Viewing file:  super.c (13.58 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
* linux/fs/affs/inode.c
*
* (c) 1996 Hans-Joachim Widmaier - Rewritten
*
* (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
*
* (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
*
* (C) 1991 Linus Torvalds - minix filesystem
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/stat.h>
#include <linux/sched.h>
#include <linux/affs_fs.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/locks.h>
#include <linux/genhd.h>
#include <linux/amigaffs.h>
#include <linux/major.h>
#include <linux/blkdev.h>
#include <linux/init.h>
#include <asm/system.h>
#include <asm/uaccess.h>
extern int *blk_size[];
extern struct timezone sys_tz;
static int affs_statfs(struct super_block *sb, struct statfs *buf);
static int affs_remount (struct super_block *sb, int *flags, char *data);
static void
affs_put_super(struct super_block *sb)
{
pr_debug("AFFS: put_super()\n");
if (!(sb->s_flags & MS_RDONLY)) {
AFFS_ROOT_TAIL(sb, AFFS_SB->s_root_bh)->bm_flag = be32_to_cpu(1);
secs_to_datestamp(CURRENT_TIME,
&AFFS_ROOT_TAIL(sb, AFFS_SB->s_root_bh)->disk_change);
affs_fix_checksum(sb, AFFS_SB->s_root_bh);
mark_buffer_dirty(AFFS_SB->s_root_bh);
}
affs_brelse(AFFS_SB->s_bmap_bh);
if (AFFS_SB->s_prefix)
kfree(AFFS_SB->s_prefix);
kfree(AFFS_SB->s_bitmap);
affs_brelse(AFFS_SB->s_root_bh);
return;
}
static void
affs_write_super(struct super_block *sb)
{
int clean = 2;
if (!(sb->s_flags & MS_RDONLY)) {
// if (AFFS_SB->s_bitmap[i].bm_bh) {
// if (buffer_dirty(AFFS_SB->s_bitmap[i].bm_bh)) {
// clean = 0;
AFFS_ROOT_TAIL(sb, AFFS_SB->s_root_bh)->bm_flag = be32_to_cpu(clean);
secs_to_datestamp(CURRENT_TIME,
&AFFS_ROOT_TAIL(sb, AFFS_SB->s_root_bh)->disk_change);
affs_fix_checksum(sb, AFFS_SB->s_root_bh);
mark_buffer_dirty(AFFS_SB->s_root_bh);
sb->s_dirt = !clean; /* redo until bitmap synced */
} else
sb->s_dirt = 0;
pr_debug("AFFS: write_super() at %lu, clean=%d\n", CURRENT_TIME, clean);
}
static struct super_operations affs_sops = {
read_inode: affs_read_inode,
write_inode: affs_write_inode,
put_inode: affs_put_inode,
delete_inode: affs_delete_inode,
clear_inode: affs_clear_inode,
put_super: affs_put_super,
write_super: affs_write_super,
statfs: affs_statfs,
remount_fs: affs_remount,
};
static int
parse_options(char *options, uid_t *uid, gid_t *gid, int *mode, int *reserved, s32 *root,
int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)
{
char *this_char, *value, *optn;
int f;
/* Fill in defaults */
*uid = current->uid;
*gid = current->gid;
*reserved = 2;
*root = -1;
*blocksize = -1;
volume[0] = ':';
volume[1] = 0;
*mount_opts = 0;
if (!options)
return 1;
for (this_char = strtok(options,","); this_char; this_char = strtok(NULL,",")) {
f = 0;
if ((value = strchr(this_char,'=')) != NULL)
*value++ = 0;
if ((optn = "protect") && !strcmp(this_char, optn)) {
if (value)
goto out_inv_arg;
*mount_opts |= SF_IMMUTABLE;
} else if ((optn = "verbose") && !strcmp(this_char, optn)) {
if (value)
goto out_inv_arg;
*mount_opts |= SF_VERBOSE;
} else if ((optn = "mufs") && !strcmp(this_char, optn)) {
if (value)
goto out_inv_arg;
*mount_opts |= SF_MUFS;
} else if ((f = !strcmp(this_char,"setuid")) || !strcmp(this_char,"setgid")) {
