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v6.8
  1/* SPDX-License-Identifier: GPL-2.0 */
  2
  3#ifndef BTRFS_EXTENT_IO_H
  4#define BTRFS_EXTENT_IO_H
  5
  6#include <linux/rbtree.h>
  7#include <linux/refcount.h>
  8#include <linux/fiemap.h>
  9#include <linux/btrfs_tree.h>
 10#include "compression.h"
 11#include "ulist.h"
 12#include "misc.h"
 13
 14struct btrfs_trans_handle;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 15
 16enum {
 17	EXTENT_BUFFER_UPTODATE,
 18	EXTENT_BUFFER_DIRTY,
 19	EXTENT_BUFFER_CORRUPT,
 20	/* this got triggered by readahead */
 21	EXTENT_BUFFER_READAHEAD,
 22	EXTENT_BUFFER_TREE_REF,
 23	EXTENT_BUFFER_STALE,
 24	EXTENT_BUFFER_WRITEBACK,
 25	/* read IO error */
 26	EXTENT_BUFFER_READ_ERR,
 27	EXTENT_BUFFER_UNMAPPED,
 28	EXTENT_BUFFER_IN_TREE,
 29	/* write IO error */
 30	EXTENT_BUFFER_WRITE_ERR,
 31	/* Indicate the extent buffer is written zeroed out (for zoned) */
 32	EXTENT_BUFFER_ZONED_ZEROOUT,
 33	/* Indicate that extent buffer pages a being read */
 34	EXTENT_BUFFER_READING,
 35};
 36
 37/* these are flags for __process_pages_contig */
 38enum {
 39	ENUM_BIT(PAGE_UNLOCK),
 40	/* Page starts writeback, clear dirty bit and set writeback bit */
 41	ENUM_BIT(PAGE_START_WRITEBACK),
 42	ENUM_BIT(PAGE_END_WRITEBACK),
 43	ENUM_BIT(PAGE_SET_ORDERED),
 44};
 45
 46/*
 47 * Folio private values.  Every page that is controlled by the extent map has
 48 * folio private set to this value.
 49 */
 50#define EXTENT_FOLIO_PRIVATE			1
 51
 52/*
 53 * The extent buffer bitmap operations are done with byte granularity instead of
 54 * word granularity for two reasons:
 55 * 1. The bitmaps must be little-endian on disk.
 56 * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
 57 *    single word in a bitmap may straddle two pages in the extent buffer.
 58 */
 59#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
 60#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
 61#define BITMAP_FIRST_BYTE_MASK(start) \
 62	((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
 63#define BITMAP_LAST_BYTE_MASK(nbits) \
 64	(BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
 65
 
 
 
 
 
 
 
 
 
 66struct btrfs_root;
 67struct btrfs_inode;
 68struct btrfs_fs_info;
 69struct extent_io_tree;
 70struct btrfs_tree_parent_check;
 
 
 
 
 
 
 
 
 
 71
 72int __init extent_buffer_init_cachep(void);
 73void __cold extent_buffer_free_cachep(void);
 
 
 
 
 
 
 
 
 
 
 
 
 
 74
 75#define INLINE_EXTENT_BUFFER_PAGES     (BTRFS_MAX_METADATA_BLOCKSIZE / PAGE_SIZE)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 76struct extent_buffer {
 77	u64 start;
 78	unsigned long len;
 79	unsigned long bflags;
 80	struct btrfs_fs_info *fs_info;
 81
 82	/*
 83	 * The address where the eb can be accessed without any cross-page handling.
 84	 * This can be NULL if not possible.
 85	 */
 86	void *addr;
 87
 88	spinlock_t refs_lock;
 89	atomic_t refs;
 
 90	int read_mirror;
 91	/* >= 0 if eb belongs to a log tree, -1 otherwise */
 92	s8 log_index;
 93	struct rcu_head rcu_head;
 
 94
 95	struct rw_semaphore lock;
 
 
 
 
 
 
 
 
 
 96
 97	/*
 98	 * Pointers to all the folios of the extent buffer.
 99	 *
100	 * For now the folio is always order 0 (aka, a single page).
 
