From: Darrick J. Wong <djwong@xxxxxxxxxx>
Create a command to dump the parents of a file.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
---
db/namei.c | 323 +++++++++++++++++++++++++++++++++++++++++++++++++++++
man/man8/xfs_db.8 | 9 +
2 files changed, 332 insertions(+)
diff --git a/db/namei.c b/db/namei.c
index 41ccaa04b..46b4cacb5 100644
--- a/db/namei.c
+++ b/db/namei.c
@@ -596,6 +596,326 @@ static struct cmdinfo ls_cmd = {
.help = ls_help,
};
+static void
+pptr_emit(
+ struct xfs_inode *ip,
+ unsigned int attr_flags,
+ const uint8_t *name,
+ unsigned int namelen,
+ const void *value,
+ unsigned int valuelen)
+{
+ struct xfs_mount *mp = ip->i_mount;
+ xfs_ino_t parent_ino;
+ uint32_t parent_gen;
+ int error;
+
+ if (!(attr_flags & XFS_ATTR_PARENT))
+ return;
+
+ error = -libxfs_parent_from_attr(mp, attr_flags, name, namelen, value,
+ valuelen, &parent_ino, &parent_gen);
+ if (error)
+ return;
+
+ dbprintf("%18llu:0x%08x %3d %.*s\n", parent_ino, parent_gen, namelen,
+ namelen, name);
+}
+
+static int
+list_sf_pptrs(
+ struct xfs_inode *ip)
+{
+ struct xfs_attr_sf_hdr *hdr = ip->i_af.if_data;
+ struct xfs_attr_sf_entry *sfe;
+ unsigned int i;
+
+ sfe = libxfs_attr_sf_firstentry(hdr);
+ for (i = 0; i < hdr->count; i++) {
+ pptr_emit(ip, sfe->flags, sfe->nameval, sfe->namelen,
+ sfe->nameval + sfe->valuelen, sfe->valuelen);
+
+ sfe = xfs_attr_sf_nextentry(sfe);
+ }
+
+ return 0;
+}
+
+static void
+list_leaf_pptr_entries(
+ struct xfs_inode *ip,
+ struct xfs_buf *bp)
+{
+ struct xfs_attr3_icleaf_hdr ichdr;
+ struct xfs_mount *mp = ip->i_mount;
+ struct xfs_attr_leafblock *leaf = bp->b_addr;
+ struct xfs_attr_leaf_entry *entry;
+ unsigned int i;
+
+ libxfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
+ entry = xfs_attr3_leaf_entryp(leaf);
+
+ for (i = 0; i < ichdr.count; entry++, i++) {
+ struct xfs_attr_leaf_name_local *name_loc;
+
+ /*
+ * Parent pointers cannot be remote values; don't bother
+ * decoding this xattr name.
+ */
+ if (!(entry->flags & XFS_ATTR_LOCAL))
+ continue;
+
+ name_loc = xfs_attr3_leaf_name_local(leaf, i);
+ pptr_emit(ip, entry->flags, name_loc->nameval,
+ name_loc->namelen,
+ name_loc->nameval + name_loc->namelen,
+ be16_to_cpu(name_loc->valuelen));
+ }
+}
+
+static int
+list_leaf_pptrs(
+ struct xfs_inode *ip)
+{
+ struct xfs_buf *leaf_bp;
+ int error;
+
+ error = -libxfs_attr3_leaf_read(NULL, ip, ip->i_ino, 0, &leaf_bp);
+ if (error)
+ return error;
+
+ list_leaf_pptr_entries(ip, leaf_bp);
+ libxfs_trans_brelse(NULL, leaf_bp);
+ return 0;
+}
+
+static int
+find_leftmost_attr_leaf(
+ struct xfs_inode *ip,
+ struct xfs_buf **leaf_bpp)
+{
+ struct xfs_da3_icnode_hdr nodehdr;
+ struct xfs_mount *mp = ip->i_mount;
+ struct xfs_da_intnode *node;
+ struct xfs_da_node_entry *btree;
+ struct xfs_buf *bp;
+ xfs_dablk_t blkno = 0;
+ unsigned int expected_level = 0;
+ int error;
+
+ for (;;) {
+ uint16_t magic;
+
+ error = -libxfs_da3_node_read(NULL, ip, blkno, &bp,
+ XFS_ATTR_FORK);
+ if (error)
+ return error;
+
+ node = bp->b_addr;
+ magic = be16_to_cpu(node->hdr.info.magic);
+ if (magic == XFS_ATTR_LEAF_MAGIC ||
+ magic == XFS_ATTR3_LEAF_MAGIC)
+ break;
+
+ error = EFSCORRUPTED;
+ if (magic != XFS_DA_NODE_MAGIC &&
+ magic != XFS_DA3_NODE_MAGIC)
+ goto out_buf;
+
+ libxfs_da3_node_hdr_from_disk(mp, &nodehdr, node);
+
+ if (nodehdr.count == 0 || nodehdr.level >= XFS_DA_NODE_MAXDEPTH)
+ goto out_buf;
+
+ /* Check the level from the root node. */
+ if (blkno == 0)
+ expected_level = nodehdr.level - 1;
+ else if (expected_level != nodehdr.level)
+ goto out_buf;
+ else
+ expected_level--;
+
+ /* Find the next level towards the leaves of the dabtree. */
+ btree = nodehdr.btree;
+ blkno = be32_to_cpu(btree->before);
+ libxfs_trans_brelse(NULL, bp);
+ }
+
+ error = EFSCORRUPTED;
+ if (expected_level != 0)
