The patch titled
Subject: mm/filemap: fix readahead return types
has been added to the -mm tree. Its filename is
mm-filemap-fix-readahead-return-types.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-filemap-fix-readahead-return-types.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-filemap-fix-readahead-return-types.patch
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The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm/filemap: fix readahead return types
A readahead request will not allocate more memory than can be represented
by a size_t, even on systems that have HIGHMEM available. Change the
length functions from returning an loff_t to a size_t.
Link: https://lkml.kernel.org/r/20210510201201.1558972-1-willy@xxxxxxxxxxxxx
Fixes: 32c0a6bcaa1f57 ("btrfs: add and use readahead_batch_length")
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/iomap/buffered-io.c | 4 ++--
include/linux/pagemap.h | 6 +++---
2 files changed, 5 insertions(+), 5 deletions(-)
--- a/fs/iomap/buffered-io.c~mm-filemap-fix-readahead-return-types
+++ a/fs/iomap/buffered-io.c
@@ -394,7 +394,7 @@ void iomap_readahead(struct readahead_co
{
struct inode *inode = rac->mapping->host;
loff_t pos = readahead_pos(rac);
- loff_t length = readahead_length(rac);
+ size_t length = readahead_length(rac);
struct iomap_readpage_ctx ctx = {
.rac = rac,
};
@@ -402,7 +402,7 @@ void iomap_readahead(struct readahead_co
trace_iomap_readahead(inode, readahead_count(rac));
while (length > 0) {
- loff_t ret = iomap_apply(inode, pos, length, 0, ops,
+ ssize_t ret = iomap_apply(inode, pos, length, 0, ops,
&ctx, iomap_readahead_actor);
if (ret <= 0) {
WARN_ON_ONCE(ret == 0);
--- a/include/linux/pagemap.h~mm-filemap-fix-readahead-return-types
+++ a/include/linux/pagemap.h
@@ -997,9 +997,9 @@ static inline loff_t readahead_pos(struc
* readahead_length - The number of bytes in this readahead request.
* @rac: The readahead request.
*/
-static inline loff_t readahead_length(struct readahead_control *rac)
+static inline size_t readahead_length(struct readahead_control *rac)
{
- return (loff_t)rac->_nr_pages * PAGE_SIZE;
+ return rac->_nr_pages * PAGE_SIZE;
}
/**
@@ -1024,7 +1024,7 @@ static inline unsigned int readahead_cou
* readahead_batch_length - The number of bytes in the current batch.
* @rac: The readahead request.
*/
-static inline loff_t readahead_batch_length(struct readahead_control *rac)
+static inline size_t readahead_batch_length(struct readahead_control *rac)
{
return rac->_batch_count * PAGE_SIZE;
}
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-fix-struct-page-layout-on-32-bit-systems.patch
mm-filemap-fix-readahead-return-types.patch
mm-make-__dump_page-static.patch
mm-debug-factor-pagepoisoned-out-of-__dump_page.patch
mm-page_owner-constify-dump_page_owner.patch
mm-make-compound_head-const-preserving.patch
mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype.patch
mm-constify-page_count-and-page_ref_count.patch
mm-optimise-nth_page-for-contiguous-memmap.patch
