| Message ID | 20211210095955.18094-1-christian.storm@siemens.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [1/4] util: Factor out get_root_containerized_fs() | expand |
On 10.12.21 10:59, Christian Storm wrote: > Signed-off-by: Christian Storm <christian.storm@siemens.com> > --- > core/util.c | 39 +++++++++++++++++++++++++-------------- > 1 file changed, 25 insertions(+), 14 deletions(-) > > diff --git a/core/util.c b/core/util.c > index 3eeec41..b996cd3 100644 > --- a/core/util.c > +++ b/core/util.c > @@ -922,12 +922,32 @@ size_t snescape(char *dst, size_t n, const char *src) > } > > /* > - * This returns the device name where rootfs is mounted > + * If major:minor is a containerized filesystem, e.g., in case of LUKS, > + * return the pointed-to device name. > */ > - > static int filter_slave(const struct dirent *ent) { > return (strcmp(ent->d_name, ".") && strcmp(ent->d_name, "..")); > } > +static char *get_root_containerized_fs(int major, int minor) > +{ > + struct dirent **devlist = NULL; > + char *devname = NULL; > + char buf[23+4+7+1]; > + int ret = snprintf(buf, sizeof(buf), "/sys/dev/block/%d:%d/slaves", major, minor); > + if (ret < 0 || ret >= sizeof(buf)) { > + return NULL; > + } > + if (scandir(buf, &devlist, filter_slave, NULL) == 1) { > + devname = strdup(devlist[0]->d_name); > + } > + free(devlist); > + return devname; > +} > + > +/* > + * Return the rootfs's device name from /proc/partitions supporting > + * containerized filesystems such as, e.g., LUKS. > + */ > static char *get_root_from_partitions(void) > { > struct stat info; > @@ -935,8 +955,7 @@ static char *get_root_from_partitions(void) > char *devname = NULL; > unsigned long major, minor, nblocks; > char buf[256]; > - int ret, dev_major, dev_minor, n; > - struct dirent **devlist = NULL; > + int ret, dev_major, dev_minor; > > if (stat("/", &info) < 0) > return NULL; > @@ -944,18 +963,10 @@ static char *get_root_from_partitions(void) > dev_major = info.st_dev / 256; > dev_minor = info.st_dev % 256; > > - /* > - * Check if this is just a container, for example in case of LUKS > - * Search if the device has slaves pointing to another device > - */ > - snprintf(buf, sizeof(buf) - 1, "/sys/dev/block/%d:%d/slaves", dev_major, dev_minor); > - n = scandir(buf, &devlist, filter_slave, NULL); > - if (n == 1) { > - devname = strdup(devlist[0]->d_name); > - free(devlist); > + devname = get_root_containerized_fs(dev_major, dev_minor); > + if (devname) { > return devname; > } > - free(devlist); > > fp = fopen("/proc/partitions", "r"); > if (!fp) > Acked-by : Stefano Babic <sbabic@denx.de> Best regards, Stefano Babic
diff --git a/core/util.c b/core/util.c index 3eeec41..b996cd3 100644 --- a/core/util.c +++ b/core/util.c @@ -922,12 +922,32 @@ size_t snescape(char *dst, size_t n, const char *src) } /* - * This returns the device name where rootfs is mounted + * If major:minor is a containerized filesystem, e.g., in case of LUKS, + * return the pointed-to device name. */ - static int filter_slave(const struct dirent *ent) { return (strcmp(ent->d_name, ".") && strcmp(ent->d_name, "..")); } +static char *get_root_containerized_fs(int major, int minor) +{ + struct dirent **devlist = NULL; + char *devname = NULL; + char buf[23+4+7+1]; + int ret = snprintf(buf, sizeof(buf), "/sys/dev/block/%d:%d/slaves", major, minor); + if (ret < 0 || ret >= sizeof(buf)) { + return NULL; + } + if (scandir(buf, &devlist, filter_slave, NULL) == 1) { + devname = strdup(devlist[0]->d_name); + } + free(devlist); + return devname; +} + +/* + * Return the rootfs's device name from /proc/partitions supporting + * containerized filesystems such as, e.g., LUKS. + */ static char *get_root_from_partitions(void) { struct stat info; @@ -935,8 +955,7 @@ static char *get_root_from_partitions(void) char *devname = NULL; unsigned long major, minor, nblocks; char buf[256]; - int ret, dev_major, dev_minor, n; - struct dirent **devlist = NULL; + int ret, dev_major, dev_minor; if (stat("/", &info) < 0) return NULL; @@ -944,18 +963,10 @@ static char *get_root_from_partitions(void) dev_major = info.st_dev / 256; dev_minor = info.st_dev % 256; - /* - * Check if this is just a container, for example in case of LUKS - * Search if the device has slaves pointing to another device - */ - snprintf(buf, sizeof(buf) - 1, "/sys/dev/block/%d:%d/slaves", dev_major, dev_minor); - n = scandir(buf, &devlist, filter_slave, NULL); - if (n == 1) { - devname = strdup(devlist[0]->d_name); - free(devlist); + devname = get_root_containerized_fs(dev_major, dev_minor); + if (devname) { return devname; } - free(devlist); fp = fopen("/proc/partitions", "r"); if (!fp)
Signed-off-by: Christian Storm <christian.storm@siemens.com> --- core/util.c | 39 +++++++++++++++++++++++++-------------- 1 file changed, 25 insertions(+), 14 deletions(-)