add-indirection-to-metadata-block-read-paths

   1 Add indirection to metadata read paths
   2
   3 From: Abutalib Aghayev <agayev@cs.cmu.edu>
   4
   5 Change all metadata block reads to use jmap-aware function that first looks
   6 up the metadata block in the jmap.  If lookup is successful, the function
   7 reads the corresponding log block from the journal and copies it to the
   8 metadata block buffer head.  Otherwise, it reads the metadata block from
   9 the file system, just like standard jmap-unaware function.
  10
  11 Signed-off-by: Abutalib Aghayev <agayev@cs.cmu.edu>
  12
  13 ---
  14  fs/ext4/extents.c     |  3 ++-
  15  fs/ext4/ialloc.c      |  5 ++++-
  16  fs/ext4/indirect.c    |  3 ++-
  17  fs/ext4/inode.c       | 14 ++++++++++----
  18  fs/ext4/move_extent.c |  3 ++-
  19  fs/ext4/namei.c       |  8 +++++---
  20  fs/ext4/resize.c      |  4 +++-
  21  fs/jbd2/jmap.c        | 17 ++++++++++-------
  22  8 files changed, 38 insertions(+), 19 deletions(-)
  23
  24 diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
  25 index 2a97dff87b96..342e4f0c23db 100644
  26 --- a/fs/ext4/extents.c
  27 +++ b/fs/ext4/extents.c
  28 @@ -517,6 +517,7 @@ __read_extent_tree_block(const char *function, unsigned int line,
  29  {
  30         struct buffer_head              *bh;
  31         int                             err;
  32 +       journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
  33
  34         bh = sb_getblk_gfp(inode->i_sb, pblk, __GFP_MOVABLE | GFP_NOFS);
  35         if (unlikely(!bh))
  36 @@ -524,7 +525,7 @@ __read_extent_tree_block(const char *function, unsigned int line,
  37
  38         if (!bh_uptodate_or_lock(bh)) {
  39                 trace_ext4_ext_load_extent(inode, pblk, _RET_IP_);
  40 -               err = bh_submit_read(bh);
  41 +               err = jbd2_bh_submit_read(journal, bh, __func__);
  42                 if (err < 0)
  43                         goto errout;
  44         }
  45 diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
  46 index b14bae2598bc..a095b8c1465a 100644
  47 --- a/fs/ext4/ialloc.c
  48 +++ b/fs/ext4/ialloc.c
  49 @@ -14,6 +14,7 @@
  50
  51  #include <linux/time.h>
  52  #include <linux/fs.h>
  53 +#include <linux/jbd2.h>
  54  #include <linux/stat.h>
  55  #include <linux/string.h>
  56  #include <linux/quotaops.h>
  57 @@ -160,6 +161,7 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
  58         struct buffer_head *bh = NULL;
  59         ext4_fsblk_t bitmap_blk;
  60         int err;
  61 +       journal_t *journal = EXT4_SB(sb)->s_journal;
  62
  63         desc = ext4_get_group_desc(sb, block_group, NULL);
  64         if (!desc)
  65 @@ -214,7 +216,8 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
  66         trace_ext4_load_inode_bitmap(sb, block_group);
  67         bh->b_end_io = ext4_end_bitmap_read;
  68         get_bh(bh);
  69 -       submit_bh(REQ_OP_READ, REQ_META | REQ_PRIO, bh);
  70 +       jbd2_submit_bh(journal, REQ_OP_READ, REQ_META | REQ_PRIO, bh, __func__);
  71 +
  72         wait_on_buffer(bh);
  73         if (!buffer_uptodate(bh)) {
  74                 put_bh(bh);
  75 diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
  76 index bc15c2c17633..21531ef4a182 100644
  77 --- a/fs/ext4/indirect.c
  78 +++ b/fs/ext4/indirect.c
  79 @@ -145,6 +145,7 @@ static Indirect *ext4_get_branch(struct inode *inode, int depth,
  80                                  Indirect chain[4], int *err)
  81  {
  82         struct super_block *sb = inode->i_sb;
  83 +       journal_t *journal = EXT4_SB(sb)->s_journal;
  84         Indirect *p = chain;
  85         struct buffer_head *bh;
  86         int ret = -EIO;
  87 @@ -162,7 +163,7 @@ static Indirect *ext4_get_branch(struct inode *inode, int depth,
  88                 }
  89
  90                 if (!bh_uptodate_or_lock(bh)) {
  91 -                       if (bh_submit_read(bh) < 0) {
  92 +                       if (jbd2_bh_submit_read(journal, bh, __func__) < 0) {
  93                                 put_bh(bh);
  94                                 goto failure;
  95                         }
  96 diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
  97 index 831d025e59ad..f0a9f206c18f 100644
  98 --- a/fs/ext4/inode.c
  99 +++ b/fs/ext4/inode.c
 100 @@ -995,13 +995,15 @@ struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
 101                                ext4_lblk_t block, int map_flags)
 102  {
 103         struct buffer_head *bh;
 104 +       journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
 105
 106         bh = ext4_getblk(handle, inode, block, map_flags);
 107         if (IS_ERR(bh))
 108                 return bh;
 109         if (!bh || buffer_uptodate(bh))
 110                 return bh;
 111 -       ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &bh);
 112 +       jbd2_ll_rw_block(journal, REQ_OP_READ, REQ_META | REQ_PRIO, 1, &bh,
 113 +                        __func__);
 114         wait_on_buffer(bh);
 115         if (buffer_uptodate(bh))
 116                 return bh;
 117 @@ -4343,6 +4345,7 @@ static int __ext4_get_inode_loc(struct inode *inode,