 
 
 
 
 
101	 */
102	struct folio *folios[INLINE_EXTENT_BUFFER_PAGES];
 
103#ifdef CONFIG_BTRFS_DEBUG
104	struct list_head leak_list;
105	pid_t lock_owner;
106#endif
107};
108
109struct btrfs_eb_write_context {
110	struct writeback_control *wbc;
111	struct extent_buffer *eb;
112	/* Block group @eb resides in. Only used for zoned mode. */
113	struct btrfs_block_group *zoned_bg;
114};
115
116/*
117 * Get the correct offset inside the page of extent buffer.
118 *
119 * @eb:		target extent buffer
120 * @start:	offset inside the extent buffer
121 *
122 * Will handle both sectorsize == PAGE_SIZE and sectorsize < PAGE_SIZE cases.
123 */
124static inline size_t get_eb_offset_in_folio(const struct extent_buffer *eb,
125					    unsigned long offset)
126{
127	/*
128	 * 1) sectorsize == PAGE_SIZE and nodesize >= PAGE_SIZE case
129	 *    1.1) One large folio covering the whole eb
130	 *	   The eb->start is aligned to folio size, thus adding it
131	 *	   won't cause any difference.
132	 *    1.2) Several page sized folios
133	 *	   The eb->start is aligned to folio (page) size, thus
134	 *	   adding it won't cause any difference.
135	 *
136	 * 2) sectorsize < PAGE_SIZE and nodesize < PAGE_SIZE case
137	 *    In this case there would only be one page sized folio, and there
138	 *    may be several different extent buffers in the page/folio.
139	 *    We need to add eb->start to properly access the offset inside
140	 *    that eb.
141	 */
142	return offset_in_folio(eb->folios[0], offset + eb->start);
143}
144
145static inline unsigned long get_eb_folio_index(const struct extent_buffer *eb,
146					       unsigned long offset)
147{
148	/*
149	 * 1) sectorsize == PAGE_SIZE and nodesize >= PAGE_SIZE case
150	 *    1.1) One large folio covering the whole eb.
151	 *	   the folio_shift would be large enough to always make us
152	 *	   return 0 as index.
153	 *    1.2) Several page sized folios
154	 *         The folio_shift() would be PAGE_SHIFT, giving us the correct
155	 *         index.
156	 *
157	 * 2) sectorsize < PAGE_SIZE and nodesize < PAGE_SIZE case
158	 *    The folio would only be page sized, and always give us 0 as index.
159	 */
160	return offset >> folio_shift(eb->folios[0]);
161}
162
163/*
164 * Structure to record how many bytes and which ranges are set/cleared
165 */
166struct extent_changeset {
167	/* How many bytes are set/cleared in this operation */
168	u64 bytes_changed;
169
170	/* Changed ranges */
171	struct ulist range_changed;
172};
173
174static inline void extent_changeset_init(struct extent_changeset *changeset)
175{
176	changeset->bytes_changed = 0;
177	ulist_init(&changeset->range_changed);
178}
179
180static inline struct extent_changeset *extent_changeset_alloc(void)
181{
182	struct extent_changeset *ret;
183
184	ret = kmalloc(sizeof(*ret), GFP_KERNEL);
185	if (!ret)
186		return NULL;
187
188	extent_changeset_init(ret);
189	return ret;
190}
191
192static inline void extent_changeset_release(struct extent_changeset *changeset)
193{
194	if (!changeset)
195		return;
196	changeset->bytes_changed = 0;
197	ulist_release(&changeset->range_changed);
198}
199
200static inline void extent_changeset_free(struct extent_changeset *changeset)
201{
202	if (!changeset)
203		return;
204	extent_changeset_release(changeset);
205	kfree(changeset);
206}
207
 
 
 
 
 
 
 
 
 
 
 
208struct extent_map_tree;
209
210int try_release_extent_mapping(struct page *page, gfp_t mask);
 
 
 
 
 
 
 
 
 
211int try_release_extent_buffer(struct page *page);
 
 
 
 
 
 
 
 
 
 
 
 
 
212
213int btrfs_read_folio(struct file *file, struct folio *folio);
214void extent_write_locked_range(struct inode *inode, struct page *locked_page,
215			       u64 start, u64 end, struct writeback_control *wbc,
216			       bool pages_dirty);
217int extent_writepages(struct address_space *mapping,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
218		      struct writeback_control *wbc);
219int btree_write_cache_pages(struct address_space *mapping,
220			    struct writeback_control *wbc);
221void extent_readahead(struct readahead_control *rac);
222int extent_fiemap(struct btrfs_inode *inode, struct fiemap_extent_info *fieinfo,
223		  u64 start, u64 len);
224int set_page_extent_mapped(struct page *page);
225void clear_page_extent_mapped(struct page *page);
 
