After commit a65917156e34594 ("Btrfs: stop using highmem for
extent_buffers") we don't need to call kmap_atomic anymore and can
reduce the move_pages helper to a simple memmove.There's only one caller of memcpy_extent_buffer, we can use the memmove_ variant here. Signed-off-by: David Sterba <[email protected]> --- fs/btrfs/ctree.c | 2 +- fs/btrfs/extent_io.c | 88 +------------------------------------------------ 2 files changed, 3 insertions(+), 87 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 566d99b..154573e 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -4270,7 +4270,7 @@ int btrfs_duplicate_item(struct btrfs_trans_handle *trans, item_size, item_size + sizeof(struct btrfs_item), 1); leaf = path->nodes[0]; - memcpy_extent_buffer(leaf, + memmove_extent_buffer(leaf, btrfs_item_ptr_offset(leaf, path->slots[0]), btrfs_item_ptr_offset(leaf, path->slots[0] - 1), item_size); diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index dbb2bde..e1abebd 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4943,89 +4943,9 @@ static void move_pages(struct page *dst_page, struct page *src_page, unsigned long len) { char *dst_kaddr = page_address(dst_page); - if (dst_page == src_page) { - memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); - } else { - char *src_kaddr = page_address(src_page); - char *p = dst_kaddr + dst_off + len; - char *s = src_kaddr + src_off + len; + char *src_kaddr = page_address(src_page); - while (len--) - *--p = *--s; - } -} - -static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len) -{ - unsigned long distance = (src > dst) ? src - dst : dst - src; - return distance < len; -} - -static void copy_pages(struct page *dst_page, struct page *src_page, - unsigned long dst_off, unsigned long src_off, - unsigned long len) -{ - char *dst_kaddr = page_address(dst_page); - char *src_kaddr; - int must_memmove = 0; - - if (dst_page != src_page) { - src_kaddr = page_address(src_page); - } else { - src_kaddr = dst_kaddr; - if (areas_overlap(src_off, dst_off, len)) - must_memmove = 1; - } - - if (must_memmove) - memmove(dst_kaddr + dst_off, src_kaddr + src_off, len); - else - memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); -} - -void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, - unsigned long src_offset, unsigned long len) -{ - size_t cur; - size_t dst_off_in_page; - size_t src_off_in_page; - size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); - unsigned long dst_i; - unsigned long src_i; - - if (src_offset + len > dst->len) { - printk(KERN_ERR "btrfs memmove bogus src_offset %lu move " - "len %lu dst len %lu\n", src_offset, len, dst->len); - BUG_ON(1); - } - if (dst_offset + len > dst->len) { - printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move " - "len %lu dst len %lu\n", dst_offset, len, dst->len); - BUG_ON(1); - } - - while (len > 0) { - dst_off_in_page = (start_offset + dst_offset) & - ((unsigned long)PAGE_CACHE_SIZE - 1); - src_off_in_page = (start_offset + src_offset) & - ((unsigned long)PAGE_CACHE_SIZE - 1); - - dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; - src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; - - cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - - src_off_in_page)); - cur = min_t(unsigned long, cur, - (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); - - copy_pages(extent_buffer_page(dst, dst_i), - extent_buffer_page(dst, src_i), - dst_off_in_page, src_off_in_page, cur); - - src_offset += cur; - dst_offset += cur; - len -= cur; - } + memmove(dst_kaddr + dst_off, src_kaddr + src_off, len); } void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, @@ -5050,10 +4970,6 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, "len %lu len %lu\n", dst_offset, len, dst->len); BUG_ON(1); } - if (dst_offset < src_offset) { - memcpy_extent_buffer(dst, dst_offset, src_offset, len); - return; - } while (len > 0) { dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; -- 1.7.9 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
