[PATCH 1/2] ocfs2: Use memcpy_to_folio() in ocfs2_symlink_get_block()

[PATCH 1/2] ocfs2: Use memcpy_to_folio() in ocfs2_symlink_get_block()

[Matthew Wilcox (Oracle)]

Replace use of kmap_atomic() with the higher-level construct
memcpy_to_folio().  This removes a use of b_page and supports
large folios as well as being easier to understand.  It also
removes the check for kmap_atomic() failing (because it can't).

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 fs/ocfs2/aops.c | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 5bbeb6fbb1ac..ccf2930cd2e6 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -46,7 +46,6 @@ static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock,
 	struct buffer_head *bh = NULL;
 	struct buffer_head *buffer_cache_bh = NULL;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
-	void *kaddr;
 
 	trace_ocfs2_symlink_get_block(
 			(unsigned long long)OCFS2_I(inode)->ip_blkno,
@@ -91,17 +90,11 @@ static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock,
 		 * could've happened. Since we've got a reference on
 		 * the bh, even if it commits while we're doing the
 		 * copy, the data is still good. */
-		if (buffer_jbd(buffer_cache_bh)
-		    && ocfs2_inode_is_new(inode)) {
-			kaddr = kmap_atomic(bh_result->b_page);
-			if (!kaddr) {
-				mlog(ML_ERROR, "couldn't kmap!\n");
-				goto bail;
-			}
-			memcpy(kaddr + (bh_result->b_size * iblock),
-			       buffer_cache_bh->b_data,
-			       bh_result->b_size);
-			kunmap_atomic(kaddr);
+		if (buffer_jbd(buffer_cache_bh) && ocfs2_inode_is_new(inode)) {
+			memcpy_to_folio(bh_result->b_folio,
+					bh_result->b_size * iblock,
+					buffer_cache_bh->b_data,
+					bh_result->b_size);
 			set_buffer_uptodate(bh_result);
 		}
 		brelse(buffer_cache_bh);
-- 
2.47.2

[PATCH 2/2] ocfs2: Remove reference to bh->b_page

[Matthew Wilcox (Oracle)]

Buffer heads are attached to folios, not to pages.  Also
flush_dcache_page() is now deprecated in favour of flush_dcache_folio().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 fs/ocfs2/quota_global.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c
index 15d9acd456ec..e85b1ccf81be 100644
--- a/fs/ocfs2/quota_global.c
+++ b/fs/ocfs2/quota_global.c
@@ -273,7 +273,7 @@ ssize_t ocfs2_quota_write(struct super_block *sb, int type,
 	if (new)
 		memset(bh->b_data, 0, sb->s_blocksize);
 	memcpy(bh->b_data + offset, data, len);
-	flush_dcache_page(bh->b_page);
+	flush_dcache_folio(bh->b_folio);
 	set_buffer_uptodate(bh);
 	unlock_buffer(bh);
 	ocfs2_set_buffer_uptodate(INODE_CACHE(gqinode), bh);
-- 
2.47.2

Re: [PATCH 1/2] ocfs2: Use memcpy_to_folio() in ocfs2_symlink_get_block()

[Joseph Qi]

On 2025/2/14 05:45, Matthew Wilcox (Oracle) wrote:
> Replace use of kmap_atomic() with the higher-level construct
> memcpy_to_folio().  This removes a use of b_page and supports
> large folios as well as being easier to understand.  It also
> removes the check for kmap_atomic() failing (because it can't).
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
> ---
>  fs/ocfs2/aops.c | 17 +++++------------
>  1 file changed, 5 insertions(+), 12 deletions(-)
> 
> diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
> index 5bbeb6fbb1ac..ccf2930cd2e6 100644
> --- a/fs/ocfs2/aops.c
> +++ b/fs/ocfs2/aops.c
> @@ -46,7 +46,6 @@ static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock,
>  	struct buffer_head *bh = NULL;
>  	struct buffer_head *buffer_cache_bh = NULL;
>  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
> -	void *kaddr;
>  
>  	trace_ocfs2_symlink_get_block(
>  			(unsigned long long)OCFS2_I(inode)->ip_blkno,
> @@ -91,17 +90,11 @@ static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock,
>  		 * could've happened. Since we've got a reference on
>  		 * the bh, even if it commits while we're doing the
>  		 * copy, the data is still good. */
> -		if (buffer_jbd(buffer_cache_bh)
> -		    && ocfs2_inode_is_new(inode)) {
> -			kaddr = kmap_atomic(bh_result->b_page);
> -			if (!kaddr) {
> -				mlog(ML_ERROR, "couldn't kmap!\n");
> -				goto bail;
> -			}
> -			memcpy(kaddr + (bh_result->b_size * iblock),
> -			       buffer_cache_bh->b_data,
> -			       bh_result->b_size);
> -			kunmap_atomic(kaddr);
> +		if (buffer_jbd(buffer_cache_bh) && ocfs2_inode_is_new(inode)) {
> +			memcpy_to_folio(bh_result->b_folio,
> +					bh_result->b_size * iblock,
> +					buffer_cache_bh->b_data,
> +					bh_result->b_size);
>  			set_buffer_uptodate(bh_result);
>  		}
>  		brelse(buffer_cache_bh);

Re: [PATCH 2/2] ocfs2: Remove reference to bh->b_page

[Joseph Qi]

On 2025/2/14 05:45, Matthew Wilcox (Oracle) wrote:
> Buffer heads are attached to folios, not to pages.  Also
> flush_dcache_page() is now deprecated in favour of flush_dcache_folio().
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
> ---
>  fs/ocfs2/quota_global.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c
> index 15d9acd456ec..e85b1ccf81be 100644
> --- a/fs/ocfs2/quota_global.c
> +++ b/fs/ocfs2/quota_global.c
> @@ -273,7 +273,7 @@ ssize_t ocfs2_quota_write(struct super_block *sb, int type,
>  	if (new)
>  		memset(bh->b_data, 0, sb->s_blocksize);
>  	memcpy(bh->b_data + offset, data, len);
> -	flush_dcache_page(bh->b_page);
> +	flush_dcache_folio(bh->b_folio);
>  	set_buffer_uptodate(bh);
>  	unlock_buffer(bh);
>  	ocfs2_set_buffer_uptodate(INODE_CACHE(gqinode), bh);