diff options
Diffstat (limited to 'extlinux/main.c')
| -rw-r--r-- | extlinux/main.c | 52 |
1 files changed, 46 insertions, 6 deletions
diff --git a/extlinux/main.c b/extlinux/main.c index 05b390f3..c29e3b0b 100644 --- a/extlinux/main.c +++ b/extlinux/main.c @@ -139,6 +139,8 @@ static const char short_options[] = "iUuzS:H:rvho:O"; /* the btrfs partition first 64K blank area is used to store boot sector and boot image, the boot sector is from 0~512, the boot image starts at 2K */ #define BTRFS_EXTLINUX_OFFSET (2*1024) +#define BTRFS_SUBVOL_OPT "subvol=" +static char subvol[64]; /* * Boot block */ @@ -366,7 +368,7 @@ int patch_file_and_bootblock(int fd, const char *dir, int devfd) struct patch_area *patcharea; int i, dw, nptrs; uint32_t csum; - int secptroffset, diroffset, dirlen; + int secptroffset, diroffset, dirlen, subvoloffset, subvollen; char *dirpath, *subpath; dirpath = realpath(dir, NULL); @@ -487,6 +489,16 @@ int patch_file_and_bootblock(int fd, const char *dir, int devfd) } strncpy((char *)boot_image + diroffset, subpath, dirlen); free(dirpath); + /* write subvol info if we have */ + if (*subvol) { + subvoloffset = get_16(&patcharea->subvoloffset); + subvollen = get_16(&patcharea->subvollen); + if (subvollen <= strlen(subvol)) { + fprintf(stderr, "Subvol name too long... aborting install!\n"); + exit(1); + } + strncpy((char *)boot_image + subvoloffset, subvol, subvollen); + } /* Now produce a checksum */ set_32(&patcharea->checksum, 0); @@ -888,8 +900,22 @@ static const char *find_device(const char *mtab_file, dev_t dev) case BTRFS: if (!strcmp(mnt->mnt_type, "btrfs") && !stat(mnt->mnt_dir, &dst) && - dst.st_dev == dev) - done = true; + dst.st_dev == dev) { + char *opt = strstr(mnt->mnt_opts, BTRFS_SUBVOL_OPT); + + if (opt) { + if (!subvol[0]) { + char *tmp; + + strcpy(subvol, opt + sizeof(BTRFS_SUBVOL_OPT) - 1); + tmp = strchr(subvol, 32); + if (tmp) + *tmp = '\0'; + } + break; /* should break and let upper layer try again */ + } else + done = true; + } break; case EXT2: if ((!strcmp(mnt->mnt_type, "ext2") || @@ -943,10 +969,24 @@ static const char *get_devname(const char *path) #else - devname = find_device("/proc/mounts", st.st_dev); + /* check /etc/mtab first, since btrfs subvol info is only in here */ + devname = find_device("/etc/mtab", st.st_dev); + if (subvol[0] && !devname) { /* we just find it is a btrfs subvol */ + char parent[256]; + char *tmp; + + strcpy(parent, path); + tmp = strrchr(parent, '/'); + if (tmp) { + *tmp = '\0'; + fprintf(stderr, "%s is subvol, try its parent dir %s\n", path, parent); + devname = get_devname(parent); + } else + devname = NULL; + } if (!devname) { - /* Didn't find it in /proc/mounts, try /etc/mtab */ - devname = find_device("/etc/mtab", st.st_dev); + /* Didn't find it in /etc/mtab, try /proc/mounts */ + devname = find_device("/proc/mounts", st.st_dev); } if (!devname) { fprintf(stderr, "%s: cannot find device for path %s\n", program, path); |