 118         struct super_block      *sb = inode->i_sb;
 119         ext4_fsblk_t            block;
 120         int                     inodes_per_block, inode_offset;
 121 +       journal_t               *journal = EXT4_SB(sb)->s_journal;
 122
 123         iloc->bh = NULL;
 124         if (!ext4_valid_inum(sb, inode->i_ino))
 125 @@ -4446,8 +4449,10 @@ static int __ext4_get_inode_loc(struct inode *inode,
 126                         table += num / inodes_per_block;
 127                         if (end > table)
 128                                 end = table;
 129 -                       while (b <= end)
 130 -                               sb_breadahead(sb, b++);
 131 +                       if (journal) {
 132 +                               while (b <= end)
 133 +                                       jbd2_sb_breadahead(journal, sb, b++);
 134 +                       }
 135                 }
 136
 137                 /*
 138 @@ -4458,7 +4463,8 @@ static int __ext4_get_inode_loc(struct inode *inode,
 139                 trace_ext4_load_inode(inode);
 140                 get_bh(bh);
 141                 bh->b_end_io = end_buffer_read_sync;
 142 -               submit_bh(REQ_OP_READ, REQ_META | REQ_PRIO, bh);
 143 +               jbd2_submit_bh(journal, REQ_OP_READ, REQ_META | REQ_PRIO, bh,
 144 +                              __func__);
 145                 wait_on_buffer(bh);
 146                 if (!buffer_uptodate(bh)) {
 147                         EXT4_ERROR_INODE_BLOCK(inode, block,
 148 diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
 149 index 6fc14def0c70..b6c25638f5f4 100644
 150 --- a/fs/ext4/move_extent.c
 151 +++ b/fs/ext4/move_extent.c
 152 @@ -177,6 +177,7 @@ static int
 153  mext_page_mkuptodate(struct page *page, unsigned from, unsigned to)
 154  {
 155         struct inode *inode = page->mapping->host;
 156 +       journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
 157         sector_t block;
 158         struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
 159         unsigned int blocksize, block_start, block_end;
 160 @@ -225,7 +226,7 @@ mext_page_mkuptodate(struct page *page, unsigned from, unsigned to)
 161         for (i = 0; i < nr; i++) {
 162                 bh = arr[i];
 163                 if (!bh_uptodate_or_lock(bh)) {
 164 -                       err = bh_submit_read(bh);
 165 +                       err = jbd2_bh_submit_read(journal, bh, __func__);
 166                         if (err)
 167                                 return err;
 168                 }
 169 diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
 170 index 6ad612c576fc..0812a692db0f 100644
 171 --- a/fs/ext4/namei.c
 172 +++ b/fs/ext4/namei.c
 173 @@ -1361,6 +1361,7 @@ static struct buffer_head * ext4_find_entry (struct inode *dir,
 174         struct buffer_head *bh_use[NAMEI_RA_SIZE];
 175         struct buffer_head *bh, *ret = NULL;
 176         ext4_lblk_t start, block, b;
 177 +       journal_t *journal;
 178         const u8 *name = d_name->name;
 179         int ra_max = 0;         /* Number of bh's in the readahead
 180                                    buffer, bh_use[] */
 181 @@ -1373,6 +1374,7 @@ static struct buffer_head * ext4_find_entry (struct inode *dir,
 182
 183         *res_dir = NULL;
 184         sb = dir->i_sb;
 185 +       journal = EXT4_SB(sb)->s_journal;
 186         namelen = d_name->len;
 187         if (namelen > EXT4_NAME_LEN)
 188                 return NULL;
 189 @@ -1451,9 +1453,9 @@ static struct buffer_head * ext4_find_entry (struct inode *dir,
 190                                 }
 191                                 bh_use[ra_max] = bh;
 192                                 if (bh)
 193 -                                       ll_rw_block(REQ_OP_READ,
 194 -                                                   REQ_META | REQ_PRIO,
 195 -                                                   1, &bh);
 196 +                                       jbd2_ll_rw_block(journal, REQ_OP_READ,
 197 +                                                        REQ_META | REQ_PRIO,
 198 +                                                        1, &bh, __func__);
 199                         }
 200                 }
 201                 if ((bh = bh_use[ra_ptr++]) == NULL)
 202 diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
 203 index c3ed9021b781..8406bca774c8 100644
 204 --- a/fs/ext4/resize.c
 205 +++ b/fs/ext4/resize.c
 206 @@ -1193,10 +1193,12 @@ static int ext4_add_new_descs(handle_t *handle, struct super_block *sb,
 207  static struct buffer_head *ext4_get_bitmap(struct super_block *sb, __u64 block)
 208  {
 209         struct buffer_head *bh = sb_getblk(sb, block);
 210 +       journal_t *journal = EXT4_SB(sb)->s_journal;
 211 +
 212         if (unlikely(!bh))
 213                 return NULL;
 214         if (!bh_uptodate_or_lock(bh)) {
 215 -               if (bh_submit_read(bh) < 0) {
 216 +               if (jbd2_bh_submit_read(journal, bh, __func__) < 0) {
 217                         brelse(bh);
 218                         return NULL;
 219                 }