[PATCH] mtd: cmdlinepart: use cmdline partition parser lib
Caizhiyong
caizhiyong at huawei.com
Thu Aug 15 07:19:36 EDT 2013
From: Cai Zhiyong <caizhiyong at huawei.com>
MTD cmdline partition use cmdline partition parser lib
reference: https://lkml.org/lkml/2013/8/6/550
Signed-off-by: Cai ZhiYong <caizhiyong at huawei.com>
---
Documentation/block/cmdline-partition.txt | 93 +++++---
block/cmdline-parser.c | 16 +-
drivers/mtd/Kconfig | 1 +
drivers/mtd/cmdlinepart.c | 361 ++++--------------------------
include/linux/cmdline-parser.h | 8 +-
5 files changed, 111 insertions(+), 368 deletions(-)
diff --git a/Documentation/block/cmdline-partition.txt b/Documentation/block/cmdline-partition.txt
index 651863d..adc5f7a 100644
--- a/Documentation/block/cmdline-partition.txt
+++ b/Documentation/block/cmdline-partition.txt
@@ -1,40 +1,59 @@
Embedded device command line partition
-=====================================================================
-
-Read block device partition table from command line.
-The partition used for fixed block device (eMMC) embedded device.
-It is no MBR, save storage space. Bootloader can be easily accessed
-by absolute address of data on the block device.
-Users can easily change the partition.
-
-The format for the command line is just like mtdparts:
-
-blkdevparts=<blkdev-def>[;<blkdev-def>]
+Authors: Cai Zhiyong <caizhiyong at huawei.com>
+
+The format for the command line is as follows,
+it is used by MTD device (reference drivers/mtd/cmdlinepart.c) and
+block device (reference block/partitions/cmdline.c)
+
+================================================================================
+For MTD device:
+ mtdparts=<mtddef>[;<mtddef]
+ <mtddef> := <mtd-id>:<partdef>[,<partdef>]
+ <partdef> := <size>[@<offset>][<name>][ro][lk]
+ <mtd-id> := unique name used in mapping driver/device (mtd->name)
+ <size> := standard linux memsize OR "-" to denote all remaining space
+ size is automatically truncated at end of device
+ if specified or trucated size is 0 the part is skipped
+ <offset> := standard linux memsize
+ if omitted the part will immediately follow the previous part
+ or 0 if the first part
+ <name> := '(' NAME ')'
+ NAME will appear in /proc/mtd
+
+ <size> and <offset> can be specified such that the parts are out of order
+ in physical memory and may even overlap.
+
+ The parts are assigned MTD numbers in the order they are specified in the
+ command line regardless of their order in physical memory.
+
+ Examples:
+
+ 1 NOR Flash, with 1 single writable partition:
+ edb7312-nor:-
+
+ 1 NOR Flash with 2 partitions, 1 NAND with one
+ edb7312-nor:256k(ARMboot)ro,-(root);edb7312-nand:-(home)
+
+================================================================================
+For block device:
+ blkdevparts=<blkdev-def>[;<blkdev-def>]
<blkdev-def> := <blkdev-id>:<partdef>[,<partdef>]
- <partdef> := <size>[@<offset>](part-name)
-
-<blkdev-id>
- block device disk name, embedded device used fixed block device,
- it's disk name also fixed. such as: mmcblk0, mmcblk1, mmcblk0boot0.
-
-<size>
- partition size, in bytes, such as: 512, 1m, 1G.
-
-<offset>
- partition start address, in bytes.
-
-(part-name)
- partition name, kernel send uevent with "PARTNAME". application can create
- a link to block device partition with the name "PARTNAME".
- user space application can access partition by partition name.
-
-Example:
- eMMC disk name is "mmcblk0" and "mmcblk0boot0"
-
- bootargs:
+ <partdef> := <size>[@<offset>][<name>]
+ <blkdev-id>
+ block device disk name, embedded device used fixed block device,
+ it's disk name also fixed. such as: mmcblk0, mmcblk1, mmcblk0boot0.
+ <size> := standard linux memsize OR "-" to denote all remaining space
+ size is automatically truncated at end of device
+ if specified or trucated size is 0 the part is skipped
+ <offset> := standard linux memsize
+ if omitted the part will immediately follow the previous part
+ or 0 if the first part
+ <name> := '(' NAME ')'
+ partition name, kernel send uevent with "PARTNAME". application could
+ create a link to block device partition with the name "PARTNAME".
