summaryrefslogtreecommitdiff
path: root/fs/btrfs/subpage.h
diff options
context:
space:
mode:
Diffstat (limited to 'fs/btrfs/subpage.h')
-rw-r--r--fs/btrfs/subpage.h104
1 files changed, 57 insertions, 47 deletions
diff --git a/fs/btrfs/subpage.h b/fs/btrfs/subpage.h
index 793c2b314a58..44fff1f4eac4 100644
--- a/fs/btrfs/subpage.h
+++ b/fs/btrfs/subpage.h
@@ -4,6 +4,12 @@
#define BTRFS_SUBPAGE_H
#include <linux/spinlock.h>
+#include <linux/atomic.h>
+#include <linux/sizes.h>
+
+struct address_space;
+struct folio;
+struct btrfs_fs_info;
/*
* Extra info for subpapge bitmap.
@@ -13,29 +19,23 @@
*
* This structure records how they are organized in the bitmap:
*
- * /- uptodate_offset /- dirty_offset /- ordered_offset
+ * /- uptodate /- dirty /- ordered
* | | |
* v v v
* |u|u|u|u|........|u|u|d|d|.......|d|d|o|o|.......|o|o|
- * |<- bitmap_nr_bits ->|
- * |<----------------- total_nr_bits ------------------>|
+ * |< sectors_per_page >|
+ *
+ * Unlike regular macro-like enums, here we do not go upper-case names, as
+ * these names will be utilized in various macros to define function names.
*/
-struct btrfs_subpage_info {
- /* Number of bits for each bitmap */
- unsigned int bitmap_nr_bits;
-
- /* Total number of bits for the whole bitmap */
- unsigned int total_nr_bits;
-
- /*
- * *_start indicates where the bitmap starts, the length is always
- * @bitmap_size, which is calculated from PAGE_SIZE / sectorsize.
- */
- unsigned int uptodate_offset;
- unsigned int dirty_offset;
- unsigned int writeback_offset;
- unsigned int ordered_offset;
- unsigned int checked_offset;
+enum {
+ btrfs_bitmap_nr_uptodate = 0,
+ btrfs_bitmap_nr_dirty,
+ btrfs_bitmap_nr_writeback,
+ btrfs_bitmap_nr_ordered,
+ btrfs_bitmap_nr_checked,
+ btrfs_bitmap_nr_locked,
+ btrfs_bitmap_nr_max
};
/*
@@ -45,14 +45,6 @@ struct btrfs_subpage_info {
struct btrfs_subpage {
/* Common members for both data and metadata pages */
spinlock_t lock;
- /*
- * Both data and metadata needs to track how many readers are for the
- * page.
- * Data relies on @readers to unlock the page when last reader finished.
- * While metadata doesn't need page unlock, it needs to prevent
- * page::private get cleared before the last end_page_read().
- */
- atomic_t readers;
union {
/*
* Structures only used by metadata
@@ -62,8 +54,12 @@ struct btrfs_subpage {
*/
atomic_t eb_refs;
- /* Structures only used by data */
- atomic_t writers;
+ /*
+ * Structures only used by data,
+ *
+ * How many sectors inside the page is locked.
+ */
+ atomic_t nr_locked;
};
unsigned long bitmaps[];
};
@@ -73,9 +69,16 @@ enum btrfs_subpage_type {
BTRFS_SUBPAGE_DATA,
};
+#if PAGE_SIZE > SZ_4K
bool btrfs_is_subpage(const struct btrfs_fs_info *fs_info, struct address_space *mapping);
+#else
+static inline bool btrfs_is_subpage(const struct btrfs_fs_info *fs_info,
+ struct address_space *mapping)
+{
+ return false;
+}
+#endif
-void btrfs_init_subpage_info(struct btrfs_subpage_info *subpage_info, u32 sectorsize);
int btrfs_attach_subpage(const struct btrfs_fs_info *fs_info,
struct folio *folio, enum btrfs_subpage_type type);
void btrfs_detach_subpage(const struct btrfs_fs_info *fs_info, struct folio *folio);
@@ -88,20 +91,12 @@ void btrfs_free_subpage(struct btrfs_subpage *subpage);
void btrfs_folio_inc_eb_refs(const struct btrfs_fs_info *fs_info, struct folio *folio);
void btrfs_folio_dec_eb_refs(const struct btrfs_fs_info *fs_info, struct folio *folio);
-void btrfs_subpage_start_reader(const struct btrfs_fs_info *fs_info,
- struct folio *folio, u64 start, u32 len);
-void btrfs_subpage_end_reader(const struct btrfs_fs_info *fs_info,
- struct folio *folio, u64 start, u32 len);
-
-void btrfs_subpage_start_writer(const struct btrfs_fs_info *fs_info,
- struct folio *folio, u64 start, u32 len);
-bool btrfs_subpage_end_and_test_writer(const struct btrfs_fs_info *fs_info,
- struct folio *folio, u64 start, u32 len);
-int btrfs_folio_start_writer_lock(const struct btrfs_fs_info *fs_info,
- struct folio *folio, u64 start, u32 len);
-void btrfs_folio_end_writer_lock(const struct btrfs_fs_info *fs_info,
- struct folio *folio, u64 start, u32 len);
-
+void btrfs_folio_end_lock(const struct btrfs_fs_info *fs_info,
+ struct folio *folio, u64 start, u32 len);
+void btrfs_folio_set_lock(const struct btrfs_fs_info *fs_info,
+ struct folio *folio, u64 start, u32 len);
+void btrfs_folio_end_lock_bitmap(const struct btrfs_fs_info *fs_info,
+ struct folio *folio, unsigned long bitmap);
/*
* Template for subpage related operations.
*
@@ -142,12 +137,27 @@ DECLARE_BTRFS_SUBPAGE_OPS(writeback);
DECLARE_BTRFS_SUBPAGE_OPS(ordered);
DECLARE_BTRFS_SUBPAGE_OPS(checked);
+/*
+ * Helper for error cleanup, where a folio will have its dirty flag cleared,
+ * with writeback started and finished.
+ */
+static inline void btrfs_folio_clamp_finish_io(struct btrfs_fs_info *fs_info,
+ struct folio *locked_folio,
+ u64 start, u32 len)
+{
+ btrfs_folio_clamp_clear_dirty(fs_info, locked_folio, start, len);
+ btrfs_folio_clamp_set_writeback(fs_info, locked_folio, start, len);
+ btrfs_folio_clamp_clear_writeback(fs_info, locked_folio, start, len);
+}
+
bool btrfs_subpage_clear_and_test_dirty(const struct btrfs_fs_info *fs_info,
struct folio *folio, u64 start, u32 len);
-void btrfs_folio_assert_not_dirty(const struct btrfs_fs_info *fs_info, struct folio *folio);
-void btrfs_folio_unlock_writer(struct btrfs_fs_info *fs_info,
- struct folio *folio, u64 start, u32 len);
+void btrfs_folio_assert_not_dirty(const struct btrfs_fs_info *fs_info,
+ struct folio *folio, u64 start, u32 len);
+void btrfs_get_subpage_dirty_bitmap(struct btrfs_fs_info *fs_info,
+ struct folio *folio,
+ unsigned long *ret_bitmap);
void __cold btrfs_subpage_dump_bitmap(const struct btrfs_fs_info *fs_info,
struct folio *folio, u64 start, u32 len);