Factor out two helpers that do everything needed for allocating and
freeing pages that back a buffer, and remove the duplication between
the different interfaces.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/xfs/xfs_buf.c | 110 ++++++++++++++++-------------------------------
1 file changed, 37 insertions(+), 73 deletions(-)
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 76a107e3cb2a22..31aff8323605cd 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -273,35 +273,17 @@ _xfs_buf_alloc(
}
/*
- * Allocate a page array capable of holding a specified number
- * of pages, and point the page buf at it.
+ * Free all pages allocated to the buffer including the page map.
*/
-STATIC int
-_xfs_buf_get_pages(
- struct xfs_buf *bp)
+static void
+xfs_buf_free_pages(
+ struct xfs_buf *bp)
{
- ASSERT(bp->b_pages == NULL);
-
- bp->b_page_count = DIV_ROUND_UP(BBTOB(bp->b_length), PAGE_SIZE);
- if (bp->b_page_count > XB_PAGES) {
- bp->b_pages = kmem_zalloc(sizeof(struct page *) *
- bp->b_page_count, KM_NOFS);
- if (!bp->b_pages)
- return -ENOMEM;
- } else {
- bp->b_pages = bp->b_page_array;
- }
+ unsigned int i;
- return 0;
-}
+ for (i = 0; i < bp->b_page_count; i++)
+ __free_page(bp->b_pages[i]);
-/*
- * Frees b_pages if it was allocated.
- */
-STATIC void
-_xfs_buf_free_pages(
- struct xfs_buf *bp)
-{
if (bp->b_pages != bp->b_page_array) {
kmem_free(bp->b_pages);
bp->b_pages = NULL;
@@ -324,22 +306,14 @@ xfs_buf_free(
ASSERT(list_empty(&bp->b_lru));
if (bp->b_flags & _XBF_PAGES) {
- uint i;
-
if (xfs_buf_is_vmapped(bp))
vm_unmap_ram(bp->b_addr, bp->b_page_count);
-
- for (i = 0; i < bp->b_page_count; i++) {
- struct page *page = bp->b_pages[i];
-
- __free_page(page);
- }
+ xfs_buf_free_pages(bp);
if (current->reclaim_state)
current->reclaim_state->reclaimed_slab +=
bp->b_page_count;
} else if (bp->b_flags & _XBF_KMEM)
kmem_free(bp->b_addr);
- _xfs_buf_free_pages(bp);
xfs_buf_free_maps(bp);
kmem_cache_free(xfs_buf_zone, bp);
}
@@ -380,34 +354,33 @@ xfs_buf_alloc_slab(
static int
xfs_buf_alloc_pages(
struct xfs_buf *bp,
- uint flags)
+ gfp_t gfp_mask,
+ bool fail_fast)
{
- gfp_t gfp_mask = xb_to_gfp(flags);
- unsigned short i;
- int error;
-
- /*
- * assure zeroed buffer for non-read cases.
- */
- if (!(flags & XBF_READ))
- gfp_mask |= __GFP_ZERO;
+ int i;
- error = _xfs_buf_get_pages(bp);
- if (unlikely(error))
- return error;
+ ASSERT(bp->b_pages == NULL);
- bp->b_flags |= _XBF_PAGES;
+ bp->b_page_count = DIV_ROUND_UP(BBTOB(bp->b_length), PAGE_SIZE);
+ if (bp->b_page_count > XB_PAGES) {
+ bp->b_pages = kmem_zalloc(sizeof(struct page *) *
+ bp->b_page_count, KM_NOFS);
+ if (!bp->b_pages)
+ return -ENOMEM;
+ } else {
+ bp->b_pages = bp->b_page_array;
+ }
for (i = 0; i < bp->b_page_count; i++) {
struct page *page;
uint retries = 0;
retry:
page = alloc_page(gfp_mask);
- if (unlikely(page == NULL)) {
- if (flags & XBF_READ_AHEAD) {
+ if (unlikely(!page)) {
+ if (fail_fast) {
bp->b_page_count = i;
- error = -ENOMEM;
- goto out_free_pages;
+ xfs_buf_free_pages(bp);
+ return -ENOMEM;
}
/*
@@ -429,13 +402,9 @@ xfs_buf_alloc_pages(
bp->b_pages[i] = page;
}
- return 0;
-out_free_pages:
- for (i = 0; i < bp->b_page_count; i++)
- __free_page(bp->b_pages[i]);
- bp->b_flags &= ~_XBF_PAGES;
- return error;
+ bp->b_flags |= _XBF_PAGES;
+ return 0;
}
/*
@@ -706,7 +675,13 @@ xfs_buf_get_map(
*/
if (BBTOB(new_bp->b_length) >= PAGE_SIZE ||
xfs_buf_alloc_slab(new_bp, flags) < 0) {
- error = xfs_buf_alloc_pages(new_bp, flags);
+ gfp_t gfp_mask = xb_to_gfp(flags);
+
+ /* assure a zeroed buffer for non-read cases */
+ if (!(flags & XBF_READ))
+ gfp_mask |= __GFP_ZERO;
+ error = xfs_buf_alloc_pages(new_bp, gfp_mask,
+ flags & XBF_READ_AHEAD);
if (error)
goto out_free_buf;
}
@@ -936,7 +911,7 @@ xfs_buf_get_uncached(
int flags,
struct xfs_buf **bpp)
{
- int error, i;
+ int error;
struct xfs_buf *bp;
DEFINE_SINGLE_BUF_MAP(map, XFS_BUF_DADDR_NULL, numblks);
@@ -947,19 +922,10 @@ xfs_buf_get_uncached(
if (error)
goto fail;
- error = _xfs_buf_get_pages(bp);
+ error = xfs_buf_alloc_pages(bp, xb_to_gfp(flags), true);
if (error)
goto fail_free_buf;
- for (i = 0; i < bp->b_page_count; i++) {
- bp->b_pages[i] = alloc_page(xb_to_gfp(flags));
- if (!bp->b_pages[i]) {
- error = -ENOMEM;
- goto fail_free_mem;
- }
- }
- bp->b_flags |= _XBF_PAGES;
-
error = _xfs_buf_map_pages(bp, 0);
if (unlikely(error)) {
xfs_warn(target->bt_mount,
@@ -972,9 +938,7 @@ xfs_buf_get_uncached(
return 0;
fail_free_mem:
- while (--i >= 0)
- __free_page(bp->b_pages[i]);
- _xfs_buf_free_pages(bp);
+ xfs_buf_free_pages(bp);
fail_free_buf:
xfs_buf_free_maps(bp);
kmem_cache_free(xfs_buf_zone, bp);
--
2.30.2
