git.oblomov.eu Git - linux-2.6/blob - fs/ufs/util.c

   1 /*
   2  *  linux/fs/ufs/util.c
   3  *
   4  * Copyright (C) 1998
   5  * Daniel Pirkl <daniel.pirkl@email.cz>
   6  * Charles University, Faculty of Mathematics and Physics
   7  */
   8
   9 #include <linux/string.h>
  10 #include <linux/slab.h>
  11 #include <linux/buffer_head.h>
  12
  13 #include "ufs_fs.h"
  14 #include "ufs.h"
  15 #include "swab.h"
  16 #include "util.h"
  17
  18 struct ufs_buffer_head * _ubh_bread_ (struct ufs_sb_private_info * uspi,
  19         struct super_block *sb, u64 fragment, u64 size)
  20 {
  21         struct ufs_buffer_head * ubh;
  22         unsigned i, j ;
  23         u64  count = 0;
  24         if (size & ~uspi->s_fmask)
  25                 return NULL;
  26         count = size >> uspi->s_fshift;
  27         if (count > UFS_MAXFRAG)
  28                 return NULL;
  29         ubh = (struct ufs_buffer_head *)
  30                 kmalloc (sizeof (struct ufs_buffer_head), GFP_KERNEL);
  31         if (!ubh)
  32                 return NULL;
  33         ubh->fragment = fragment;
  34         ubh->count = count;
  35         for (i = 0; i < count; i++)
  36                 if (!(ubh->bh[i] = sb_bread(sb, fragment + i)))
  37                         goto failed;
  38         for (; i < UFS_MAXFRAG; i++)
  39                 ubh->bh[i] = NULL;
  40         return ubh;
  41 failed:
  42         for (j = 0; j < i; j++)
  43                 brelse (ubh->bh[j]);
  44         kfree(ubh);
  45         return NULL;
  46 }
  47
  48 struct ufs_buffer_head * ubh_bread_uspi (struct ufs_sb_private_info * uspi,
  49         struct super_block *sb, u64 fragment, u64 size)
  50 {
  51         unsigned i, j;
  52         u64 count = 0;
  53         if (size & ~uspi->s_fmask)
  54                 return NULL;
  55         count = size >> uspi->s_fshift;
  56         if (count <= 0 || count > UFS_MAXFRAG)
  57                 return NULL;
  58         USPI_UBH(uspi)->fragment = fragment;
  59         USPI_UBH(uspi)->count = count;
  60         for (i = 0; i < count; i++)
  61                 if (!(USPI_UBH(uspi)->bh[i] = sb_bread(sb, fragment + i)))
  62                         goto failed;
  63         for (; i < UFS_MAXFRAG; i++)
  64                 USPI_UBH(uspi)->bh[i] = NULL;
  65         return USPI_UBH(uspi);
  66 failed:
  67         for (j = 0; j < i; j++)
  68                 brelse (USPI_UBH(uspi)->bh[j]);
  69         return NULL;
  70 }
  71
  72 void ubh_brelse (struct ufs_buffer_head * ubh)
  73 {
  74         unsigned i;
  75         if (!ubh)
  76                 return;
  77         for (i = 0; i < ubh->count; i++)
  78                 brelse (ubh->bh[i]);
  79         kfree (ubh);
  80 }
  81
  82 void ubh_brelse_uspi (struct ufs_sb_private_info * uspi)
  83 {
  84         unsigned i;
  85         if (!USPI_UBH(uspi))
  86                 return;
  87         for ( i = 0; i < USPI_UBH(uspi)->count; i++ ) {
  88                 brelse (USPI_UBH(uspi)->bh[i]);
  89                 USPI_UBH(uspi)->bh[i] = NULL;
  90         }
  91 }
  92
  93 void ubh_mark_buffer_dirty (struct ufs_buffer_head * ubh)
  94 {
  95         unsigned i;
  96         if (!ubh)
  97                 return;
  98         for ( i = 0; i < ubh->count; i++ )
  99                 mark_buffer_dirty (ubh->bh[i]);
 100 }
 101
 102 void ubh_mark_buffer_uptodate (struct ufs_buffer_head * ubh, int flag)
 103 {
 104         unsigned i;
 105         if (!ubh)
 106                 return;
 107         if (flag) {
 108                 for ( i = 0; i < ubh->count; i++ )
 109                         set_buffer_uptodate (ubh->bh[i]);
 110         } else {
 111                 for ( i = 0; i < ubh->count; i++ )
 112                         clear_buffer_uptodate (ubh->bh[i]);
 113         }
 114 }
 115
 116 void ubh_ll_rw_block(int rw, struct ufs_buffer_head *ubh)
 117 {
 118         if (!ubh)
 119                 return;
 120
 121         ll_rw_block(rw, ubh->count, ubh->bh);
 122 }
 123
 124 void ubh_wait_on_buffer (struct ufs_buffer_head * ubh)
 125 {
 126         unsigned i;
 127         if (!ubh)
 128                 return;
 129         for ( i = 0; i < ubh->count; i++ )
 130                 wait_on_buffer (ubh->bh[i]);
 131 }
 132
 133 void ubh_bforget (struct ufs_buffer_head * ubh)
 134 {
 135         unsigned i;
 136         if (!ubh)
 137                 return;
 138         for ( i = 0; i < ubh->count; i++ ) if ( ubh->bh[i] )
 139                 bforget (ubh->bh[i]);
 140 }
 141
 142 int ubh_buffer_dirty (struct ufs_buffer_head * ubh)
 143 {
 144         unsigned i;
 145         unsigned result = 0;
 146         if (!ubh)
 147                 return 0;
 148         for ( i = 0; i < ubh->count; i++ )
 149                 result |= buffer_dirty(ubh->bh[i]);
 150         return result;
 151 }
 152
 153 void _ubh_ubhcpymem_(struct ufs_sb_private_info * uspi,
