ialloc.c

Version: - FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
    1 /*
    2  *  linux/fs/ufs/ialloc.c
    3  *
    4  * Copyright (c) 1998
    5  * Daniel Pirkl <daniel.pirkl@email.cz>
    6  * Charles University, Faculty of Mathematics and Physics
    7  *
    8  *  from
    9  *
   10  *  linux/fs/ext2/ialloc.c
   11  *
   12  * Copyright (C) 1992, 1993, 1994, 1995
   13  * Remy Card (card@masi.ibp.fr)
   14  * Laboratoire MASI - Institut Blaise Pascal
   15  * Universite Pierre et Marie Curie (Paris VI)
   16  *
   17  *  BSD ufs-inspired inode and directory allocation by 
   18  *  Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
   19  *  Big-endian to little-endian byte-swapping/bitmaps by
   20  *        David S. Miller (davem@caip.rutgers.edu), 1995
   21  */
   22 
   23 #include <linux/fs.h>
   24 #include <linux/ufs_fs.h>
   25 #include <linux/sched.h>
   26 #include <linux/stat.h>
   27 #include <linux/string.h>
   28 #include <linux/locks.h>
   29 #include <linux/quotaops.h>
   30 #include <asm/bitops.h>
   31 #include <asm/byteorder.h>
   32 
   33 #include "swab.h"
   34 #include "util.h"
   35 
   36 #undef UFS_IALLOC_DEBUG
   37 
   38 #ifdef UFS_IALLOC_DEBUG
   39 #define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
   40 #else
   41 #define UFSD(x)
   42 #endif
   43 
   44 /*
   45  * NOTE! When we get the inode, we're the only people
   46  * that have access to it, and as such there are no
   47  * race conditions we have to worry about. The inode
   48  * is not on the hash-lists, and it cannot be reached
   49  * through the filesystem because the directory entry
   50  * has been deleted earlier.
   51  *
   52  * HOWEVER: we must make sure that we get no aliases,
   53  * which means that we have to call "clear_inode()"
   54  * _before_ we mark the inode not in use in the inode
   55  * bitmaps. Otherwise a newly created file might use
   56  * the same inode number (not actually the same pointer
   57  * though), and then we'd have two inodes sharing the
   58  * same inode number and space on the harddisk.
   59  */
   60 void ufs_free_inode (struct inode * inode)
   61 {
   62         struct super_block * sb;
   63         struct ufs_sb_private_info * uspi;
   64         struct ufs_super_block_first * usb1;
   65         struct ufs_cg_private_info * ucpi;
   66         struct ufs_cylinder_group * ucg;
   67         int is_directory;
   68         unsigned ino, cg, bit;
   69         
   70         UFSD(("ENTER, ino %lu\n", inode->i_ino))
   71 
   72         sb = inode->i_sb;
   73         uspi = sb->u.ufs_sb.s_uspi;
   74         usb1 = ubh_get_usb_first(USPI_UBH);
   75         
   76         ino = inode->i_ino;
   77 
   78         lock_super (sb);
   79 
   80         if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) {
   81                 ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino);
   82                 unlock_super (sb);
   83                 return;
   84         }
   85         
   86         cg = ufs_inotocg (ino);
   87         bit = ufs_inotocgoff (ino);
   88         ucpi = ufs_load_cylinder (sb, cg);
   89         if (!ucpi) {
   90                 unlock_super (sb);
   91                 return;
   92         }
   93         ucg = ubh_get_ucg(UCPI_UBH);
   94         if (!ufs_cg_chkmagic(sb, ucg))
   95                 ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number");
   96 
   97         ucg->cg_time = cpu_to_fs32(sb, CURRENT_TIME);
   98 
   99         is_directory = S_ISDIR(inode->i_mode);
  100 
  101         DQUOT_FREE_INODE(inode);
  102         DQUOT_DROP(inode);
  103 
  104         clear_inode (inode);
  105 
  106         if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit))