226
227struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
228					  u64 start, u64 owner_root, int level);
229struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
230						  u64 start, unsigned long len);
231struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
232						u64 start);
233struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src);
234struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
235					 u64 start);
236void free_extent_buffer(struct extent_buffer *eb);
237void free_extent_buffer_stale(struct extent_buffer *eb);
238#define WAIT_NONE	0
239#define WAIT_COMPLETE	1
240#define WAIT_PAGE_LOCK	2
241int read_extent_buffer_pages(struct extent_buffer *eb, int wait, int mirror_num,
242			     struct btrfs_tree_parent_check *parent_check);
 
243void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
244void btrfs_readahead_tree_block(struct btrfs_fs_info *fs_info,
245				u64 bytenr, u64 owner_root, u64 gen, int level);
246void btrfs_readahead_node_child(struct extent_buffer *node, int slot);
247
248static inline int num_extent_pages(const struct extent_buffer *eb)
249{
250	/*
251	 * For sectorsize == PAGE_SIZE case, since nodesize is always aligned to
252	 * sectorsize, it's just eb->len >> PAGE_SHIFT.
253	 *
254	 * For sectorsize < PAGE_SIZE case, we could have nodesize < PAGE_SIZE,
255	 * thus have to ensure we get at least one page.
256	 */
257	return (eb->len >> PAGE_SHIFT) ?: 1;
258}
259
260/*
261 * This can only be determined at runtime by checking eb::folios[0].
262 *
263 * As we can have either one large folio covering the whole eb
264 * (either nodesize <= PAGE_SIZE, or high order folio), or multiple
265 * single-paged folios.
266 */
267static inline int num_extent_folios(const struct extent_buffer *eb)
268{
269	if (folio_order(eb->folios[0]))
270		return 1;
271	return num_extent_pages(eb);
272}
273
274static inline int extent_buffer_uptodate(const struct extent_buffer *eb)
275{
276	return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
277}
278
279int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
280			 unsigned long start, unsigned long len);
281void read_extent_buffer(const struct extent_buffer *eb, void *dst,
282			unsigned long start,
283			unsigned long len);
284int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb,
285				       void __user *dst, unsigned long start,
286				       unsigned long len);
287void write_extent_buffer(const struct extent_buffer *eb, const void *src,
 
 
 
288			 unsigned long start, unsigned long len);
289
290static inline void write_extent_buffer_chunk_tree_uuid(
291		const struct extent_buffer *eb, const void *chunk_tree_uuid)
292{
293	write_extent_buffer(eb, chunk_tree_uuid,
294			    offsetof(struct btrfs_header, chunk_tree_uuid),
295			    BTRFS_FSID_SIZE);
296}
297
298static inline void write_extent_buffer_fsid(const struct extent_buffer *eb,
299					    const void *fsid)
300{
301	write_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
302			    BTRFS_FSID_SIZE);
303}
304
305void copy_extent_buffer_full(const struct extent_buffer *dst,
306			     const struct extent_buffer *src);
307void copy_extent_buffer(const struct extent_buffer *dst,
308			const struct extent_buffer *src,
309			unsigned long dst_offset, unsigned long src_offset,
310			unsigned long len);
311void memcpy_extent_buffer(const struct extent_buffer *dst,
312			  unsigned long dst_offset, unsigned long src_offset,
313			  unsigned long len);
314void memmove_extent_buffer(const struct extent_buffer *dst,
315			   unsigned long dst_offset, unsigned long src_offset,
316			   unsigned long len);
317void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start,
318			   unsigned long len);
319int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start,
320			   unsigned long pos);
321void extent_buffer_bitmap_set(const struct extent_buffer *eb, unsigned long start,
322			      unsigned long pos, unsigned long len);
323void extent_buffer_bitmap_clear(const struct extent_buffer *eb,
324				unsigned long start, unsigned long pos,
325				unsigned long len);
326void set_extent_buffer_dirty(struct extent_buffer *eb);
327void set_extent_buffer_uptodate(struct extent_buffer *eb);
328void clear_extent_buffer_uptodate(struct extent_buffer *eb);
 
 
 
 
 
