From: Cai Zhiyong <caizhiy...@huawei.com> move the command line parser to a separate module, and change it into library-style code.
reference: https://lkml.org/lkml/2013/8/6/550 Signed-off-by: Cai Zhiyong <caizhiy...@huawei.com> --- block/Kconfig | 6 + block/Makefile | 1 + block/cmdline-parser.c | 249 +++++++++++++++++++++++++++++++++ block/partitions/Kconfig | 1 + block/partitions/cmdline.c | 311 ++++++----------------------------------- include/linux/cmdline-parser.h | 43 ++++++ 6 files changed, 342 insertions(+), 269 deletions(-) create mode 100644 block/cmdline-parser.c create mode 100644 include/linux/cmdline-parser.h diff --git a/block/Kconfig b/block/Kconfig index a7e40a7..7f38e40 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -99,6 +99,12 @@ config BLK_DEV_THROTTLING See Documentation/cgroups/blkio-controller.txt for more information. +config CMDLINE_PARSER + bool "Block device command line partition parser" + default n + ---help--- + Parsing command line, get the partitions information. + menu "Partition Types" source "block/partitions/Kconfig" diff --git a/block/Makefile b/block/Makefile index 39b76ba..4fa4be5 100644 --- a/block/Makefile +++ b/block/Makefile @@ -18,3 +18,4 @@ obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o obj-$(CONFIG_BLK_DEV_INTEGRITY) += blk-integrity.o +obj-$(CONFIG_CMDLINE_PARSER) += cmdline-parser.o diff --git a/block/cmdline-parser.c b/block/cmdline-parser.c new file mode 100644 index 0000000..18fb435 --- /dev/null +++ b/block/cmdline-parser.c @@ -0,0 +1,249 @@ +/* + * Parse command line, get partition information + * + * Written by Cai Zhiyong <caizhiy...@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."); + 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; + } +} diff --git a/block/partitions/Kconfig b/block/partitions/Kconfig index 2ebf251..87a3208 100644 --- a/block/partitions/Kconfig +++ b/block/partitions/Kconfig @@ -263,6 +263,7 @@ config SYSV68_PARTITION config CMDLINE_PARTITION bool "Command line partition support" if PARTITION_ADVANCED + select CMDLINE_PARSER help Say Y here if you would read the partitions table from bootargs. The format for the command line is just like mtdparts. diff --git a/block/partitions/cmdline.c b/block/partitions/cmdline.c index 1a1eac7..56cf4ff 100644 --- a/block/partitions/cmdline.c +++ b/block/partitions/cmdline.c @@ -8,219 +8,54 @@ * by absolute address of data on the block device. * Users can easily change the partition. * - * This code reference MTD partition, source "drivers/mtd/cmdlinepart.c" * The format for the command line is just like mtdparts. * * Verbose config please reference "Documentation/block/cmdline-partition.txt" * */ -#include <linux/buffer_head.h> -#include <linux/module.h> -#include <linux/ctype.h> +#include <linux/cmdline-parser.h> #include "check.h" #include "cmdline.h" -struct cmdline_subpart { - char name[BDEVNAME_SIZE]; /* partition name, such as 'rootfs' */ - sector_t from; - sector_t size; - struct cmdline_subpart *next_subpart; -}; +static char *cmdline; +static struct cmdline_parts *bdev_parts; -struct cmdline_parts { - char name[BDEVNAME_SIZE]; /* block device, such as 'mmcblk0' */ - struct cmdline_subpart *subpart; - struct cmdline_parts *next_parts; -}; - -static char *cmdline_string; -static struct cmdline_parts *cmdline_parts; - -static int parse_subpart(struct cmdline_subpart **subpart, char *cmdline) -{ - 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 (*cmdline == '-') { - new_subpart->size = (sector_t)(~0ULL); - cmdline++; - } else { - new_subpart->size = (sector_t)memparse(cmdline, &cmdline); - if (new_subpart->size < (sector_t)PAGE_SIZE) { - pr_warn("cmdline partition size is invalid."); - ret = -EINVAL; - goto fail; - } - } - - if (*cmdline == '@') { - cmdline++; - new_subpart->from = (sector_t)memparse(cmdline, &cmdline); - } else { - new_subpart->from = (sector_t)(~0ULL); - } - - if (*cmdline == '(') { - int length; - char *next = strchr(++cmdline, ')'); - - if (!next) { - pr_warn("cmdline partition format is invalid."); - ret = -EINVAL; - goto fail; - } - - length = min_t(int, next - cmdline, - sizeof(new_subpart->name) - 1); - strncpy(new_subpart->name, cmdline, length); - new_subpart->name[length] = '\0'; - - cmdline = ++next; - } else - new_subpart->name[0] = '\0'; - - *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 void free_parts(struct cmdline_parts **parts) -{ - struct cmdline_parts *next_parts; - - while (*parts) { - next_parts = (*parts)->next_parts; - free_subpart(*parts); - kfree(*parts); - *parts = next_parts; - } -} - -static int parse_parts(struct cmdline_parts **parts, const char *cmdline) +static int add_part(int slot, struct cmdline_subpart *subpart, void *param) { - int ret = -EINVAL; - char *next; - int length; - struct cmdline_subpart **next_subpart; - struct cmdline_parts *newparts; - char buf[BDEVNAME_SIZE + 32 + 4]; + int label_min; + struct partition_meta_info *info; + char tmp[sizeof(info->volname) + 4]; + struct parsed_partitions *state = (struct parsed_partitions *)param; - *parts = NULL; + if (slot >= state->limit) + return 1; - newparts = kzalloc(sizeof(struct cmdline_parts), GFP_KERNEL); - if (!newparts) - return -ENOMEM; + put_partition(state, slot, subpart->from >> 9, + subpart->size >> 9); - next = strchr(cmdline, ':'); - if (!next) { - pr_warn("cmdline partition has no block device."); - goto fail; - } - - length = min_t(int, next - cmdline, sizeof(newparts->name) - 1); - strncpy(newparts->name, cmdline, length); - newparts->name[length] = '\0'; - - next_subpart = &newparts->subpart; + info = &state->parts[slot].info; - while (next && *(++next)) { - cmdline = next; - next = strchr(cmdline, ','); + label_min = min_t(int, sizeof(info->volname) - 1, + sizeof(subpart->name)); + strncpy(info->volname, subpart->name, label_min); + info->volname[label_min] = '\0'; - length = (!next) ? (sizeof(buf) - 1) : - min_t(int, next - cmdline, sizeof(buf) - 1); + snprintf(tmp, sizeof(tmp), "(%s)", info->volname); + strlcat(state->pp_buf, tmp, PAGE_SIZE); - strncpy(buf, cmdline, length); - buf[length] = '\0'; - - ret = parse_subpart(next_subpart, buf); - if (ret) - goto fail; - - next_subpart = &(*next_subpart)->next_subpart; - } - - if (!newparts->subpart) { - pr_warn("cmdline partition has no valid partition."); - goto fail; - } - - *parts = newparts; + state->parts[slot].has_info = true; return 0; -fail: - free_subpart(newparts); - kfree(newparts); - return ret; } -static int parse_cmdline(struct cmdline_parts **parts, const char *cmdline) +static int __init cmdline_parts_setup(char *s) { - 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: - free_parts(parts); - goto done; + cmdline = s; + return 1; } +__setup("blkdevparts=", cmdline_parts_setup); /* * Purpose: allocate cmdline partitions. @@ -229,98 +64,36 @@ fail: * 0 if this isn't our partition table * 1 