Add --nid and --path options to fsck.erofs to allow users to check or extract specific sub-directories or files instead of the entire filesystem.
This is useful for targeted data recovery or verifying specific image components without the overhead of a full traversal. Signed-off-by: Inseob Kim <[email protected]> --- v3: update the man page v2: retrieve pnid correctly rather than pnid == nid hack --- fsck/main.c | 82 ++++++++++++++++++++++++++++++++++++++++++------ man/fsck.erofs.1 | 8 +++++ 2 files changed, 81 insertions(+), 9 deletions(-) diff --git a/fsck/main.c b/fsck/main.c index ab697be..16cc627 100644 --- a/fsck/main.c +++ b/fsck/main.c @@ -39,6 +39,8 @@ struct erofsfsck_cfg { bool preserve_owner; bool preserve_perms; bool dump_xattrs; + erofs_nid_t nid; + const char *inode_path; bool nosbcrc; }; static struct erofsfsck_cfg fsckcfg; @@ -59,6 +61,8 @@ static struct option long_options[] = { {"offset", required_argument, 0, 12}, {"xattrs", no_argument, 0, 13}, {"no-xattrs", no_argument, 0, 14}, + {"nid", required_argument, 0, 15}, + {"path", required_argument, 0, 16}, {"no-sbcrc", no_argument, 0, 512}, {0, 0, 0, 0}, }; @@ -110,6 +114,8 @@ static void usage(int argc, char **argv) " --extract[=X] check if all files are well encoded, optionally\n" " extract to X\n" " --offset=# skip # bytes at the beginning of IMAGE\n" + " --nid=# check or extract from the target inode of nid #\n" + " --path=X check or extract from the target inode of path X\n" " --no-sbcrc bypass the superblock checksum verification\n" " --[no-]xattrs whether to dump extended attributes (default off)\n" "\n" @@ -245,6 +251,12 @@ static int erofsfsck_parse_options_cfg(int argc, char **argv) case 14: fsckcfg.dump_xattrs = false; break; + case 15: + fsckcfg.nid = (erofs_nid_t)atoll(optarg); + break; + case 16: + fsckcfg.inode_path = optarg; + break; case 512: fsckcfg.nosbcrc = true; break; @@ -862,6 +874,22 @@ again: return ret; } +struct erofsfsck_get_parent_ctx { + struct erofs_dir_context ctx; + erofs_nid_t pnid; +}; + +static int erofsfsck_get_parent_cb(struct erofs_dir_context *ctx) +{ + struct erofsfsck_get_parent_ctx *pctx = (void *)ctx; + + if (ctx->dot_dotdot && ctx->de_namelen == 2) { + pctx->pnid = ctx->de_nid; + return 1; + } + return 0; +} + static int erofsfsck_dirent_iter(struct erofs_dir_context *ctx) { int ret; @@ -1033,6 +1061,8 @@ int main(int argc, char *argv[]) fsckcfg.preserve_owner = fsckcfg.superuser; fsckcfg.preserve_perms = fsckcfg.superuser; fsckcfg.dump_xattrs = false; + fsckcfg.nid = 0; + fsckcfg.inode_path = NULL; err = erofsfsck_parse_options_cfg(argc, argv); if (err) { @@ -1068,22 +1098,56 @@ int main(int argc, char *argv[]) if (fsckcfg.extract_path) erofsfsck_hardlink_init(); - if (erofs_sb_has_fragments(&g_sbi) && g_sbi.packed_nid > 0) { - err = erofs_packedfile_init(&g_sbi, false); + if (fsckcfg.inode_path) { + struct erofs_inode inode = { .sbi = &g_sbi }; + + err = erofs_ilookup(fsckcfg.inode_path, &inode); if (err) { - erofs_err("failed to initialize packedfile: %s", - erofs_strerror(err)); + erofs_err("failed to lookup %s", fsckcfg.inode_path); goto exit_hardlink; } + fsckcfg.nid = inode.nid; + } else if (!fsckcfg.nid) { + fsckcfg.nid = g_sbi.root_nid; + } - err = erofsfsck_check_inode(g_sbi.packed_nid, g_sbi.packed_nid); - if (err) { - erofs_err("failed to verify packed file"); - goto exit_packedinode; + if (!fsckcfg.inode_path && fsckcfg.nid == g_sbi.root_nid) { + if (erofs_sb_has_fragments(&g_sbi) && g_sbi.packed_nid > 0) { + err = erofs_packedfile_init(&g_sbi, false); + if (err) { + erofs_err("failed to initialize packedfile: %s", + erofs_strerror(err)); + goto exit_hardlink; + } + + err = erofsfsck_check_inode(g_sbi.packed_nid, g_sbi.packed_nid); + if (err) { + erofs_err("failed to verify packed file"); + goto exit_packedinode; + } + } + } + + { + erofs_nid_t pnid = fsckcfg.nid; + + if (fsckcfg.nid != g_sbi.root_nid) { + struct erofs_inode inode = { .sbi = &g_sbi, .nid = fsckcfg.nid }; + + if (!erofs_read_inode_from_disk(&inode) && + S_ISDIR(inode.i_mode)) { + struct erofsfsck_get_parent_ctx ctx = { + .ctx.dir = &inode, + .ctx.cb = erofsfsck_get_parent_cb, + }; + + if (erofs_iterate_dir(&ctx.ctx, false) == 1) + pnid = ctx.pnid; + } } + err = erofsfsck_check_inode(pnid, fsckcfg.nid); } - err = erofsfsck_check_inode(g_sbi.root_nid, g_sbi.root_nid); if (fsckcfg.corrupted) { if (!fsckcfg.extract_path) erofs_err("Found some filesystem corruption"); diff --git a/man/fsck.erofs.1 b/man/fsck.erofs.1 index fb255b4..0f698da 100644 --- a/man/fsck.erofs.1 +++ b/man/fsck.erofs.1 @@ -37,6 +37,14 @@ Optionally extract contents of the \fIIMAGE\fR to \fIdirectory\fR. .B "--no-sbcrc" Bypass the on-disk superblock checksum verification. .TP +.BI "\-\-nid=" # +Specify the target inode by its NID for checking or extraction. +The default is the root inode. +.TP +.BI "\-\-path=" path +Specify the target inode by its path for checking or extraction. If both +\fB\-\-nid\fR and \fB\-\-path\fR are specified, \fB\-\-path\fR takes precedence. +.TP .BI "--[no-]xattrs" Whether to dump extended attributes during extraction (default off). .TP -- 2.53.0.414.gf7e9f6c205-goog
