switch-from-blkno-to-disk-offset

   1 iomap: Switch from blkno to disk offset
   2
   3 From: Andreas Gruenbacher <agruenba@redhat.com>
   4
   5 Replace iomap->blkno, the sector number, with iomap->addr, the disk
   6 offset in bytes.  For invalid disk offsets, use the special value
   7 IOMAP_NULL_ADDR instead of IOMAP_NULL_BLOCK.
   8
   9 This allows to use iomap for mappings which are not block aligned, such
  10 as inline data on ext4.
  11
  12 Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
  13 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  14 Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>  # iomap, xfs
  15 Reviewed-by: Jan Kara <jack@suse.cz>
  16 ---
  17  fs/buffer.c           |  4 ++--
  18  fs/dax.c              |  2 +-
  19  fs/ext2/inode.c       |  4 ++--
  20  fs/ext4/inode.c       |  4 ++--
  21  fs/iomap.c            | 11 +++++------
  22  fs/nfsd/blocklayout.c |  4 ++--
  23  fs/xfs/xfs_iomap.c    |  6 +++---
  24  include/linux/iomap.h | 10 +++++-----
  25  8 files changed, 22 insertions(+), 23 deletions(-)
  26
  27 diff --git a/fs/buffer.c b/fs/buffer.c
  28 index 170df856bdb9..bd4d0923cdce 100644
  29 --- a/fs/buffer.c
  30 +++ b/fs/buffer.c
  31 @@ -1978,8 +1978,8 @@ iomap_to_bh(struct inode *inode, sector_t block, struct buffer_head *bh,
  32         case IOMAP_MAPPED:
  33                 if (offset >= i_size_read(inode))
  34                         set_buffer_new(bh);
  35 -               bh->b_blocknr = (iomap->blkno >> (inode->i_blkbits - 9)) +
  36 -                               ((offset - iomap->offset) >> inode->i_blkbits);
  37 +               bh->b_blocknr = (iomap->addr + offset - iomap->offset) >>
  38 +                               inode->i_blkbits;
  39                 set_buffer_mapped(bh);
  40                 break;
  41         }
  42 diff --git a/fs/dax.c b/fs/dax.c
  43 index 6afcacb3a87b..feccb4ec45d2 100644
  44 --- a/fs/dax.c
  45 +++ b/fs/dax.c
  46 @@ -938,7 +938,7 @@ EXPORT_SYMBOL_GPL(__dax_zero_page_range);
  47
  48  static sector_t dax_iomap_sector(struct iomap *iomap, loff_t pos)
  49  {
  50 -       return iomap->blkno + (((pos & PAGE_MASK) - iomap->offset) >> 9);
  51 +       return (iomap->addr + (pos & PAGE_MASK) - iomap->offset) >> 9;
  52  }
  53
  54  static loff_t
  55 diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
  56 index 4dca6f348714..1b8fc73de4a1 100644
  57 --- a/fs/ext2/inode.c
  58 +++ b/fs/ext2/inode.c
  59 @@ -820,11 +820,11 @@ static int ext2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
  60
  61         if (ret == 0) {
  62                 iomap->type = IOMAP_HOLE;
  63 -               iomap->blkno = IOMAP_NULL_BLOCK;
  64 +               iomap->addr = IOMAP_NULL_ADDR;
  65                 iomap->length = 1 << blkbits;
  66         } else {
  67                 iomap->type = IOMAP_MAPPED;
  68 -               iomap->blkno = (sector_t)bno << (blkbits - 9);
  69 +               iomap->addr = (u64)bno << blkbits;
  70                 iomap->length = (u64)ret << blkbits;
  71                 iomap->flags |= IOMAP_F_MERGED;
  72         }
  73 diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
  74 index 31db875bc7a1..d9e633c12aae 100644
  75 --- a/fs/ext4/inode.c
  76 +++ b/fs/ext4/inode.c