329void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
330void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
331				  struct page *locked_page,
332				  u32 bits_to_clear, unsigned long page_ops);
333int extent_invalidate_folio(struct extent_io_tree *tree,
334			    struct folio *folio, size_t offset);
335void btrfs_clear_buffer_dirty(struct btrfs_trans_handle *trans,
336			      struct extent_buffer *buf);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
337
338int btrfs_alloc_page_array(unsigned int nr_pages, struct page **page_array,
339			   gfp_t extra_gfp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
340
 
 
 
 
 
 
 
 
 
 
 
 
 
 
341#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
342bool find_lock_delalloc_range(struct inode *inode,
343			     struct page *locked_page, u64 *start,
344			     u64 *end);
 
345#endif
346struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
347					       u64 start);
348
349#ifdef CONFIG_BTRFS_DEBUG
350void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info);
351#else
352#define btrfs_extent_buffer_leak_debug_check(fs_info)	do {} while (0)
353#endif
354
355#endif
v4.17
  1/* SPDX-License-Identifier: GPL-2.0 */
  2
  3#ifndef BTRFS_EXTENT_IO_H
  4#define BTRFS_EXTENT_IO_H
  5
  6#include <linux/rbtree.h>
  7#include <linux/refcount.h>
 
 
 
  8#include "ulist.h"
 
  9
 10/* bits for the extent state */
 11#define EXTENT_DIRTY		(1U << 0)
 12#define EXTENT_WRITEBACK	(1U << 1)
 13#define EXTENT_UPTODATE		(1U << 2)
 14#define EXTENT_LOCKED		(1U << 3)
 15#define EXTENT_NEW		(1U << 4)
 16#define EXTENT_DELALLOC		(1U << 5)
 17#define EXTENT_DEFRAG		(1U << 6)
 18#define EXTENT_BOUNDARY		(1U << 9)
 19#define EXTENT_NODATASUM	(1U << 10)
 20#define EXTENT_CLEAR_META_RESV	(1U << 11)
 21#define EXTENT_FIRST_DELALLOC	(1U << 12)
 22#define EXTENT_NEED_WAIT	(1U << 13)
 23#define EXTENT_DAMAGED		(1U << 14)
 24#define EXTENT_NORESERVE	(1U << 15)
 25#define EXTENT_QGROUP_RESERVED	(1U << 16)
 26#define EXTENT_CLEAR_DATA_RESV	(1U << 17)
 27#define EXTENT_DELALLOC_NEW	(1U << 18)
 28#define EXTENT_IOBITS		(EXTENT_LOCKED | EXTENT_WRITEBACK)
 29#define EXTENT_DO_ACCOUNTING    (EXTENT_CLEAR_META_RESV | \
 30				 EXTENT_CLEAR_DATA_RESV)
 31#define EXTENT_CTLBITS		(EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
 32
 33/*
 34 * flags for bio submission. The high bits indicate the compression
 35 * type for this bio
 36 */
 37#define EXTENT_BIO_COMPRESSED 1
 38#define EXTENT_BIO_FLAG_SHIFT 16
 39
 40/* these are bit numbers for test/set bit */
 41#define EXTENT_BUFFER_UPTODATE 0
 42#define EXTENT_BUFFER_DIRTY 2
 43#define EXTENT_BUFFER_CORRUPT 3
 44#define EXTENT_BUFFER_READAHEAD 4	/* this got triggered by readahead */
 45#define EXTENT_BUFFER_TREE_REF 5
 46#define EXTENT_BUFFER_STALE 6
 47#define EXTENT_BUFFER_WRITEBACK 7
 48#define EXTENT_BUFFER_READ_ERR 8        /* read IO error */
 49#define EXTENT_BUFFER_DUMMY 9
 50#define EXTENT_BUFFER_IN_TREE 10
 51#define EXTENT_BUFFER_WRITE_ERR 11    /* write IO error */
 
