diff options
| -rw-r--r-- | src/basic/util.c | 131 | ||||
| -rw-r--r-- | src/basic/util.h | 3 | ||||
| -rw-r--r-- | src/gpt-auto-generator/gpt-auto-generator.c | 130 |
3 files changed, 134 insertions, 130 deletions
diff --git a/src/basic/util.c b/src/basic/util.c index 2f45128ed4..daaee99284 100644 --- a/src/basic/util.c +++ b/src/basic/util.c @@ -34,6 +34,7 @@ #include <unistd.h> #include "alloc-util.h" +#include "btrfs-util.h" #include "build.h" #include "cgroup-util.h" #include "def.h" @@ -719,3 +720,133 @@ int version(void) { SYSTEMD_FEATURES); return 0; } + +int get_block_device(const char *path, dev_t *dev) { + struct stat st; + struct statfs sfs; + + assert(path); + assert(dev); + + /* Get's the block device directly backing a file system. If + * the block device is encrypted, returns the device mapper + * block device. */ + + if (lstat(path, &st)) + return -errno; + + if (major(st.st_dev) != 0) { + *dev = st.st_dev; + return 1; + } + + if (statfs(path, &sfs) < 0) + return -errno; + + if (F_TYPE_EQUAL(sfs.f_type, BTRFS_SUPER_MAGIC)) + return btrfs_get_block_device(path, dev); + + return 0; +} + +int get_block_device_harder(const char *path, dev_t *dev) { + _cleanup_closedir_ DIR *d = NULL; + _cleanup_free_ char *p = NULL, *t = NULL; + struct dirent *de, *found = NULL; + const char *q; + unsigned maj, min; + dev_t dt; + int r; + + assert(path); + assert(dev); + + /* Gets the backing block device for a file system, and + * handles LUKS encrypted file systems, looking for its + * immediate parent, if there is one. */ + + r = get_block_device(path, &dt); + if (r <= 0) + return r; + + if (asprintf(&p, "/sys/dev/block/%u:%u/slaves", major(dt), minor(dt)) < 0) + return -ENOMEM; + + d = opendir(p); + if (!d) { + if (errno == ENOENT) + goto fallback; + + return -errno; + } + + FOREACH_DIRENT_ALL(de, d, return -errno) { + + if (dot_or_dot_dot(de->d_name)) + continue; + + if (!IN_SET(de->d_type, DT_LNK, DT_UNKNOWN)) + continue; + + if (found) { + _cleanup_free_ char *u = NULL, *v = NULL, *a = NULL, *b = NULL; + + /* We found a device backed by multiple other devices. We don't really support automatic + * discovery on such setups, with the exception of dm-verity partitions. In this case there are + * two backing devices: the data partition and the hash partition. We are fine with such + * setups, however, only if both partitions are on the same physical device. Hence, let's + * verify this. */ + + u = strjoin(p, "/", de->d_name, "/../dev"); + if (!u) + return -ENOMEM; + + v = strjoin(p, "/", found->d_name, "/../dev"); + if (!v) + return -ENOMEM; + + r = read_one_line_file(u, &a); + if (r < 0) { + log_debug_errno(r, "Failed to read %s: %m", u); + goto fallback; + } + + r = read_one_line_file(v, &b); + if (r < 0) { + log_debug_errno(r, "Failed to read %s: %m", v); + goto fallback; + } + + /* Check if the parent device is the same. If not, then the two backing devices are on + * different physical devices, and we don't support that. */ + if (!streq(a, b)) + goto fallback; + } + + found = de; + } + + if (!found) + goto fallback; + + q = strjoina(p, "/", found->d_name, "/dev"); + + r = read_one_line_file(q, &t); + if (r == -ENOENT) + goto fallback; + if (r < 0) + return r; + + if (sscanf(t, "%u:%u", &maj, &min) != 2) + return -EINVAL; + + if (maj == 0) + goto fallback; + + *dev = makedev(maj, min); + return 1; + +fallback: + *dev = dt; + return 1; +} diff --git a/src/basic/util.h b/src/basic/util.h index c7da6c39bf..b31dfd1c92 100644 --- a/src/basic/util.h +++ b/src/basic/util.h @@ -192,3 +192,6 @@ uint64_t system_tasks_max_scale(uint64_t v, uint64_t max); int update_reboot_parameter_and_warn(const char *param); int version(void); + +int get_block_device(const char *path, dev_t *dev); +int get_block_device_harder(const char *path, dev_t *dev); diff --git a/src/gpt-auto-generator/gpt-auto-generator.c b/src/gpt-auto-generator/gpt-auto-generator.c index a6c0b33fbb..dcbf3ff061 100644 --- a/src/gpt-auto-generator/gpt-auto-generator.c +++ b/src/gpt-auto-generator/gpt-auto-generator.c @@ -571,136 +571,6 @@ static int enumerate_partitions(dev_t devnum) { return r; } -static int get_block_device(const char *path, dev_t *dev) { - struct stat st; - struct statfs sfs; - - assert(path); - assert(dev); - - /* Get's the block device directly backing a file system. If - * the block device is encrypted, returns the device mapper - * block device. */ - - if (lstat(path, &st)) - return -errno; - - if (major(st.st_dev) != 0) { - *dev = st.st_dev; - return 1; - } - - if (statfs(path, &sfs) < 0) - return -errno; - - if (F_TYPE_EQUAL(sfs.f_type, BTRFS_SUPER_MAGIC)) - return btrfs_get_block_device(path, dev); - - return 0; -} - -static int get_block_device_harder(const char *path, dev_t *dev) { - _cleanup_closedir_ DIR *d = NULL; - _cleanup_free_ char *p = NULL, *t = NULL; - struct dirent *de, *found = NULL; - const char *q; - unsigned maj, min; - dev_t dt; - int r; - - assert(path); - assert(dev); - - /* Gets the backing block device for a file system, and - * handles LUKS encrypted file systems, looking for its - * immediate parent, if there is one. */ - - r = get_block_device(path, &dt); - if (r <= 0) - return r; - - if (asprintf(&p, "/sys/dev/block/%u:%u/slaves", major(dt), minor(dt)) < 0) - return -ENOMEM; - - d = opendir(p); - if (!d) { - if (errno == ENOENT) - goto fallback; - - return -errno; - } - - FOREACH_DIRENT_ALL(de, d, return -errno) { - - if (dot_or_dot_dot(de->d_name)) - continue; - - if (!IN_SET(de->d_type, DT_LNK, DT_UNKNOWN)) - continue; - - if (found) { - _cleanup_free_ char *u = NULL, *v = NULL, *a = NULL, *b = NULL; - - /* We found a device backed by multiple other devices. We don't really support automatic - * discovery on such setups, with the exception of dm-verity partitions. In this case there are - * two backing devices: the data partition and the hash partition. We are fine with such - * setups, however, only if both partitions are on the same physical device. Hence, let's - * verify this. */ - - u = strjoin(p, "/", de->d_name, "/../dev"); - if (!u) - return -ENOMEM; - - v = strjoin(p, "/", found->d_name, "/../dev"); - if (!v) - return -ENOMEM; - - r = read_one_line_file(u, &a); - if (r < 0) { - log_debug_errno(r, "Failed to read %s: %m", u); - goto fallback; - } - - r = read_one_line_file(v, &b); - if (r < 0) { - log_debug_errno(r, "Failed to read %s: %m", v); - goto fallback; - } - - /* Check if the parent device is the same. If not, then the two backing devices are on - * different physical devices, and we don't support that. */ - if (!streq(a, b)) - goto fallback; - } - - found = de; - } - - if (!found) - goto fallback; - - q = strjoina(p, "/", found->d_name, "/dev"); - - r = read_one_line_file(q, &t); - if (r == -ENOENT) - goto fallback; - if (r < 0) - return r; - - if (sscanf(t, "%u:%u", &maj, &min) != 2) - return -EINVAL; - - if (maj == 0) - goto fallback; - - *dev = makedev(maj, min); - return 1; - -fallback: - *dev = dt; - return 1; -} - static int parse_proc_cmdline_item(const char *key, const char *value, void *data) { int r; |