linux/fs/adfs/super.c

526 lines
12 KiB
C
Raw Normal View History

/*
* linux/fs/adfs/super.c
*
* Copyright (C) 1997-1999 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/buffer_head.h>
#include <linux/parser.h>
#include <linux/mount.h>
#include <linux/seq_file.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/statfs.h>
#include "adfs.h"
#include "dir_f.h"
#include "dir_fplus.h"
#define ADFS_DEFAULT_OWNER_MASK S_IRWXU
#define ADFS_DEFAULT_OTHER_MASK (S_IRWXG | S_IRWXO)
void __adfs_error(struct super_block *sb, const char *function, const char *fmt, ...)
{
char error_buf[128];
va_list args;
va_start(args, fmt);
vsnprintf(error_buf, sizeof(error_buf), fmt, args);
va_end(args);
printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %s\n",
sb->s_id, function ? ": " : "",
function ? function : "", error_buf);
}
static int adfs_checkdiscrecord(struct adfs_discrecord *dr)
{
int i;
/* sector size must be 256, 512 or 1024 bytes */
if (dr->log2secsize != 8 &&
dr->log2secsize != 9 &&
dr->log2secsize != 10)
return 1;
/* idlen must be at least log2secsize + 3 */
if (dr->idlen < dr->log2secsize + 3)
return 1;
/* we cannot have such a large disc that we
* are unable to represent sector offsets in
* 32 bits. This works out at 2.0 TB.
*/
if (le32_to_cpu(dr->disc_size_high) >> dr->log2secsize)
return 1;
/* idlen must be no greater than 19 v2 [1.0] */
if (dr->idlen > 19)
return 1;
/* reserved bytes should be zero */
for (i = 0; i < sizeof(dr->unused52); i++)
if (dr->unused52[i] != 0)
return 1;
return 0;
}
static unsigned char adfs_calczonecheck(struct super_block *sb, unsigned char *map)
{
unsigned int v0, v1, v2, v3;
int i;
v0 = v1 = v2 = v3 = 0;
for (i = sb->s_blocksize - 4; i; i -= 4) {
v0 += map[i] + (v3 >> 8);
v3 &= 0xff;
v1 += map[i + 1] + (v0 >> 8);
v0 &= 0xff;
v2 += map[i + 2] + (v1 >> 8);
v1 &= 0xff;
v3 += map[i + 3] + (v2 >> 8);
v2 &= 0xff;
}
v0 += v3 >> 8;
v1 += map[1] + (v0 >> 8);
v2 += map[2] + (v1 >> 8);
v3 += map[3] + (v2 >> 8);
return v0 ^ v1 ^ v2 ^ v3;
}
static int adfs_checkmap(struct super_block *sb, struct adfs_discmap *dm)
{
unsigned char crosscheck = 0, zonecheck = 1;
int i;
for (i = 0; i < ADFS_SB(sb)->s_map_size; i++) {
unsigned char *map;
map = dm[i].dm_bh->b_data;
if (adfs_calczonecheck(sb, map) != map[0]) {
adfs_error(sb, "zone %d fails zonecheck", i);
zonecheck = 0;
}
crosscheck ^= map[3];
}
if (crosscheck != 0xff)
adfs_error(sb, "crosscheck != 0xff");
return crosscheck == 0xff && zonecheck;
}
static void adfs_put_super(struct super_block *sb)
{
int i;
struct adfs_sb_info *asb = ADFS_SB(sb);
lock_kernel();
for (i = 0; i < asb->s_map_size; i++)
brelse(asb->s_map[i].dm_bh);
kfree(asb->s_map);
kfree(asb);
sb->s_fs_info = NULL;
unlock_kernel();
}
static int adfs_show_options(struct seq_file *seq, struct vfsmount *mnt)
{
struct adfs_sb_info *asb = ADFS_SB(mnt->mnt_sb);
if (asb->s_uid != 0)
seq_printf(seq, ",uid=%u", asb->s_uid);
if (asb->s_gid != 0)
seq_printf(seq, ",gid=%u", asb->s_gid);
if (asb->s_owner_mask != ADFS_DEFAULT_OWNER_MASK)
seq_printf(seq, ",ownmask=%o", asb->s_owner_mask);
if (asb->s_other_mask != ADFS_DEFAULT_OTHER_MASK)
seq_printf(seq, ",othmask=%o", asb->s_other_mask);
return 0;
}
enum {Opt_uid, Opt_gid, Opt_ownmask, Opt_othmask, Opt_err};
static const match_table_t tokens = {
{Opt_uid, "uid=%u"},
{Opt_gid, "gid=%u"},
{Opt_ownmask, "ownmask=%o"},
{Opt_othmask, "othmask=%o"},
{Opt_err, NULL}
};