  107                 ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino);
  108         else {
  109                 ubh_clrbit (UCPI_UBH, ucpi->c_iusedoff, bit);
  110                 if (ino < ucpi->c_irotor)
  111                         ucpi->c_irotor = ino;
  112                 fs32_add(sb, &ucg->cg_cs.cs_nifree, 1);
  113                 fs32_add(sb, &usb1->fs_cstotal.cs_nifree, 1);
  114                 fs32_add(sb, &sb->fs_cs(cg).cs_nifree, 1);
  115 
  116                 if (is_directory) {
  117                         fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1);
  118                         fs32_sub(sb, &usb1->fs_cstotal.cs_ndir, 1);
  119                         fs32_sub(sb, &sb->fs_cs(cg).cs_ndir, 1);
  120                 }
  121         }
  122 
  123         ubh_mark_buffer_dirty (USPI_UBH);
  124         ubh_mark_buffer_dirty (UCPI_UBH);
  125         if (sb->s_flags & MS_SYNCHRONOUS) {
  126                 ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi);
  127                 ubh_wait_on_buffer (UCPI_UBH);
  128         }
  129         
  130         sb->s_dirt = 1;
  131         unlock_super (sb);
  132         UFSD(("EXIT\n"))
  133 }
  134 
  135 /*
  136  * There are two policies for allocating an inode.  If the new inode is
  137  * a directory, then a forward search is made for a block group with both
  138  * free space and a low directory-to-inode ratio; if that fails, then of
  139  * the groups with above-average free space, that group with the fewest
  140  * directories already is chosen.
  141  *
  142  * For other inodes, search forward from the parent directory's block
  143  * group to find a free inode.
  144  */
  145 struct inode * ufs_new_inode (const struct inode * dir, int mode)
  146 {
  147         struct super_block * sb;
  148         struct ufs_sb_private_info * uspi;
  149         struct ufs_super_block_first * usb1;
  150         struct ufs_cg_private_info * ucpi;
  151         struct ufs_cylinder_group * ucg;
  152         struct inode * inode;
  153         unsigned cg, bit, i, j, start;
  154 
  155         UFSD(("ENTER\n"))
  156         
  157         /* Cannot create files in a deleted directory */
  158         if (!dir || !dir->i_nlink)
  159                 return ERR_PTR(-EPERM);
  160         sb = dir->i_sb;
  161         inode = new_inode(sb);
  162         if (!inode)
  163                 return ERR_PTR(-ENOMEM);
  164         uspi = sb->u.ufs_sb.s_uspi;
  165         usb1 = ubh_get_usb_first(USPI_UBH);
  166 
  167         lock_super (sb);
  168 
  169         /*
  170          * Try to place the inode in its parent directory
  171          */
  172         i = ufs_inotocg(dir->i_ino);
  173         if (sb->fs_cs(i).cs_nifree) {
  174                 cg = i;
  175                 goto cg_found;
  176         }
  177 
  178         /*
  179          * Use a quadratic hash to find a group with a free inode
  180          */
  181         for ( j = 1; j < uspi->s_ncg; j <<= 1 ) {
  182                 i += j;
  183                 if (i >= uspi->s_ncg)
  184                         i -= uspi->s_ncg;
  185                 if (sb->fs_cs(i).cs_nifree) {
  186                         cg = i;
  187                         goto cg_found;
  188                 }
  189         }
  190 
  191         /*
  192          * That failed: try linear search for a free inode
  193          */
  194         i = ufs_inotocg(dir->i_ino) + 1;
  195         for (j = 2; j < uspi->s_ncg; j++) {
  196                 i++;
  197                 if (i >= uspi->s_ncg)
  198                         i = 0;
  199                 if (sb->fs_cs(i).cs_nifree) {
  200                         cg = i;
  201                         goto cg_found;
  202                 }
