Commit e73a75fa authored by Randy Dunlap's avatar Randy Dunlap Committed by Linus Torvalds

hugetlbfs: use lib/parser, fix docs

Use lib/parser.c to parse hugetlbfs mount options.  Correct docs in
hugetlbpage.txt.

old size of hugetlbfs_fill_super:  675 bytes
new size of hugetlbfs_fill_super:  686 bytes
(hugetlbfs_parse_options() is inlined)
Signed-off-by: default avatarRandy Dunlap <randy.dunlap@oracle.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Adam Litke <agl@us.ibm.com>
Acked-by: default avatarWilliam Lee Irwin III <wli@holomorphy.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 52161845
......@@ -77,8 +77,9 @@ If the user applications are going to request hugepages using mmap system
call, then it is required that system administrator mount a file system of
type hugetlbfs:
mount none /mnt/huge -t hugetlbfs <uid=value> <gid=value> <mode=value>
<size=value> <nr_inodes=value>
mount -t hugetlbfs \
-o uid=<value>,gid=<value>,mode=<value>,size=<value>,nr_inodes=<value> \
none /mnt/huge
This command mounts a (pseudo) filesystem of type hugetlbfs on the directory
/mnt/huge. Any files created on /mnt/huge uses hugepages. The uid and gid
......@@ -88,11 +89,10 @@ mode of root of file system to value & 0777. This value is given in octal.
By default the value 0755 is picked. The size option sets the maximum value of
memory (huge pages) allowed for that filesystem (/mnt/huge). The size is
rounded down to HPAGE_SIZE. The option nr_inodes sets the maximum number of
inodes that /mnt/huge can use. If the size or nr_inodes options are not
inodes that /mnt/huge can use. If the size or nr_inodes option is not
provided on command line then no limits are set. For size and nr_inodes
options, you can use [G|g]/[M|m]/[K|k] to represent giga/mega/kilo. For
example, size=2K has the same meaning as size=2048. An example is given at
the end of this document.
example, size=2K has the same meaning as size=2048.
read and write system calls are not supported on files that reside on hugetlb
file systems.
......
......@@ -13,15 +13,18 @@
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/file.h>
#include <linux/kernel.h>
#include <linux/writeback.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/capability.h>
#include <linux/ctype.h>
#include <linux/backing-dev.h>
#include <linux/hugetlb.h>
#include <linux/pagevec.h>
#include <linux/parser.h>
#include <linux/mman.h>
#include <linux/quotaops.h>
#include <linux/slab.h>
......@@ -47,6 +50,21 @@ static struct backing_dev_info hugetlbfs_backing_dev_info = {
int sysctl_hugetlb_shm_group;
enum {
Opt_size, Opt_nr_inodes,
Opt_mode, Opt_uid, Opt_gid,
Opt_err,
};
static match_table_t tokens = {
{Opt_size, "size=%s"},
{Opt_nr_inodes, "nr_inodes=%s"},
{Opt_mode, "mode=%o"},
{Opt_uid, "uid=%u"},
{Opt_gid, "gid=%u"},
{Opt_err, NULL},
};
static void huge_pagevec_release(struct pagevec *pvec)
{
int i;
......@@ -594,46 +612,70 @@ static const struct super_operations hugetlbfs_ops = {
static int
hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig)
{
char *opt, *value, *rest;
char *p, *rest;
substring_t args[MAX_OPT_ARGS];
int option;
if (!options)
return 0;
while ((opt = strsep(&options, ",")) != NULL) {
if (!*opt)
continue;
value = strchr(opt, '=');
if (!value || !*value)
return -EINVAL;
else
*value++ = '\0';
if (!strcmp(opt, "uid"))
pconfig->uid = simple_strtoul(value, &value, 0);
else if (!strcmp(opt, "gid"))
pconfig->gid = simple_strtoul(value, &value, 0);
else if (!strcmp(opt, "mode"))
pconfig->mode = simple_strtoul(value,&value,0) & 0777U;
else if (!strcmp(opt, "size")) {
unsigned long long size = memparse(value, &rest);
while ((p = strsep(&options, ",")) != NULL) {
int token;
token = match_token(p, tokens, args);
switch (token) {
case Opt_uid:
if (match_int(&args[0], &option))
goto bad_val;
pconfig->uid = option;
break;
case Opt_gid:
if (match_int(&args[0], &option))
goto bad_val;
pconfig->gid = option;
break;
case Opt_mode:
if (match_octal(&args[0], &option))
goto bad_val;
pconfig->mode = option & 0777U;
break;
case Opt_size: {
unsigned long long size;
/* memparse() will accept a K/M/G without a digit */
if (!isdigit(*args[0].from))
goto bad_val;
size = memparse(args[0].from, &rest);
if (*rest == '%') {
size <<= HPAGE_SHIFT;
size *= max_huge_pages;
do_div(size, 100);
rest++;
}
pconfig->nr_blocks = (size >> HPAGE_SHIFT);
value = rest;
} else if (!strcmp(opt,"nr_inodes")) {
pconfig->nr_inodes = memparse(value, &rest);
value = rest;
} else
return -EINVAL;
break;
}
if (*value)
return -EINVAL;
case Opt_nr_inodes:
/* memparse() will accept a K/M/G without a digit */
if (!isdigit(*args[0].from))
goto bad_val;
pconfig->nr_inodes = memparse(args[0].from, &rest);
break;
default:
printk(KERN_ERR "hugetlbfs: Bad mount option: %s\n", p);
return 1;
break;
}
}
return 0;
bad_val:
printk(KERN_ERR "hugetlbfs: Bad value '%s' for mount option '%s'\n",
args[0].from, p);
return 1;
}
static int
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment