[PATCH 02/10] erofs: simplify erofs_{read,fill}_inode()
From: Gao Xiang
Date: Mon Mar 10 2025 - 05:55:32 EST
- Switch to on-stack `copied` since it's just 64 bytes;
- Get rid of `nblks` and derive `i_blocks` directly;
- Use `inode_set_mtime()` instead of `inode_set_ctime()`
to follow the ondisk naming;
- Rearrange the code.
Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
---
fs/erofs/inode.c | 92 ++++++++++++++++++------------------------------
1 file changed, 35 insertions(+), 57 deletions(-)
diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 4936bd43c438..c8ede541c239 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -27,29 +27,27 @@ static int erofs_fill_symlink(struct inode *inode, void *kaddr,
static int erofs_read_inode(struct inode *inode)
{
struct super_block *sb = inode->i_sb;
+ erofs_blk_t blkaddr = erofs_blknr(sb, erofs_iloc(inode));
+ unsigned int ofs = erofs_blkoff(sb, erofs_iloc(inode));
+ struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
struct erofs_sb_info *sbi = EROFS_SB(sb);
struct erofs_inode *vi = EROFS_I(inode);
- const erofs_off_t inode_loc = erofs_iloc(inode);
- erofs_blk_t blkaddr, nblks = 0;
- void *kaddr;
+ struct erofs_inode_extended *die, copied;
struct erofs_inode_compact *dic;
- struct erofs_inode_extended *die, *copied = NULL;
union erofs_inode_i_u iu;
- struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
- unsigned int ifmt, ofs;
+ unsigned int ifmt;
+ void *ptr;
int err = 0;
- blkaddr = erofs_blknr(sb, inode_loc);
- ofs = erofs_blkoff(sb, inode_loc);
-
- kaddr = erofs_read_metabuf(&buf, sb, erofs_pos(sb, blkaddr), true);
- if (IS_ERR(kaddr)) {
- erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld",
- vi->nid, PTR_ERR(kaddr));
- return PTR_ERR(kaddr);
+ ptr = erofs_read_metabuf(&buf, sb, erofs_pos(sb, blkaddr), true);
+ if (IS_ERR(ptr)) {
+ err = PTR_ERR(ptr);
+ erofs_err(sb, "failed to get inode (nid: %llu) page, err %d",
+ vi->nid, err);
+ goto err_out;
}
- dic = kaddr + ofs;
+ dic = ptr + ofs;
ifmt = le16_to_cpu(dic->i_format);
if (ifmt & ~EROFS_I_ALL) {
erofs_err(sb, "unsupported i_format %u of nid %llu",
@@ -76,23 +74,18 @@ static int erofs_read_inode(struct inode *inode)
} else {
const unsigned int gotten = sb->s_blocksize - ofs;
- copied = kmalloc(vi->inode_isize, GFP_KERNEL);
- if (!copied) {
- err = -ENOMEM;
- goto err_out;
- }
- memcpy(copied, dic, gotten);
- kaddr = erofs_read_metabuf(&buf, sb,
+ memcpy(&copied, dic, gotten);
+ ptr = erofs_read_metabuf(&buf, sb,
erofs_pos(sb, blkaddr + 1), true);
- if (IS_ERR(kaddr)) {
- erofs_err(sb, "failed to get inode payload block (nid: %llu), err %ld",
- vi->nid, PTR_ERR(kaddr));
- kfree(copied);
- return PTR_ERR(kaddr);
+ if (IS_ERR(ptr)) {
+ err = PTR_ERR(ptr);
+ erofs_err(sb, "failed to get inode payload block (nid: %llu), err %d",
+ vi->nid, err);
+ goto err_out;
}
ofs = vi->inode_isize - gotten;
- memcpy((u8 *)copied + gotten, kaddr, ofs);
- die = copied;
+ memcpy((u8 *)&copied + gotten, ptr, ofs);
+ die = &copied;
}
vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount);
@@ -101,12 +94,10 @@ static int erofs_read_inode(struct inode *inode)
i_uid_write(inode, le32_to_cpu(die->i_uid));
i_gid_write(inode, le32_to_cpu(die->i_gid));
set_nlink(inode, le32_to_cpu(die->i_nlink));