+ goto out_buf;
+
+ *leaf_bpp = bp;
+ return 0;
+
+out_buf:
+ libxfs_trans_brelse(NULL, bp);
+ return error;
+}
+
+static int
+list_node_pptrs(
+ struct xfs_inode *ip)
+{
+ struct xfs_attr3_icleaf_hdr leafhdr;
+ struct xfs_mount *mp = ip->i_mount;
+ struct xfs_attr_leafblock *leaf;
+ struct xfs_buf *leaf_bp;
+ int error;
+
+ error = find_leftmost_attr_leaf(ip, &leaf_bp);
+ if (error)
+ return error;
+
+ for (;;) {
+ list_leaf_pptr_entries(ip, leaf_bp);
+
+ /* Find the right sibling of this leaf block. */
+ leaf = leaf_bp->b_addr;
+ libxfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf);
+ if (leafhdr.forw == 0)
+ goto out_leaf;
+
+ libxfs_trans_brelse(NULL, leaf_bp);
+
+ error = -libxfs_attr3_leaf_read(NULL, ip, ip->i_ino,
+ leafhdr.forw, &leaf_bp);
+ if (error)
+ return error;
+ }
+
+out_leaf:
+ libxfs_trans_brelse(NULL, leaf_bp);
+ return error;
+}
+
+static int
+list_pptrs(
+ struct xfs_inode *ip)
+{
+ int error;
+
+ if (!libxfs_inode_hasattr(ip))
+ return 0;
+
+ if (ip->i_af.if_format == XFS_DINODE_FMT_LOCAL)
+ return list_sf_pptrs(ip);
+
+ /* attr functions require that the attr fork is loaded */
+ error = -libxfs_iread_extents(NULL, ip, XFS_ATTR_FORK);
+ if (error)
+ return error;
+
+ if (libxfs_attr_is_leaf(ip))
+ return list_leaf_pptrs(ip);
+
+ return list_node_pptrs(ip);
+}
+
+/* If the io cursor points to a file, list its parents. */
+static int
+parent_cur(
+ char *tag)
+{
+ struct xfs_inode *ip;
+ int error = 0;
+
+ if (!xfs_has_parent(mp))
+ return 0;
+
+ if (iocur_top->typ != &typtab[TYP_INODE])
+ return ENOTDIR;
+
+ error = -libxfs_iget(mp, NULL, iocur_top->ino, 0, &ip);
+ if (error)
+ return error;
+
+ /* List the parents of a file. */
+ if (tag)
+ dbprintf(_("%s:\n"), tag);
+
+ error = list_pptrs(ip);
+ if (error)
+ goto rele;
+
+rele:
+ libxfs_irele(ip);
+ return error;
+}
+
+static void
+parent_help(void)
+{
+ dbprintf(_(
+"\n"
+" List the parents of the currently selected file.\n"
+"\n"
+" Parent pointers will be listed in the format:\n"
+" inode_number:inode_gen ondisk_namehash:namehash name_length name\n"
+ ));
+}
+
+static int
+parent_f(
+ int argc,
+ char **argv)
+{
+ int c;
+ int error = 0;
+
+ while ((c = getopt(argc, argv, "")) != -1) {
+ switch (c) {
+ default:
+ ls_help();
+ return 0;
+ }
+ }
+
+ if (optind == argc) {
+ error = parent_cur(NULL);
+ if (error) {
+ dbprintf("%s\n", strerror(error));
+ exitcode = 1;
+ }
+
+ return 0;
+ }
+
+ for (c = optind; c < argc; c++) {
+ push_cur();
+
+ error = path_walk(argv[c]);
+ if (error)
+ goto err_cur;
+
+ error = parent_cur(argv[c]);
+ if (error)
+ goto err_cur;
+
+ pop_cur();
+ }
+
+ return 0;
+err_cur:
+ pop_cur();
+ if (error) {
+ dbprintf("%s: %s\n", argv[c], strerror(error));
+ exitcode = 1;
+ }
+ return 0;
+}
+
+static struct cmdinfo parent_cmd = {
+ .name = "parent",
+ .altname = "pptr",
+ .cfunc = parent_f,
+ .argmin = 0,
+ .argmax = -1,
+ .canpush = 0,
+ .args = "[paths...]",
+ .help = parent_help,
+};
+
void
namei_init(void)
{
@@ -604,4 +924,7 @@ namei_init(void)
ls_cmd.oneline = _("list directory contents");
add_command(&ls_cmd);
+
+ parent_cmd.oneline = _("list parent pointers");
+ add_command(&parent_cmd);
}
diff --git a/man/man8/xfs_db.8 b/man/man8/xfs_db.8
index a7f6d55ed..937b17e79 100644
--- a/man/man8/xfs_db.8
+++ b/man/man8/xfs_db.8
@@ -943,6 +943,15 @@ See the
.B print
command.
.TP
+.BI "parent [" paths "]..."
+List the parents of a file.
+If a path resolves to a file, the parents of that file will be listed.
+If no paths are supplied and the IO cursor points at an inode, the parents of
+that file will be listed.
+
+The output format is:
+inode number, inode generation, ondisk namehash, namehash, name length, name.
+.TP
.BI "path " dir_path
Walk the directory tree to an inode using the supplied path.
Absolute and relative paths are supported.
