[16/64] xfs: split new inode creation into two pieces

Commit Message

Darrick J. Wong Oct. 2, 2024, 1:12 a.m. UTC

From: Darrick J. Wong <[e-mail]>

Source kernel commit: 38fd3d6a956f1b104f11cd6eee116c54bfe458c4

There are two parts to initializing a newly allocated inode: setting up
the incore structures, and initializing the new inode core based on the
parent inode and the current user's environment.  The initialization
code is not specific to the kernel, so we would like to share that with
userspace by hoisting it to libxfs.  Therefore, split xfs_icreate into
separate functions to prepare for the next few patches.

Signed-off-by: Darrick J. Wong <[e-mail]>
Reviewed-by: Christoph Hellwig <[e-mail]>
---
 libxfs/xfs_ialloc.c |   15 +++++++++++++++
 1 file changed, 15 insertions(+)

Patch

diff --git a/libxfs/xfs_ialloc.c b/libxfs/xfs_ialloc.c
index d8697561e..cef2819aa 100644
--- a/libxfs/xfs_ialloc.c
+++ b/libxfs/xfs_ialloc.c
@@ -1941,6 +1941,21 @@  xfs_dialloc(
 		}
 		return -ENOSPC;
 	}
+
+	/*
+	 * Protect against obviously corrupt allocation btree records. Later
+	 * xfs_iget checks will catch re-allocation of other active in-memory
+	 * and on-disk inodes. If we don't catch reallocating the parent inode
+	 * here we will deadlock in xfs_iget() so we have to do these checks
+	 * first.
+	 */
+	if (ino == parent || !xfs_verify_dir_ino(mp, ino)) {
+		xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino);
+		xfs_agno_mark_sick(mp, XFS_INO_TO_AGNO(mp, ino),
+				XFS_SICK_AG_INOBT);
+		return -EFSCORRUPTED;
+	}
+
 	*new_ino = ino;
 	return 0;
 }