ldiskfs/kernel_patches/patches/ext3-export-64bit-name-hash.patch

   1 Index: linux-2.6.18-194.17.1-ext3/fs/ext3/dir.c
   2 ===================================================================
   3 --- linux-2.6.18-194.17.1-ext3.orig/fs/ext3/dir.c       2010-11-30 22:46:09.000000000 +0300
   4 +++ linux-2.6.18-194.17.1-ext3/fs/ext3/dir.c    2010-12-16 00:10:12.000000000 +0300
   5 @@ -240,19 +240,34 @@ out:
   6  /*
   7   * These functions convert from the major/minor hash to an f_pos
   8   * value.
   9 - *
  10 - * Currently we only use major hash numer.  This is unfortunate, but
  11 - * on 32-bit machines, the same VFS interface is used for lseek and
  12 - * llseek, so if we use the 64 bit offset, then the 32-bit versions of
  13 - * lseek/telldir/seekdir will blow out spectacularly, and from within
  14 - * the ext2 low-level routine, we don't know if we're being called by
  15 - * a 64-bit version of the system call or the 32-bit version of the
  16 - * system call.  Worse yet, NFSv2 only allows for a 32-bit readdir
  17 - * cookie.  Sigh.
  18 + *
  19 + * Whether 64-bit or 32-bit hash value is exported as file pos is
  20 + * controlled by "64bithash" mount option.
  21   */
  22 -#define hash2pos(major, minor) (major >> 1)
  23 -#define pos2maj_hash(pos)      ((pos << 1) & 0xffffffff)
  24 -#define pos2min_hash(pos)      (0)
  25 +
  26 +static inline loff_t hash2pos(struct super_block *sb, __u32 major, __u32 minor)
  27 +{
  28 +       if (test_opt(sb, 64BITHASH))
  29 +               return (((__u64)(major >> 1) << 32) | (__u64)minor);
  30 +       else
  31 +               return (major >> 1);
  32 +}
  33 +
  34 +static inline __u32 pos2maj_hash(struct super_block *sb, loff_t pos)
  35 +{
  36 +       if (test_opt(sb, 64BITHASH))
  37 +               return (((pos >> 32) << 1) & 0xffffffff);
  38 +       else
  39 +               return ((pos << 1) & 0xffffffff);
  40 +}
  41 +
  42 +static inline __u32 pos2min_hash(struct super_block *sb, loff_t pos)
  43 +{
  44 +       if (test_opt(sb, 64BITHASH))
  45 +               return (pos & 0xffffffff);
  46 +       else
  47 +               return (0);
  48 +}
  49
  50  /*
  51   * This structure holds the nodes of the red-black tree used to store
  52 @@ -314,7 +329,7 @@ static void free_rb_tree_fname(struct rb
  53  }
  54
  55
  56 -static struct dir_private_info *create_dir_info(loff_t pos)
  57 +static struct dir_private_info *create_dir_info(struct super_block *sb, loff_t pos)
  58  {
  59         struct dir_private_info *p;
  60
  61 @@ -325,8 +340,8 @@ static struct dir_private_info *create_d
  62         p->curr_node = NULL;
  63         p->extra_fname = NULL;
  64         p->last_pos = 0;
  65 -       p->curr_hash = pos2maj_hash(pos);
  66 -       p->curr_minor_hash = pos2min_hash(pos);
  67 +       p->curr_hash = pos2maj_hash(sb, pos);
  68 +       p->curr_minor_hash = pos2min_hash(sb, pos);
  69         p->next_hash = 0;
  70         return p;
  71  }
  72 @@ -422,7 +437,7 @@ static int call_filldir(struct file * fi
  73                 printk("call_filldir: called with null fname?!?\n");
  74                 return 0;
  75         }
  76 -       curr_pos = hash2pos(fname->hash, fname->minor_hash);
  77 +       curr_pos = hash2pos(sb, fname->hash, fname->minor_hash);
  78         while (fname) {
  79                 error = filldir(dirent, fname->name,
  80                                 fname->name_len, curr_pos,
  81 @@ -447,7 +462,7 @@ static int ext3_dx_readdir(struct file *
  82         int     ret;
  83
  84         if (!info) {
  85 -               info = create_dir_info(filp->f_pos);
  86 +               info = create_dir_info(inode->i_sb, filp->f_pos);
  87                 if (!info)
  88                         return -ENOMEM;
  89                 filp->private_data = info;
  90 @@ -461,8 +476,8 @@ static int ext3_dx_readdir(struct file *
  91                 free_rb_tree_fname(&info->root);
  92                 info->curr_node = NULL;
  93                 info->extra_fname = NULL;
  94 -               info->curr_hash = pos2maj_hash(filp->f_pos);
  95 -               info->curr_minor_hash = pos2min_hash(filp->f_pos);
  96 +               info->curr_hash = pos2maj_hash(inode->i_sb, filp->f_pos);
  97 +               info->curr_minor_hash = pos2min_hash(inode->i_sb, filp->f_pos);
  98         }
  99
 100         /*
 101 Index: linux-2.6.18-194.17.1-ext3/fs/ext3/super.c
 102 ===================================================================
 103 --- linux-2.6.18-194.17.1-ext3.orig/fs/ext3/super.c     2010-11-30 22:48:01.000000000 +0300
 104 +++ linux-2.6.18-194.17.1-ext3/fs/ext3/super.c  2010-12-16 00:11:59.000000000 +0300
 105 @@ -742,6 +742,7 @@ enum {
 106         Opt_grpquota,
 107         Opt_extents, Opt_noextents, Opt_bigendian_extents, Opt_extdebug,
 108         Opt_mballoc, Opt_nomballoc, Opt_stripe, Opt_maxdirsize, Opt_force_over_8tb,
 109 +       Opt_64bithash,
 110  };
 111
 112  static match_table_t tokens = {
 113 @@ -808,6 +809,7 @@ static match_table_t tokens = {
 114         {Opt_force_over_8tb, "force_over_8tb"},
 115         {Opt_resize, "resize"},
 116         {Opt_maxdirsize, "maxdirsize=%u"},
 117 +       {Opt_64bithash, "64bithash"},
 118         {Opt_err, NULL}
 119  };
 120
 121 @@ -1195,6 +1197,9 @@ clear_qf_name:
 122                 case Opt_force_over_8tb:
 123                         force_over_8tb = 1;
 124                         break;
 125 +               case Opt_64bithash:
 126 +                       set_opt(sbi->s_mount_opt, 64BITHASH);
 127 +                       break;
 128                 default:
 129                         printk (KERN_ERR
 130                                 "EXT3-fs: Unrecognized mount option \"%s\" "
 131 Index: linux-2.6.18-194.17.1-ext3/include/linux/ext3_fs.h
 132 ===================================================================
 133 --- linux-2.6.18-194.17.1-ext3.orig/include/linux/ext3_fs.h     2010-11-30 22:52:58.000000000 +0300
 134 +++ linux-2.6.18-194.17.1-ext3/include/linux/ext3_fs.h  2010-12-16 00:12:45.000000000 +0300
 135 @@ -483,6 +483,8 @@ do {                                                                               \
 136  #define EXT3_MOUNT_JOURNAL_ASYNC_COMMIT 0x20000000 /* Journal Async Commit */
 137  #endif
 138
 139 +#define EXT3_MOUNT_64BITHASH            0x40000000 /* export 64-bit name hash */
 140 +
 141  /* Compatibility, for having both ext2_fs.h and ext3_fs.h included at once */
 142  #ifndef clear_opt
 143  #define clear_opt(o, opt)              o &= ~EXT3_MOUNT_##opt