if successful */ -static int parse_partitions(struct parsed_partitions *state, - struct cmdline_parts *parts) +int cmdline_partition(struct parsed_partitions *state) { - int slot; - sector_t from = 0; sector_t disk_size; - char buf[BDEVNAME_SIZE]; - struct cmdline_subpart *subpart; + char bdev[BDEVNAME_SIZE]; + struct cmdline_parts *parts; + + if (cmdline) { + if (bdev_parts) + cmdline_parts_free(&bdev_parts); - bdevname(state->bdev, buf); + if (cmdline_parts_parse(&bdev_parts, cmdline)) { + cmdline = NULL; + return -1; + } + cmdline = NULL; + } - while (parts && strncmp(buf, parts->name, BDEVNAME_SIZE)) - parts = parts->next_parts; + if (!bdev_parts) + return 0; + bdevname(state->bdev, bdev); + parts = cmdline_parts_find(bdev_parts, bdev); if (!parts) return 0; disk_size = get_capacity(state->bdev->bd_disk) << 9; - for (slot = 1, subpart = parts->subpart; - subpart && slot < state->limit; - subpart = subpart->next_subpart, slot++) { - int label_min; - struct partition_meta_info *info; - char tmp[sizeof(info->volname) + 4]; - - 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; - - put_partition(state, slot, subpart->from >> 9, - subpart->size >> 9); - - info = &state->parts[slot].info; - - label_min = min_t(int, sizeof(info->volname) - 1, - sizeof(subpart->name)); - strncpy(info->volname, subpart->name, label_min); - info->volname[label_min] = '\0'; - - snprintf(tmp, sizeof(tmp), "(%s)", info->volname); - strlcat(state->pp_buf, tmp, PAGE_SIZE); - - state->parts[slot].has_info = true; - } + cmdline_parts_set(parts, disk_size, 1, add_part, (void *)state); strlcat(state->pp_buf, "\n", PAGE_SIZE); return 1; } - -static int __init cmdline_parts_setup(char *s) -{ - cmdline_string = s; - return 1; -} -__setup("blkdevparts=", cmdline_parts_setup); - -/* - * Purpose: allocate cmdline partitions. - * Returns: - * -1 if unable to read the partition table - * 0 if this isn't our partition table - * 1 if successful - */ -int cmdline_partition(struct parsed_partitions *state) -{ - if (cmdline_string) { - if (cmdline_parts) - free_parts(&cmdline_parts); - - if (parse_cmdline(&cmdline_parts, cmdline_string)) - goto fail; - - cmdline_string = NULL; - } - - if (!cmdline_parts) - return 0; - - return parse_partitions(state, cmdline_parts); - -fail: - cmdline_string = NULL; - return -1; -} diff --git a/include/linux/cmdline-parser.h b/include/linux/cmdline-parser.h new file mode 100644 index 0000000..98e892e --- /dev/null +++ b/include/linux/cmdline-parser.h @@ -0,0 +1,43 @@ +/* + * Parsing command line, get the partitions information. + * + * Written by Cai Zhiyong <caizhiy...@huawei.com> + * + */ +#ifndef CMDLINEPARSEH +#define CMDLINEPARSEH + +#include <linux/blkdev.h> + +/* partition flags */ +#define PF_RDONLY 0x01 /* Device is read only */ +#define PF_POWERUP_LOCK 0x02 /* Always locked after reset */ + +struct cmdline_subpart { + char name[BDEVNAME_SIZE]; /* partition name, such as 'rootfs' */ + sector_t from; + sector_t size; + int flags; + struct cmdline_subpart *next_subpart; +}; + +struct cmdline_parts { + char name[BDEVNAME_SIZE]; /* block device, such as 'mmcblk0' */ + unsigned int nr_subparts; + struct cmdline_subpart *subpart; + struct cmdline_parts *next_parts; +}; + +void cmdline_parts_free(struct cmdline_parts **parts); + +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); + +#endif /* CMDLINEPARSEH */ -- 1.8.1.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
