+ buffer-improve-bdev_getblk-documentation.patch added to mm-unstable branch

+ buffer-improve-bdev_getblk-documentation.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: buffer: improve bdev_getblk documentation
has been added to the -mm mm-unstable branch.  Its filename is
     buffer-improve-bdev_getblk-documentation.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/buffer-improve-bdev_getblk-documentation.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: buffer: improve bdev_getblk documentation
Date: Tue, 16 Apr 2024 04:17:51 +0100

Add some more information about the state of the buffer_head returned.

Link: https://lkml.kernel.org/r/20240416031754.4076917-8-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/buffer.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/fs/buffer.c~buffer-improve-bdev_getblk-documentation
+++ a/fs/buffer.c
@@ -1424,6 +1424,11 @@ EXPORT_SYMBOL(__find_get_block);
  * @size: The size of buffer_heads for this @bdev.
  * @gfp: The memory allocation flags to use.
  *
+ * The returned buffer head has its reference count incremented, but is
+ * not locked.  The caller should call brelse() when it has finished
+ * with the buffer.  The buffer may not be uptodate.  If needed, the
+ * caller can bring it uptodate either by reading it or overwriting it.
+ *
  * Return: The buffer head, or NULL if memory could not be allocated.
  */
 struct buffer_head *bdev_getblk(struct block_device *bdev, sector_t block,
_

Patches currently in -mm which might be from willy@infradead.org 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