 52
 53/* these are flags for __process_pages_contig */
 54#define PAGE_UNLOCK		(1 << 0)
 55#define PAGE_CLEAR_DIRTY	(1 << 1)
 56#define PAGE_SET_WRITEBACK	(1 << 2)
 57#define PAGE_END_WRITEBACK	(1 << 3)
 58#define PAGE_SET_PRIVATE2	(1 << 4)
 59#define PAGE_SET_ERROR		(1 << 5)
 60#define PAGE_LOCK		(1 << 6)
 61
 62/*
 63 * page->private values.  Every page that is controlled by the extent
 64 * map has page->private set to one.
 65 */
 66#define EXTENT_PAGE_PRIVATE 1
 67
 68/*
 69 * The extent buffer bitmap operations are done with byte granularity instead of
 70 * word granularity for two reasons:
 71 * 1. The bitmaps must be little-endian on disk.
 72 * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
 73 *    single word in a bitmap may straddle two pages in the extent buffer.
 74 */
 75#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
 76#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
 77#define BITMAP_FIRST_BYTE_MASK(start) \
 78	((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
 79#define BITMAP_LAST_BYTE_MASK(nbits) \
 80	(BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
 81
 82static inline int le_test_bit(int nr, const u8 *addr)
 83{
 84	return 1U & (addr[BIT_BYTE(nr)] >> (nr & (BITS_PER_BYTE-1)));
 85}
 86
 87void le_bitmap_set(u8 *map, unsigned int start, int len);
 88void le_bitmap_clear(u8 *map, unsigned int start, int len);
 89
 90struct extent_state;
 91struct btrfs_root;
 92struct btrfs_inode;
 93struct btrfs_io_bio;
 94struct io_failure_record;
 95
 96typedef	blk_status_t (extent_submit_bio_hook_t)(void *private_data, struct bio *bio,
 97				       int mirror_num, unsigned long bio_flags,
 98				       u64 bio_offset);
 99
100typedef blk_status_t (extent_submit_bio_start_t)(void *private_data,
101		struct bio *bio, u64 bio_offset);
102
103typedef blk_status_t (extent_submit_bio_done_t)(void *private_data,
104		struct bio *bio, int mirror_num);
105
106struct extent_io_ops {
107	/*
108	 * The following callbacks must be allways defined, the function
109	 * pointer will be called unconditionally.
110	 */
111	extent_submit_bio_hook_t *submit_bio_hook;
112	int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
113				    struct page *page, u64 start, u64 end,
114				    int mirror);
115	int (*merge_bio_hook)(struct page *page, unsigned long offset,
116			      size_t size, struct bio *bio,
117			      unsigned long bio_flags);
118	int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
119	struct btrfs_fs_info *(*tree_fs_info)(void *private_data);
120	void (*set_range_writeback)(void *private_data, u64 start, u64 end);
121
122	/*
123	 * Optional hooks, called if the pointer is not NULL
124	 */
125	int (*fill_delalloc)(void *private_data, struct page *locked_page,
126			     u64 start, u64 end, int *page_started,
127			     unsigned long *nr_written,
128			     struct writeback_control *wbc);
129
130	int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
131	void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
132				      struct extent_state *state, int uptodate);
133	void (*set_bit_hook)(void *private_data, struct extent_state *state,
134			     unsigned *bits);
135	void (*clear_bit_hook)(void *private_data,
136			struct extent_state *state,
137			unsigned *bits);
138	void (*merge_extent_hook)(void *private_data,
139				  struct extent_state *new,
140				  struct extent_state *other);
141	void (*split_extent_hook)(void *private_data,
142				  struct extent_state *orig, u64 split);
143	void (*check_extent_io_range)(void *private_data, const char *caller,
144				      u64 start, u64 end);
145};
146
147struct extent_io_tree {
148	struct rb_root state;
149	void *private_data;
150	u64 dirty_bytes;
151	int track_uptodate;
152	spinlock_t lock;
153	const struct extent_io_ops *ops;
154};
155
156struct extent_state {
157	u64 start;
158	u64 end; /* inclusive */
159	struct rb_node rb_node;
160
161	/* ADD NEW ELEMENTS AFTER THIS */
162	wait_queue_head_t wq;
163	refcount_t refs;
164	unsigned state;
165
166	struct io_failure_record *failrec;
167
168#ifdef CONFIG_BTRFS_DEBUG
169	struct list_head leak_list;
170#endif
171};
172
173#define INLINE_EXTENT_BUFFER_PAGES 16
174#define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE)
175struct extent_buffer {
176	u64 start;
177	unsigned long len;
178	unsigned long bflags;
179	struct btrfs_fs_info *fs_info;
 
 
 
 
 
 
 
180	spinlock_t refs_lock;
181	atomic_t refs;
182	atomic_t io_pages;
183	int read_mirror;
 
