| Message ID | 20250121054054.4008049-1-willy@infradead.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/3] btrfs: Fix some folio-related comments | expand |
在 2025/1/21 16:10, Matthew Wilcox (Oracle) 写道: > Remove references to the page lock and page->mapping. Also > btrfs folios can never be swizzled into swap. > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Qu Wenruo <wqu@suse.com> Thanks, Qu > --- > fs/btrfs/extent_io.c | 8 +++----- > fs/btrfs/inode.c | 2 +- > fs/btrfs/subpage.c | 2 +- > 3 files changed, 5 insertions(+), 7 deletions(-) > > diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c > index d9f856358704..289ecb8ce217 100644 > --- a/fs/btrfs/extent_io.c > +++ b/fs/btrfs/extent_io.c > @@ -2189,10 +2189,8 @@ static int extent_write_cache_pages(struct address_space *mapping, > done_index = folio_next_index(folio); > /* > * At this point we hold neither the i_pages lock nor > - * the page lock: the page may be truncated or > - * invalidated (changing page->mapping to NULL), > - * or even swizzled back from swapper_space to > - * tmpfs file mapping > + * the folio lock: the folio may be truncated or > + * invalidated (changing folio->mapping to NULL) > */ > if (!folio_trylock(folio)) { > submit_write_bio(bio_ctrl, 0); > @@ -3222,7 +3220,7 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, > } > /* > * Now all pages of that extent buffer is unmapped, set UNMAPPED flag, > - * so it can be cleaned up without utilizing page->mapping. > + * so it can be cleaned up without utilizing folio->mapping. > */ > set_bit(EXTENT_BUFFER_UNMAPPED, &eb->bflags); > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index fe2c810335ff..e6ea4f172b50 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -2891,7 +2891,7 @@ int btrfs_writepage_cow_fixup(struct folio *folio) > * We are already holding a reference to this inode from > * write_cache_pages. We need to hold it because the space reservation > * takes place outside of the folio lock, and we can't trust > - * page->mapping outside of the folio lock. > + * folio->mapping outside of the folio lock. > */ > ihold(inode); > btrfs_folio_set_checked(fs_info, folio, folio_pos(folio), folio_size(folio)); > diff --git a/fs/btrfs/subpage.c b/fs/btrfs/subpage.c > index 722acf768396..6a8636c0ffed 100644 > --- a/fs/btrfs/subpage.c > +++ b/fs/btrfs/subpage.c > @@ -72,7 +72,7 @@ bool btrfs_is_subpage(const struct btrfs_fs_info *fs_info, struct address_space > > /* > * Only data pages (either through DIO or compression) can have no > - * mapping. And if page->mapping->host is data inode, it's subpage. > + * mapping. And if mapping->host is data inode, it's subpage. > * As we have ruled our sectorsize >= PAGE_SIZE case already. > */ > if (!mapping || !mapping->host || is_data_inode(BTRFS_I(mapping->host)))
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index d9f856358704..289ecb8ce217 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2189,10 +2189,8 @@ static int extent_write_cache_pages(struct address_space *mapping, done_index = folio_next_index(folio); /* * At this point we hold neither the i_pages lock nor - * the page lock: the page may be truncated or - * invalidated (changing page->mapping to NULL), - * or even swizzled back from swapper_space to - * tmpfs file mapping + * the folio lock: the folio may be truncated or + * invalidated (changing folio->mapping to NULL) */ if (!folio_trylock(folio)) { submit_write_bio(bio_ctrl, 0); @@ -3222,7 +3220,7 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, } /* * Now all pages of that extent buffer is unmapped, set UNMAPPED flag, - * so it can be cleaned up without utilizing page->mapping. + * so it can be cleaned up without utilizing folio->mapping. */ set_bit(EXTENT_BUFFER_UNMAPPED, &eb->bflags); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index fe2c810335ff..e6ea4f172b50 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2891,7 +2891,7 @@ int btrfs_writepage_cow_fixup(struct folio *folio) * We are already holding a reference to this inode from * write_cache_pages. We need to hold it because the space reservation * takes place outside of the folio lock, and we can't trust - * page->mapping outside of the folio lock. + * folio->mapping outside of the folio lock. */ ihold(inode); btrfs_folio_set_checked(fs_info, folio, folio_pos(folio), folio_size(folio)); diff --git a/fs/btrfs/subpage.c b/fs/btrfs/subpage.c index 722acf768396..6a8636c0ffed 100644 --- a/fs/btrfs/subpage.c +++ b/fs/btrfs/subpage.c @@ -72,7 +72,7 @@ bool btrfs_is_subpage(const struct btrfs_fs_info *fs_info, struct address_space /* * Only data pages (either through DIO or compression) can have no - * mapping. And if page->mapping->host is data inode, it's subpage. + * mapping. And if mapping->host is data inode, it's subpage. * As we have ruled our sectorsize >= PAGE_SIZE case already. */ if (!mapping || !mapping->host || is_data_inode(BTRFS_I(mapping->host)))
Remove references to the page lock and page->mapping. Also btrfs folios can never be swizzled into swap. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- fs/btrfs/extent_io.c | 8 +++----- fs/btrfs/inode.c | 2 +- fs/btrfs/subpage.c | 2 +- 3 files changed, 5 insertions(+), 7 deletions(-)