  77 @@ -3472,7 +3472,7 @@ static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
  78
  79         if (ret == 0) {
  80                 iomap->type = IOMAP_HOLE;
  81 -               iomap->blkno = IOMAP_NULL_BLOCK;
  82 +               iomap->addr = IOMAP_NULL_ADDR;
  83                 iomap->length = (u64)map.m_len << blkbits;
  84         } else {
  85                 if (map.m_flags & EXT4_MAP_MAPPED) {
  86 @@ -3483,7 +3483,7 @@ static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
  87                         WARN_ON_ONCE(1);
  88                         return -EIO;
  89                 }
  90 -               iomap->blkno = (sector_t)map.m_pblk << (blkbits - 9);
  91 +               iomap->addr = (u64)map.m_pblk << blkbits;
  92                 iomap->length = (u64)map.m_len << blkbits;
  93         }
  94
  95 diff --git a/fs/iomap.c b/fs/iomap.c
  96 index 269b24a01f32..622c731c57a0 100644
  97 --- a/fs/iomap.c
  98 +++ b/fs/iomap.c
  99 @@ -350,8 +350,8 @@ static int iomap_zero(struct inode *inode, loff_t pos, unsigned offset,
 100  static int iomap_dax_zero(loff_t pos, unsigned offset, unsigned bytes,
 101                 struct iomap *iomap)
 102  {
 103 -       sector_t sector = iomap->blkno +
 104 -               (((pos & ~(PAGE_SIZE - 1)) - iomap->offset) >> 9);
 105 +       sector_t sector = (iomap->addr +
 106 +                          (pos & PAGE_MASK) - iomap->offset) >> 9;
 107
 108         return __dax_zero_page_range(iomap->bdev, iomap->dax_dev, sector,
 109                         offset, bytes);
 110 @@ -512,9 +512,8 @@ static int iomap_to_fiemap(struct fiemap_extent_info *fi,
 111                 flags |= FIEMAP_EXTENT_SHARED;
 112
 113         return fiemap_fill_next_extent(fi, iomap->offset,
 114 -                       iomap->blkno != IOMAP_NULL_BLOCK ? iomap->blkno << 9: 0,
 115 +                       iomap->addr != IOMAP_NULL_ADDR ? iomap->addr : 0,
 116                         iomap->length, flags);
 117 -
 118  }
 119
 120  static loff_t
 121 @@ -807,7 +806,7 @@ iomap_dio_zero(struct iomap_dio *dio, struct iomap *iomap, loff_t pos,
 122         bio = bio_alloc(GFP_KERNEL, 1);
 123         bio_set_dev(bio, iomap->bdev);
 124         bio->bi_iter.bi_sector =
 125 -               iomap->blkno + ((pos - iomap->offset) >> 9);
 126 +               (iomap->addr + pos - iomap->offset) >> 9;
 127         bio->bi_private = dio;
 128         bio->bi_end_io = iomap_dio_bio_end_io;
 129
 130 @@ -886,7 +885,7 @@ iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length,
 131                 bio = bio_alloc(GFP_KERNEL, nr_pages);
 132                 bio_set_dev(bio, iomap->bdev);
 133                 bio->bi_iter.bi_sector =
 134 -                       iomap->blkno + ((pos - iomap->offset) >> 9);
 135 +                       (iomap->addr + pos - iomap->offset) >> 9;
 136                 bio->bi_write_hint = dio->iocb->ki_hint;
 137                 bio->bi_private = dio;
 138                 bio->bi_end_io = iomap_dio_bio_end_io;
 139 diff --git a/fs/nfsd/blocklayout.c b/fs/nfsd/blocklayout.c
 140 index c862c2489df0..2d1d37b27dc7 100644
 141 --- a/fs/nfsd/blocklayout.c
 142 +++ b/fs/nfsd/blocklayout.c
 143 @@ -65,7 +65,7 @@ nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