 
184	struct rcu_head rcu_head;
185	pid_t lock_owner;
186
187	/* count of read lock holders on the extent buffer */
188	atomic_t write_locks;
189	atomic_t read_locks;
190	atomic_t blocking_writers;
191	atomic_t blocking_readers;
192	atomic_t spinning_readers;
193	atomic_t spinning_writers;
194	short lock_nested;
195	/* >= 0 if eb belongs to a log tree, -1 otherwise */
196	short log_index;
197
198	/* protects write locks */
199	rwlock_t lock;
200
201	/* readers use lock_wq while they wait for the write
202	 * lock holders to unlock
203	 */
204	wait_queue_head_t write_lock_wq;
205
206	/* writers use read_lock_wq while they wait for readers
207	 * to unlock
208	 */
209	wait_queue_head_t read_lock_wq;
210	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
211#ifdef CONFIG_BTRFS_DEBUG
212	struct list_head leak_list;
 
213#endif
214};
215
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
216/*
217 * Structure to record how many bytes and which ranges are set/cleared
218 */
219struct extent_changeset {
220	/* How many bytes are set/cleared in this operation */
221	unsigned int bytes_changed;
222
223	/* Changed ranges */
224	struct ulist range_changed;
225};
226
227static inline void extent_changeset_init(struct extent_changeset *changeset)
228{
229	changeset->bytes_changed = 0;
230	ulist_init(&changeset->range_changed);
231}
232
233static inline struct extent_changeset *extent_changeset_alloc(void)
234{
235	struct extent_changeset *ret;
236
237	ret = kmalloc(sizeof(*ret), GFP_KERNEL);
238	if (!ret)
239		return NULL;
240
241	extent_changeset_init(ret);
242	return ret;
243}
244
245static inline void extent_changeset_release(struct extent_changeset *changeset)
246{
247	if (!changeset)
248		return;
249	changeset->bytes_changed = 0;
250	ulist_release(&changeset->range_changed);
251}
252
253static inline void extent_changeset_free(struct extent_changeset *changeset)
254{
255	if (!changeset)
256		return;
257	extent_changeset_release(changeset);
258	kfree(changeset);
259}
260
261static inline void extent_set_compress_type(unsigned long *bio_flags,
262					    int compress_type)
263{
264	*bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
265}
266
267static inline int extent_compress_type(unsigned long bio_flags)
268{
269	return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
270}
271
272struct extent_map_tree;
273
274typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode,
275					  struct page *page,
276					  size_t pg_offset,
277					  u64 start, u64 len,
278					  int create);
279
280void extent_io_tree_init(struct extent_io_tree *tree, void *private_data);
281int try_release_extent_mapping(struct extent_map_tree *map,
282			       struct extent_io_tree *tree, struct page *page,
283			       gfp_t mask);
284int try_release_extent_buffer(struct page *page);
285int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
286		     struct extent_state **cached);
287
288static inline int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
289{
290	return lock_extent_bits(tree, start, end, NULL);
291}
292
293int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
294int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
295			  get_extent_t *get_extent, int mirror_num);
296int __init extent_io_init(void);
297void __cold extent_io_exit(void);
298
299u64 count_range_bits(struct extent_io_tree *tree,
300		     u64 *start, u64 search_end,
301		     u64 max_bytes, unsigned bits, int contig);
302
303void free_extent_state(struct extent_state *state);
304int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
305		   unsigned bits, int filled,
306		   struct extent_state *cached_state);
307int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
308		unsigned bits, struct extent_changeset *changeset);
309int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
310		     unsigned bits, int wake, int delete,
311		     struct extent_state **cached);
312int __clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
313		     unsigned bits, int wake, int delete,
314		     struct extent_state **cached, gfp_t mask,
315		     struct extent_changeset *changeset);
316
317static inline int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
318{
319	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL);
320}
321
322static inline int unlock_extent_cached(struct extent_io_tree *tree, u64 start,
323		u64 end, struct extent_state **cached)
324{
325	return __clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
326				GFP_NOFS, NULL);
327}
328
329static inline int unlock_extent_cached_atomic(struct extent_io_tree *tree,
330		u64 start, u64 end, struct extent_state **cached)
331{
332	return __clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
