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/*
* linux/fs/ufs/ialloc.c
*
* Copyright (c) 1998
* Daniel Pirkl <daniel.pirkl@email.cz>
* Charles University, Faculty of Mathematics and Physics
*
* from
*
* linux/fs/ext2/ialloc.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* BSD ufs-inspired inode and directory allocation by
* Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
* Big-endian to little-endian byte-swapping/bitmaps by
* David S. Miller (davem@caip.rutgers.edu), 1995
*/
#include <linux/fs.h>
#include <linux/ufs_fs.h>
#include <linux/sched.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/locks.h>
#include <linux/quotaops.h>
#include <asm/bitops.h>
#include <asm/byteorder.h>
#include "swab.h"
#include "util.h"
#undef UFS_IALLOC_DEBUG
#ifdef UFS_IALLOC_DEBUG
#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
#else
#define UFSD(x)
#endif
/*
* NOTE! When we get the inode, we're the only people
* that have access to it, and as such there are no
* race conditions we have to worry about. The inode
* is not on the hash-lists, and it cannot be reached
* through the filesystem because the directory entry
* has been deleted earlier.
*
* HOWEVER: we must make sure that we get no aliases,
* which means that we have to call "clear_inode()"
* _before_ we mark the inode not in use in the inode
* bitmaps. Otherwise a newly created file might use
* the same inode number (not actually the same pointer
* though), and then we'd have two inodes sharing the
* same inode number and space on the harddisk.
*/
void ufs_free_inode (struct inode * inode)
{
struct super_block * sb;
struct ufs_sb_private_info * uspi;
struct ufs_super_block_first * usb1;
struct ufs_cg_private_info * ucpi;
struct ufs_cylinder_group * ucg;
int is_directory;
unsigned ino, cg, bit;
UFSD(("ENTER, ino %lu\n", inode->i_ino))
sb = inode->i_sb;
uspi = sb->u.ufs_sb.s_uspi;
usb1 = ubh_get_usb_first(USPI_UBH);
ino = inode->i_ino;
lock_super (sb);
if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) {
ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino);
unlock_super (sb);
return;
}
cg = ufs_inotocg (ino);
bit = ufs_inotocgoff (ino);
ucpi = ufs_load_cylinder (sb, cg);
if (!ucpi) {
unlock_super (sb);
return;
}
ucg = ubh_get_ucg(UCPI_UBH);
if (!ufs_cg_chkmagic(sb, ucg))
ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number");
ucg->cg_time = cpu_to_fs32(sb, CURRENT_TIME);
is_directory = S_ISDIR(inode->i_mode);
DQUOT_FREE_INODE(inode);
DQUOT_DROP(inode);
clear_inode (inode);
if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit))
ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino);
else {
ubh_clrbit (UCPI_UBH, ucpi->c_iusedoff, bit);
if (ino < ucpi->c_irotor)
ucpi->c_irotor = ino;
fs32_add(sb, &ucg->cg_cs.cs_nifree, 1);
fs32_add(sb, &usb1->fs_cstotal.cs_nifree, 1);
fs32_add(sb, &sb->fs_cs(cg).cs_nifree, 1);
if (is_directory) {
fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1);
fs32_sub(sb, &usb1->fs_cstotal.cs_ndir, 1);
fs32_sub(sb, &sb->fs_cs(cg).cs_ndir, 1);
}
}
ubh_mark_buffer_dirty (USPI_UBH);
ubh_mark_buffer_dirty (UCPI_UBH);
if (sb->s_flags & MS_SYNCHRONOUS) {
ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi);
ubh_wait_on_buffer (UCPI_UBH);
}
sb->s_dirt = 1;
unlock_super (sb);
UFSD(("EXIT\n"))
}
/*
* There are two policies for allocating an inode. If the new inode is
* a directory, then a forward search is made for a block group with both
* free space and a low directory-to-inode ratio; if that fails, then of
* the groups with above-average free space, that group with the fewest
* directories already is chosen.
*
* For other inodes, search forward from the parent directory's block
* group to find a free inode.