 144                         bex->es = PNFS_BLOCK_READ_DATA;
 145                 else
 146                         bex->es = PNFS_BLOCK_READWRITE_DATA;
 147 -               bex->soff = (iomap.blkno << 9);
 148 +               bex->soff = iomap.addr;
 149                 break;
 150         case IOMAP_UNWRITTEN:
 151                 if (seg->iomode & IOMODE_RW) {
 152 @@ -78,7 +78,7 @@ nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
 153                         }
 154
 155                         bex->es = PNFS_BLOCK_INVALID_DATA;
 156 -                       bex->soff = (iomap.blkno << 9);
 157 +                       bex->soff = iomap.addr;
 158                         break;
 159                 }
 160                 /*FALLTHRU*/
 161 diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
 162 index a1909bc064e9..ac22a5c00079 100644
 163 --- a/fs/xfs/xfs_iomap.c
 164 +++ b/fs/xfs/xfs_iomap.c
 165 @@ -54,13 +54,13 @@ xfs_bmbt_to_iomap(
 166         struct xfs_mount        *mp = ip->i_mount;
 167
 168         if (imap->br_startblock == HOLESTARTBLOCK) {
 169 -               iomap->blkno = IOMAP_NULL_BLOCK;
 170 +               iomap->addr = IOMAP_NULL_ADDR;
 171                 iomap->type = IOMAP_HOLE;
 172         } else if (imap->br_startblock == DELAYSTARTBLOCK) {
 173 -               iomap->blkno = IOMAP_NULL_BLOCK;
 174 +               iomap->addr = IOMAP_NULL_ADDR;
 175                 iomap->type = IOMAP_DELALLOC;
 176         } else {
 177 -               iomap->blkno = xfs_fsb_to_db(ip, imap->br_startblock);
 178 +               iomap->addr = BBTOB(xfs_fsb_to_db(ip, imap->br_startblock));
 179                 if (imap->br_state == XFS_EXT_UNWRITTEN)
 180                         iomap->type = IOMAP_UNWRITTEN;
 181                 else
 182 diff --git a/include/linux/iomap.h b/include/linux/iomap.h
 183 index f64dc6ce5161..7b8a615fa021 100644
 184 --- a/include/linux/iomap.h
 185 +++ b/include/linux/iomap.h
 186 @@ -15,8 +15,8 @@ struct vm_fault;
 187   */
 188  #define IOMAP_HOLE     0x01    /* no blocks allocated, need allocation */
 189  #define IOMAP_DELALLOC 0x02    /* delayed allocation blocks */
 190 -#define IOMAP_MAPPED   0x03    /* blocks allocated @blkno */
 191 -#define IOMAP_UNWRITTEN        0x04    /* blocks allocated @blkno in unwritten state */
 192 +#define IOMAP_MAPPED   0x03    /* blocks allocated at @addr */
 193 +#define IOMAP_UNWRITTEN        0x04    /* blocks allocated at @addr in unwritten state */
 194
 195  /*
 196   * Flags for all iomap mappings:
 197 @@ -30,12 +30,12 @@ struct vm_fault;
 198  #define IOMAP_F_SHARED 0x20    /* block shared with another file */
 199
 200  /*
 201 - * Magic value for blkno:
 202 + * Magic value for addr:
 203   */
 204 -#define IOMAP_NULL_BLOCK -1LL  /* blkno is not valid */
 205 +#define IOMAP_NULL_ADDR -1ULL  /* addr is not valid */
 206
 207  struct iomap {
 208 -       sector_t                blkno;  /* 1st sector of mapping, 512b units */
 209 +       u64                     addr; /* disk offset of mapping, bytes */
 210         loff_t                  offset; /* file offset of mapping, bytes */
 211         u64                     length; /* length of mapping, bytes */
 212         u16                     type;   /* type of mapping */
 213 --
 214 2.13.3
 215
 216