erofs: avoid hardcoded blocksize for subpage block support

As the first step of converting hardcoded blocksize to that specified in
on-disk superblock, convert all call sites of hardcoded blocksize to
sb->s_blocksize except for:

1) use sbi->blkszbits instead of sb->s_blocksize in
erofs_superblock_csum_verify() since sb->s_blocksize has not been
updated with the on-disk blocksize yet when the function is called.

2) use inode->i_blkbits instead of sb->s_blocksize in erofs_bread(),
since the inode operated on may be an anonymous inode in fscache mode.
Currently the anonymous inode is allocated from an anonymous mount
maintained in erofs, while in the near future we may allocate anonymous
inodes from a generic API directly and thus have no access to the
anonymous inode's i_sb.  Thus we keep the block size in i_blkbits for
anonymous inodes in fscache mode.

Be noted that this patch only gets rid of the hardcoded blocksize, in
preparation for actually setting the on-disk block size in the following
patch.  The hard limit of constraining the block size to PAGE_SIZE still
exists until the next patch.

Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20230313135309.75269-2-jefflexu@linux.alibaba.com
[ Gao Xiang: fold a patch to fix incorrect truncated offsets. ]
Link: https://lore.kernel.org/r/20230413035734.15457-1-zhujia.zj@bytedance.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

1 files changed, 19 insertions, 21 deletions

diff --git a/fs/erofs/xattr.c b/fs/erofs/xattr.c
index 60729b1220b6..459caa3cd65d 100644
--- a/fs/erofs/xattr.c
+++ b/fs/erofs/xattr.c
@@ -68,8 +68,8 @@ static int init_inode_xattrs(struct inode *inode)
 	}
 
 	it.buf = __EROFS_BUF_INITIALIZER;
-	it.blkaddr = erofs_blknr(erofs_iloc(inode) + vi->inode_isize);
-	it.ofs = erofs_blkoff(erofs_iloc(inode) + vi->inode_isize);
+	it.blkaddr = erofs_blknr(sb, erofs_iloc(inode) + vi->inode_isize);
+	it.ofs = erofs_blkoff(sb, erofs_iloc(inode) + vi->inode_isize);
 
 	/* read in shared xattr array (non-atomic, see kmalloc below) */
 	it.kaddr = erofs_read_metabuf(&it.buf, sb, it.blkaddr, EROFS_KMAP);
@@ -92,9 +92,9 @@ static int init_inode_xattrs(struct inode *inode)
 	it.ofs += sizeof(struct erofs_xattr_ibody_header);
 
 	for (i = 0; i < vi->xattr_shared_count; ++i) {
-		if (it.ofs >= EROFS_BLKSIZ) {
+		if (it.ofs >= sb->s_blocksize) {
 			/* cannot be unaligned */
-			DBG_BUGON(it.ofs != EROFS_BLKSIZ);
+			DBG_BUGON(it.ofs != sb->s_blocksize);
 
 			it.kaddr = erofs_read_metabuf(&it.buf, sb, ++it.blkaddr,
 						      EROFS_KMAP);
@@ -139,15 +139,15 @@ struct xattr_iter_handlers {
 
 static inline int xattr_iter_fixup(struct xattr_iter *it)
 {
-	if (it->ofs < EROFS_BLKSIZ)
+	if (it->ofs < it->sb->s_blocksize)
 		return 0;
 
-	it->blkaddr += erofs_blknr(it->ofs);
+	it->blkaddr += erofs_blknr(it->sb, it->ofs);
 	it->kaddr = erofs_read_metabuf(&it->buf, it->sb, it->blkaddr,
 				       EROFS_KMAP);
 	if (IS_ERR(it->kaddr))
 		return PTR_ERR(it->kaddr);
-	it->ofs = erofs_blkoff(it->ofs);
+	it->ofs = erofs_blkoff(it->sb, it->ofs);
 	return 0;
 }
 
@@ -165,8 +165,8 @@ static int inline_xattr_iter_begin(struct xattr_iter *it,
 
 	inline_xattr_ofs = vi->inode_isize + xattr_header_sz;
 
