@@ -127,50 +127,39 @@ static int read_inode(struct inode *inode, void *data)
return -EFSCORRUPTED;
}
-/*
- * try_lock can be required since locking order is:
- * file data(fs_inode)
- * meta(bd_inode)
- * but the majority of the callers is "iget",
- * in that case we are pretty sure no deadlock since
- * no data operations exist. However I tend to
- * try_lock since it takes no much overhead and
- * will success immediately.
- */
-static int fill_inline_data(struct inode *inode, void *data,
- unsigned int m_pofs)
+static int erofs_fill_symlink(struct inode *inode, void *data,
+ unsigned int m_pofs)
{
struct erofs_inode *vi = EROFS_I(inode);
struct erofs_sb_info *sbi = EROFS_I_SB(inode);
+ char *lnk;
- /* should be tail-packing data inline */
- if (vi->datalayout != EROFS_INODE_FLAT_INLINE)
+ /* if it cannot be handled with fast symlink scheme */
+ if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
+ inode->i_size >= PAGE_SIZE) {
+ inode->i_op = &erofs_symlink_iops;
return 0;
+ }
- /* fast symlink */
- if (S_ISLNK(inode->i_mode) && inode->i_size < PAGE_SIZE) {
- char *lnk = erofs_kmalloc(sbi, inode->i_size + 1, GFP_KERNEL);
-
- if (!lnk)
- return -ENOMEM;
-
- m_pofs += vi->inode_isize + vi->xattr_isize;
+ lnk = erofs_kmalloc(sbi, inode->i_size + 1, GFP_KERNEL);
+ if (!lnk)
+ return -ENOMEM;
- /* inline symlink data shouldn't cross page boundary as well */
- if (m_pofs + inode->i_size > PAGE_SIZE) {
- kfree(lnk);
- errln("inline data cross block boundary @ nid %llu",
- vi->nid);
- DBG_BUGON(1);
- return -EFSCORRUPTED;
- }
+ m_pofs += vi->inode_isize + vi->xattr_isize;
+ /* inline symlink data shouldn't cross page boundary as well */
+ if (m_pofs + inode->i_size > PAGE_SIZE) {
+ kfree(lnk);
+ errln("inline data cross block boundary @ nid %llu",
+ vi->nid);
+ DBG_BUGON(1);
+ return -EFSCORRUPTED;
+ }
- memcpy(lnk, data + m_pofs, inode->i_size);
- lnk[inode->i_size] = '\0';
+ memcpy(lnk, data + m_pofs, inode->i_size);
+ lnk[inode->i_size] = '\0';
- inode->i_link = lnk;
- set_inode_fast_symlink(inode);
- }
+ inode->i_link = lnk;
+ inode->i_op = &erofs_fast_symlink_iops;
return 0;
}
@@ -217,8 +206,9 @@ static int fill_inode(struct inode *inode, int isdir)
inode->i_fop = &erofs_dir_fops;
break;
case S_IFLNK:
- /* by default, page_get_link is used for symlink */
- inode->i_op = &erofs_symlink_iops;
+ err = erofs_fill_symlink(inode, data, ofs);
+ if (err)
+ goto out_unlock;
inode_nohighmem(inode);
break;
case S_IFCHR:
@@ -237,11 +227,7 @@ static int fill_inode(struct inode *inode, int isdir)
err = z_erofs_fill_inode(inode);
goto out_unlock;
}
-
inode->i_mapping->a_ops = &erofs_raw_access_aops;
-
- /* fill last page if inline data is available */
- err = fill_inline_data(inode, data, ofs);
}
out_unlock:
@@ -479,16 +479,6 @@ extern const struct inode_operations erofs_generic_iops;
extern const struct inode_operations erofs_symlink_iops;
extern const struct inode_operations erofs_fast_symlink_iops;
-static inline void set_inode_fast_symlink(struct inode *inode)
-{
- inode->i_op = &erofs_fast_symlink_iops;
-}
-
-static inline bool is_inode_fast_symlink(struct inode *inode)
-{
- return inode->i_op == &erofs_fast_symlink_iops;
-}
-
struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid, bool dir);
int erofs_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags);
@@ -40,10 +40,9 @@ static void free_inode(struct inode *inode)
{
struct erofs_inode *vi = EROFS_I(inode);
- /* be careful RCU symlink path (see ext4_inode_info->i_data)! */
- if (is_inode_fast_symlink(inode))
+ /* be careful of RCU symlink path */
+ if (inode->i_op == &erofs_fast_symlink_iops)
kfree(inode->i_link);
-
kfree(vi->xattr_shared_xattrs);
kmem_cache_free(erofs_inode_cachep, vi);
Fix as Christoph suggested [1] [2], "remove is_inode_fast_symlink and just opencode it in the few places using it" and "Please just set the ops directly instead of obsfucating that in a single caller, single line inline function. And please set it instead of the normal symlink iops in the same place where you also set those." [1] https://lore.kernel.org/r/20190830163910.GB29603@infradead.org/ [2] https://lore.kernel.org/r/20190829102426.GE20598@infradead.org/ Reported-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com> --- fs/erofs/inode.c | 68 ++++++++++++++++++--------------------------- fs/erofs/internal.h | 10 ------- fs/erofs/super.c | 5 ++-- 3 files changed, 29 insertions(+), 54 deletions(-)