diff options
| -rw-r--r-- | Documentation/block/cmdline-partition.txt | 39 | ||||
| -rw-r--r-- | block/Kconfig | 6 | ||||
| -rw-r--r-- | block/Makefile | 1 | ||||
| -rw-r--r-- | block/cmdline-parser.c | 250 | ||||
| -rw-r--r-- | block/partitions/Kconfig | 7 | ||||
| -rw-r--r-- | block/partitions/Makefile | 1 | ||||
| -rw-r--r-- | block/partitions/check.c | 4 | ||||
| -rw-r--r-- | block/partitions/cmdline.c | 99 | ||||
| -rw-r--r-- | block/partitions/cmdline.h | 2 | ||||
| -rw-r--r-- | include/linux/cmdline-parser.h | 43 |
10 files changed, 452 insertions, 0 deletions
diff --git a/Documentation/block/cmdline-partition.txt b/Documentation/block/cmdline-partition.txt new file mode 100644 index 0000000..2bbf4cc --- /dev/null +++ b/Documentation/block/cmdline-partition.txt @@ -0,0 +1,39 @@ +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>] + <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: + '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/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..cc2637f --- /dev/null +++ b/block/cmdline-parser.c @@ -0,0 +1,250 @@ +/* + * 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; + } +} diff --git a/block/partitions/Kconfig b/block/partitions/Kconfig index 4cebb2f..87a3208 100644 --- a/block/partitions/Kconfig +++ b/block/partitions/Kconfig @@ -260,3 +260,10 @@ config SYSV68_PARTITION partition table format used by Motorola Delta machines (using sysv68). Otherwise, say N. + +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/Makefile b/block/partitions/Makefile index 2be4d7b..37a9527 100644 --- a/block/partitions/Makefile +++ b/block/partitions/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_ACORN_PARTITION) += acorn.o obj-$(CONFIG_AMIGA_PARTITION) += amiga.o obj-$(CONFIG_ATARI_PARTITION) += atari.o obj-$(CONFIG_AIX_PARTITION) += aix.o +obj-$(CONFIG_CMDLINE_PARTITION) += cmdline.o obj-$(CONFIG_MAC_PARTITION) += mac.o obj-$(CONFIG_LDM_PARTITION) += ldm.o obj-$(CONFIG_MSDOS_PARTITION) += msdos.o diff --git a/block/partitions/check.c b/block/partitions/check.c index 19ba207..9ac1df7 100644 --- a/block/partitions/check.c +++ b/block/partitions/check.c @@ -34,6 +34,7 @@ #include "efi.h" #include "karma.h" #include "sysv68.h" +#include "cmdline.h" int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/ @@ -65,6 +66,9 @@ static int (*check_part[])(struct parsed_partitions *) = { adfspart_check_ADFS, #endif +#ifdef CONFIG_CMDLINE_PARTITION + cmdline_partition, +#endif #ifdef CONFIG_EFI_PARTITION efi_partition, /* this must come before msdos */ #endif diff --git a/block/partitions/cmdline.c b/block/partitions/cmdline.c new file mode 100644 index 0000000..56cf4ff --- /dev/null +++ b/block/partitions/cmdline.c @@ -0,0 +1,99 @@ +/* + * Copyright (C) 2013 HUAWEI + * Author: Cai Zhiyong <caizhiyong@huawei.com> + * + * 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. + * + * Verbose config please reference "Documentation/block/cmdline-partition.txt" + * + */ + +#include <linux/cmdline-parser.h> + +#include "check.h" +#include "cmdline.h" + +static char *cmdline; +static struct cmdline_parts *bdev_parts; + +static int add_part(int slot, struct cmdline_subpart *subpart, void *param) +{ + int label_min; + struct partition_meta_info *info; + char tmp[sizeof(info->volname) + 4]; + struct parsed_partitions *state = (struct parsed_partitions *)param; + + if (slot >= state->limit) + return 1; + + 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; + + return 0; +} + +static int __init cmdline_parts_setup(char *s) +{ + cmdline = 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) +{ + sector_t disk_size; + char bdev[BDEVNAME_SIZE]; + struct cmdline_parts *parts; + + if (cmdline) { + if (bdev_parts) + cmdline_parts_free(&bdev_parts); + + if (cmdline_parts_parse(&bdev_parts, cmdline)) { + cmdline = NULL; + return -1; + } + cmdline = NULL; + } + + 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; + + cmdline_parts_set(parts, disk_size, 1, add_part, (void *)state); + + strlcat(state->pp_buf, "\n", PAGE_SIZE); + + return 1; +} diff --git a/block/partitions/cmdline.h b/block/partitions/cmdline.h new file mode 100644 index 0000000..26e0f8d --- /dev/null +++ b/block/partitions/cmdline.h @@ -0,0 +1,2 @@ + +int cmdline_partition(struct parsed_partitions *state); 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 <caizhiyong@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 */ |