static int parse_options(struct super_block *sb, char *options)
{
char *p;
struct adfs_sb_info *asb = ADFS_SB(sb);
int option;
if (!options)
return 0;
while ((p = strsep(&options, ",")) != NULL) {
substring_t args[MAX_OPT_ARGS];
int token;
if (!*p)
continue;
token = match_token(p, tokens, args);
switch (token) {
case Opt_uid:
if (match_int(args, &option))
return -EINVAL;
asb->s_uid = option;
break;
case Opt_gid:
if (match_int(args, &option))
return -EINVAL;
asb->s_gid = option;
break;
case Opt_ownmask:
if (match_octal(args, &option))
return -EINVAL;
asb->s_owner_mask = option;
break;
case Opt_othmask:
if (match_octal(args, &option))
return -EINVAL;
asb->s_other_mask = option;
break;
default:
printk("ADFS-fs: unrecognised mount option \"%s\" "
"or missing value\n", p);
return -EINVAL;
}
}
return 0;
}
static int adfs_remount(struct super_block *sb, int *flags, char *data)
{
*flags |= MS_NODIRATIME;
return parse_options(sb, data);
}
static int adfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = dentry->d_sb;
struct adfs_sb_info *sbi = ADFS_SB(sb);
u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
buf->f_type = ADFS_SUPER_MAGIC;
buf->f_namelen = sbi->s_namelen;
buf->f_bsize = sb->s_blocksize;
buf->f_blocks = sbi->s_size;
buf->f_files = sbi->s_ids_per_zone * sbi->s_map_size;
buf->f_bavail =
buf->f_bfree = adfs_map_free(sb);
buf->f_ffree = (long)(buf->f_bfree * buf->f_files) / (long)buf->f_blocks;
buf->f_fsid.val[0] = (u32)id;
buf->f_fsid.val[1] = (u32)(id >> 32);
return 0;
}
static struct kmem_cache *adfs_inode_cachep;
static struct inode *adfs_alloc_inode(struct super_block *sb)
{
struct adfs_inode_info *ei;
ei = (struct adfs_inode_info *)kmem_cache_alloc(adfs_inode_cachep, GFP_KERNEL);
if (!ei)
return NULL;
return &ei->vfs_inode;
}
static void adfs_destroy_inode(struct inode *inode)
{
kmem_cache_free(adfs_inode_cachep, ADFS_I(inode));
}
static void init_once(void *foo)
{
struct adfs_inode_info *ei = (struct adfs_inode_info *) foo;
inode_init_once(&ei->vfs_inode);
}
static int init_inodecache(void)
{
adfs_inode_cachep = kmem_cache_create("adfs_inode_cache",
sizeof(struct adfs_inode_info),
0, (SLAB_RECLAIM_ACCOUNT|
SLAB_MEM_SPREAD),
init_once);
if (adfs_inode_cachep == NULL)
return -ENOMEM;
return 0;
}
static void destroy_inodecache(void)
{
kmem_cache_destroy(adfs_inode_cachep);
}
static const struct super_operations adfs_sops = {
.alloc_inode = adfs_alloc_inode,
.destroy_inode = adfs_destroy_inode,
.write_inode = adfs_write_inode,
.put_super = adfs_put_super,
.statfs = adfs_statfs,
.remount_fs = adfs_remount,
.show_options = adfs_show_options,
};
static struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr)
{
struct adfs_discmap *dm;
unsigned int map_addr, zone_size, nzones;
int i, zone;
struct adfs_sb_info *asb = ADFS_SB(sb);
nzones = asb->s_map_size;
zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare);
map_addr = (nzones >> 1) * zone_size -
((nzones > 1) ? ADFS_DR_SIZE_BITS : 0);
map_addr = signed_asl(map_addr, asb->s_map2blk);
asb->s_ids_per_zone = zone_size / (asb->s_idlen + 1);
dm = kmalloc(nzones * sizeof(*dm), GFP_KERNEL);
if (dm == NULL) {
adfs_error(sb, "not enough memory");
return NULL;
}
for (zone = 0; zone < nzones; zone++, map_addr++) {
dm[zone].dm_startbit = 0;
dm[zone].dm_endbit = zone_size;
dm[zone].dm_startblk = zone * zone_size - ADFS_DR_SIZE_BITS;
dm[zone].dm_bh = sb_bread(sb, map_addr);
if (!dm[zone].dm_bh) {
