From: Lukas Czerner <lczerner@xxxxxxxxxx>
Make shmem_get_inode() return ERR_PTR instead of NULL on error. This will be
useful later when we introduce quota support.
There should be no functional change.
Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx>
Signed-off-by: Carlos Maiolino <cmaiolino@xxxxxxxxxx>
---
V3:
- Fix shmem_get_inode() definition when CONFIG_SHMEM is not enabled
V2:
- Fix error handling logic in shmem_tmpfile()
- Add missing idmap argument to the ramfs version of
shmem_get_inode(), reported by Intel's
kernel test robot <lkp@xxxxxxxxx>
mm/shmem.c | 206 ++++++++++++++++++++++++++++++-----------------------
1 file changed, 116 insertions(+), 90 deletions(-)
diff --git a/mm/shmem.c b/mm/shmem.c
index b1b3b826f6189..09a44f1b2c954 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2354,65 +2354,71 @@ static struct inode *shmem_get_inode(struct mnt_idmap *idmap, struct super_block
struct shmem_inode_info *info;
struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
ino_t ino;
+ int err;
+
+ err = shmem_reserve_inode(sb, &ino);
+ if (err)
+ return ERR_PTR(err);
- if (shmem_reserve_inode(sb, &ino))
- return NULL;
inode = new_inode(sb);
- if (inode) {
- inode->i_ino = ino;
- inode_init_owner(idmap, inode, dir, mode);
- inode->i_blocks = 0;
- inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
- inode->i_generation = get_random_u32();
- info = SHMEM_I(inode);
- memset(info, 0, (char *)inode - (char *)info);
- spin_lock_init(&info->lock);
- atomic_set(&info->stop_eviction, 0);
- info->seals = F_SEAL_SEAL;
- info->flags = flags & VM_NORESERVE;
- info->i_crtime = inode->i_mtime;
- info->fsflags = (dir == NULL) ? 0 :
- SHMEM_I(dir)->fsflags & SHMEM_FL_INHERITED;
- if (info->fsflags)
- shmem_set_inode_flags(inode, info->fsflags);
- INIT_LIST_HEAD(&info->shrinklist);
- INIT_LIST_HEAD(&info->swaplist);
- simple_xattrs_init(&info->xattrs);
- cache_no_acl(inode);
- mapping_set_large_folios(inode->i_mapping);
-
- switch (mode & S_IFMT) {
- default:
- inode->i_op = &shmem_special_inode_operations;
- init_special_inode(inode, mode, dev);
- break;
- case S_IFREG:
- inode->i_mapping->a_ops = &shmem_aops;
- inode->i_op = &shmem_inode_operations;
- inode->i_fop = &shmem_file_operations;
- mpol_shared_policy_init(&info->policy,
- shmem_get_sbmpol(sbinfo));
- break;
- case S_IFDIR:
- 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, NULL);
- break;
- }
- lockdep_annotate_inode_mutex_key(inode);
- } else
+ if (!inode) {
shmem_free_inode(sb);
+ return ERR_PTR(-ENOSPC);
+ }
+
+ inode->i_ino = ino;
+ inode_init_owner(idmap, inode, dir, mode);
+ inode->i_blocks = 0;
+ inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
+ inode->i_generation = get_random_u32();
+ info = SHMEM_I(inode);
+ memset(info, 0, (char *)inode - (char *)info);
+ spin_lock_init(&info->lock);
+ atomic_set(&info->stop_eviction, 0);
+ info->seals = F_SEAL_SEAL;
+ info->flags = flags & VM_NORESERVE;
+ info->i_crtime = inode->i_mtime;
+ info->fsflags = (dir == NULL) ? 0 :
+ SHMEM_I(dir)->fsflags & SHMEM_FL_INHERITED;
+ if (info->fsflags)
+ shmem_set_inode_flags(inode, info->fsflags);
+ INIT_LIST_HEAD(&info->shrinklist);
+ INIT_LIST_HEAD(&info->swaplist);
+ simple_xattrs_init(&info->xattrs);
+ cache_no_acl(inode);
+ mapping_set_large_folios(inode->i_mapping);
+
+ switch (mode & S_IFMT) {
+ default:
+ inode->i_op = &shmem_special_inode_operations;
+ init_special_inode(inode, mode, dev);
+ break;
+ case S_IFREG:
+ inode->i_mapping->a_ops = &shmem_aops;
+ inode->i_op = &shmem_inode_operations;
+ inode->i_fop = &shmem_file_operations;
+ mpol_shared_policy_init(&info->policy,
+ shmem_get_sbmpol(sbinfo));
+ break;
+ case S_IFDIR:
+ 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, NULL);
+ break;
+ }
+
+ lockdep_annotate_inode_mutex_key(inode);
return inode;
}
@@ -2927,27 +2933,30 @@ shmem_mknod(struct mnt_idmap *idmap, struct inode *dir,
struct dentry *dentry, umode_t mode, dev_t dev)
{
struct inode *inode;
- int error = -ENOSPC;
+ int error;
inode = shmem_get_inode(idmap, dir->i_sb, dir, mode, dev, VM_NORESERVE);
- if (inode) {
- error = simple_acl_create(dir, inode);
- if (error)
- goto out_iput;
