[PATCH 06/10] afs: Improve dir check failure reports

From: David Howells
Date: Fri Mar 15 2019 - 19:07:36 EST


Improve the content of directory check failure reports from:

kAFS: afs_dir_check_page(6d57): bad magic 1/2 is 0000

to dump more information about the individual blocks in a directory page.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

fs/afs/dir.c | 38 ++++++++++++++++++++++++++++++++++----
1 file changed, 34 insertions(+), 4 deletions(-)

diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index 8a2562e3a316..378a96a1116e 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -159,6 +159,38 @@ static bool afs_dir_check_page(struct afs_vnode *dvnode, struct page *page,
return false;
}

+/*
+ * Check the contents of a directory that we've just read.
+ */
+static bool afs_dir_check_pages(struct afs_vnode *dvnode, struct afs_read *req)
+{
+ struct afs_xdr_dir_page *dbuf;
+ unsigned int i, j, qty = PAGE_SIZE / sizeof(union afs_xdr_dir_block);
+
+ for (i = 0; i < req->nr_pages; i++)
+ if (!afs_dir_check_page(dvnode, req->pages[i], req->actual_len))
+ goto bad;
+ return true;
+
+bad:
+ pr_warn("DIR %llx:%llx f=%llx l=%llx al=%llx r=%llx\n",
+ dvnode->fid.vid, dvnode->fid.vnode,
+ req->file_size, req->len, req->actual_len, req->remain);
+ pr_warn("DIR %llx %x %x %x\n",
+ req->pos, req->index, req->nr_pages, req->offset);
+
+ for (i = 0; i < req->nr_pages; i++) {
+ dbuf = kmap(req->pages[i]);
+ for (j = 0; j < qty; j++) {
+ union afs_xdr_dir_block *block = &dbuf->blocks[j];
+
+ pr_warn("[%02x] %32phN\n", i * qty + j, block);
+ }
+ kunmap(req->pages[i]);
+ }
+ return false;
+}
+
/*
* open an AFS directory file
*/
@@ -288,10 +320,8 @@ static struct afs_read *afs_read_dir(struct afs_vnode *dvnode, struct key *key)

/* Validate the data we just read. */
ret = -EIO;
- for (i = 0; i < req->nr_pages; i++)
- if (!afs_dir_check_page(dvnode, req->pages[i],
- req->actual_len))
- goto error_unlock;
+ if (!afs_dir_check_pages(dvnode, req))
+ goto error_unlock;

// TODO: Trim excess pages