  203         }
  204         
  205         goto failed;
  206 
  207 cg_found:
  208         ucpi = ufs_load_cylinder (sb, cg);
  209         if (!ucpi)
  210                 goto failed;
  211         ucg = ubh_get_ucg(UCPI_UBH);
  212         if (!ufs_cg_chkmagic(sb, ucg)) 
  213                 ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number");
  214 
  215         start = ucpi->c_irotor;
  216         bit = ubh_find_next_zero_bit (UCPI_UBH, ucpi->c_iusedoff, uspi->s_ipg, start);
  217         if (!(bit < uspi->s_ipg)) {
  218                 bit = ubh_find_first_zero_bit (UCPI_UBH, ucpi->c_iusedoff, start);
  219                 if (!(bit < start)) {
  220                         ufs_error (sb, "ufs_new_inode",
  221                             "cylinder group %u corrupted - error in inode bitmap\n", cg);
  222                         goto failed;
  223                 }
  224         }
  225         UFSD(("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg))
  226         if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit))
  227                 ubh_setbit (UCPI_UBH, ucpi->c_iusedoff, bit);
  228         else {
  229                 ufs_panic (sb, "ufs_new_inode", "internal error");
  230                 goto failed;
  231         }
  232         
  233         fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1);
  234         fs32_sub(sb, &usb1->fs_cstotal.cs_nifree, 1);
  235         fs32_sub(sb, &sb->fs_cs(cg).cs_nifree, 1);
  236         
  237         if (S_ISDIR(mode)) {
  238                 fs32_add(sb, &ucg->cg_cs.cs_ndir, 1);
  239                 fs32_add(sb, &usb1->fs_cstotal.cs_ndir, 1);
  240                 fs32_add(sb, &sb->fs_cs(cg).cs_ndir, 1);
  241         }
  242 
  243         ubh_mark_buffer_dirty (USPI_UBH);
  244         ubh_mark_buffer_dirty (UCPI_UBH);
  245         if (sb->s_flags & MS_SYNCHRONOUS) {
  246                 ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi);
  247                 ubh_wait_on_buffer (UCPI_UBH);
  248         }
  249         sb->s_dirt = 1;
  250 
  251         inode->i_mode = mode;
  252         inode->i_uid = current->fsuid;
  253         if (dir->i_mode & S_ISGID) {
  254                 inode->i_gid = dir->i_gid;
  255                 if (S_ISDIR(mode))
  256                         inode->i_mode |= S_ISGID;
  257         } else
  258                 inode->i_gid = current->fsgid;
  259 
  260         inode->i_ino = cg * uspi->s_ipg + bit;
  261         inode->i_blksize = PAGE_SIZE;   /* This is the optimal IO size (for stat), not the fs block size */
  262         inode->i_blocks = 0;
  263         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
  264         inode->u.ufs_i.i_flags = dir->u.ufs_i.i_flags;
  265         inode->u.ufs_i.i_lastfrag = 0;
  266 
  267         insert_inode_hash(inode);
  268         mark_inode_dirty(inode);
  269 
  270         unlock_super (sb);
  271 
  272         if (DQUOT_ALLOC_INODE(inode)) {
  273                 DQUOT_DROP(inode);
  274                 inode->i_flags |= S_NOQUOTA;
  275                 inode->i_nlink = 0;
  276                 iput(inode);
  277                 return ERR_PTR(-EDQUOT);
  278         }
  279 
  280         UFSD(("allocating inode %lu\n", inode->i_ino))
  281         UFSD(("EXIT\n"))
  282         return inode;
  283 
  284 failed:
  285         unlock_super (sb);
  286         make_bad_inode(inode);
  287         iput (inode);
  288         UFSD(("EXIT (FAILED)\n"))
  289         return ERR_PTR(-ENOSPC);
  290 }
Cache object: 6d6be52c67d9ab63c320d32368100a34
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.
FreeBSD/Linux Kernel Cross Reference sys/fs/ufs/ialloc.c

FreeBSD/Linux Kernel Cross Reference
sys/fs/ufs/ialloc.c
