The patch titled
Subject: buffer: add kernel-doc for brelse() and __brelse()
has been added to the -mm mm-unstable branch. Its filename is
buffer-add-kernel-doc-for-brelse-and-__brelse.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/buffer-add-kernel-doc-for-brelse-and-__brelse.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: buffer: add kernel-doc for brelse() and __brelse()
Date: Tue, 16 Apr 2024 04:17:49 +0100
Move the documentation for __brelse() to brelse(), format it as kernel-doc
and update it from talking about pages to folios.
Link: https://lkml.kernel.org/r/20240416031754.4076917-6-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/buffer.c | 17 ++++++++---------
include/linux/buffer_head.h | 16 ++++++++++++++++
2 files changed, 24 insertions(+), 9 deletions(-)
--- a/fs/buffer.c~buffer-add-kernel-doc-for-brelse-and-__brelse
+++ a/fs/buffer.c
@@ -1226,17 +1226,16 @@ void mark_buffer_write_io_error(struct b
}
EXPORT_SYMBOL(mark_buffer_write_io_error);
-/*
- * Decrement a buffer_head's reference count. If all buffers against a page
- * have zero reference count, are clean and unlocked, and if the page is clean
- * and unlocked then try_to_free_buffers() may strip the buffers from the page
- * in preparation for freeing it (sometimes, rarely, buffers are removed from
- * a page but it ends up not being freed, and buffers may later be reattached).
+/**
+ * __brelse - Release a buffer.
+ * @bh: The buffer to release.
+ *
+ * This variant of brelse() can be called if @bh is guaranteed to not be NULL.
*/
-void __brelse(struct buffer_head * buf)
+void __brelse(struct buffer_head *bh)
{
- if (atomic_read(&buf->b_count)) {
- put_bh(buf);
+ if (atomic_read(&bh->b_count)) {
+ put_bh(bh);
return;
}
WARN(1, KERN_ERR "VFS: brelse: Trying to free free buffer\n");
--- a/include/linux/buffer_head.h~buffer-add-kernel-doc-for-brelse-and-__brelse
+++ a/include/linux/buffer_head.h
@@ -303,6 +303,22 @@ static inline void put_bh(struct buffer_
atomic_dec(&bh->b_count);
}
+/**
+ * brelse - Release a buffer.
+ * @bh: The buffer to release.
+ *
+ * Decrement a buffer_head's reference count. If @bh is NULL, this
+ * function is a no-op.
+ *
+ * If all buffers on a folio have zero reference count, are clean
+ * and unlocked, and if the folio is unlocked and not under writeback
+ * then try_to_free_buffers() may strip the buffers from the folio in
+ * preparation for freeing it (sometimes, rarely, buffers are removed
+ * from a folio but it ends up not being freed, and buffers may later
+ * be reattached).
+ *
+ * Context: Any context.
+ */
static inline void brelse(struct buffer_head *bh)
{
if (bh)
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-always-initialise-folio-_deferred_list.patch
mm-create-folio_flag_false-and-folio_type_ops-macros.patch
mm-remove-folio_prep_large_rmappable.patch
mm-support-page_mapcount-on-page_has_type-pages.patch
mm-turn-folio_test_hugetlb-into-a-pagetype.patch
mm-turn-folio_test_hugetlb-into-a-pagetype-fix.patch
mm-remove-a-call-to-compound_head-from-is_page_hwpoison.patch
mm-free-up-pg_slab.patch
mm-free-up-pg_slab-fix.patch
mm-improve-dumping-of-mapcount-and-page_type.patch
hugetlb-remove-mention-of-destructors.patch
sh-remove-use-of-pg_arch_1-on-individual-pages.patch
xtensa-remove-uses-of-pg_arch_1-on-individual-pages.patch
mm-make-page_ext_get-take-a-const-argument.patch
mm-make-folio_test_idle-and-folio_test_young-take-a-const-argument.patch
mm-make-is_free_buddy_page-take-a-const-argument.patch
mm-make-page_mapped-take-a-const-argument.patch
mm-convert-arch_clear_hugepage_flags-to-take-a-folio.patch
mm-convert-arch_clear_hugepage_flags-to-take-a-folio-fix.patch
slub-remove-use-of-page-flags.patch
remove-references-to-page-flags-in-documentation.patch
proc-rewrite-stable_page_flags.patch
proc-rewrite-stable_page_flags-fix.patch
proc-rewrite-stable_page_flags-fix-2.patch
sparc-use-is_huge_zero_pmd.patch
mm-add-is_huge_zero_folio.patch
mm-add-pmd_folio.patch
mm-convert-migrate_vma_collect_pmd-to-use-a-folio.patch
mm-convert-huge_zero_page-to-huge_zero_folio.patch
mm-convert-do_huge_pmd_anonymous_page-to-huge_zero_folio.patch
dax-use-huge_zero_folio.patch
mm-rename-mm_put_huge_zero_page-to-mm_put_huge_zero_folio.patch
mm-use-rwsem-assertion-macros-for-mmap_lock.patch
filemap-remove-__set_page_dirty.patch
mm-correct-page_mapped_in_vma-for-large-folios.patch
mm-remove-vma_address.patch
mm-rename-vma_pgoff_address-back-to-vma_address.patch
khugepaged-inline-hpage_collapse_alloc_folio.patch
khugepaged-convert-alloc_charge_hpage-to-alloc_charge_folio.patch
khugepaged-remove-hpage-from-collapse_huge_page.patch
khugepaged-pass-a-folio-to-__collapse_huge_page_copy.patch
khugepaged-remove-hpage-from-collapse_file.patch
khugepaged-use-a-folio-throughout-collapse_file.patch
khugepaged-use-a-folio-throughout-collapse_file-fix.patch
khugepaged-use-a-folio-throughout-hpage_collapse_scan_file.patch
proc-convert-clear_refs_pte_range-to-use-a-folio.patch
proc-convert-smaps_account-to-use-a-folio.patch
mm-remove-page_idle-and-page_young-wrappers.patch
mm-generate-page_idle_flag-definitions.patch
proc-convert-gather_stats-to-use-a-folio.patch
proc-convert-smaps_page_accumulate-to-use-a-folio.patch
proc-pass-a-folio-to-smaps_page_accumulate.patch
proc-convert-smaps_pmd_entry-to-use-a-folio.patch
mm-remove-struct-page-from-get_shadow_from_swap_cache.patch
hugetlb-convert-alloc_buddy_hugetlb_folio-to-use-a-folio.patch
mm-convert-pagecache_isize_extended-to-use-a-folio.patch
mm-free-non-hugetlb-large-folios-in-a-batch.patch
mm-combine-free_the_page-and-free_unref_page.patch
mm-inline-destroy_large_folio-into-__folio_put_large.patch
mm-combine-__folio_put_small-__folio_put_large-and-__folio_put.patch
mm-convert-free_zone_device_page-to-free_zone_device_folio.patch
doc-improve-the-description-of-__folio_mark_dirty.patch
buffer-add-kernel-doc-for-block_dirty_folio.patch
buffer-add-kernel-doc-for-try_to_free_buffers.patch
buffer-fix-__bread-and-__bread_gfp-kernel-doc.patch
buffer-add-kernel-doc-for-brelse-and-__brelse.patch
buffer-add-kernel-doc-for-bforget-and-__bforget.patch
buffer-improve-bdev_getblk-documentation.patch
doc-split-bufferrst-out-of-api-summaryrst.patch
