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