adfs_error(sb, "unable to read map");
goto error_free;
}
}
/* adjust the limits for the first and last map zones */
i = zone - 1;
dm[0].dm_startblk = 0;
dm[0].dm_startbit = ADFS_DR_SIZE_BITS;
dm[i].dm_endbit = (le32_to_cpu(dr->disc_size_high) << (32 - dr->log2bpmb)) +
(le32_to_cpu(dr->disc_size) >> dr->log2bpmb) +
(ADFS_DR_SIZE_BITS - i * zone_size);
if (adfs_checkmap(sb, dm))
return dm;
adfs_error(sb, "map corrupted");
error_free:
while (--zone >= 0)
brelse(dm[zone].dm_bh);
kfree(dm);
return NULL;
}
static inline unsigned long adfs_discsize(struct adfs_discrecord *dr, int block_bits)
{
unsigned long discsize;
discsize = le32_to_cpu(dr->disc_size_high) << (32 - block_bits);
discsize |= le32_to_cpu(dr->disc_size) >> block_bits;
return discsize;
}
static int adfs_fill_super(struct super_block *sb, void *data, int silent)
{
struct adfs_discrecord *dr;
struct buffer_head *bh;
struct object_info root_obj;
unsigned char *b_data;
struct adfs_sb_info *asb;
struct inode *root;
sb->s_flags |= MS_NODIRATIME;
asb = kzalloc(sizeof(*asb), GFP_KERNEL);
if (!asb)
return -ENOMEM;
sb->s_fs_info = asb;
/* set default options */
asb->s_uid = 0;
asb->s_gid = 0;
asb->s_owner_mask = ADFS_DEFAULT_OWNER_MASK;
asb->s_other_mask = ADFS_DEFAULT_OTHER_MASK;
if (parse_options(sb, data))
goto error;
sb_set_blocksize(sb, BLOCK_SIZE);
if (!(bh = sb_bread(sb, ADFS_DISCRECORD / BLOCK_SIZE))) {
adfs_error(sb, "unable to read superblock");
goto error;
}
b_data = bh->b_data + (ADFS_DISCRECORD % BLOCK_SIZE);
if (adfs_checkbblk(b_data)) {
if (!silent)
printk("VFS: Can't find an adfs filesystem on dev "
"%s.\n", sb->s_id);
goto error_free_bh;
}
dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET);
/*
* Do some sanity checks on the ADFS disc record
*/
if (adfs_checkdiscrecord(dr)) {
if (!silent)
printk("VPS: Can't find an adfs filesystem on dev "
"%s.\n", sb->s_id);
goto error_free_bh;
}
brelse(bh);
if (sb_set_blocksize(sb, 1 << dr->log2secsize)) {
bh = sb_bread(sb, ADFS_DISCRECORD / sb->s_blocksize);
if (!bh) {
adfs_error(sb, "couldn't read superblock on "
"2nd try.");
goto error;
}
b_data = bh->b_data + (ADFS_DISCRECORD % sb->s_blocksize);
if (adfs_checkbblk(b_data)) {
adfs_error(sb, "disc record mismatch, very weird!");
goto error_free_bh;
}
dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET);
} else {
if (!silent)
printk(KERN_ERR "VFS: Unsupported blocksize on dev "
"%s.\n", sb->s_id);
goto error;
}
/*
* blocksize on this device should now be set to the ADFS log2secsize
*/
sb->s_magic = ADFS_SUPER_MAGIC;
asb->s_idlen = dr->idlen;
asb->s_map_size = dr->nzones | (dr->nzones_high << 8);
asb->s_map2blk = dr->log2bpmb - dr->log2secsize;
asb->s_size = adfs_discsize(dr, sb->s_blocksize_bits);
asb->s_version = dr->format_version;
asb->s_log2sharesize = dr->log2sharesize;
asb->s_map = adfs_read_map(sb, dr);
if (!asb->s_map)
goto error_free_bh;
brelse(bh);
/*
* set up enough so that we can read an inode
*/
sb->s_op = &adfs_sops;
dr = (struct adfs_discrecord *)(asb->s_map[0].dm_bh->b_data + 4);
root_obj.parent_id = root_obj.file_id = le32_to_cpu(dr->root);
root_obj.name_len = 0;
root_obj.loadaddr = 0;
root_obj.execaddr = 0;
root_obj.size = ADFS_NEWDIR_SIZE;
root_obj.attr = ADFS_NDA_DIRECTORY | ADFS_NDA_OWNER_READ |
ADFS_NDA_OWNER_WRITE | ADFS_NDA_PUBLIC_READ;
/*
* If this is a F+ disk with variable length directories,
* get the root_size from the disc record.
