From e80b0bc976b39e4a9a0b3dd5ebd40a66d183a92f Mon Sep 17 00:00:00 2001 From: John Crispin Date: Wed, 19 Jun 2013 21:14:57 +0200 Subject: [PATCH] add a block-mount replacement Signed-off-by: John Crispin --- block.c | 679 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 679 insertions(+) create mode 100644 block.c diff --git a/block.c b/block.c new file mode 100644 index 0000000..1a303e6 --- /dev/null +++ b/block.c @@ -0,0 +1,679 @@ +/* + * Copyright (C) 2013 Felix Fietkau + * Copyright (C) 2013 John Crispin + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License version 2.1 + * as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include +#include + +#include +#include +#include +#include + +#include "libblkid-tiny/libblkid-tiny.h" + +enum { + TYPE_MOUNT, + TYPE_SWAP, +}; + +struct mount { + struct vlist_node node; + int type; + + char *target; + char *path; + char *options; + char *uuid; + char *label; + int disabled_fsck; + unsigned int prio; +}; + +static struct vlist_tree mounts; +static struct blob_buf b; +static LIST_HEAD(devices); + +enum { + MOUNT_UUID, + MOUNT_LABEL, + MOUNT_ENABLE, + MOUNT_TARGET, + MOUNT_OPTIONS, + __MOUNT_MAX +}; + +static const struct blobmsg_policy mount_policy[__MOUNT_MAX] = { + [MOUNT_UUID] = { .name = "uuid", .type = BLOBMSG_TYPE_STRING }, + [MOUNT_LABEL] = { .name = "label", .type = BLOBMSG_TYPE_STRING }, + [MOUNT_TARGET] = { .name = "target", .type = BLOBMSG_TYPE_STRING }, + [MOUNT_OPTIONS] = { .name = "options", .type = BLOBMSG_TYPE_STRING }, + [MOUNT_ENABLE] = { .name = "enabled", .type = BLOBMSG_TYPE_INT32 }, +}; + +static const struct uci_blob_param_list mount_attr_list = { + .n_params = __MOUNT_MAX, + .params = mount_policy, +}; + +enum { + SWAP_ENABLE, + SWAP_UUID, + SWAP_PRIO, + __SWAP_MAX +}; + +static const struct blobmsg_policy swap_policy[__SWAP_MAX] = { + [SWAP_ENABLE] = { .name = "enabled", .type = BLOBMSG_TYPE_INT32 }, + [SWAP_UUID] = { .name = "uuid", .type = BLOBMSG_TYPE_STRING }, + [SWAP_PRIO] = { .name = "priority", .type = BLOBMSG_TYPE_INT32 }, +}; + +static const struct uci_blob_param_list swap_attr_list = { + .n_params = __SWAP_MAX, + .params = swap_policy, +}; + +static char *blobmsg_get_strdup(struct blob_attr *attr) +{ + if (!attr) + return NULL; + + return strdup(blobmsg_get_string(attr)); +} + +static int mount_add(struct uci_section *s) +{ + struct blob_attr *tb[__MOUNT_MAX] = { 0 }; + struct mount *m; + + blob_buf_init(&b, 0); + uci_to_blob(&b, s, &mount_attr_list); + blobmsg_parse(mount_policy, __MOUNT_MAX, tb, blob_data(b.head), blob_len(b.head)); + + if (!tb[MOUNT_LABEL] && !tb[MOUNT_UUID]) + return -1; + + if (!tb[MOUNT_TARGET]) + return -1; + + m = malloc(sizeof(struct mount)); + m->type = TYPE_MOUNT; + m->uuid = blobmsg_get_strdup(tb[MOUNT_UUID]); + m->label = blobmsg_get_strdup(tb[MOUNT_LABEL]); + m->target = blobmsg_get_strdup(tb[MOUNT_TARGET]); + m->options = blobmsg_get_strdup(tb[MOUNT_OPTIONS]); + + if ((!tb[MOUNT_ENABLE]) || blobmsg_get_u32(tb[MOUNT_ENABLE])) + vlist_add(&mounts, &m->node, m->target); + + return 0; +} + +static int swap_add(struct uci_section *s) +{ + struct blob_attr *tb[__SWAP_MAX] = { 0 }; + struct mount *m; + + blob_buf_init(&b, 0); + uci_to_blob(&b, s, &swap_attr_list); + blobmsg_parse(swap_policy, __SWAP_MAX, tb, blob_data(b.head), blob_len(b.head)); + + if (!tb[SWAP_UUID]) + return -1; + + m = malloc(sizeof(struct mount)); + memset(m, 0, sizeof(struct mount)); + m->type = TYPE_SWAP; + m->uuid = blobmsg_get_strdup(tb[SWAP_UUID]); + if (tb[SWAP_PRIO]) + m->prio = blobmsg_get_u32(tb[SWAP_PRIO]); + if (m->prio) + m->prio = ((m->prio << SWAP_FLAG_PRIO_SHIFT) & SWAP_FLAG_PRIO_MASK) | SWAP_FLAG_PREFER; + + if ((!tb[SWAP_ENABLE]) || blobmsg_get_u32(tb[SWAP_ENABLE])) + vlist_add(&mounts, &m->node, m->uuid); + + return 0; +} + +static struct mount* find_swap(const char *uuid) +{ + struct mount *m; + + if (!uuid) + return NULL; + + vlist_for_each_element(&mounts, m, node) + if ((m->type == TYPE_SWAP) && m->uuid && !strcmp(m->uuid, uuid)) + return m; + + return NULL; +} + +static struct mount* find_block(const char *uuid, const char *label, const char *target) +{ + struct mount *m; + + vlist_for_each_element(&mounts, m, node) { + if ((m->type == TYPE_MOUNT) && m->uuid && uuid && !strcmp(m->uuid, uuid)) + return m; + if ((m->type == TYPE_MOUNT) && m->label && label && !strcmp(m->label, label)) + return m; + if ((m->type == TYPE_MOUNT) && target && !strcmp(m->target, target)) + return m; + } + + return NULL; +} + +static void mounts_update(struct vlist_tree *tree, struct vlist_node *node_new, + struct vlist_node *node_old) +{ +} + +static int config_load(char *cfg) +{ + struct uci_context *ctx; + struct uci_package *pkg; + struct uci_element *e; + + vlist_init(&mounts, avl_strcmp, mounts_update); + + ctx = uci_alloc_context(); + if (cfg) { + char path[32]; + snprintf(path, 32, "%s/etc/config", cfg); + uci_set_confdir(ctx, path); + } + + if (uci_load(ctx, "fstab", &pkg)) + return -1; + + vlist_update(&mounts); + uci_foreach_element(&pkg->sections, e) { + struct uci_section *s = uci_to_section(e); + + if (!strcmp(s->type, "mount")) + mount_add(s); + if (!strcmp(s->type, "swap")) + swap_add(s); + } + vlist_flush(&mounts); + + return 0; +} + +static int _cache_load(const char *path) +{ + int gl_flags = GLOB_NOESCAPE | GLOB_MARK; + int j; + glob_t gl; + + if (glob(path, gl_flags, NULL, &gl) < 0) + return -1; + + for (j = 0; j < gl.gl_pathc; j++) { + struct blkid_struct_probe *pr = malloc(sizeof(struct blkid_struct_probe)); + memset(pr, 0, sizeof(struct blkid_struct_probe)); + probe_block(gl.gl_pathv[j], pr); + if (pr->err) + free(pr); + else + list_add_tail(&pr->list, &devices); + } + + globfree(&gl); + + return 0; +} + +static void cache_load(int mtd) +{ + if (mtd) + _cache_load("/dev/mtdblock*"); + _cache_load("/dev/sd*"); +} + +static int print_block_info(struct blkid_struct_probe *pr) +{ + printf("%s:", pr->dev); + if (pr->uuid[0]) + printf(" UUID=\"%s\"", pr->uuid); + + if (pr->label[0]) + printf(" LABEL=\"%s\"", pr->label); + + if (pr->name[0]) + printf(" NAME=\"%s\"", pr->name); + + if (pr->version[0]) + printf(" VERSION=\"%s\"", pr->version); + + printf(" TYPE=\"%s\"\n", pr->id->name); + + return 0; +} + +static int print_block_uci(struct blkid_struct_probe *pr) +{ + if (!pr->uuid[0]) + return 0; + + if (!strcmp(pr->id->name, "swap")) { + printf("config 'swap'\n"); + } else { + printf("config 'mount'\n"); + printf("\toption\ttarget\t'/mnt/%s'\n", basename(pr->dev)); + } + printf("\toption\tuuid\t'%s'\n", pr->uuid); + printf("\toption\tenabled\t'0'\n\n"); + + return 0; +} + +static struct blkid_struct_probe* find_block_info(char *uuid, char *label, char *path) +{ + struct blkid_struct_probe *pr = NULL; + + if (uuid) + list_for_each_entry(pr, &devices, list) + if (!strcmp(pr->uuid, uuid)) + return pr; + + if (label) + list_for_each_entry(pr, &devices, list) + if (strcmp(pr->label, label)) + return pr; + + if (path) + list_for_each_entry(pr, &devices, list) + if (!strcmp(pr->dev, path)) + return pr; + + return NULL; +} + +static