v4.19.13 snapshot.
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
new file mode 100644
index 0000000..b4d03e6
--- /dev/null
+++ b/fs/btrfs/extent_io.h
@@ -0,0 +1,557 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_EXTENT_IO_H
+#define BTRFS_EXTENT_IO_H
+
+#include <linux/rbtree.h>
+#include <linux/refcount.h>
+#include "ulist.h"
+
+/* bits for the extent state */
+#define EXTENT_DIRTY (1U << 0)
+#define EXTENT_WRITEBACK (1U << 1)
+#define EXTENT_UPTODATE (1U << 2)
+#define EXTENT_LOCKED (1U << 3)
+#define EXTENT_NEW (1U << 4)
+#define EXTENT_DELALLOC (1U << 5)
+#define EXTENT_DEFRAG (1U << 6)
+#define EXTENT_BOUNDARY (1U << 9)
+#define EXTENT_NODATASUM (1U << 10)
+#define EXTENT_CLEAR_META_RESV (1U << 11)
+#define EXTENT_FIRST_DELALLOC (1U << 12)
+#define EXTENT_NEED_WAIT (1U << 13)
+#define EXTENT_DAMAGED (1U << 14)
+#define EXTENT_NORESERVE (1U << 15)
+#define EXTENT_QGROUP_RESERVED (1U << 16)
+#define EXTENT_CLEAR_DATA_RESV (1U << 17)
+#define EXTENT_DELALLOC_NEW (1U << 18)
+#define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
+#define EXTENT_DO_ACCOUNTING (EXTENT_CLEAR_META_RESV | \
+ EXTENT_CLEAR_DATA_RESV)
+#define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
+
+/*
+ * flags for bio submission. The high bits indicate the compression
+ * type for this bio
+ */
+#define EXTENT_BIO_COMPRESSED 1
+#define EXTENT_BIO_FLAG_SHIFT 16
+
+/* these are bit numbers for test/set bit */
+#define EXTENT_BUFFER_UPTODATE 0
+#define EXTENT_BUFFER_DIRTY 2
+#define EXTENT_BUFFER_CORRUPT 3
+#define EXTENT_BUFFER_READAHEAD 4 /* this got triggered by readahead */
+#define EXTENT_BUFFER_TREE_REF 5
+#define EXTENT_BUFFER_STALE 6
+#define EXTENT_BUFFER_WRITEBACK 7
+#define EXTENT_BUFFER_READ_ERR 8 /* read IO error */
+#define EXTENT_BUFFER_UNMAPPED 9
+#define EXTENT_BUFFER_IN_TREE 10
+#define EXTENT_BUFFER_WRITE_ERR 11 /* write IO error */
+
+/* these are flags for __process_pages_contig */
+#define PAGE_UNLOCK (1 << 0)
+#define PAGE_CLEAR_DIRTY (1 << 1)
+#define PAGE_SET_WRITEBACK (1 << 2)
+#define PAGE_END_WRITEBACK (1 << 3)
+#define PAGE_SET_PRIVATE2 (1 << 4)
+#define PAGE_SET_ERROR (1 << 5)
+#define PAGE_LOCK (1 << 6)
+
+/*
+ * page->private values. Every page that is controlled by the extent
+ * map has page->private set to one.
+ */
+#define EXTENT_PAGE_PRIVATE 1
+
+/*
+ * The extent buffer bitmap operations are done with byte granularity instead of
+ * word granularity for two reasons:
+ * 1. The bitmaps must be little-endian on disk.
+ * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
+ * single word in a bitmap may straddle two pages in the extent buffer.
+ */
+#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
+#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
+#define BITMAP_FIRST_BYTE_MASK(start) \
+ ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
+#define BITMAP_LAST_BYTE_MASK(nbits) \
+ (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
+
+struct extent_state;
+struct btrfs_root;
+struct btrfs_inode;
+struct btrfs_io_bio;
+struct io_failure_record;
+
+typedef blk_status_t (extent_submit_bio_hook_t)(void *private_data, struct bio *bio,
+ int mirror_num, unsigned long bio_flags,
+ u64 bio_offset);
+
+typedef blk_status_t (extent_submit_bio_start_t)(void *private_data,
+ struct bio *bio, u64 bio_offset);
+
+struct extent_io_ops {
+ /*
+ * The following callbacks must be allways defined, the function
+ * pointer will be called unconditionally.