333				GFP_ATOMIC, NULL);
334}
335
336static inline int clear_extent_bits(struct extent_io_tree *tree, u64 start,
337		u64 end, unsigned bits)
338{
339	int wake = 0;
340
341	if (bits & EXTENT_LOCKED)
342		wake = 1;
343
344	return clear_extent_bit(tree, start, end, bits, wake, 0, NULL);
345}
346
347int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
348			   unsigned bits, struct extent_changeset *changeset);
349int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
350		   unsigned bits, u64 *failed_start,
351		   struct extent_state **cached_state, gfp_t mask);
352
353static inline int set_extent_bits(struct extent_io_tree *tree, u64 start,
354		u64 end, unsigned bits)
355{
356	return set_extent_bit(tree, start, end, bits, NULL, NULL, GFP_NOFS);
357}
358
359static inline int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
360		u64 end, struct extent_state **cached_state)
361{
362	return __clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
363				cached_state, GFP_NOFS, NULL);
364}
365
366static inline int set_extent_dirty(struct extent_io_tree *tree, u64 start,
367		u64 end, gfp_t mask)
368{
369	return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
370			      NULL, mask);
371}
372
373static inline int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
374		u64 end)
375{
376	return clear_extent_bit(tree, start, end,
377				EXTENT_DIRTY | EXTENT_DELALLOC |
378				EXTENT_DO_ACCOUNTING, 0, 0, NULL);
379}
380
381int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
382		       unsigned bits, unsigned clear_bits,
383		       struct extent_state **cached_state);
384
385static inline int set_extent_delalloc(struct extent_io_tree *tree, u64 start,
386				      u64 end, unsigned int extra_bits,
387				      struct extent_state **cached_state)
388{
389	return set_extent_bit(tree, start, end,
390			      EXTENT_DELALLOC | EXTENT_UPTODATE | extra_bits,
391			      NULL, cached_state, GFP_NOFS);
392}
393
394static inline int set_extent_defrag(struct extent_io_tree *tree, u64 start,
395		u64 end, struct extent_state **cached_state)
396{
397	return set_extent_bit(tree, start, end,
398			      EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
399			      NULL, cached_state, GFP_NOFS);
400}
401
402static inline int set_extent_new(struct extent_io_tree *tree, u64 start,
403		u64 end)
404{
405	return set_extent_bit(tree, start, end, EXTENT_NEW, NULL, NULL,
406			GFP_NOFS);
407}
408
409static inline int set_extent_uptodate(struct extent_io_tree *tree, u64 start,
410		u64 end, struct extent_state **cached_state, gfp_t mask)
411{
412	return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
413			      cached_state, mask);
414}
415
416int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
417			  u64 *start_ret, u64 *end_ret, unsigned bits,
418			  struct extent_state **cached_state);
419int extent_invalidatepage(struct extent_io_tree *tree,
420			  struct page *page, unsigned long offset);
421int extent_write_full_page(struct page *page, struct writeback_control *wbc);
422int extent_write_locked_range(struct inode *inode, u64 start, u64 end,
423			      int mode);
424int extent_writepages(struct extent_io_tree *tree,
425		      struct address_space *mapping,
426		      struct writeback_control *wbc);
427int btree_write_cache_pages(struct address_space *mapping,
428			    struct writeback_control *wbc);
429int extent_readpages(struct extent_io_tree *tree,
430		     struct address_space *mapping,
431		     struct list_head *pages, unsigned nr_pages);
432int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
433		__u64 start, __u64 len);
434void set_page_extent_mapped(struct page *page);
435
436struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
437					  u64 start);
438struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
439						  u64 start, unsigned long len);
440struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
441						u64 start);
442struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
443struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
444					 u64 start);
445void free_extent_buffer(struct extent_buffer *eb);
446void free_extent_buffer_stale(struct extent_buffer *eb);
447#define WAIT_NONE	0
448#define WAIT_COMPLETE	1
449#define WAIT_PAGE_LOCK	2
450int read_extent_buffer_pages(struct extent_io_tree *tree,
451			     struct extent_buffer *eb, int wait,
452			     int mirror_num);
453void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
 
 
 
454
455static inline unsigned long num_extent_pages(u64 start, u64 len)
456{
457	return ((start + len + PAGE_SIZE - 1) >> PAGE_SHIFT) -
458		(start >> PAGE_SHIFT);
 
 
 
 
 
 
459}
460
461static inline void extent_buffer_get(struct extent_buffer *eb)
 