char* find_mount_point(char *block) +{ + FILE *fp = fopen("/proc/mounts", "r"); + static char line[256]; + int len = strlen(block); + char *point = NULL; + + if(!fp) + return NULL; + + while (fgets(line, sizeof(line), fp)) { + if (!strncmp(line, block, len)) { + char *p = &line[len + 1]; + char *t = strstr(p, " "); + + if (!t) + return NULL; + *t = '\0'; + point = p; + break; + } + } + + fclose(fp); + + return point; +} + +static void mkdir_p(char *dir) +{ + char *l = strrchr(dir, '/'); + + if (l) { + *l = '\0'; + mkdir_p(dir); + *l = '/'; + mkdir(dir, 0755); + } +} + +static int main_hotplug(int argc, char **argv) +{ + struct mount *m; + char path[256]; + char *action, *device, *mount_point; + struct blkid_struct_probe *pr; + + action = getenv("ACTION"); + device = getenv("DEVNAME"); + + if (!action || !device) + return -1; + snprintf(path, sizeof(path), "/dev/%s", device); + + if (!strcmp(action, "remove")) { + int err = 0; + mount_point = find_mount_point(path); + if (mount_point) + err = umount2(mount_point, MNT_DETACH); + + if (err) + fprintf(stderr, "unmount of %s failed (%d) - %s\n", + mount_point, err, strerror(err)); + + return 0; + } else if (strcmp(action, "add")) { + fprintf(stderr, "Unkown action %s\n", action); + + return -1; + } + + if (config_load(NULL)) + return -1; + cache_load(0); + + pr = find_block_info(NULL, NULL, path); + if (!pr && pr->uuid) { + fprintf(stderr, "failed to read blockinfo for %s\n", path); + return -1; + } + + m = find_swap(pr->uuid); + if (m) { + if (!strcmp(action, "add")) + swapon(path, m->prio); + else + swapoff(path); + } else { + m = find_block(pr->uuid, pr->label, NULL); + if (m && strcmp(m->target, "/")) { + int err = 0; + + mkdir_p(m->target); + err = mount(path, m->target, pr->id->name, 0, (m->options) ? (m->options) : ("")); + if (err) + fprintf(stderr, "mounting %s (%s) as %s failed (%d) - %s\n", + path, pr->id->name, m->target, err, strerror(err)); + } + } + + return 0; +} + +static int find_block_mtd(char *name, char *part, int plen) +{ + FILE *fp = fopen("/proc/mtd", "r"); + static char line[256]; + char *index = NULL; + + if(!fp) + return -1; + + while (!index && fgets(line, sizeof(line), fp)) { + if (strstr(line, name)) { + char *eol = strstr(line, ":"); + + if (!eol) + continue; + + *eol = '\0'; + index = &line[3]; + } + } + + fclose(fp); + + if (!index) + return -1; + + snprintf(part, plen, "/dev/mtdblock%s", index); + + return 0; +} + +static int mount_extroot(char *path, char *cfg) +{ + struct blkid_struct_probe *pr; + struct mount *m; + int err = -1; + + if (config_load(cfg)) + return 2; + + m = find_block(NULL, NULL, "/"); + if (!m) + return 1; + + pr = find_block_info(m->uuid, m->label, NULL); + if (pr) { + mkdir_p(path); + err = mount(pr->dev, path, pr->id->name, 0, (m->options) ? (m->options) : ("")); + + if (err) + fprintf(stderr, "mounting %s (%s) as %s failed (%d) - %s\n", + pr->dev, pr->id->name, path, err, strerror(err)); + } + + return err; +} + +static int main_extroot(int argc, char **argv) +{ + struct blkid_struct_probe *pr; + char fs[32] = { 0 }; + char fs_data[32] = { 0 }; + int err = 1; + char extroot[] = "/tmp/overlay"; + + if (!getenv("PREINIT")) + return -1; + + if (argc != 2) { + fprintf(stderr, "Usage: block extroot mountpoint\n"); + return 1; + } + + mkblkdev(); + cache_load(1); + + find_block_mtd("rootfs", fs, sizeof(fs)); + if (!fs[0]) + return 2; + + pr = find_block_info(NULL, NULL, fs); + if (!pr || strcmp(pr->id->name, "squashfs")) + return 3; + + find_block_mtd("rootfs_data", fs_data, sizeof(fs_data)); + if (fs_data[0]) { + pr = find_block_info(NULL, NULL, fs_data); + if (pr && !strcmp(pr->id->name, "jffs2")) { + char cfg[] = "/tmp/jffs_cfg"; + + mkdir_p(cfg); + if (!mount(fs_data, cfg, "jffs2", MS_NOATIME, NULL)) { + err = mount_extroot(extroot, cfg); + umount2(cfg, MNT_DETACH); + } + if (err) + rmdir(extroot); + rmdir(cfg); + return err; + } + } + + err = mount_extroot(extroot, NULL); + + return err; +} + +static int main_detect(int argc, char **argv) +{ + struct blkid_struct_probe *pr; + + cache_load(0); + list_for_each_entry(pr, &devices, list) + print_block_uci(pr); + + return 0; +} + +static int main_info(int argc, char **argv) +{ + int i; + struct blkid_struct_probe *pr; + + cache_load(1); + if (argc == 2) { + list_for_each_entry(pr, &devices, list) + print_block_info(pr); + + return 0; + }; + + for (i = 2; i < argc; i++) { + struct stat s; + + if (stat(argv[i], &s)) { + fprintf(stderr, "failed to stat %s\n", argv[i]); + continue; + } + if (!S_ISBLK(s.st_mode)) { + fprintf(stderr, "%s is not a block device\n", argv[i]); + continue; + } + pr = find_block_info(NULL, NULL, argv[i]); + if (pr) + print_block_info(pr); + } + + return 0; +} + +static int main_swapon(int argc, char **argv) +{ + if (argc != 2) { + fprintf(stderr, "Usage: swapoff [-a] [DEVICE]\n\nStop swapping on DEVICE\n\n\t-a Stop swapping on all swap devices\n"); + return -1; + } + + if (!strcmp(argv[1], "-a")) { + struct blkid_struct_probe *pr; + + cache_load(0); + list_for_each_entry(pr, &devices, list) { + if (strcmp(pr->id->name, "swap")) + continue; + if (swapon(pr->dev, 0)) + fprintf(stderr, "failed to swapon %s\n", pr->dev); + } + } else { + struct stat s; + int err; + + if (stat(argv[1], &s) || !S_ISBLK(s.st_mode)) { + fprintf(stderr, "%s is not a block device\n", argv[1]); + return -1; + } + err = swapon(argv[1], 0); + if (err) { + fprintf(stderr, "failed to swapon %s (%d)\n", argv[1], err); + return err; + } + } + + return 0; +} + +static int main_swapoff(int argc, char **argv) +{ + if (argc != 2) { + fprintf(stderr, "Usage: swapoff [-a] [DEVICE]\n\nStop swapping on DEVICE\n\n\t-a Stop swapping on all swap devices\n"); + return -1; + } + + if (!strcmp(argv[1], "-a")) { + FILE *fp = fopen("/proc/swaps", "r"); + char line[256]; + + if (!fp) { + fprintf(stderr, "failed to open /proc/swaps\n"); + return -1; + } + fgets(line, sizeof(line), fp); + while (fgets(line, sizeof(line), fp)) { + char *end = strchr(line, ' '); + int err; + + if (!end) + continue; + *end = '\0'; + err = swapoff(line); + if (err) + fprintf(stderr, "failed to swapoff %s (%d)\n", line, err); + } + fclose(fp); + } else { + struct stat s; + int err; + + if (stat(argv[1], &s) || !S_ISBLK(s.st_mode)) { + fprintf(stderr, "%s is not a block device\n", argv[1]); + return -1; + } + err = swapoff(argv[1]); + if (err) { + fprintf(stderr, "fsiled to swapoff %s (%d)\n", argv[1], err); + return err; + } + } + + return 0; +} + +int main(int argc, char **argv) +{ + char *base = basename(*argv); + + if (!strcmp(base, "swapon")) + return main_swapon(argc, argv); + + if (!strcmp(base, "swapoff")) + return main_swapoff(argc, argv); + + if ((argc > 1) && !strcmp(base, "block")) { + if (!strcmp(argv[1], "info")) + return main_info(argc, argv); + + if (!strcmp(argv[1], "detect")) + return main_detect(argc, argv); + + if (!strcmp(argv[1], "hotplug")) + return main_hotplug(argc, argv); + + if (!strcmp(argv[1], "extroot")) + return main_extroot(argc, argv); + } + + fprintf(stderr, "Usage: block \n"); + + return -1; +} -- 2.25.1