linux/fs/hfsplus/options.c
Christoph Hellwig 84adede312 hfsplus: use atomic bitops for the superblock flags
The flags in the HFS+-specific superlock do get modified during runtime,
use atomic bitops to make the modifications SMP safe.

Signed-off-by: Christoph Hellwig <hch@tuxera.com>
2010-10-01 05:45:20 +02:00

191 lines
4.4 KiB
C

/*
* linux/fs/hfsplus/options.c
*
* Copyright (C) 2001
* Brad Boyer (flar@allandria.com)
* (C) 2003 Ardis Technologies <roman@ardistech.com>
*
* Option parsing
*/
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/parser.h>
#include <linux/nls.h>
#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include "hfsplus_fs.h"
enum {
opt_creator, opt_type,
opt_umask, opt_uid, opt_gid,
opt_part, opt_session, opt_nls,
opt_nodecompose, opt_decompose,
opt_force, opt_err
};
static const match_table_t tokens = {
{ opt_creator, "creator=%s" },
{ opt_type, "type=%s" },
{ opt_umask, "umask=%o" },
{ opt_uid, "uid=%u" },
{ opt_gid, "gid=%u" },
{ opt_part, "part=%u" },
{ opt_session, "session=%u" },
{ opt_nls, "nls=%s" },
{ opt_decompose, "decompose" },
{ opt_nodecompose, "nodecompose" },
{ opt_force, "force" },
{ opt_err, NULL }
};
/* Initialize an options object to reasonable defaults */
void hfsplus_fill_defaults(struct hfsplus_sb_info *opts)
{
if (!opts)
return;
opts->creator = HFSPLUS_DEF_CR_TYPE;
opts->type = HFSPLUS_DEF_CR_TYPE;
opts->umask = current_umask();
opts->uid = current_uid();
opts->gid = current_gid();
opts->part = -1;
opts->session = -1;
}
/* convert a "four byte character" to a 32 bit int with error checks */
static inline int match_fourchar(substring_t *arg, u32 *result)
{
if (arg->to - arg->from != 4)
return -EINVAL;
memcpy(result, arg->from, 4);
return 0;
}
/* Parse options from mount. Returns 0 on failure */
/* input is the options passed to mount() as a string */
int hfsplus_parse_options(char *input, struct hfsplus_sb_info *sbi)
{
char *p;
substring_t args[MAX_OPT_ARGS];
int tmp, token;
if (!input)
goto done;
while ((p = strsep(&input, ",")) != NULL) {
if (!*p)
continue;
token = match_token(p, tokens, args);
switch (token) {
case opt_creator:
if (match_fourchar(&args[0], &sbi->creator)) {
printk(KERN_ERR "hfs: creator requires a 4 character value\n");
return 0;
}
break;
case opt_type:
if (match_fourchar(&args[0], &sbi->type)) {
printk(KERN_ERR "hfs: type requires a 4 character value\n");
return 0;
}
break;
case opt_umask:
if (match_octal(&args[0], &tmp)) {
printk(KERN_ERR "hfs: umask requires a value\n");
return 0;
}
sbi->umask = (umode_t)tmp;
break;
case opt_uid:
if (match_int(&args[0], &tmp)) {
printk(KERN_ERR "hfs: uid requires an argument\n");
return 0;
}
sbi->uid = (uid_t)tmp;
break;
case opt_gid:
if (match_int(&args[0], &tmp)) {
printk(KERN_ERR "hfs: gid requires an argument\n");
return 0;
}
sbi->gid = (gid_t)tmp;
break;
case opt_part:
if (match_int(&args[0], &sbi->part)) {
printk(KERN_ERR "hfs: part requires an argument\n");
return 0;
}
break;
case opt_session:
if (match_int(&args[0], &sbi->session)) {
printk(KERN_ERR "hfs: session requires an argument\n");
return 0;
}
break;
case opt_nls:
if (sbi->nls) {
printk(KERN_ERR "hfs: unable to change nls mapping\n");
return 0;
}
p = match_strdup(&args[0]);
if (p)
sbi->nls = load_nls(p);
if (!sbi->nls) {
printk(KERN_ERR "hfs: unable to load nls mapping \"%s\"\n", p);
kfree(p);
return 0;
}
kfree(p);
break;
case opt_decompose:
clear_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags);
break;
case opt_nodecompose:
set_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags);
break;
case opt_force:
set_bit(HFSPLUS_SB_FORCE, &sbi->flags);
break;
default:
return 0;
}
}
done:
if (!sbi->nls) {
/* try utf8 first, as this is the old default behaviour */
sbi->nls = load_nls("utf8");
if (!sbi->nls)
sbi->nls = load_nls_default();
if (!sbi->nls)
return 0;
}
return 1;
}
int hfsplus_show_options(struct seq_file *seq, struct vfsmount *mnt)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(mnt->mnt_sb);
if (sbi->creator != HFSPLUS_DEF_CR_TYPE)
seq_printf(seq, ",creator=%.4s", (char *)&sbi->creator);
if (sbi->type != HFSPLUS_DEF_CR_TYPE)
seq_printf(seq, ",type=%.4s", (char *)&sbi->type);
seq_printf(seq, ",umask=%o,uid=%u,gid=%u", sbi->umask, sbi->uid, sbi->gid);
if (sbi->part >= 0)
seq_printf(seq, ",part=%u", sbi->part);
if (sbi->session >= 0)
seq_printf(seq, ",session=%u", sbi->session);
if (sbi->nls)
seq_printf(seq, ",nls=%s", sbi->nls->charset);
if (test_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags))
seq_printf(seq, ",nodecompose");
return 0;
}