo->max_inodes);
+ seq_printf(seq, ",nr_inodes=%d", sbinfo->max_inodes);
if (sbinfo->mode != (S_IRWXUGO | S_ISVTX))
seq_printf(seq, ",mode=%03ho", sbinfo->mode);
if (!uid_eq(sbinfo->uid, GLOBAL_ROOT_UID))
@@ -2976,6 +2986,8 @@ static void shmem_put_super(struct super_block *sb)
{
struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
+ if (!sbinfo->idr_nouse)
+ idr_destroy(&sbinfo->idr);
percpu_counter_destroy(&sbinfo->used_blocks);
mpol_put(sbinfo->mpol);
kfree(sbinfo);
@@ -2994,6 +3006,8 @@ int shmem_fill_super(struct super_block *sb, void *data, int silent)
if (!sbinfo)
return -ENOMEM;
+ mutex_init(&sbinfo->idr_lock);
+ idr_init(&sbinfo->idr);
sbinfo->mode = S_IRWXUGO | S_ISVTX;
sbinfo->uid = current_fsuid();
sbinfo->gid = current_fsgid();
@@ -3097,6 +3111,15 @@ static void shmem_destroy_inodecache(void)
kmem_cache_destroy(shmem_inode_cachep);
}
+static __init void shmem_no_idr(struct super_block *sb)
+{
+ struct shmem_sb_info *sbinfo;
+
+ sbinfo = SHMEM_SB(sb);
+ sbinfo->idr_nouse = true;
+ idr_destroy(&sbinfo->idr);
+}
+
static const struct address_space_operations shmem_aops = {
.writepage = shmem_writepage,
.set_page_dirty = __set_page_dirty_no_writeback,
@@ -3232,6 +3255,7 @@ int __init shmem_init(void)
printk(KERN_ERR "Could not kern_mount tmpfs\n");
goto out1;
}
+ shmem_no_idr(shm_mnt->mnt_sb);
return 0;
out1:
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-13 19:45:59 +0000