if (value) {
if (!*value) {
printk("AFFS: Argument for set[ug]id option missing\n");
return 0;
} else {
(f ? *uid : *gid) = simple_strtoul(value,&value,0);
if (*value) {
printk("AFFS: Bad set[ug]id argument\n");
return 0;
}
*mount_opts |= f ? SF_SETUID : SF_SETGID;
}
}
} else if (!strcmp(this_char,"prefix")) {
optn = "prefix";
if (!value || !*value)
goto out_no_arg;
if (*prefix) { /* Free any previous prefix */
kfree(*prefix);
*prefix = NULL;
}
*prefix = kmalloc(strlen(value) + 1,GFP_KERNEL);
if (!*prefix)
return 0;
strcpy(*prefix,value);
*mount_opts |= SF_PREFIX;
} else if (!strcmp(this_char,"volume")) {
optn = "volume";
if (!value || !*value)
goto out_no_arg;
if (strlen(value) > 30)
value[30] = 0;
strncpy(volume,value,30);
} else if (!strcmp(this_char,"mode")) {
optn = "mode";
if (!value || !*value)
goto out_no_arg;
*mode = simple_strtoul(value,&value,8) & 0777;
if (*value)
return 0;
*mount_opts |= SF_SETMODE;
} else if (!strcmp(this_char,"reserved")) {
optn = "reserved";
if (!value || !*value)
goto out_no_arg;
*reserved = simple_strtoul(value,&value,0);
if (*value)
return 0;
} else if (!strcmp(this_char,"root")) {
optn = "root";
if (!value || !*value)
goto out_no_arg;
*root = simple_strtoul(value,&value,0);
if (*value)
return 0;
} else if (!strcmp(this_char,"bs")) {
optn = "bs";
if (!value || !*value)
goto out_no_arg;
*blocksize = simple_strtoul(value,&value,0);
if (*value)
return 0;
if (*blocksize != 512 && *blocksize != 1024 && *blocksize != 2048
&& *blocksize != 4096) {
printk ("AFFS: Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
return 0;
}
} else if (!strcmp (this_char, "grpquota")
|| !strcmp (this_char, "noquota")
|| !strcmp (this_char, "quota")
|| !strcmp (this_char, "usrquota"))
/* Silently ignore the quota options */
;
else {
printk("AFFS: Unrecognized mount option %s\n", this_char);
return 0;
}
}
return 1;
out_no_arg:
printk("AFFS: The %s option requires an argument\n", optn);
return 0;
out_inv_arg:
printk("AFFS: Option %s does not take an argument\n", optn);
return 0;
}
/* This function definitely needs to be split up. Some fine day I'll
* hopefully have the guts to do so. Until then: sorry for the mess.
*/
static struct super_block *
affs_read_super(struct super_block *sb, void *data, int silent)
{
struct buffer_head *root_bh = NULL;
struct buffer_head *boot_bh;
struct inode *root_inode = NULL;
kdev_t dev = sb->s_dev;
s32 root_block;
int blocks, size, blocksize;
u32 chksum;
int num_bm;
int i, j;
s32 key;
uid_t uid;
gid_t gid;
int reserved;
unsigned long mount_flags;
pr_debug("AFFS: read_super(%s)\n",data ? (const char *)data : "no options");
sb->s_magic = AFFS_SUPER_MAGIC;
sb->s_op = &affs_sops;
memset(AFFS_SB, 0, sizeof(*AFFS_SB));
init_MUTEX(&AFFS_SB->s_bmlock);
if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block,
&blocksize,&AFFS_SB->s_prefix,
AFFS_SB->s_volume, &mount_flags)) {
printk(KERN_ERR "AFFS: Error parsing options\n");
return NULL;
}
/* N.B. after this point s_prefix must be released */
AFFS_SB->s_flags = mount_flags;
AFFS_SB->s_mode = i;
AFFS_SB->s_uid = uid;
AFFS_SB->s_gid = gid;
AFFS_SB->s_reserved= reserved;
/* Get the size of the device in 512-byte blocks.
