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/*
* Parse command line, get partition information
*
* Written by Cai Zhiyong <caizhiyong@huawei.com>
*
*/
#include <linux/buffer_head.h>
#include <linux/module.h>
#include <linux/cmdline-parser.h>
static int parse_subpart(struct cmdline_subpart **subpart, char *partdef)
{
int ret = 0;
struct cmdline_subpart *new_subpart;
*subpart = NULL;
new_subpart = kzalloc(sizeof(struct cmdline_subpart), GFP_KERNEL);
if (!new_subpart)
return -ENOMEM;
if (*partdef == '-') {
new_subpart->size = (sector_t)(~0ULL);
partdef++;
} else {
new_subpart->size = (sector_t)memparse(partdef, &partdef);
if (new_subpart->size < (sector_t)PAGE_SIZE) {
pr_warn("cmdline partition size is invalid.");
ret = -EINVAL;
goto fail;
}
}
if (*partdef == '@') {
partdef++;
new_subpart->from = (sector_t)memparse(partdef, &partdef);
} else {
new_subpart->from = (sector_t)(~0ULL);
}
if (*partdef == '(') {
int length;
char *next = strchr(++partdef, ')');
if (!next) {
pr_warn("cmdline partition format is invalid.");
ret = -EINVAL;
goto fail;
}
length = min_t(int, next - partdef,
sizeof(new_subpart->name) - 1);
strncpy(new_subpart->name, partdef, length);
new_subpart->name[length] = '\0';
partdef = ++next;
} else
new_subpart->name[0] = '\0';
new_subpart->flags = 0;
if (!strncmp(partdef, "ro", 2)) {
new_subpart->flags |= PF_RDONLY;
partdef += 2;
}
if (!strncmp(partdef, "lk", 2)) {
new_subpart->flags |= PF_POWERUP_LOCK;
partdef += 2;
}
*subpart = new_subpart;
return 0;
fail:
kfree(new_subpart);
return ret;
}
static void free_subpart(struct cmdline_parts *parts)
{
struct cmdline_subpart *subpart;
while (parts->subpart) {
subpart = parts->subpart;
parts->subpart = subpart->next_subpart;
kfree(subpart);
}
}
static int parse_parts(struct cmdline_parts **parts, const char *bdevdef)
{
int ret = -EINVAL;
char *next;
int length;
struct cmdline_subpart **next_subpart;
struct cmdline_parts *newparts;
char buf[BDEVNAME_SIZE + 32 + 4];
*parts = NULL;
newparts = kzalloc(sizeof(struct cmdline_parts), GFP_KERNEL);
if (!newparts)
return -ENOMEM;
next = strchr(bdevdef, ':');
if (!next) {
pr_warn("cmdline partition has no block device.");
goto fail;
}
length = min_t(int, next - bdevdef, sizeof(newparts->name) - 1);
strncpy(newparts->name, bdevdef, length);
newparts->name[length] = '\0';
newparts->nr_subparts = 0;
next_subpart = &newparts->subpart;
while (next && *(++next)) {
bdevdef = next;
next = strchr(bdevdef, ',');
length = (!next) ? (sizeof(buf) - 1) :
min_t(int, next - bdevdef, sizeof(buf) - 1);
strncpy(buf, bdevdef, length);
buf[length] = '\0';
ret = parse_subpart(next_subpart, buf);
if (ret)
goto fail;
newparts->nr_subparts++;
next_subpart = &(*next_subpart)->next_subpart;
}
if (!newparts->subpart) {
pr_warn("cmdline partition has no valid partition.");
ret = -EINVAL;
goto fail;
}
*parts = newparts;
return 0;
fail:
free_subpart(newparts);
kfree(newparts);
return ret;
}
void cmdline_parts_free(struct cmdline_parts **parts)
{
struct cmdline_parts *next_parts;
while (*parts) {
next_parts = (*parts)->next_parts;
free_subpart(*parts);
kfree(*parts);
*parts = next_parts;
}
}
int cmdline_parts_parse(struct cmdline_parts **parts, const char *cmdline)
{
int ret;
char *buf;
char *pbuf;
char *next;
struct cmdline_parts **next_parts;
*parts = NULL;
next = pbuf = buf = kstrdup(cmdline, GFP_KERNEL);
if (!buf)
return -ENOMEM;
next_parts = parts;
while (next && *pbuf) {
next = strchr(pbuf, ';');
if (next)
*next = '\0';
ret = parse_parts(next_parts, pbuf);
if (ret)
goto fail;
if (next)
pbuf = ++next;
next_parts = &(*next_parts)->next_parts;
}
if (!*parts) {
pr_warn("cmdline partition has no valid partition.");
ret = -EINVAL;
goto fail;
}
ret = 0;
done:
kfree(buf);
return ret;
fail:
cmdline_parts_free(parts);
goto done;
}
struct cmdline_parts *cmdline_parts_find(struct cmdline_parts *parts,
const char *bdev)
{
while (parts && strncmp(bdev, parts->name, sizeof(parts->name)))
parts = parts->next_parts;
return parts;
}
/*
* add_part()
* 0 success.
* 1 can not add so many partitions.
*/
void cmdline_parts_set(struct cmdline_parts *parts, sector_t disk_size,
int slot,
int (*add_part)(int, struct cmdline_subpart *, void *),
void *param)
{
sector_t from = 0;
struct cmdline_subpart *subpart;
for (subpart = parts->subpart; subpart;
subpart = subpart->next_subpart, slot++) {
if (subpart->from == (sector_t)(~0ULL))
subpart->from = from;
else
from = subpart->from;
if (from >= disk_size)
break;
if (subpart->size > (disk_size - from))
subpart->size = disk_size - from;
from += subpart->size;
if (add_part(slot, subpart, param))
break;
}
}
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