| Message ID | 20210222063357.92930-4-wqu@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs: support read-write for subpage metadata | expand |
On Mon 22 Feb 2021 at 14:33, Qu Wenruo <wqu@suse.com> wrote: > For btree_set_page_dirty(), we should also check the extent > buffer > sanity for subpage support. > > Unlike the regular sector size case, since one page can contain > multiple > extent buffers, we need to make sure there is at least one dirty > extent > buffer in the page. > > So this patch will iterate through the > btrfs_subpage::dirty_bitmap > to get the extent buffers, and check if any dirty extent buffer > in the page > range has EXTENT_BUFFER_DIRTY and proper refs. > > Signed-off-by: Qu Wenruo <wqu@suse.com> > --- > fs/btrfs/disk-io.c | 47 > ++++++++++++++++++++++++++++++++++++++++------ > 1 file changed, 41 insertions(+), 6 deletions(-) > > diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c > index c2576c5fe62e..437e6b2163c7 100644 > --- a/fs/btrfs/disk-io.c > +++ b/fs/btrfs/disk-io.c > @@ -42,6 +42,7 @@ > #include "discard.h" > #include "space-info.h" > #include "zoned.h" > +#include "subpage.h" > > #define BTRFS_SUPER_FLAG_SUPP (BTRFS_HEADER_FLAG_WRITTEN |\ > BTRFS_HEADER_FLAG_RELOC |\ > @@ -992,14 +993,48 @@ static void btree_invalidatepage(struct > page *page, unsigned int offset, > static int btree_set_page_dirty(struct page *page) > { > #ifdef DEBUG > + struct btrfs_fs_info *fs_info = > btrfs_sb(page->mapping->host->i_sb); > + struct btrfs_subpage *subpage; > struct extent_buffer *eb; > + int cur_bit; > cur_bit is not initialized. > + u64 page_start = page_offset(page); > + > + if (fs_info->sectorsize == PAGE_SIZE) { > + BUG_ON(!PagePrivate(page)); > + eb = (struct extent_buffer *)page->private; > + BUG_ON(!eb); > + BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); > + BUG_ON(!atomic_read(&eb->refs)); > + btrfs_assert_tree_locked(eb); > + return __set_page_dirty_nobuffers(page); > + } > + ASSERT(PagePrivate(page) && page->private); > + subpage = (struct btrfs_subpage *)page->private; > + > + ASSERT(subpage->dirty_bitmap); > + while (cur_bit < BTRFS_SUBPAGE_BITMAP_SIZE) { > + unsigned long flags; > + u64 cur; > + u16 tmp = (1 << cur_bit); > + > + spin_lock_irqsave(&subpage->lock, flags); > + if (!(tmp & subpage->dirty_bitmap)) { > + spin_unlock_irqrestore(&subpage->lock, flags); > + cur_bit++; > + continue; > + } > + spin_unlock_irqrestore(&subpage->lock, flags); > + cur = page_start + cur_bit * fs_info->sectorsize; > > - BUG_ON(!PagePrivate(page)); > - eb = (struct extent_buffer *)page->private; > - BUG_ON(!eb); > - BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); > - BUG_ON(!atomic_read(&eb->refs)); > - btrfs_assert_tree_locked(eb); > + eb = find_extent_buffer(fs_info, cur); > + ASSERT(eb); > + ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); > + ASSERT(atomic_read(&eb->refs)); > + btrfs_assert_tree_locked(eb); > + free_extent_buffer(eb); > + > + cur_bit += (fs_info->nodesize >> > fs_info->sectorsize_bits); > + } > #endif > return __set_page_dirty_nobuffers(page); > }
On Mon, Feb 22, 2021 at 03:58:00PM +0800, Su Yue wrote: > > On Mon 22 Feb 2021 at 14:33, Qu Wenruo <wqu@suse.com> wrote: > > > For btree_set_page_dirty(), we should also check the extent > > buffer > > sanity for subpage support. > > > > Unlike the regular sector size case, since one page can contain > > multiple > > extent buffers, we need to make sure there is at least one dirty > > extent > > buffer in the page. > > > > So this patch will iterate through the > > btrfs_subpage::dirty_bitmap > > to get the extent buffers, and check if any dirty extent buffer > > in the page > > range has EXTENT_BUFFER_DIRTY and