+ user space application can access partition by partition name.
+
+ Example:
+
+ eMMC disk name is "mmcblk0" and "mmcblk0boot0", bootargs:
'blkdevparts=mmcblk0:1G(data0),1G(data1),-;mmcblk0boot0:1m(boot),-(kernel)'
-
- dmesg:
- mmcblk0: p1(data0) p2(data1) p3()
- mmcblk0boot0: p1(boot) p2(kernel)
-
diff --git a/block/cmdline-parser.c b/block/cmdline-parser.c
index 18fb435..8c09db3 100644
--- a/block/cmdline-parser.c
+++ b/block/cmdline-parser.c
@@ -4,8 +4,6 @@
* Written by Cai Zhiyong <caizhiyong at 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)
@@ -158,6 +156,7 @@ void cmdline_parts_free(struct cmdline_parts **parts)
*parts = next_parts;
}
}
+EXPORT_SYMBOL(cmdline_parts_free);
int cmdline_parts_parse(struct cmdline_parts **parts, const char *cmdline)
{
@@ -205,6 +204,7 @@ fail:
cmdline_parts_free(parts);
goto done;
}
+EXPORT_SYMBOL(cmdline_parts_parse);
struct cmdline_parts *cmdline_parts_find(struct cmdline_parts *parts,
const char *bdev)
@@ -213,16 +213,17 @@ struct cmdline_parts *cmdline_parts_find(struct cmdline_parts *parts,
parts = parts->next_parts;
return parts;
}
+EXPORT_SYMBOL(cmdline_parts_find);
/*
* 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)
+int 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;
@@ -246,4 +247,7 @@ void cmdline_parts_set(struct cmdline_parts *parts, sector_t disk_size,
if (add_part(slot, subpart, param))
break;
}
+
+ return slot;
}
+EXPORT_SYMBOL(cmdline_parts_set);
diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig
index 5fab4e6e..6f7f9ca 100644
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -75,6 +75,7 @@ endif # MTD_REDBOOT_PARTS
config MTD_CMDLINE_PARTS
tristate "Command line partition table parsing"
+ select CMDLINE_PARSER
depends on MTD
---help---
Allow generic configuration of the MTD partition tables via the kernel
diff --git a/drivers/mtd/cmdlinepart.c b/drivers/mtd/cmdlinepart.c
index 721caeb..79bd584 100644
--- a/drivers/mtd/cmdlinepart.c
+++ b/drivers/mtd/cmdlinepart.c
@@ -18,34 +18,8 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
- * The format for the command line is as follows:
+ * Verbose please reference "Documentation/block/cmdline-partition.txt"
*
- * mtdparts=<mtddef>[;<mtddef]
- * <mtddef> := <mtd-id>:<partdef>[,<partdef>]
- * <partdef> := <size>[@<offset>][<name>][ro][lk]
- * <mtd-id> := unique name used in mapping driver/device (mtd->name)
- * <size> := standard linux memsize OR "-" to denote all remaining space
- * size is automatically truncated at end of device
- * if specified or trucated size is 0 the part is skipped
- * <offset> := standard linux memsize
- * if omitted the part will immediately follow the previous part
- * or 0 if the first part
- * <name> := '(' NAME ')'
- * NAME will appear in /proc/mtd
- *
- * <size> and <offset> can be specified such that the parts are out of order
- * in physical memory and may even overlap.
- *
- * The parts are assigned MTD numbers in the order they are specified in the
- * command line regardless of their order in physical memory.