 154         unsigned char * mem, struct ufs_buffer_head * ubh, unsigned size)
 155 {
 156         unsigned len, bhno;
 157         if (size > (ubh->count << uspi->s_fshift))
 158                 size = ubh->count << uspi->s_fshift;
 159         bhno = 0;
 160         while (size) {
 161                 len = min_t(unsigned int, size, uspi->s_fsize);
 162                 memcpy (mem, ubh->bh[bhno]->b_data, len);
 163                 mem += uspi->s_fsize;
 164                 size -= len;
 165                 bhno++;
 166         }
 167 }
 168
 169 void _ubh_memcpyubh_(struct ufs_sb_private_info * uspi,
 170         struct ufs_buffer_head * ubh, unsigned char * mem, unsigned size)
 171 {
 172         unsigned len, bhno;
 173         if (size > (ubh->count << uspi->s_fshift))
 174                 size = ubh->count << uspi->s_fshift;
 175         bhno = 0;
 176         while (size) {
 177                 len = min_t(unsigned int, size, uspi->s_fsize);
 178                 memcpy (ubh->bh[bhno]->b_data, mem, len);
 179                 mem += uspi->s_fsize;
 180                 size -= len;
 181                 bhno++;
 182         }
 183 }
 184
 185 dev_t
 186 ufs_get_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi)
 187 {
 188         __u32 fs32;
 189         dev_t dev;
 190
 191         if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
 192                 fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[1]);
 193         else
 194                 fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[0]);
 195         switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
 196         case UFS_ST_SUNx86:
 197         case UFS_ST_SUN:
 198                 if ((fs32 & 0xffff0000) == 0 ||
 199                     (fs32 & 0xffff0000) == 0xffff0000)
 200                         dev = old_decode_dev(fs32 & 0x7fff);
 201                 else
 202                         dev = MKDEV(sysv_major(fs32), sysv_minor(fs32));
 203                 break;
 204
 205         default:
 206                 dev = old_decode_dev(fs32);
 207                 break;
 208         }
 209         return dev;
 210 }
 211
 212 void
 213 ufs_set_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi, dev_t dev)
 214 {
 215         __u32 fs32;
 216
 217         switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
 218         case UFS_ST_SUNx86:
 219         case UFS_ST_SUN:
 220                 fs32 = sysv_encode_dev(dev);
 221                 if ((fs32 & 0xffff8000) == 0) {
 222                         fs32 = old_encode_dev(dev);
 223                 }
 224                 break;
 225
 226         default:
 227                 fs32 = old_encode_dev(dev);
 228                 break;
 229         }
 230         if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
 231                 ufsi->i_u1.i_data[1] = cpu_to_fs32(sb, fs32);
 232         else
 233                 ufsi->i_u1.i_data[0] = cpu_to_fs32(sb, fs32);
 234 }
 235
 236 /**
 237  * ufs_get_locked_page() - locate, pin and lock a pagecache page, if not exist
 238  * read it from disk.
 239  * @mapping: the address_space to search
 240  * @index: the page index
 241  *
 242  * Locates the desired pagecache page, if not exist we'll read it,
 243  * locks it, increments its reference
 244  * count and returns its address.
 245  *
 246  */
 247
 248 struct page *ufs_get_locked_page(struct address_space *mapping,
 249                                  pgoff_t index)
 250 {
 251         struct page *page;
 252
 253         page = find_lock_page(mapping, index);
 254         if (!page) {
 255                 page = read_mapping_page(mapping, index, NULL);
 256
 257                 if (IS_ERR(page)) {
 258                         printk(KERN_ERR "ufs_change_blocknr: "
 259                                "read_mapping_page error: ino %lu, index: %lu\n",
 260                                mapping->host->i_ino, index);
 261                         goto out;
 262                 }
 263
 264                 lock_page(page);
 265
 266                 if (unlikely(page->mapping == NULL)) {
 267                         /* Truncate got there first */
 268                         unlock_page(page);
 269                         page_cache_release(page);
 270                         page = NULL;
 271                         goto out;
 272                 }
 273
 274                 if (!PageUptodate(page) || PageError(page)) {
 275                         unlock_page(page);
 276                         page_cache_release(page);
 277
 278                         printk(KERN_ERR "ufs_change_blocknr: "
 279                                "can not read page: ino %lu, index: %lu\n",
 280                                mapping->host->i_ino, index);
 281
 282                         page = ERR_PTR(-EIO);
 283                 }
 284         }
 285 out:
 286         return page;
 287 }