 
 
 
 
 
 
462{
463	atomic_inc(&eb->refs);
 
 
464}
465
466static inline int extent_buffer_uptodate(struct extent_buffer *eb)
467{
468	return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
469}
470
471int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
472			 unsigned long start, unsigned long len);
473void read_extent_buffer(const struct extent_buffer *eb, void *dst,
474			unsigned long start,
475			unsigned long len);
476int read_extent_buffer_to_user(const struct extent_buffer *eb,
477			       void __user *dst, unsigned long start,
478			       unsigned long len);
479void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src);
480void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
481		const void *src);
482void write_extent_buffer(struct extent_buffer *eb, const void *src,
483			 unsigned long start, unsigned long len);
484void copy_extent_buffer_full(struct extent_buffer *dst,
485			     struct extent_buffer *src);
486void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
487			unsigned long dst_offset, unsigned long src_offset,
488			unsigned long len);
489void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
490			   unsigned long src_offset, unsigned long len);
491void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
492			   unsigned long src_offset, unsigned long len);
493void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start,
 
 
494			   unsigned long len);
495int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
496			   unsigned long pos);
497void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
498			      unsigned long pos, unsigned long len);
499void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
500				unsigned long pos, unsigned long len);
501void clear_extent_buffer_dirty(struct extent_buffer *eb);
502int set_extent_buffer_dirty(struct extent_buffer *eb);
503void set_extent_buffer_uptodate(struct extent_buffer *eb);
504void clear_extent_buffer_uptodate(struct extent_buffer *eb);
505int extent_buffer_under_io(struct extent_buffer *eb);
506int map_private_extent_buffer(const struct extent_buffer *eb,
507			      unsigned long offset, unsigned long min_len,
508			      char **map, unsigned long *map_start,
509			      unsigned long *map_len);
510void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
511void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
512void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
513				 u64 delalloc_end, struct page *locked_page,
514				 unsigned bits_to_clear,
515				 unsigned long page_ops);
516struct bio *btrfs_bio_alloc(struct block_device *bdev, u64 first_byte);
517struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs);
518struct bio *btrfs_bio_clone(struct bio *bio);
519struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size);
520
521struct btrfs_fs_info;
522struct btrfs_inode;
523
524int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
525		      u64 length, u64 logical, struct page *page,
526		      unsigned int pg_offset, int mirror_num);
527int clean_io_failure(struct btrfs_fs_info *fs_info,
528		     struct extent_io_tree *failure_tree,
529		     struct extent_io_tree *io_tree, u64 start,
530		     struct page *page, u64 ino, unsigned int pg_offset);
531void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
532int repair_eb_io_failure(struct btrfs_fs_info *fs_info,
533			 struct extent_buffer *eb, int mirror_num);
534
535/*
536 * When IO fails, either with EIO or csum verification fails, we
537 * try other mirrors that might have a good copy of the data.  This
538 * io_failure_record is used to record state as we go through all the
539 * mirrors.  If another mirror has good data, the page is set up to date
540 * and things continue.  If a good mirror can't be found, the original
541 * bio end_io callback is called to indicate things have failed.
542 */
543struct io_failure_record {
544	struct page *page;
545	u64 start;
546	u64 len;
547	u64 logical;
548	unsigned long bio_flags;
549	int this_mirror;
550	int failed_mirror;
551	int in_validation;
552};
553
554
555void btrfs_free_io_failure_record(struct btrfs_inode *inode, u64 start,
556		u64 end);
557int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
558				struct io_failure_record **failrec_ret);
559bool btrfs_check_repairable(struct inode *inode, unsigned failed_bio_pages,
560			    struct io_failure_record *failrec, int fail_mirror);
561struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
562				    struct io_failure_record *failrec,
563				    struct page *page, int pg_offset, int icsum,
564				    bio_end_io_t *endio_func, void *data);
565int free_io_failure(struct extent_io_tree *failure_tree,
566		    struct extent_io_tree *io_tree,
567		    struct io_failure_record *rec);
568#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
569noinline u64 find_lock_delalloc_range(struct inode *inode,
570				      struct extent_io_tree *tree,
571				      struct page *locked_page, u64 *start,
572				      u64 *end, u64 max_bytes);
573#endif
574struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
575					       u64 start);
 
 
 
 
 
 
576
577#endif