- *
- * Examples:
- *
- * 1 NOR Flash, with 1 single writable partition:
- * edb7312-nor:-
- *
- * 1 NOR Flash with 2 partitions, 1 NAND with one
- * edb7312-nor:256k(ARMboot)ro,-(root);edb7312-nand:-(home)
*/
#include <linux/kernel.h>
@@ -54,249 +28,43 @@
#include <linux/mtd/partitions.h>
#include <linux/module.h>
#include <linux/err.h>
+#include <linux/cmdline-parser.h>
-/* error message prefix */
-#define ERRP "mtd: "
-
-/* debug macro */
-#if 0
-#define dbg(x) do { printk("DEBUG-CMDLINE-PART: "); printk x; } while(0)
-#else
-#define dbg(x)
-#endif
-
-
-/* special size referring to all the remaining space in a partition */
-#define SIZE_REMAINING ULLONG_MAX
-#define OFFSET_CONTINUOUS ULLONG_MAX
-
-struct cmdline_mtd_partition {
- struct cmdline_mtd_partition *next;
- char *mtd_id;
- int num_parts;
- struct mtd_partition *parts;
-};
-
-/* mtdpart_setup() parses into here */
-static struct cmdline_mtd_partition *partitions;
-
-/* the command line passed to mtdpart_setup() */
static char *mtdparts;
-static char *cmdline;
-static int cmdline_parsed;
+static struct cmdline_parts *mtd_cmdline_parts;
-/*
- * Parse one partition definition for an MTD. Since there can be many
- * comma separated partition definitions, this function calls itself
- * recursively until no more partition definitions are found. Nice side
- * effect: the memory to keep the mtd_partition structs and the names
- * is allocated upon the last definition being found. At that point the
- * syntax has been verified ok.
- */
-static struct mtd_partition * newpart(char *s,
- char **retptr,
- int *num_parts,
- int this_part,
- unsigned char **extra_mem_ptr,
- int extra_mem_size)
+static int add_part(int slot, struct cmdline_subpart *subpart, void *param)
{
- struct mtd_partition *parts;
- unsigned long long size, offset = OFFSET_CONTINUOUS;
- char *name;
- int name_len;
- unsigned char *extra_mem;
- char delim;
- unsigned int mask_flags;
-
- /* fetch the partition size */
- if (*s == '-') {
- /* assign all remaining space to this partition */
- size = SIZE_REMAINING;
- s++;
- } else {
- size = memparse(s, &s);
- if (size < PAGE_SIZE) {
- printk(KERN_ERR ERRP "partition size too small (%llx)\n",
- size);
- return ERR_PTR(-EINVAL);
- }
- }
+ struct mtd_partition *mtdpart = &((struct mtd_partition *)param)[slot];
- /* fetch partition name and flags */
- mask_flags = 0; /* this is going to be a regular partition */
- delim = 0;
+ mtdpart->offset = subpart->from;
+ mtdpart->size = subpart->size;
+ mtdpart->name = subpart->name;
+ mtdpart->mask_flags = 0;
- /* check for offset */
- if (*s == '@') {
- s++;
- offset = memparse(s, &s);
- }
-
- /* now look for name */
- if (*s == '(')
- delim = ')';
-
- if (delim) {
- char *p;
-
- name = ++s;
- p = strchr(name, delim);
- if (!p) {
- printk(KERN_ERR ERRP "no closing %c found in partition name\n", delim);
- return ERR_PTR(-EINVAL);
- }
- name_len = p - name;
- s = p + 1;
- } else {
- name = NULL;
- name_len = 13; /* Partition_000 */
- }
-
- /* record name length for memory allocation later */
- extra_mem_size += name_len + 1;
-
- /* test for options */
- if (strncmp(s, "ro", 2) == 0) {
- mask_flags |= MTD_WRITEABLE;
- s += 2;
- }
+ if (subpart->flags & PF_RDONLY)
+ mtdpart->mask_flags |= MTD_WRITEABLE;
/* if lk is found do NOT unlock the MTD partition*/
- if (strncmp(s, "lk", 2) == 0) {
- mask_flags |= MTD_POWERUP_LOCK;
- s += 2;
- }
-
- /* test if more partitions are following */
- if (*s == ',') {
- if (size == SIZE_REMAINING) {
- printk(KERN_ERR ERRP "no partitions allowed after a fill-up partition\n");
- return ERR_PTR(-EINVAL);
- }
- /* more partitions follow, parse them */
- parts = newpart(s + 1, &s, num_parts, this_part + 1,
- &extra_mem, extra_mem_size);
- if (IS_ERR(parts))
- return parts;
- } else {
- /* this is the last partition: allocate space for all */
- int alloc_size;
-
- *num_parts = this_part + 1;
- alloc_size = *num_parts * sizeof(struct mtd_partition) +
