fs/btrfs/extent-io.h

   1 // SPDX-License-Identifier: GPL-2.0+
   2
   3 /*
   4  * Crossported from btrfs-progs/extent_io.h
   5  *
   6  * Modification includes:
   7  * - extent_buffer:data
   8  *   Use pointer to provide better alignment.
   9  * - Remove max_cache_size related interfaces
  10  *   Includes free_extent_buffer_nocache()
  11  *   As we don't cache eb in U-Boot.
  12  * - Include headers
  13  *
  14  * Write related functions are kept as we still need to modify dummy extent
  15  * buffers even in RO environment.
  16  */
  17 #ifndef __BTRFS_EXTENT_IO_H__
  18 #define __BTRFS_EXTENT_IO_H__
  19
  20 #include <linux/types.h>
  21 #include <linux/list.h>
  22 #include <linux/err.h>
  23 #include <linux/bitops.h>
  24 #include <fs_internal.h>
  25 #include "extent-cache.h"
  26
  27 #define EXTENT_DIRTY            (1U << 0)
  28 #define EXTENT_WRITEBACK        (1U << 1)
  29 #define EXTENT_UPTODATE         (1U << 2)
  30 #define EXTENT_LOCKED           (1U << 3)
  31 #define EXTENT_NEW              (1U << 4)
  32 #define EXTENT_DELALLOC         (1U << 5)
  33 #define EXTENT_DEFRAG           (1U << 6)
  34 #define EXTENT_DEFRAG_DONE      (1U << 7)
  35 #define EXTENT_BUFFER_FILLED    (1U << 8)
  36 #define EXTENT_CSUM             (1U << 9)
  37 #define EXTENT_BAD_TRANSID      (1U << 10)
  38 #define EXTENT_BUFFER_DUMMY     (1U << 11)
  39 #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
  40
  41 #define BLOCK_GROUP_DATA        (1U << 1)
  42 #define BLOCK_GROUP_METADATA    (1U << 2)
  43 #define BLOCK_GROUP_SYSTEM      (1U << 4)
  44
  45 /*
  46  * The extent buffer bitmap operations are done with byte granularity instead of
  47  * word granularity for two reasons:
  48  * 1. The bitmaps must be little-endian on disk.
  49  * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
  50  *    single word in a bitmap may straddle two pages in the extent buffer.
  51  */
  52 #define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
  53 #define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
  54 #define BITMAP_FIRST_BYTE_MASK(start) \
  55         ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
  56 #define BITMAP_LAST_BYTE_MASK(nbits) \
  57         (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
  58
  59 static inline int le_test_bit(int nr, const u8 *addr)
  60 {
  61         return 1U & (addr[BIT_BYTE(nr)] >> (nr & (BITS_PER_BYTE-1)));
  62 }
  63
  64 struct btrfs_fs_info;
  65
  66 struct extent_io_tree {
  67         struct cache_tree state;
  68         struct cache_tree cache;
  69         u64 cache_size;
  70 };
  71
  72 struct extent_state {
  73         struct cache_extent cache_node;
  74         u64 start;
  75         u64 end;
  76         int refs;
  77         unsigned long state;
  78         u64 xprivate;
  79 };
  80
  81 struct extent_buffer {
  82         struct cache_extent cache_node;
  83         u64 start;
  84         u32 len;
  85         int refs;
  86         u32 flags;
  87         struct btrfs_fs_info *fs_info;
  88         char *data;
  89 };
  90
  91 static inline void extent_buffer_get(struct extent_buffer *eb)
  92 {
  93         eb->refs++;
  94 }
  95
  96 void extent_io_tree_init(struct extent_io_tree *tree);
  97 void extent_io_tree_cleanup(struct extent_io_tree *tree);
  98 int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits);
  99 int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int bits);
 100 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
 101                           u64 *start_ret, u64 *end_ret, int bits);
 102 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
 103                    int bits, int filled);
 104 int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end);
 105 int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end);
 106 static inline int set_extent_buffer_uptodate(struct extent_buffer *eb)
 107 {
 108         eb->flags |= EXTENT_UPTODATE;
 109         return 0;
 110 }
 111
 112 static inline int clear_extent_buffer_uptodate(struct extent_buffer *eb)
 113 {
 114         eb->flags &= ~EXTENT_UPTODATE;
 115         return 0;
 116 }
 117
 118 static inline int extent_buffer_uptodate(struct extent_buffer *eb)
 119 {
 120         if (!eb || IS_ERR(eb))
 121                 return 0;
 122         if (eb->flags & EXTENT_UPTODATE)
 123                 return 1;
 124         return 0;
 125 }
 126
 127 int set_state_private(struct extent_io_tree *tree, u64 start, u64 xprivate);
 128 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *xprivate);
 129 struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
 130                                          u64 bytenr, u32 blocksize);
 131 struct extent_buffer *find_first_extent_buffer(struct extent_io_tree *tree,
 132                                                u64 start);
 133 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
 134                                           u64 bytenr, u32 blocksize);
 135 struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
 136 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
 137                                                 u64 bytenr, u32 blocksize);
 138 void free_extent_buffer(struct extent_buffer *eb);
 139 int read_extent_from_disk(struct blk_desc *desc, struct disk_partition *part,
 140                           u64 physical, struct extent_buffer *eb,
 141                           unsigned long offset, unsigned long len);
 142 int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
 143                          unsigned long start, unsigned long len);
 144 void read_extent_buffer(const struct extent_buffer *eb, void *dst,
 145                         unsigned long start, unsigned long len);
 146 void write_extent_buffer(struct extent_buffer *eb, const void *src,
 147                          unsigned long start, unsigned long len);
 148 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
 149                         unsigned long dst_offset, unsigned long src_offset,
 150                         unsigned long len);
 151 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 152                            unsigned long src_offset, unsigned long len);
 153 void memset_extent_buffer(struct extent_buffer *eb, char c,
 154                           unsigned long start, unsigned long len);
 155 int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
 156                            unsigned long nr);
 157 int set_extent_buffer_dirty(struct extent_buffer *eb);
 158 int clear_extent_buffer_dirty(struct extent_buffer *eb);
 159 void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
 160                                 unsigned long pos, unsigned long len);
 161 void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
 162                               unsigned long pos, unsigned long len);
 163
 164 #endif