-	it->blkaddr = erofs_blknr(erofs_iloc(inode) + inline_xattr_ofs);
-	it->ofs = erofs_blkoff(erofs_iloc(inode) + inline_xattr_ofs);
+	it->blkaddr = erofs_blknr(it->sb, erofs_iloc(inode) + inline_xattr_ofs);
+	it->ofs = erofs_blkoff(it->sb, erofs_iloc(inode) + inline_xattr_ofs);
 	it->kaddr = erofs_read_metabuf(&it->buf, inode->i_sb, it->blkaddr,
 				       EROFS_KMAP);
 	if (IS_ERR(it->kaddr))
@@ -222,8 +222,8 @@ static int xattr_foreach(struct xattr_iter *it,
 	processed = 0;
 
 	while (processed < entry.e_name_len) {
-		if (it->ofs >= EROFS_BLKSIZ) {
-			DBG_BUGON(it->ofs > EROFS_BLKSIZ);
+		if (it->ofs >= it->sb->s_blocksize) {
+			DBG_BUGON(it->ofs > it->sb->s_blocksize);
 
 			err = xattr_iter_fixup(it);
 			if (err)
@@ -231,7 +231,7 @@ static int xattr_foreach(struct xattr_iter *it,
 			it->ofs = 0;
 		}
 
-		slice = min_t(unsigned int, EROFS_BLKSIZ - it->ofs,
+		slice = min_t(unsigned int, it->sb->s_blocksize - it->ofs,
 			      entry.e_name_len - processed);
 
 		/* handle name */
@@ -257,8 +257,8 @@ static int xattr_foreach(struct xattr_iter *it,
 	}
 
 	while (processed < value_sz) {
-		if (it->ofs >= EROFS_BLKSIZ) {
-			DBG_BUGON(it->ofs > EROFS_BLKSIZ);
+		if (it->ofs >= it->sb->s_blocksize) {
+			DBG_BUGON(it->ofs > it->sb->s_blocksize);
 
 			err = xattr_iter_fixup(it);
 			if (err)
@@ -266,7 +266,7 @@ static int xattr_foreach(struct xattr_iter *it,
 			it->ofs = 0;
 		}
 
-		slice = min_t(unsigned int, EROFS_BLKSIZ - it->ofs,
+		slice = min_t(unsigned int, it->sb->s_blocksize - it->ofs,
 			      value_sz - processed);
 		op->value(it, processed, it->kaddr + it->ofs, slice);
 		it->ofs += slice;
@@ -352,15 +352,14 @@ static int shared_getxattr(struct inode *inode, struct getxattr_iter *it)
 {
 	struct erofs_inode *const vi = EROFS_I(inode);
 	struct super_block *const sb = inode->i_sb;
-	struct erofs_sb_info *const sbi = EROFS_SB(sb);
 	unsigned int i;
 	int ret = -ENOATTR;
 
 	for (i = 0; i < vi->xattr_shared_count; ++i) {
 		erofs_blk_t blkaddr =
-			xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]);
+			xattrblock_addr(sb, vi->xattr_shared_xattrs[i]);
 
-		it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]);
+		it->it.ofs = xattrblock_offset(sb, vi->xattr_shared_xattrs[i]);
 		it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, blkaddr,
 						  EROFS_KMAP);
 		if (IS_ERR(it->it.kaddr))
@@ -564,15 +563,14 @@ static int shared_listxattr(struct listxattr_iter *it)
 	struct inode *const inode = d_inode(it->dentry);
 	struct erofs_inode *const vi = EROFS_I(inode);
 	struct super_block *const sb = inode->i_sb;
-	struct erofs_sb_info *const sbi = EROFS_SB(sb);
 	unsigned int i;
 	int ret = 0;
 
 	for (i = 0; i < vi->xattr_shared_count; ++i) {
 		erofs_blk_t blkaddr =
-			xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]);
+			xattrblock_addr(sb, vi->xattr_shared_xattrs[i]);
 
-		it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]);
+		it->it.ofs = xattrblock_offset(sb, vi->xattr_shared_xattrs[i]);
 		it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, blkaddr,
 						  EROFS_KMAP);
 		if (IS_ERR(it->it.kaddr))