- extra_mem_size;
-
- parts = kzalloc(alloc_size, GFP_KERNEL);
- if (!parts)
- return ERR_PTR(-ENOMEM);
- extra_mem = (unsigned char *)(parts + *num_parts);
- }
-
- /* enter this partition (offset will be calculated later if it is zero at this point) */
- parts[this_part].size = size;
- parts[this_part].offset = offset;
- parts[this_part].mask_flags = mask_flags;
- if (name)
- strlcpy(extra_mem, name, name_len + 1);
- else
- sprintf(extra_mem, "Partition_%03d", this_part);
- parts[this_part].name = extra_mem;
- extra_mem += name_len + 1;
-
- dbg(("partition %d: name <%s>, offset %llx, size %llx, mask flags %x\n",
- this_part, parts[this_part].name, parts[this_part].offset,
- parts[this_part].size, parts[this_part].mask_flags));
+ if (subpart->flags & PF_POWERUP_LOCK)
+ mtdpart->mask_flags |= MTD_POWERUP_LOCK;
- /* return (updated) pointer to extra_mem memory */
- if (extra_mem_ptr)
- *extra_mem_ptr = extra_mem;
-
- /* return (updated) pointer command line string */
- *retptr = s;
-
- /* return partition table */
- return parts;
+ return 0;
}
/*
- * Parse the command line.
+ * This is the handler for our kernel parameter, called from
+ * main.c::checksetup(). Note that we can not yet kmalloc() anything,
+ * so we only save the commandline for later processing.
+ *
+ * This function needs to be visible for bootloaders.
*/
-static int mtdpart_setup_real(char *s)
+static int __init mtdpart_setup(char *s)
{
- cmdline_parsed = 1;
-
- for( ; s != NULL; )
- {
- struct cmdline_mtd_partition *this_mtd;
- struct mtd_partition *parts;
- int mtd_id_len, num_parts;
- char *p, *mtd_id;
-
- mtd_id = s;
-
- /* fetch <mtd-id> */
- p = strchr(s, ':');
- if (!p) {
- printk(KERN_ERR ERRP "no mtd-id\n");
- return -EINVAL;
- }
- mtd_id_len = p - mtd_id;
-
- dbg(("parsing <%s>\n", p+1));
-
- /*
- * parse one mtd. have it reserve memory for the
- * struct cmdline_mtd_partition and the mtd-id string.
- */
- parts = newpart(p + 1, /* cmdline */
- &s, /* out: updated cmdline ptr */
- &num_parts, /* out: number of parts */
- 0, /* first partition */
- (unsigned char**)&this_mtd, /* out: extra mem */
- mtd_id_len + 1 + sizeof(*this_mtd) +
- sizeof(void*)-1 /*alignment*/);
- if (IS_ERR(parts)) {
- /*
- * An error occurred. We're either:
- * a) out of memory, or
- * b) in the middle of the partition spec
- * Either way, this mtd is hosed and we're
- * unlikely to succeed in parsing any more
- */
- return PTR_ERR(parts);
- }
-
- /* align this_mtd */
- this_mtd = (struct cmdline_mtd_partition *)
- ALIGN((unsigned long)this_mtd, sizeof(void *));
- /* enter results */
- this_mtd->parts = parts;
- this_mtd->num_parts = num_parts;
- this_mtd->mtd_id = (char*)(this_mtd + 1);
- strlcpy(this_mtd->mtd_id, mtd_id, mtd_id_len + 1);
-
- /* link into chain */
- this_mtd->next = partitions;
- partitions = this_mtd;
-
- dbg(("mtdid=<%s> num_parts=<%d>\n",
- this_mtd->mtd_id, this_mtd->num_parts));
-
-
- /* EOS - we're done */
- if (*s == 0)
- break;
-
- /* does another spec follow? */
- if (*s != ';') {
- printk(KERN_ERR ERRP "bad character after partition (%c)\n", *s);
- return -EINVAL;
- }
- s++;
- }
-
- return 0;
+ mtdparts = s;
+ return 1;
}
+__setup("mtdparts=", mtdpart_setup);
/*
* Main function to be called from the MTD mapping driver/device to
@@ -309,82 +77,35 @@ static int parse_cmdline_partitions(struct mtd_info *master,
struct mtd_partition **pparts,
struct mtd_part_parser_data *data)
{
- unsigned long long offset;
- int i, err;
- struct cmdline_mtd_partition *part;
- const char *mtd_id = master->name;
+ struct cmdline_parts *parts;
- /* parse command line */
- if (!cmdline_parsed) {
- err = mtdpart_setup_real(cmdline);
- if (err)
- return err;
- }
+ if (mtdparts) {
+ if (mtd_cmdline_parts)
+ cmdline_parts_free(&mtd_cmdline_parts);
+
+ if (cmdline_parts_parse(&mtd_cmdline_parts, mtdparts)) {
+ mtdparts = NULL;
+ return -EINVAL;
+ }
- /*
- * Search for the partition definition matching master->name.