*/
struct inode * ufs_new_inode (const struct inode * dir, int mode)
{
struct super_block * sb;
struct ufs_sb_private_info * uspi;
struct ufs_super_block_first * usb1;
struct ufs_cg_private_info * ucpi;
struct ufs_cylinder_group * ucg;
struct inode * inode;
unsigned cg, bit, i, j, start;
UFSD(("ENTER\n"))
/* Cannot create files in a deleted directory */
if (!dir || !dir->i_nlink)
return ERR_PTR(-EPERM);
sb = dir->i_sb;
inode = new_inode(sb);
if (!inode)
return ERR_PTR(-ENOMEM);
uspi = sb->u.ufs_sb.s_uspi;
usb1 = ubh_get_usb_first(USPI_UBH);
lock_super (sb);
/*
* Try to place the inode in its parent directory
*/
i = ufs_inotocg(dir->i_ino);
if (sb->fs_cs(i).cs_nifree) {
cg = i;
goto cg_found;
}
/*
* Use a quadratic hash to find a group with a free inode
*/
for ( j = 1; j < uspi->s_ncg; j <<= 1 ) {
i += j;
if (i >= uspi->s_ncg)
i -= uspi->s_ncg;
if (sb->fs_cs(i).cs_nifree) {
cg = i;
goto cg_found;
}
}
/*
* That failed: try linear search for a free inode
*/
i = ufs_inotocg(dir->i_ino) + 1;
for (j = 2; j < uspi->s_ncg; j++) {
i++;
if (i >= uspi->s_ncg)
i = 0;
if (sb->fs_cs(i).cs_nifree) {
cg = i;
goto cg_found;
}
}
goto failed;
cg_found:
ucpi = ufs_load_cylinder (sb, cg);
if (!ucpi)
goto failed;
ucg = ubh_get_ucg(UCPI_UBH);
if (!ufs_cg_chkmagic(sb, ucg))
ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number");
start = ucpi->c_irotor;
bit = ubh_find_next_zero_bit (UCPI_UBH, ucpi->c_iusedoff, uspi->s_ipg, start);
if (!(bit < uspi->s_ipg)) {
bit = ubh_find_first_zero_bit (UCPI_UBH, ucpi->c_iusedoff, start);
if (!(bit < start)) {
ufs_error (sb, "ufs_new_inode",
"cylinder group %u corrupted - error in inode bitmap\n", cg);
goto failed;
}
}
UFSD(("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg))
if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit))
ubh_setbit (UCPI_UBH, ucpi->c_iusedoff, bit);
else {
ufs_panic (sb, "ufs_new_inode", "internal error");
goto failed;
}
fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1);
fs32_sub(sb, &usb1->fs_cstotal.cs_nifree, 1);
fs32_sub(sb, &sb->fs_cs(cg).cs_nifree, 1);
if (S_ISDIR(mode)) {
fs32_add(sb, &ucg->cg_cs.cs_ndir, 1);
fs32_add(sb, &usb1->fs_cstotal.cs_ndir, 1);
fs32_add(sb, &sb->fs_cs(cg).cs_ndir, 1);
}
ubh_mark_buffer_dirty (USPI_UBH);
ubh_mark_buffer_dirty (UCPI_UBH);
if (sb->s_flags & MS_SYNCHRONOUS) {
ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi);
ubh_wait_on_buffer (UCPI_UBH);
}
sb->s_dirt = 1;
inode->i_mode = mode;
inode->i_uid = current->fsuid;
if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
inode->i_mode |= S_ISGID;
} else
inode->i_gid = current->fsgid;
inode->i_ino = cg * uspi->s_ipg + bit;
inode->i_blksize = PAGE_SIZE; /* This is the optimal IO size (for stat), not the fs block size */
inode->i_blocks = 0;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->u.ufs_i.i_flags = dir->u.ufs_i.i_flags;
inode->u.ufs_i.i_lastfrag = 0;
insert_inode_hash(inode);
mark_inode_dirty(inode);
unlock_super (sb);
if (DQUOT_ALLOC_INODE(inode)) {
DQUOT_DROP(inode);
inode->i_flags |= S_NOQUOTA;
inode->i_nlink = 0;
iput(inode);
return ERR_PTR(-EDQUOT);
}
UFSD(("allocating inode %lu\n", inode->i_ino))
UFSD(("EXIT\n"))
return inode;
failed:
unlock_super (sb);
make_bad_inode(inode);
iput (inode);
UFSD(("EXIT (FAILED)\n"))
return ERR_PTR(-ENOSPC);
}
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