* If we later see that the partition uses bigger
* blocks, we will have to change it.
*/
blocks = blk_size[MAJOR(dev)] ? blk_size[MAJOR(dev)][MINOR(dev)] : 0;
if (!blocks) {
printk(KERN_ERR "AFFS: Could not determine device size\n");
goto out_error;
}
size = (BLOCK_SIZE / 512) * blocks;
pr_debug("AFFS: initial blksize=%d, blocks=%d\n", 512, blocks);
affs_set_blocksize(sb, PAGE_SIZE);
/* Try to find root block. Its location depends on the block size. */
i = 512;
j = 4096;
if (blocksize > 0) {
i = j = blocksize;
size = size / (blocksize / 512);
}
for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) {
AFFS_SB->s_root_block = root_block;
if (root_block < 0)
AFFS_SB->s_root_block = (reserved + size - 1) / 2;
pr_debug("AFFS: setting blocksize to %d\n", blocksize);
affs_set_blocksize(sb, blocksize);
AFFS_SB->s_partition_size = size;
/* The root block location that was calculated above is not
* correct if the partition size is an odd number of 512-
* byte blocks, which will be rounded down to a number of
* 1024-byte blocks, and if there were an even number of
* reserved blocks. Ideally, all partition checkers should
* report the real number of blocks of the real blocksize,
* but since this just cannot be done, we have to try to
* find the root block anyways. In the above case, it is one
* block behind the calculated one. So we check this one, too.
*/
for (num_bm = 0; num_bm < 2; num_bm++) {
pr_debug("AFFS: Dev %s, trying root=%u, bs=%d, "
"size=%d, reserved=%d\n",
kdevname(dev),
AFFS_SB->s_root_block + num_bm,
blocksize, size, reserved);
root_bh = affs_bread(sb, AFFS_SB->s_root_block + num_bm);
if (!root_bh)
continue;
if (!affs_checksum_block(sb, root_bh) &&
be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT &&
be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) {
AFFS_SB->s_hashsize = blocksize / 4 - 56;
AFFS_SB->s_root_block += num_bm;
key = 1;
goto got_root;
}
affs_brelse(root_bh);
root_bh = NULL;
}
}
if (!silent)
printk(KERN_ERR "AFFS: No valid root block on device %s\n",
kdevname(dev));
goto out_error;
/* N.B. after this point bh must be released */
got_root:
root_block = AFFS_SB->s_root_block;
sb->s_blocksize_bits = blocksize == 512 ? 9 :
blocksize == 1024 ? 10 :
blocksize == 2048 ? 11 : 12;
/* Find out which kind of FS we have */
boot_bh = sb_bread(sb, 0);
if (!boot_bh) {
printk(KERN_ERR "AFFS: Cannot read boot block\n");
goto out_error;
}
chksum = be32_to_cpu(*(u32 *)boot_bh->b_data);
brelse(boot_bh);
/* Dircache filesystems are compatible with non-dircache ones
* when reading. As long as they aren't supported, writing is
* not recommended.
