xfs: simplify the b_page_count calculation

Ever since we stopped using the Linux page cache to back XFS buffers
there is no need to take the start sector into account for
calculating the number of pages in a buffer, as the data always
start from the beginning of the buffer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
[dgc: modified to suit this series]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
This commit is contained in:
Christoph Hellwig 2021-06-07 11:50:00 +10:00 committed by Dave Chinner
parent 54cd3aa6f8
commit 934d1076bb

View File

@ -348,14 +348,13 @@ xfs_buf_alloc_kmem(
static int
xfs_buf_alloc_pages(
struct xfs_buf *bp,
uint page_count,
xfs_buf_flags_t flags)
{
gfp_t gfp_mask = xb_to_gfp(flags);
long filled = 0;
/* Make sure that we have a page list */
bp->b_page_count = page_count;
bp->b_page_count = DIV_ROUND_UP(BBTOB(bp->b_length), PAGE_SIZE);
if (bp->b_page_count <= XB_PAGES) {
bp->b_pages = bp->b_page_array;
} else {
@ -409,7 +408,6 @@ xfs_buf_allocate_memory(
uint flags)
{
size_t size;
xfs_off_t start, end;
int error;
/*
@ -424,11 +422,7 @@ xfs_buf_allocate_memory(
if (!error)
return 0;
}
start = BBTOB(bp->b_maps[0].bm_bn) >> PAGE_SHIFT;
end = (BBTOB(bp->b_maps[0].bm_bn + bp->b_length) + PAGE_SIZE - 1)
>> PAGE_SHIFT;
return xfs_buf_alloc_pages(bp, end - start, flags);
return xfs_buf_alloc_pages(bp, flags);
}
/*
@ -922,7 +916,6 @@ xfs_buf_get_uncached(
int flags,
struct xfs_buf **bpp)
{
unsigned long page_count;
int error;
struct xfs_buf *bp;
DEFINE_SINGLE_BUF_MAP(map, XFS_BUF_DADDR_NULL, numblks);
@ -934,8 +927,7 @@ xfs_buf_get_uncached(
if (error)
return error;
page_count = PAGE_ALIGN(numblks << BBSHIFT) >> PAGE_SHIFT;
error = xfs_buf_alloc_pages(bp, page_count, flags);
error = xfs_buf_alloc_pages(bp, flags);
if (error)
goto fail_free_buf;