+ */
+ extent_submit_bio_hook_t *submit_bio_hook;
+ int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
+ struct page *page, u64 start, u64 end,
+ int mirror);
+ int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
+
+ /*
+ * Optional hooks, called if the pointer is not NULL
+ */
+ int (*fill_delalloc)(void *private_data, struct page *locked_page,
+ u64 start, u64 end, int *page_started,
+ unsigned long *nr_written,
+ struct writeback_control *wbc);
+
+ int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
+ void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
+ struct extent_state *state, int uptodate);
+ void (*set_bit_hook)(void *private_data, struct extent_state *state,
+ unsigned *bits);
+ void (*clear_bit_hook)(void *private_data,
+ struct extent_state *state,
+ unsigned *bits);
+ void (*merge_extent_hook)(void *private_data,
+ struct extent_state *new,
+ struct extent_state *other);
+ void (*split_extent_hook)(void *private_data,
+ struct extent_state *orig, u64 split);
+ void (*check_extent_io_range)(void *private_data, const char *caller,
+ u64 start, u64 end);
+};
+
+struct extent_io_tree {
+ struct rb_root state;
+ void *private_data;
+ u64 dirty_bytes;
+ int track_uptodate;
+ spinlock_t lock;
+ const struct extent_io_ops *ops;
+};
+
+struct extent_state {
+ u64 start;
+ u64 end; /* inclusive */
+ struct rb_node rb_node;
+
+ /* ADD NEW ELEMENTS AFTER THIS */
+ wait_queue_head_t wq;
+ refcount_t refs;
+ unsigned state;
+
+ struct io_failure_record *failrec;
+
+#ifdef CONFIG_BTRFS_DEBUG
+ struct list_head leak_list;
+#endif
+};
+
+#define INLINE_EXTENT_BUFFER_PAGES 16
+#define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE)
+struct extent_buffer {
+ u64 start;
+ unsigned long len;
+ unsigned long bflags;
+ struct btrfs_fs_info *fs_info;
+ spinlock_t refs_lock;
+ atomic_t refs;
+ atomic_t io_pages;
+ int read_mirror;
+ struct rcu_head rcu_head;
+ pid_t lock_owner;
+
+ /* count of read lock holders on the extent buffer */
+ atomic_t write_locks;
+ atomic_t read_locks;
+ atomic_t blocking_writers;
+ atomic_t blocking_readers;
+ atomic_t spinning_readers;
+ atomic_t spinning_writers;
+ short lock_nested;
+ /* >= 0 if eb belongs to a log tree, -1 otherwise */
+ short log_index;
+
+ /* protects write locks */
+ rwlock_t lock;
+
+ /* readers use lock_wq while they wait for the write
+ * lock holders to unlock
+ */
+ wait_queue_head_t write_lock_wq;
+
+ /* writers use read_lock_wq while they wait for readers
+ * to unlock
+ */
+ wait_queue_head_t read_lock_wq;
+ struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
+#ifdef CONFIG_BTRFS_DEBUG
+ struct list_head leak_list;
+#endif
+};
+
+/*
+ * Structure to record how many bytes and which ranges are set/cleared
+ */
+struct extent_changeset {
+ /* How many bytes are set/cleared in this operation */
+ unsigned int bytes_changed;
+
+ /* Changed ranges */
+ struct ulist range_changed;
+};
+
+static inline void extent_changeset_init(struct extent_changeset *changeset)
+{
+ changeset->bytes_changed = 0;
+ ulist_init(&changeset->range_changed);
+}
+
+static inline struct extent_changeset *extent_changeset_alloc(void)
+{
+ struct extent_changeset *ret;
+
+ ret = kmalloc(sizeof(*ret), GFP_KERNEL);
+ if (!ret)
+ return NULL;
+
+ extent_changeset_init(ret);
+ return ret;
+}
+
+static inline void extent_changeset_release(struct extent_changeset *changeset)
+{
+ if (!changeset)
+ return;
+ changeset->bytes_changed = 0;
+ ulist_release(&changeset->range_changed);
+}
+
+static inline void extent_changeset_free(struct extent_changeset *changeset)
+{
+ if (!changeset)
+ return;
+ extent_changeset_release(changeset);
+ kfree(changeset);
+}
+
+static inline void extent_set_compress_type(unsigned long *bio_flags,
+ int compress_type)
+{
+ *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
+}
+
+static inline int extent_compress_type(unsigned long bio_flags)
+{
+ return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
+}
+
+struct extent_map_tree;
+
+typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode,
+ struct page *page,
+ size_t pg_offset,
+ u64 start, u64 len,
+ int create);
+
+void extent_io_tree_init(struct extent_io_tree *tree, void *private_data);
+int try_release_extent_mapping(struct page *page, gfp_t mask);
+int try_release_extent_buffer(struct page *page);
+int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
+ struct extent_state **cached);
+
+static inline int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
+{
+ return lock_extent_bits(tree, start, end, NULL);
+}
+
+int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
+int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
+ get_extent_t *get_extent, int mirror_num);
+int __init extent_io_init(void);
+void __cold extent_io_exit(void);
+
+u64 count_range_bits(struct extent_io_tree *tree,
+ u64 *start, u64 search_end,
+ u64 max_bytes, unsigned bits, int contig);
+
+void free_extent_state(struct extent_state *state);