*/
if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS
|| chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) {
printk(KERN_NOTICE "AFFS: Dircache FS - mounting %s read only\n",
kdevname(dev));
sb->s_flags |= MS_RDONLY;
AFFS_SB->s_flags |= SF_READONLY;
}
switch (chksum) {
case MUFS_FS:
case MUFS_INTLFFS:
case MUFS_DCFFS:
AFFS_SB->s_flags |= SF_MUFS;
/* fall thru */
case FS_INTLFFS:
case FS_DCFFS:
AFFS_SB->s_flags |= SF_INTL;
break;
case MUFS_FFS:
AFFS_SB->s_flags |= SF_MUFS;
break;
case FS_FFS:
break;
case MUFS_OFS:
AFFS_SB->s_flags |= SF_MUFS;
/* fall thru */
case FS_OFS:
AFFS_SB->s_flags |= SF_OFS;
sb->s_flags |= MS_NOEXEC;
break;
case MUFS_DCOFS:
case MUFS_INTLOFS:
AFFS_SB->s_flags |= SF_MUFS;
case FS_DCOFS:
case FS_INTLOFS:
AFFS_SB->s_flags |= SF_INTL | SF_OFS;
sb->s_flags |= MS_NOEXEC;
break;
default:
printk(KERN_ERR "AFFS: Unknown filesystem on device %s: %08X\n",
kdevname(dev), chksum);
goto out_error;
}
if (mount_flags & SF_VERBOSE) {
chksum = cpu_to_be32(chksum);
printk(KERN_NOTICE "AFFS: Mounting volume \"%*s\": Type=%.3s\\%c, Blocksize=%d\n",
AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0],
AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,
(char *)&chksum,((char *)&chksum)[3] + '0',blocksize);
}
sb->s_flags |= MS_NODEV | MS_NOSUID;
AFFS_SB->s_data_blksize = sb->s_blocksize;
if (AFFS_SB->s_flags & SF_OFS)
AFFS_SB->s_data_blksize -= 24;
/* Keep super block in cache */
AFFS_SB->s_root_bh = root_bh;
/* N.B. after this point s_root_bh must be released */
if (affs_init_bitmap(sb))
goto out_error;
/* set up enough so that it can read an inode */
root_inode = iget(sb, root_block);
sb->s_root = d_alloc_root(root_inode);
if (!sb->s_root) {
printk(KERN_ERR "AFFS: Get root inode failed\n");
goto out_error;
}
sb->s_root->d_op = &affs_dentry_operations;
pr_debug("AFFS: s_flags=%lX\n",sb->s_flags);
return sb;
/*
* Begin the cascaded cleanup ...
*/
out_error:
if (root_inode)
iput(root_inode);
if (AFFS_SB->s_bitmap)
kfree(AFFS_SB->s_bitmap);
affs_brelse(root_bh);
if (AFFS_SB->s_prefix)
kfree(AFFS_SB->s_prefix);
return NULL;
}
static int
affs_remount(struct super_block *sb, int *flags, char *data)
{
int blocksize;
uid_t uid;
gid_t gid;
int mode;
int reserved;
int root_block;
unsigned long mount_flags;
unsigned long read_only = AFFS_SB->s_flags & SF_READONLY;
pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data);
if (!parse_options(data,&uid,&gid,&mode,&reserved,&root_block,
&blocksize,&AFFS_SB->s_prefix,AFFS_SB->s_volume,&mount_flags))
return -EINVAL;
AFFS_SB->s_flags = mount_flags | read_only;
AFFS_SB->s_mode = mode;
AFFS_SB->s_uid = uid;
AFFS_SB->s_gid = gid;
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
if (*flags & MS_RDONLY) {
sb->s_dirt = 1;
while (sb->s_dirt)
affs_write_super(sb);
sb->s_flags |= MS_RDONLY;
} else if (!(AFFS_SB->s_flags & SF_READONLY)) {
sb->s_flags &= ~MS_RDONLY;
} else {
affs_warning(sb,"remount","Cannot remount fs read/write because of errors");
return -EINVAL;
}
return 0;
}
static int
affs_statfs(struct super_block *sb, struct statfs *buf)
{
int free;
pr_debug("AFFS: statfs() partsize=%d, reserved=%d\n",AFFS_SB->s_partition_size,
AFFS_SB->s_reserved);
free = affs_count_free_blocks(sb);
buf->f_type = AFFS_SUPER_MAGIC;
buf->f_bsize = sb->s_blocksize;
buf->f_blocks = AFFS_SB->s_partition_size - AFFS_SB->s_reserved;
buf->f_bfree = free;
buf->f_bavail = free;
return 0;
}
static DECLARE_FSTYPE_DEV(affs_fs_type, "affs", affs_read_super);
static int __init init_affs_fs(void)
{
return register_filesystem(&affs_fs_type);
}
static void __exit exit_affs_fs(void)
{
unregister_filesystem(&affs_fs_type);
}
EXPORT_NO_SYMBOLS;
MODULE_DESCRIPTION("Amiga filesystem support for Linux");
MODULE_LICENSE("GPL");
module_init(init_affs_fs)
module_exit(exit_affs_fs)
|