- error = security_inode_init_security(inode, dir,
- &dentry->d_name,
- shmem_initxattrs, NULL);
- if (error && error != -EOPNOTSUPP)
- goto out_iput;
- error = 0;
- dir->i_size += BOGO_DIRENT_SIZE;
- dir->i_ctime = dir->i_mtime = current_time(dir);
- inode_inc_iversion(dir);
- d_instantiate(dentry, inode);
- dget(dentry); /* Extra count - pin the dentry in core */
- }
+ if (IS_ERR(inode))
+ return PTR_ERR(inode);
+
+ error = simple_acl_create(dir, inode);
+ if (error)
+ goto out_iput;
+ error = security_inode_init_security(inode, dir,
+ &dentry->d_name,
+ shmem_initxattrs, NULL);
+ if (error && error != -EOPNOTSUPP)
+ goto out_iput;
+
+ error = 0;
+ dir->i_size += BOGO_DIRENT_SIZE;
+ dir->i_ctime = dir->i_mtime = current_time(dir);
+ inode_inc_iversion(dir);
+ d_instantiate(dentry, inode);
+ dget(dentry); /* Extra count - pin the dentry in core */
return error;
+
out_iput:
iput(inode);
return error;
@@ -2958,20 +2967,26 @@ shmem_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
struct file *file, umode_t mode)
{
struct inode *inode;
- int error = -ENOSPC;
+ int error;
inode = shmem_get_inode(idmap, dir->i_sb, dir, mode, 0, VM_NORESERVE);
- if (inode) {
- error = security_inode_init_security(inode, dir,
- NULL,
- shmem_initxattrs, NULL);
- if (error && error != -EOPNOTSUPP)
- goto out_iput;
- error = simple_acl_create(dir, inode);
- if (error)
- goto out_iput;
- d_tmpfile(file, inode);
+
+ if (IS_ERR(inode)) {
+ error = PTR_ERR(inode);
+ goto err_out;
}
+
+ error = security_inode_init_security(inode, dir,
+ NULL,
+ shmem_initxattrs, NULL);
+ if (error && error != -EOPNOTSUPP)
+ goto out_iput;
+ error = simple_acl_create(dir, inode);
+ if (error)
+ goto out_iput;
+ d_tmpfile(file, inode);
+
+err_out:
return finish_open_simple(file, error);
out_iput:
iput(inode);
@@ -3146,8 +3161,9 @@ static int shmem_symlink(struct mnt_idmap *idmap, struct inode *dir,
inode = shmem_get_inode(idmap, dir->i_sb, dir, S_IFLNK | 0777, 0,
VM_NORESERVE);
- if (!inode)
- return -ENOSPC;
+
+ if (IS_ERR(inode))
+ return PTR_ERR(inode);
error = security_inode_init_security(inode, dir, &dentry->d_name,
shmem_initxattrs, NULL);
@@ -3762,12 +3778,13 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
struct shmem_options *ctx = fc->fs_private;
struct inode *inode;
struct shmem_sb_info *sbinfo;
+ int error = -ENOMEM;
/* Round up to L1_CACHE_BYTES to resist false sharing */
sbinfo = kzalloc(max((int)sizeof(struct shmem_sb_info),
L1_CACHE_BYTES), GFP_KERNEL);
if (!sbinfo)
- return -ENOMEM;
+ return error;
sb->s_fs_info = sbinfo;
@@ -3829,8 +3846,10 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
inode = shmem_get_inode(&nop_mnt_idmap, sb, NULL, S_IFDIR | sbinfo->mode, 0,
VM_NORESERVE);
- if (!inode)
+ if (IS_ERR(inode)) {
+ error = PTR_ERR(inode);
goto failed;
+ }
inode->i_uid = sbinfo->uid;
inode->i_gid = sbinfo->gid;
sb->s_root = d_make_root(inode);
@@ -3840,7 +3859,7 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
failed:
shmem_put_super(sb);
- return -ENOMEM;
+ return error;
}
static int shmem_get_tree(struct fs_context *fc)
@@ -4209,10 +4228,16 @@ EXPORT_SYMBOL_GPL(shmem_truncate_range);
#define shmem_vm_ops generic_file_vm_ops
#define shmem_anon_vm_ops generic_file_vm_ops
#define shmem_file_operations ramfs_file_operations
-#define shmem_get_inode(idmap, sb, dir, mode, dev, flags) ramfs_get_inode(sb, dir, mode, dev)
#define shmem_acct_size(flags, size) 0
#define shmem_unacct_size(flags, size) do {} while (0)
+static inline struct inode *shmem_get_inode(struct mnt_idmap *idmap, struct super_block *sb, struct inode *dir,
+ umode_t mode, dev_t dev, unsigned long flags)
+{
+ struct inode *inode = ramfs_get_inode(sb, dir, mode, dev);
+ return inode ? inode : ERR_PTR(-ENOSPC);
+}
+
#endif /* CONFIG_SHMEM */
/* common code */
@@ -4237,9 +4262,10 @@ static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, l
inode = shmem_get_inode(&nop_mnt_idmap, mnt->mnt_sb, NULL,
S_IFREG | S_IRWXUGO, 0, flags);
- if (unlikely(!inode)) {
+
+ if (IS_ERR(inode)) {
shmem_unacct_size(flags, size);
- return ERR_PTR(-ENOSPC);
+ return ERR_CAST(inode);
}
inode->i_flags |= i_flags;
inode->i_size = size;
--
2.30.2