proper refs. > > > > Signed-off-by: Qu Wenruo <wqu@suse.com> > > --- > > fs/btrfs/disk-io.c | 47 > > ++++++++++++++++++++++++++++++++++++++++------ > > 1 file changed, 41 insertions(+), 6 deletions(-) > > > > diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c > > index c2576c5fe62e..437e6b2163c7 100644 > > --- a/fs/btrfs/disk-io.c > > +++ b/fs/btrfs/disk-io.c > > @@ -42,6 +42,7 @@ > > #include "discard.h" > > #include "space-info.h" > > #include "zoned.h" > > +#include "subpage.h" > > > > #define BTRFS_SUPER_FLAG_SUPP (BTRFS_HEADER_FLAG_WRITTEN |\ > > BTRFS_HEADER_FLAG_RELOC |\ > > @@ -992,14 +993,48 @@ static void btree_invalidatepage(struct > > page *page, unsigned int offset, > > static int btree_set_page_dirty(struct page *page) > > { > > #ifdef DEBUG > > + struct btrfs_fs_info *fs_info = > > btrfs_sb(page->mapping->host->i_sb); > > + struct btrfs_subpage *subpage; > > struct extent_buffer *eb; > > + int cur_bit; > > > cur_bit is not initialized. Indeed and it's strange that gcc does not warn about that, either by default or with W=3.
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index c2576c5fe62e..437e6b2163c7 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -42,6 +42,7 @@ #include "discard.h" #include "space-info.h" #include "zoned.h" +#include "subpage.h" #define BTRFS_SUPER_FLAG_SUPP (BTRFS_HEADER_FLAG_WRITTEN |\ BTRFS_HEADER_FLAG_RELOC |\ @@ -992,14 +993,48 @@ static void btree_invalidatepage(struct page *page, unsigned int offset, static int btree_set_page_dirty(struct page *page) { #ifdef DEBUG + struct btrfs_fs_info *fs_info = btrfs_sb(page->mapping->host->i_sb); + struct btrfs_subpage *subpage; struct extent_buffer *eb; + int cur_bit; + u64 page_start = page_offset(page); + + if (fs_info->sectorsize == PAGE_SIZE) { + BUG_ON(!PagePrivate(page)); + eb = (struct extent_buffer *)page->private; + BUG_ON(!eb); + BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); + BUG_ON(!atomic_read(&eb->refs)); + btrfs_assert_tree_locked(eb); + return __set_page_dirty_nobuffers(page); + } + ASSERT(PagePrivate(page) && page->private); + subpage = (struct btrfs_subpage *)page->private; + + ASSERT(subpage->dirty_bitmap); + while (cur_bit < BTRFS_SUBPAGE_BITMAP_SIZE) { + unsigned long flags; + u64 cur; + u16 tmp = (1 << cur_bit); + + spin_lock_irqsave(&subpage->lock, flags); + if (!(tmp & subpage->dirty_bitmap)) { + spin_unlock_irqrestore(&subpage->lock, flags); + cur_bit++; + continue; + } + spin_unlock_irqrestore(&subpage->lock, flags); + cur = page_start + cur_bit * fs_info->sectorsize; - BUG_ON(!PagePrivate(page)); - eb = (struct extent_buffer *)page->private; - BUG_ON(!eb); - BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); - BUG_ON(!atomic_read(&eb->refs)); - btrfs_assert_tree_locked(eb); + eb = find_extent_buffer(fs_info, cur); + ASSERT(eb); + ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); + ASSERT(atomic_read(&eb->refs)); + btrfs_assert_tree_locked(eb); + free_extent_buffer(eb); + + cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits); + } #endif return __set_page_dirty_nobuffers(page); }
For btree_set_page_dirty(), we should also check the extent buffer sanity for subpage support. Unlike the regular sector size case, since one page can contain multiple extent buffers, we need to make sure there is at least one dirty extent buffer in the page. So this patch will iterate through the btrfs_subpage::dirty_bitmap to get the extent buffers, and check if any dirty extent buffer in the page range has EXTENT_BUFFER_DIRTY and proper refs. Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/disk-io.c | 47 ++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 41 insertions(+), 6 deletions(-)