+int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
+ unsigned bits, int filled,
+ struct extent_state *cached_state);
+int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
+ unsigned bits, struct extent_changeset *changeset);
+int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
+ unsigned bits, int wake, int delete,
+ struct extent_state **cached);
+int __clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
+ unsigned bits, int wake, int delete,
+ struct extent_state **cached, gfp_t mask,
+ struct extent_changeset *changeset);
+
+static inline int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
+{
+ return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL);
+}
+
+static inline int unlock_extent_cached(struct extent_io_tree *tree, u64 start,
+ u64 end, struct extent_state **cached)
+{
+ return __clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
+ GFP_NOFS, NULL);
+}
+
+static inline int unlock_extent_cached_atomic(struct extent_io_tree *tree,
+ u64 start, u64 end, struct extent_state **cached)
+{
+ return __clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
+ GFP_ATOMIC, NULL);
+}
+
+static inline int clear_extent_bits(struct extent_io_tree *tree, u64 start,
+ u64 end, unsigned bits)
+{
+ int wake = 0;
+
+ if (bits & EXTENT_LOCKED)
+ wake = 1;
+
+ return clear_extent_bit(tree, start, end, bits, wake, 0, NULL);
+}
+
+int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
+ unsigned bits, struct extent_changeset *changeset);
+int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
+ unsigned bits, u64 *failed_start,
+ struct extent_state **cached_state, gfp_t mask);
+
+static inline int set_extent_bits(struct extent_io_tree *tree, u64 start,
+ u64 end, unsigned bits)
+{
+ return set_extent_bit(tree, start, end, bits, NULL, NULL, GFP_NOFS);
+}
+
+static inline int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
+ u64 end, struct extent_state **cached_state)
+{
+ return __clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
+ cached_state, GFP_NOFS, NULL);
+}
+
+static inline int set_extent_dirty(struct extent_io_tree *tree, u64 start,
+ u64 end, gfp_t mask)
+{
+ return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
+ NULL, mask);
+}
+
+static inline int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
+ u64 end)
+{
+ return clear_extent_bit(tree, start, end,
+ EXTENT_DIRTY | EXTENT_DELALLOC |
+ EXTENT_DO_ACCOUNTING, 0, 0, NULL);
+}
+
+int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
+ unsigned bits, unsigned clear_bits,
+ struct extent_state **cached_state);
+
+static inline int set_extent_delalloc(struct extent_io_tree *tree, u64 start,
+ u64 end, unsigned int extra_bits,
+ struct extent_state **cached_state)
+{
+ return set_extent_bit(tree, start, end,
+ EXTENT_DELALLOC | EXTENT_UPTODATE | extra_bits,
+ NULL, cached_state, GFP_NOFS);
+}
+
+static inline int set_extent_defrag(struct extent_io_tree *tree, u64 start,
+ u64 end, struct extent_state **cached_state)
+{
+ return set_extent_bit(tree, start, end,
+ EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
+ NULL, cached_state, GFP_NOFS);
+}
+
+static inline int set_extent_new(struct extent_io_tree *tree, u64 start,
+ u64 end)
+{
+ return set_extent_bit(tree, start, end, EXTENT_NEW, NULL, NULL,
+ GFP_NOFS);
+}
+
+static inline int set_extent_uptodate(struct extent_io_tree *tree, u64 start,
+ u64 end, struct extent_state **cached_state, gfp_t mask)
+{
+ return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
+ cached_state, mask);
+}
+
+int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
+ u64 *start_ret, u64 *end_ret, unsigned bits,
+ struct extent_state **cached_state);
+int extent_invalidatepage(struct extent_io_tree *tree,
+ struct page *page, unsigned long offset);
+int extent_write_full_page(struct page *page, struct writeback_control *wbc);
+int extent_write_locked_range(struct inode *inode, u64 start, u64 end,
+ int mode);
+int extent_writepages(struct address_space *mapping,
+ struct writeback_control *wbc);
+int btree_write_cache_pages(struct address_space *mapping,
+ struct writeback_control *wbc);
+int extent_readpages(struct address_space *mapping, struct list_head *pages,
+ unsigned nr_pages);
+int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+ __u64 start, __u64 len);
+void set_page_extent_mapped(struct page *page);
+
+struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
+ u64 start);
+struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
+ u64 start, unsigned long len);
+struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
+ u64 start);
+struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
+struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
+ u64 start);
+void free_extent_buffer(struct extent_buffer *eb);
+void free_extent_buffer_stale(struct extent_buffer *eb);
+#define WAIT_NONE 0
+#define WAIT_COMPLETE 1
+#define WAIT_PAGE_LOCK 2
+int read_extent_buffer_pages(struct extent_io_tree *tree,
+ struct extent_buffer *eb, int wait,