- /* each extended inode has its own timestamp */
- inode_set_ctime(inode, le64_to_cpu(die->i_mtime),
+ inode_set_mtime(inode, le64_to_cpu(die->i_mtime),
le32_to_cpu(die->i_mtime_nsec));
inode->i_size = le64_to_cpu(die->i_size);
- kfree(copied);
break;
case EROFS_INODE_LAYOUT_COMPACT:
vi->inode_isize = sizeof(struct erofs_inode_compact);
@@ -118,8 +109,7 @@ static int erofs_read_inode(struct inode *inode)
i_uid_write(inode, le16_to_cpu(dic->i_uid));
i_gid_write(inode, le16_to_cpu(dic->i_gid));
set_nlink(inode, le16_to_cpu(dic->i_nlink));
- /* use build time for compact inodes */
- inode_set_ctime(inode, sbi->build_time, sbi->build_time_nsec);
+ inode_set_mtime(inode, sbi->build_time, sbi->build_time_nsec);
inode->i_size = le32_to_cpu(dic->i_size);
break;
@@ -141,7 +131,7 @@ static int erofs_read_inode(struct inode *inode)
case S_IFLNK:
vi->raw_blkaddr = le32_to_cpu(iu.raw_blkaddr);
if(S_ISLNK(inode->i_mode)) {
- err = erofs_fill_symlink(inode, kaddr, ofs);
+ err = erofs_fill_symlink(inode, ptr, ofs);
if (err)
goto err_out;
}
@@ -161,10 +151,13 @@ static int erofs_read_inode(struct inode *inode)
goto err_out;
}
- /* total blocks for compressed files */
- if (erofs_inode_is_data_compressed(vi->datalayout)) {
- nblks = le32_to_cpu(iu.compressed_blocks);
- } else if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {
+ if (erofs_inode_is_data_compressed(vi->datalayout))
+ inode->i_blocks = le32_to_cpu(iu.compressed_blocks) <<
+ (sb->s_blocksize_bits - 9);
+ else
+ inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9;
+
+ if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {
/* fill chunked inode summary info */
vi->chunkformat = le16_to_cpu(iu.c.format);
if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) {
@@ -176,22 +169,15 @@ static int erofs_read_inode(struct inode *inode)
vi->chunkbits = sb->s_blocksize_bits +
(vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK);
}
- inode_set_mtime_to_ts(inode,
- inode_set_atime_to_ts(inode, inode_get_ctime(inode)));
+ inode_set_atime_to_ts(inode,
+ inode_set_ctime_to_ts(inode, inode_get_mtime(inode)));
inode->i_flags &= ~S_DAX;
if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) &&
(vi->datalayout == EROFS_INODE_FLAT_PLAIN ||
vi->datalayout == EROFS_INODE_CHUNK_BASED))
inode->i_flags |= S_DAX;
-
- if (!nblks)
- /* measure inode.i_blocks as generic filesystems */
- inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9;
- else
- inode->i_blocks = nblks << (sb->s_blocksize_bits - 9);
err_out:
- DBG_BUGON(err);
erofs_put_metabuf(&buf);
return err;
}
@@ -202,13 +188,10 @@ static int erofs_fill_inode(struct inode *inode)
int err;
trace_erofs_fill_inode(inode);
-
- /* read inode base data from disk */
err = erofs_read_inode(inode);
if (err)
return err;
- /* setup the new inode */
switch (inode->i_mode & S_IFMT) {
case S_IFREG:
inode->i_op = &erofs_generic_iops;
@@ -229,15 +212,10 @@ static int erofs_fill_inode(struct inode *inode)
inode->i_op = &erofs_symlink_iops;
inode_nohighmem(inode);
break;
- case S_IFCHR:
- case S_IFBLK:
- case S_IFIFO:
- case S_IFSOCK:
+ default:
inode->i_op = &erofs_generic_iops;
init_special_inode(inode, inode->i_mode, inode->i_rdev);
return 0;
- default:
- return -EFSCORRUPTED;
}
mapping_set_large_folios(inode->i_mapping);
--
2.43.5