- * If master->name is not set, stop at first partition definition.
- */
- for (part = partitions; part; part = part->next) {
- if ((!mtd_id) || (!strcmp(part->mtd_id, mtd_id)))
- break;
+ mtdparts = NULL;
}
- if (!part)
+ if (!mtd_cmdline_parts)
return 0;
- for (i = 0, offset = 0; i < part->num_parts; i++) {
- if (part->parts[i].offset == OFFSET_CONTINUOUS)
- part->parts[i].offset = offset;
- else
- offset = part->parts[i].offset;
-
- if (part->parts[i].size == SIZE_REMAINING)
- part->parts[i].size = master->size - offset;
-
- if (offset + part->parts[i].size > master->size) {
- printk(KERN_WARNING ERRP
- "%s: partitioning exceeds flash size, truncating\n",
- part->mtd_id);
- part->parts[i].size = master->size - offset;
- }
- offset += part->parts[i].size;
-
- if (part->parts[i].size == 0) {
- printk(KERN_WARNING ERRP
- "%s: skipping zero sized partition\n",
- part->mtd_id);
- part->num_parts--;
- memmove(&part->parts[i], &part->parts[i + 1],
- sizeof(*part->parts) * (part->num_parts - i));
- i--;
- }
- }
+ parts = cmdline_parts_find(mtd_cmdline_parts, master->name);
+ if (!parts)
+ return 0;
- *pparts = kmemdup(part->parts, sizeof(*part->parts) * part->num_parts,
- GFP_KERNEL);
+ *pparts = kzalloc(sizeof(**pparts) * parts->nr_subparts, GFP_KERNEL);
if (!*pparts)
return -ENOMEM;
- return part->num_parts;
-}
-
-
-/*
- * This is the handler for our kernel parameter, called from
- * main.c::checksetup(). Note that we can not yet kmalloc() anything,
- * so we only save the commandline for later processing.
- *
- * This function needs to be visible for bootloaders.
- */
-static int __init mtdpart_setup(char *s)
-{
- cmdline = s;
- return 1;
+ return cmdline_parts_set(parts, master->size, 0, add_part,
+ (void *)*pparts);
}
-__setup("mtdparts=", mtdpart_setup);
-
static struct mtd_part_parser cmdline_parser = {
.owner = THIS_MODULE,
.parse_fn = parse_cmdline_partitions,
@@ -393,8 +114,6 @@ static struct mtd_part_parser cmdline_parser = {
static int __init cmdline_parser_init(void)
{
- if (mtdparts)
- mtdpart_setup(mtdparts);
return register_mtd_parser(&cmdline_parser);
}
diff --git a/include/linux/cmdline-parser.h b/include/linux/cmdline-parser.h
index 98e892e..43b65a9 100644
--- a/include/linux/cmdline-parser.h
+++ b/include/linux/cmdline-parser.h
@@ -35,9 +35,9 @@ int cmdline_parts_parse(struct cmdline_parts **parts, const char *cmdline);
struct cmdline_parts *cmdline_parts_find(struct cmdline_parts *parts,
const char *bdev);
-void cmdline_parts_set(struct cmdline_parts *parts, sector_t disk_size,
- int slot,
- int (*add_part)(int, struct cmdline_subpart *, void *),
- void *param);
+int cmdline_parts_set(struct cmdline_parts *parts, sector_t disk_size,
+ int slot,
+ int (*add_part)(int, struct cmdline_subpart *, void *),
+ void *param);
#endif /* CMDLINEPARSEH */
--
1.8.1.5
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