*/
if (asb->s_version) {
root_obj.size = le32_to_cpu(dr->root_size);
asb->s_dir = &adfs_fplus_dir_ops;
asb->s_namelen = ADFS_FPLUS_NAME_LEN;
} else {
asb->s_dir = &adfs_f_dir_ops;
asb->s_namelen = ADFS_F_NAME_LEN;
}
root = adfs_iget(sb, &root_obj);
sb->s_root = d_alloc_root(root);
if (!sb->s_root) {
int i;
iput(root);
for (i = 0; i < asb->s_map_size; i++)
brelse(asb->s_map[i].dm_bh);
kfree(asb->s_map);
adfs_error(sb, "get root inode failed\n");
goto error;
} else
sb->s_root->d_op = &adfs_dentry_operations;
return 0;
error_free_bh:
brelse(bh);
error:
sb->s_fs_info = NULL;
kfree(asb);
return -EINVAL;
}
[PATCH] VFS: Permit filesystem to override root dentry on mount Extend the get_sb() filesystem operation to take an extra argument that permits the VFS to pass in the target vfsmount that defines the mountpoint. The filesystem is then required to manually set the superblock and root dentry pointers. For most filesystems, this should be done with simple_set_mnt() which will set the superblock pointer and then set the root dentry to the superblock's s_root (as per the old default behaviour). The get_sb() op now returns an integer as there's now no need to return the superblock pointer. This patch permits a superblock to be implicitly shared amongst several mount points, such as can be done with NFS to avoid potential inode aliasing. In such a case, simple_set_mnt() would not be called, and instead the mnt_root and mnt_sb would be set directly. The patch also makes the following changes: (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount pointer argument and return an integer, so most filesystems have to change very little. (*) If one of the convenience function is not used, then get_sb() should normally call simple_set_mnt() to instantiate the vfsmount. This will always return 0, and so can be tail-called from get_sb(). (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the dcache upon superblock destruction rather than shrink_dcache_anon(). This is required because the superblock may now have multiple trees that aren't actually bound to s_root, but that still need to be cleaned up. The currently called functions assume that the whole tree is rooted at s_root, and that anonymous dentries are not the roots of trees which results in dentries being left unculled. However, with the way NFS superblock sharing are currently set to be implemented, these assumptions are violated: the root of the filesystem is simply a dummy dentry and inode (the real inode for '/' may well be inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries with child trees. [*] Anonymous until discovered from another tree. (*) The documentation has been adjusted, including the additional bit of changing ext2_* into foo_* in the documentation. [akpm@osdl.org: convert ipath_fs, do other stuff] Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Nathan Scott <nathans@sgi.com> Cc: Roland Dreier <rolandd@cisco.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 09:02:57 +00:00
static int adfs_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
[PATCH] VFS: Permit filesystem to override root dentry on mount Extend the get_sb() filesystem operation to take an extra argument that permits the VFS to pass in the target vfsmount that defines the mountpoint. The filesystem is then required to manually set the superblock and root dentry pointers. For most filesystems, this should be done with simple_set_mnt() which will set the superblock pointer and then set the root dentry to the superblock's s_root (as per the old default behaviour). The get_sb() op now returns an integer as there's now no need to return the superblock pointer. This patch permits a superblock to be implicitly shared amongst several mount points, such as can be done with NFS to avoid potential inode aliasing. In such a case, simple_set_mnt() would not be called, and instead the mnt_root and mnt_sb would be set directly. The patch also makes the following changes: (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount pointer argument and return an integer, so most filesystems have to change very little. (*) If one of the convenience function is not used, then get_sb() should normally call simple_set_mnt() to instantiate the vfsmount. This will always return 0, and so can be tail-called from get_sb(). (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the dcache upon superblock destruction rather than shrink_dcache_anon(). This is required because the superblock may now have multiple trees that aren't actually bound to s_root, but that still need to be cleaned up. The currently called functions assume that the whole tree is rooted at s_root, and that anonymous dentries are not the roots of trees which results in dentries being left unculled. However, with the way NFS superblock sharing are currently set to be implemented, these assumptions are violated: the root of the filesystem is simply a dummy dentry and inode (the real inode for '/' may well be inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries with child trees. [*] Anonymous until discovered from another tree. (*) The documentation has been adjusted, including the additional bit of changing ext2_* into foo_* in the documentation. [akpm@osdl.org: convert ipath_fs, do other stuff] Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Nathan Scott <nathans@sgi.com> Cc: Roland Dreier <rolandd@cisco.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 09:02:57 +00:00
return get_sb_bdev(fs_type, flags, dev_name, data, adfs_fill_super,
mnt);
}
static struct file_system_type adfs_fs_type = {
.owner = THIS_MODULE,
.name = "adfs",
.get_sb = adfs_get_sb,
.kill_sb = kill_block_super,
.fs_flags = FS_REQUIRES_DEV,
};
static int __init init_adfs_fs(void)
{
int err = init_inodecache();
if (err)
goto out1;
err = register_filesystem(&adfs_fs_type);
if (err)
goto out;
return 0;
out:
destroy_inodecache();
out1:
return err;
}
static void __exit exit_adfs_fs(void)
{
unregister_filesystem(&adfs_fs_type);
destroy_inodecache();
}
module_init(init_adfs_fs)
module_exit(exit_adfs_fs)
MODULE_LICENSE("GPL");