Commit 59d169e2 authored by Chris Mason's avatar Chris Mason
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Btrfs: Fix read/write_extent_buffer to use KM_USER1 instead of KM_USER0 



This avoids recursive use of KM_USER0 during btrfs_file_write

Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent b4a2a0ed

fs/btrfs/extent_map.c

+4 −4
Original line number Diff line number Diff line
@@ -2378,9 +2378,9 @@ void read_extent_buffer(struct extent_buffer *eb, void *dstv, 
		WARN_ON(!PageUptodate(page));



		cur = min(len, (PAGE_CACHE_SIZE - offset));

		kaddr = kmap_atomic(page, KM_USER0);

		kaddr = kmap_atomic(page, KM_USER1);

		memcpy(dst, kaddr + offset, cur);

		kunmap_atomic(kaddr, KM_USER0);

		kunmap_atomic(kaddr, KM_USER1);



		dst += cur;

		len -= cur;
@@ -2523,9 +2523,9 @@ void write_extent_buffer(struct extent_buffer *eb, const void *srcv, 
		WARN_ON(!PageUptodate(page));



		cur = min(len, PAGE_CACHE_SIZE - offset);

		kaddr = kmap_atomic(page, KM_USER0);

		kaddr = kmap_atomic(page, KM_USER1);

		memcpy(kaddr + offset, src, cur);

		kunmap_atomic(kaddr, KM_USER0);

		kunmap_atomic(kaddr, KM_USER1);



		src += cur;

		len -= cur;