+ int mirror_num);
+void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
+
+static inline int num_extent_pages(const struct extent_buffer *eb)
+{
+ return (round_up(eb->start + eb->len, PAGE_SIZE) >> PAGE_SHIFT) -
+ (eb->start >> PAGE_SHIFT);
+}
+
+static inline void extent_buffer_get(struct extent_buffer *eb)
+{
+ atomic_inc(&eb->refs);
+}
+
+static inline int extent_buffer_uptodate(struct extent_buffer *eb)
+{
+ return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
+}
+
+int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
+ unsigned long start, unsigned long len);
+void read_extent_buffer(const struct extent_buffer *eb, void *dst,
+ unsigned long start,
+ unsigned long len);
+int read_extent_buffer_to_user(const struct extent_buffer *eb,
+ void __user *dst, unsigned long start,
+ unsigned long len);
+void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src);
+void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
+ const void *src);
+void write_extent_buffer(struct extent_buffer *eb, const void *src,
+ unsigned long start, unsigned long len);
+void copy_extent_buffer_full(struct extent_buffer *dst,
+ struct extent_buffer *src);
+void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
+ unsigned long dst_offset, unsigned long src_offset,
+ unsigned long len);
+void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
+ unsigned long src_offset, unsigned long len);
+void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
+ unsigned long src_offset, unsigned long len);
+void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start,
+ unsigned long len);
+int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
+ unsigned long pos);
+void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
+ unsigned long pos, unsigned long len);
+void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
+ unsigned long pos, unsigned long len);
+void clear_extent_buffer_dirty(struct extent_buffer *eb);
+int set_extent_buffer_dirty(struct extent_buffer *eb);
+void set_extent_buffer_uptodate(struct extent_buffer *eb);
+void clear_extent_buffer_uptodate(struct extent_buffer *eb);
+int extent_buffer_under_io(struct extent_buffer *eb);
+int map_private_extent_buffer(const struct extent_buffer *eb,
+ unsigned long offset, unsigned long min_len,
+ char **map, unsigned long *map_start,
+ unsigned long *map_len);
+void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
+void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
+void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
+ u64 delalloc_end, struct page *locked_page,
+ unsigned bits_to_clear,
+ unsigned long page_ops);
+struct bio *btrfs_bio_alloc(struct block_device *bdev, u64 first_byte);
+struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs);
+struct bio *btrfs_bio_clone(struct bio *bio);
+struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size);
+
+struct btrfs_fs_info;
+struct btrfs_inode;
+
+int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
+ u64 length, u64 logical, struct page *page,
+ unsigned int pg_offset, int mirror_num);
+int clean_io_failure(struct btrfs_fs_info *fs_info,
+ struct extent_io_tree *failure_tree,
+ struct extent_io_tree *io_tree, u64 start,
+ struct page *page, u64 ino, unsigned int pg_offset);
+void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
+int repair_eb_io_failure(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *eb, int mirror_num);
+
+/*
+ * When IO fails, either with EIO or csum verification fails, we
+ * try other mirrors that might have a good copy of the data. This
+ * io_failure_record is used to record state as we go through all the
+ * mirrors. If another mirror has good data, the page is set up to date
+ * and things continue. If a good mirror can't be found, the original
+ * bio end_io callback is called to indicate things have failed.
+ */
+struct io_failure_record {
+ struct page *page;
+ u64 start;
+ u64 len;
+ u64 logical;
+ unsigned long bio_flags;
+ int this_mirror;
+ int failed_mirror;
+ int in_validation;
+};
+
+
+void btrfs_free_io_failure_record(struct btrfs_inode *inode, u64 start,
+ u64 end);
+int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
+ struct io_failure_record **failrec_ret);
+bool btrfs_check_repairable(struct inode *inode, unsigned failed_bio_pages,
+ struct io_failure_record *failrec, int fail_mirror);
+struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
+ struct io_failure_record *failrec,
+ struct page *page, int pg_offset, int icsum,
+ bio_end_io_t *endio_func, void *data);
+int free_io_failure(struct extent_io_tree *failure_tree,
+ struct extent_io_tree *io_tree,
+ struct io_failure_record *rec);
+#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
+noinline u64 find_lock_delalloc_range(struct inode *inode,
+ struct extent_io_tree *tree,
+ struct page *locked_page, u64 *start,
+ u64 *end, u64 max_bytes);
+#endif
+struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
+ u64 start);
+
+#endif