diff options
| -rw-r--r-- | include/linux/genhd.h | 7 | ||||
| -rw-r--r-- | init/do_mounts.c | 183 |
2 files changed, 91 insertions, 99 deletions
diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 22f5b9fd96f8..ca5e356084c3 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -388,18 +388,13 @@ static inline void bd_unlink_disk_holder(struct block_device *bdev, } #endif /* CONFIG_SYSFS */ +dev_t blk_lookup_devt(const char *name, int partno); #ifdef CONFIG_BLOCK void printk_all_partitions(void); -dev_t blk_lookup_devt(const char *name, int partno); #else /* CONFIG_BLOCK */ static inline void printk_all_partitions(void) { } -static inline dev_t blk_lookup_devt(const char *name, int partno) -{ - dev_t devt = MKDEV(0, 0); - return devt; -} #endif /* CONFIG_BLOCK */ #endif /* _LINUX_GENHD_H */ diff --git a/init/do_mounts.c b/init/do_mounts.c index b5f9604d0c98..aef2f24461c7 100644 --- a/init/do_mounts.c +++ b/init/do_mounts.c @@ -90,7 +90,6 @@ no_match: return 0; } - /** * devt_from_partuuid - looks up the dev_t of a partition by its UUID * @uuid_str: char array containing ascii UUID @@ -186,7 +185,83 @@ static int match_dev_by_label(struct device *dev, const void *data) return 0; } -#endif + +static dev_t devt_from_partlabel(const char *label) +{ + struct device *dev; + dev_t devt = 0; + + dev = class_find_device(&block_class, NULL, label, &match_dev_by_label); + if (dev) { + devt = dev->devt; + put_device(dev); + } + + return devt; +} + +static dev_t devt_from_devname(const char *name) +{ + dev_t devt = 0; + int part; + char s[32]; + char *p; + + if (strlen(name) > 31) + return 0; + strcpy(s, name); + for (p = s; *p; p++) { + if (*p == '/') + *p = '!'; + } + + devt = blk_lookup_devt(s, 0); + if (devt) + return devt; + + /* + * Try non-existent, but valid partition, which may only exist after + * opening the device, like partitioned md devices. + */ + while (p > s && isdigit(p[-1])) + p--; + if (p == s || !*p || *p == '0') + return 0; + + /* try disk name without <part number> */ + part = simple_strtoul(p, NULL, 10); + *p = '\0'; + devt = blk_lookup_devt(s, part); + if (devt) + return devt; + + /* try disk name without p<part number> */ + if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p') + return 0; + p[-1] = '\0'; + return blk_lookup_devt(s, part); +} +#endif /* CONFIG_BLOCK */ + +static dev_t devt_from_devnum(const char *name) +{ + unsigned maj, min, offset; + dev_t devt = 0; + char *p, dummy; + + if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 || + sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3) { + devt = MKDEV(maj, min); + if (maj != MAJOR(devt) || min != MINOR(devt)) + return 0; + } else { + devt = new_decode_dev(simple_strtoul(name, &p, 16)); + if (*p) + return 0; + } + + return devt; +} /* * Convert a name into device number. We accept the following variants: @@ -218,101 +293,23 @@ static int match_dev_by_label(struct device *dev, const void *data) * name contains slashes, the device name has them replaced with * bangs. */ - dev_t name_to_dev_t(const char *name) { - char s[32]; - char *p; - dev_t res = 0; - int part; - + if (strcmp(name, "/dev/nfs") == 0) + return Root_NFS; + if (strcmp(name, "/dev/cifs") == 0) + return Root_CIFS; + if (strcmp(name, "/dev/ram") == 0) + return Root_RAM0; #ifdef CONFIG_BLOCK - if (strncmp(name, "PARTUUID=", 9) == 0) { - name += 9; - res = devt_from_partuuid(name); - if (!res) - goto fail; - goto done; - } else if (strncmp(name, "PARTLABEL=", 10) == 0) { - struct device *dev; - - dev = class_find_device(&block_class, NULL, name + 10, - &match_dev_by_label); - if (!dev) - goto fail; - - res = dev->devt; - put_device(dev); - goto done; - } + if (strncmp(name, "PARTUUID=", 9) == 0) + return devt_from_partuuid(name + 9); + if (strncmp(name, "PARTLABEL=", 10) == 0) + return devt_from_partlabel(name + 10); + if (strncmp(name, "/dev/", 5) == 0) + return devt_from_devname(name + 5); #endif - - if (strncmp(name, "/dev/", 5) != 0) { - unsigned maj, min, offset; - char dummy; - - if ((sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2) || - (sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3)) { - res = MKDEV(maj, min); - if (maj != MAJOR(res) || min != MINOR(res)) - goto fail; - } else { - res = new_decode_dev(simple_strtoul(name, &p, 16)); - if (*p) - goto fail; - } - goto done; - } - - name += 5; - res = Root_NFS; - if (strcmp(name, "nfs") == 0) - goto done; - res = Root_CIFS; - if (strcmp(name, "cifs") == 0) - goto done; - res = Root_RAM0; - if (strcmp(name, "ram") == 0) - goto done; - - if (strlen(name) > 31) - goto fail; - strcpy(s, name); - for (p = s; *p; p++) - if (*p == '/') - *p = '!'; - res = blk_lookup_devt(s, 0); - if (res) - goto done; - - /* - * try non-existent, but valid partition, which may only exist - * after revalidating the disk, like partitioned md devices - */ - while (p > s && isdigit(p[-1])) - p--; - if (p == s || !*p || *p == '0') - goto fail; - - /* try disk name without <part number> */ - part = simple_strtoul(p, NULL, 10); - *p = '\0'; - res = blk_lookup_devt(s, part); - if (res) - goto done; - - /* try disk name without p<part number> */ - if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p') - goto fail; - p[-1] = '\0'; - res = blk_lookup_devt(s, part); - if (res) - goto done; - -fail: - return 0; -done: - return res; + return devt_from_devnum(name); } EXPORT_SYMBOL_GPL(name_to_dev_t); |