[PATCH 2/2] mtd: cmdlinepart: use cmdline partition parser lib

From: Caizhiyong
Date: Tue Oct 22 2013 - 09:15:43 EST

From: CaiZhiyong <caizhiyong@xxxxxxxxxx>
Subject: mtd: cmdlinepart: use cmdline partition parser lib

In the previous version, adjust the cmdline parser code to library-style
code, and move it to a separate file "block/cmdline-parser.c", we can use
it in some client code. there is no any functionality change in the adjusting.

this patch use cmdline parser lib.

For further information, see "https://lkml.org/lkml/2013/8/6/550";

Signed-off-by: CaiZhiyong <caizhiyong@xxxxxxxxxx>
---
drivers/mtd/Kconfig | 1 +
drivers/mtd/cmdlinepart.c | 343 +++++-----------------------------------------
2 files changed, 39 insertions(+), 305 deletions(-)

diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig
index 5fab4e6e..daf544a 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 BLK_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..ba934a4 100644
--- a/drivers/mtd/cmdlinepart.c
+++ b/drivers/mtd/cmdlinepart.c
@@ -47,344 +47,79 @@
* 1 NOR Flash with 2 partitions, 1 NAND with one
* edb7312-nor:256k(ARMboot)ro,-(root);edb7312-nand:-(home)
*/
+ /*
+ * Copyright  2013 Cai Zhiyong <caizhiyong@xxxxxxxxxx>
+ * Rewrite the cmdline parser code, adjust it to a library-style code.
+ * this module only use the cmdline parser lib.
+ */

#include <linux/kernel.h>
-#include <linux/slab.h>
#include <linux/mtd/mtd.h>
#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);
- }
- }
-
- /* fetch partition name and flags */
- mask_flags = 0; /* this is going to be a regular partition */
- delim = 0;
-
- /* check for offset */
- if (*s == '@') {
- s++;
- offset = memparse(s, &s);
- }
+ struct mtd_partition *mtdpart = &((struct mtd_partition *)param)[slot];

- /* now look for name */
- if (*s == '(')
- delim = ')';
+ mtdpart->offset = subpart->from;
+ mtdpart->size = subpart->size;
+ mtdpart->name = subpart->name;
+ mtdpart->mask_flags = 0;

- if (delim) {
- char *p;
+ if (subpart->flags & PF_RDONLY)
+ mtdpart->mask_flags |= MTD_WRITEABLE;

- 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_POWERUP_LOCK)
+ mtdpart->mask_flags |= MTD_POWERUP_LOCK;

- /* 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));
-
- /* 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.
- */
-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
- * obtain the partitioning information. At this point the command line
- * arguments will actually be parsed and turned to struct mtd_partition
- * information. It returns partitions for the requested mtd device, or
- * the first one in the chain if a NULL mtd_id is passed in.
- */
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);

- /*
- * 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;
+ if (cmdline_parts_parse(&mtd_cmdline_parts, mtdparts)) {
+ mtdparts = NULL;
+ return -EINVAL;
+ }
+ 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;
+ return cmdline_parts_set(parts, master->size, 0, add_part,
+ (void *)*pparts);
}

-
-/*
- * 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;
-}
-
-__setup("mtdparts=", mtdpart_setup);
-
static struct mtd_part_parser cmdline_parser = {
.owner = THIS_MODULE,
.parse_fn = parse_cmdline_partitions,
@@ -393,8 +128,6 @@ 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);
}

--
1.8.1.5

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