[RFC PATCH v11 48/51] ceph: add fscrypt decryption support to ceph_netfs_issue_op

Jeff Layton
2022-03-22T14:17:19Z

Force the use of sparse reads when the inode is encrypted, and add the
appropriate code to decrypt the extent map after receiving.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
fs/ceph/addr.c | 32 +++++++++++++++++++++++---------
1 file changed, 23 insertions(+), 9 deletions(-)

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 15bc455bc87f..13a37a568a1d 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -18,6 +18,7 @@
#include "mds_client.h"
#include "cache.h"
#include "metric.h"
+#include "crypto.h"
#include <linux/ceph/osd_client.h>
#include <linux/ceph/striper.h>

@@ -217,7 +218,8 @@ static bool ceph_netfs_clamp_length(struct netfs_read_subrequest *subreq)

static void finish_netfs_read(struct ceph_osd_request *req)
{
- struct ceph_fs_client *fsc = ceph_inode_to_client(req->r_inode);
+ struct inode *inode = req->r_inode;
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
struct netfs_read_subrequest *subreq = req->r_priv;
struct ceph_osd_req_op *op = &req->r_ops[0];
@@ -232,15 +234,24 @@ static void finish_netfs_read(struct ceph_osd_request *req)
subreq->len, i_size_read(req->r_inode));

/* no object means success but no data */
- if (sparse && err >= 0)
- err = ceph_sparse_ext_map_end(op);
- else if (err == -ENOENT)
+ if (err == -ENOENT)
err = 0;
else if (err == -EBLOCKLISTED)
fsc->blocklisted = true;

- if (err >= 0 && err < subreq->len)
- __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
+ if (err >= 0) {
+ if (sparse && err > 0)
+ err = ceph_sparse_ext_map_end(op);
+ if (err < subreq->len)
+ __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
+ if (IS_ENCRYPTED(inode) && err > 0) {
+ err = ceph_fscrypt_decrypt_extents(inode, osd_data->pages,
+ subreq->start, op->extent.sparse_ext,
+ op->extent.sparse_ext_cnt);
+ if (err > subreq->len)
+ err = subreq->len;
+ }
+ }

netfs_subreq_terminated(subreq, err, true);

@@ -315,13 +326,16 @@ static void ceph_netfs_issue_op(struct netfs_read_subrequest *subreq)
size_t page_off;
int err = 0;
u64 len = subreq->len;
- bool sparse = ceph_test_mount_opt(fsc, SPARSEREAD);
+ bool sparse = IS_ENCRYPTED(inode) || ceph_test_mount_opt(fsc, SPARSEREAD);
+ u64 off = subreq->start;

if (ci->i_inline_version != CEPH_INLINE_NONE &&
ceph_netfs_issue_op_inline(subreq))
return;

- req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, vino, subreq->start, &len,
+ ceph_fscrypt_adjust_off_and_len(inode, &off, &len);
+
+ req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, vino, off, &len,
0, 1, sparse ? CEPH_OSD_OP_SPARSE_READ : CEPH_OSD_OP_READ,
CEPH_OSD_FLAG_READ | fsc->client->osdc.client->options->read_from_replica,
NULL, ci->i_truncate_seq, ci->i_truncate_size, false);
@@ -341,7 +355,7 @@ static void ceph_netfs_issue_op(struct netfs_read_subrequest *subreq)
}

dout("%s: pos=%llu orig_len=%zu len=%llu\n", __func__, subreq->start, subreq->len, len);
- iov_iter_xarray(&iter, READ, &rreq->mapping->i_pages, subreq->start, len);
+ iov_iter_xarray(&iter, READ, &rreq->mapping->i_pages, off, len);
err = iov_iter_get_pages_alloc(&iter, &pages, len, &page_off);
if (err < 0) {
dout("%s: iov_ter_get_pages_alloc returned %d\n", __func__, err);
--
2.35.1