fs/ufs/util.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ufs/util.c
   4  *
   5  * Copyright (C) 1998
   6  * Daniel Pirkl <daniel.pirkl@email.cz>
   7  * Charles University, Faculty of Mathematics and Physics
   8  */
   9
  10 #include <linux/string.h>
  11 #include <linux/slab.h>
  12 #include <linux/buffer_head.h>
  13
  14 #include "ufs_fs.h"
  15 #include "ufs.h"
  16 #include "swab.h"
  17 #include "util.h"
  18
  19 struct ufs_buffer_head * _ubh_bread_ (struct ufs_sb_private_info * uspi,
  20         struct super_block *sb, u64 fragment, u64 size)
  21 {
  22         struct ufs_buffer_head * ubh;
  23         unsigned i, j ;
  24         u64  count = 0;
  25         if (size & ~uspi->s_fmask)
  26                 return NULL;
  27         count = size >> uspi->s_fshift;
  28         if (count > UFS_MAXFRAG)
  29                 return NULL;
  30         ubh = kmalloc (sizeof (struct ufs_buffer_head), GFP_NOFS);
  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_sync_block(struct ufs_buffer_head *ubh)
 103 {
 104         if (ubh) {
 105                 unsigned i;
 106
 107                 for (i = 0; i < ubh->count; i++)
 108                         write_dirty_buffer(ubh->bh[i], 0);
 109
 110                 for (i = 0; i < ubh->count; i++)
 111                         wait_on_buffer(ubh->bh[i]);
 112         }
 113 }
 114
 115 void ubh_bforget (struct ufs_buffer_head * ubh)
 116 {
 117         unsigned i;
 118         if (!ubh)
 119                 return;
 120         for ( i = 0; i < ubh->count; i++ ) if ( ubh->bh[i] )
 121                 bforget (ubh->bh[i]);
 122 }
 123
 124 int ubh_buffer_dirty (struct ufs_buffer_head * ubh)
 125 {
 126         unsigned i;
 127         unsigned result = 0;
 128         if (!ubh)
 129                 return 0;
 130         for ( i = 0; i < ubh->count; i++ )
 131                 result |= buffer_dirty(ubh->bh[i]);
 132         return result;
 133 }
 134
 135 dev_t
 136 ufs_get_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi)
 137 {
 138         __u32 fs32;
 139         dev_t dev;
 140
 141         if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
 142                 fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[1]);
 143         else
 144                 fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[0]);
 145         switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
 146         case UFS_ST_SUNx86:
 147         case UFS_ST_SUN:
 148                 if ((fs32 & 0xffff0000) == 0 ||
 149                     (fs32 & 0xffff0000) == 0xffff0000)
 150                         dev = old_decode_dev(fs32 & 0x7fff);
 151                 else
 152                         dev = MKDEV(sysv_major(fs32), sysv_minor(fs32));
 153                 break;
 154
 155         default:
 156                 dev = old_decode_dev(fs32);
 157                 break;
 158         }
 159         return dev;
 160 }
 161
 162 void
 163 ufs_set_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi, dev_t dev)
 164 {
 165         __u32 fs32;
 166
 167         switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
 168         case UFS_ST_SUNx86:
 169         case UFS_ST_SUN:
 170                 fs32 = sysv_encode_dev(dev);
 171                 if ((fs32 & 0xffff8000) == 0) {
 172                         fs32 = old_encode_dev(dev);
 173                 }
 174                 break;
 175
 176         default:
 177                 fs32 = old_encode_dev(dev);
 178                 break;
 179         }
 180         if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
 181                 ufsi->i_u1.i_data[1] = cpu_to_fs32(sb, fs32);
 182         else
 183                 ufsi->i_u1.i_data[0] = cpu_to_fs32(sb, fs32);
 184 }
 185
 186 /**
 187  * ufs_get_locked_folio() - locate, pin and lock a pagecache folio, if not exist
 188  * read it from disk.
 189  * @mapping: the address_space to search
 190  * @index: the page index
 191  *
 192  * Locates the desired pagecache folio, if not exist we'll read it,
 193  * locks it, increments its reference
 194  * count and returns its address.
 195  *
 196  */
 197 struct folio *ufs_get_locked_folio(struct address_space *mapping,
 198                                  pgoff_t index)
 199 {
 200         struct inode *inode = mapping->host;
 201         struct folio *folio = filemap_lock_folio(mapping, index);
 202         if (IS_ERR(folio)) {
 203                 folio = read_mapping_folio(mapping, index, NULL);
 204
 205                 if (IS_ERR(folio)) {
 206                         printk(KERN_ERR "ufs_change_blocknr: read_mapping_folio error: ino %lu, index: %lu\n",
 207                                mapping->host->i_ino, index);
 208                         return folio;
 209                 }
 210
 211                 folio_lock(folio);
 212
 213                 if (unlikely(folio->mapping == NULL)) {
 214                         /* Truncate got there first */
 215                         folio_unlock(folio);
 216                         folio_put(folio);
 217                         return NULL;
 218                 }
 219         }
 220         if (!folio_buffers(folio))
 221                 create_empty_buffers(folio, 1 << inode->i_blkbits, 0);
 222         return folio;
 223 }