Tidy up the server-side XDR encoders for READDIR results and
directory entries. Series applies to nfsd-next. See topic branch
"nfsd4-encoder-overhaul" in this repo:
https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git
---
Chuck Lever (5):
NFSD: Rename nfsd4_encode_dirent()
NFSD: Clean up nfsd4_encode_rdattr_error()
NFSD: Add an nfsd4_encode_nfs_cookie4() helper
NFSD: Clean up nfsd4_encode_entry4()
NFSD: Clean up nfsd4_encode_readdir()
fs/nfsd/nfs4xdr.c | 200 +++++++++++++++++++++++-----------------------
fs/nfsd/xdr4.h | 3 +
2 files changed, 104 insertions(+), 99 deletions(-)
--
Chuck Lever
From: Chuck Lever <[email protected]>
Untangle nfsd4_encode_readdir() so it is more clear what XDR data
item is being encoded by which piece of code.
Signed-off-by: Chuck Lever <[email protected]>
---
fs/nfsd/nfs4xdr.c | 112 ++++++++++++++++++++++++++---------------------------
1 file changed, 55 insertions(+), 57 deletions(-)
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index cfc8e241e8fb..5efcd9691e5d 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -4448,85 +4448,83 @@ nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr,
return nfserr;
}
-static __be32
-nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr,
- union nfsd4_op_u *u)
+static __be32 nfsd4_encode_dirlist4(struct xdr_stream *xdr,
+ struct nfsd4_readdir *readdir,
+ u32 max_payload)
{
- struct nfsd4_readdir *readdir = &u->readdir;
- int maxcount;
- int bytes_left;
+ int bytes_left, maxcount, starting_len = xdr->buf->len;
loff_t offset;
- struct xdr_stream *xdr = resp->xdr;
- int starting_len = xdr->buf->len;
- __be32 *p;
-
- nfserr = nfsd4_encode_verifier4(xdr, &readdir->rd_verf);
- if (nfserr != nfs_ok)
- return nfserr;
+ __be32 status;
/*
* Number of bytes left for directory entries allowing for the
- * final 8 bytes of the readdir and a following failed op:
+ * final 8 bytes of the readdir and a following failed op.
*/
- bytes_left = xdr->buf->buflen - xdr->buf->len
- - COMPOUND_ERR_SLACK_SPACE - 8;
- if (bytes_left < 0) {
- nfserr = nfserr_resource;
- goto err_no_verf;
- }
- maxcount = svc_max_payload(resp->rqstp);
- maxcount = min_t(u32, readdir->rd_maxcount, maxcount);
+ bytes_left = xdr->buf->buflen - xdr->buf->len -
+ COMPOUND_ERR_SLACK_SPACE - XDR_UNIT * 2;
+ if (bytes_left < 0)
+ return nfserr_resource;
+ maxcount = min_t(u32, readdir->rd_maxcount, max_payload);
+
/*
- * Note the rfc defines rd_maxcount as the size of the
- * READDIR4resok structure, which includes the verifier above
- * and the 8 bytes encoded at the end of this function:
+ * The RFC defines rd_maxcount as the size of the
+ * READDIR4resok structure, which includes the verifier
+ * and the 8 bytes encoded at the end of this function.
*/
- if (maxcount < 16) {
- nfserr = nfserr_toosmall;
- goto err_no_verf;
- }
- maxcount = min_t(int, maxcount-16, bytes_left);
+ if (maxcount < XDR_UNIT * 4)
+ return nfserr_toosmall;
+ maxcount = min_t(int, maxcount - XDR_UNIT * 4, bytes_left);
- /* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
+ /* RFC 3530 14.2.24 allows us to ignore dircount when it's 0 */
if (!readdir->rd_dircount)
- readdir->rd_dircount = svc_max_payload(resp->rqstp);
+ readdir->rd_dircount = max_payload;
+ /* *entries */
readdir->xdr = xdr;
readdir->rd_maxcount = maxcount;
readdir->common.err = 0;
readdir->cookie_offset = 0;
-
offset = readdir->rd_cookie;
- nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp, &offset,
+ status = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp, &offset,
&readdir->common, nfsd4_encode_entry4);
- if (nfserr == nfs_ok &&
- readdir->common.err == nfserr_toosmall &&
- xdr->buf->len == starting_len + 8) {
- /* nothing encoded; which limit did we hit?: */
- if (maxcount - 16 < bytes_left)
- /* It was the fault of rd_maxcount: */
- nfserr = nfserr_toosmall;
- else
- /* We ran out of buffer space: */
- nfserr = nfserr_resource;
+ if (status)
+ return status;
+ if (readdir->common.err == nfserr_toosmall &&
+ xdr->buf->len == starting_len) {
+ /* No entries were encoded. Which limit did we hit? */
+ if (maxcount - XDR_UNIT * 4 < bytes_left)
+ /* It was the fault of rd_maxcount */
+ return nfserr_toosmall;
+ /* We ran out of buffer space */
+ return nfserr_resource;
}
- if (nfserr)
- goto err_no_verf;
-
/* Encode the final entry's cookie value */
nfsd4_encode_entry4_nfs_cookie4(readdir, offset);
+ /* No entries follow */
+ if (xdr_stream_encode_item_absent(xdr) != XDR_UNIT)
+ return nfserr_resource;
- p = xdr_reserve_space(xdr, 8);
- if (!p) {
- WARN_ON_ONCE(1);
- goto err_no_verf;
- }
- *p++ = 0; /* no more entries */
- *p++ = htonl(readdir->common.err == nfserr_eof);
+ /* eof */
+ return nfsd4_encode_bool(xdr, readdir->common.err == nfserr_eof);
+}
- return 0;
-err_no_verf:
- xdr_truncate_encode(xdr, starting_len);
+static __be32
+nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr,
+ union nfsd4_op_u *u)
+{
+ struct nfsd4_readdir *readdir = &u->readdir;
+ struct xdr_stream *xdr = resp->xdr;
+ int starting_len = xdr->buf->len;
+
+ /* cookieverf */
+ nfserr = nfsd4_encode_verifier4(xdr, &readdir->rd_verf);
+ if (nfserr != nfs_ok)
+ return nfserr;
+
+ /* reply */
+ nfserr = nfsd4_encode_dirlist4(xdr, readdir, svc_max_payload(resp->rqstp));
+ if (nfserr != nfs_ok)
+ xdr_truncate_encode(xdr, starting_len);
return nfserr;
}
From: Chuck Lever <[email protected]>
Reshape nfsd4_encode_entry4() to be more like the legacy dirent
encoders, which were recently rewritten to use xdr_stream.
Signed-off-by: Chuck Lever <[email protected]>
---
fs/nfsd/nfs4xdr.c | 15 ++++++---------
fs/nfsd/xdr4.h | 3 +++
2 files changed, 9 insertions(+), 9 deletions(-)
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 3eba3f316d97..cfc8e241e8fb 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3768,7 +3768,6 @@ nfsd4_encode_entry4(void *ccdv, const char *name, int namlen,
u32 name_and_cookie;
int entry_bytes;
__be32 nfserr = nfserr_toosmall;
- __be32 *p;
/* In nfsv4, "." and ".." never make it onto the wire.. */
if (name && isdotent(name, namlen)) {
@@ -3779,17 +3778,15 @@ nfsd4_encode_entry4(void *ccdv, const char *name, int namlen,
/* Encode the previous entry's cookie value */
nfsd4_encode_entry4_nfs_cookie4(cd, offset);
- p = xdr_reserve_space(xdr, 4);
- if (!p)
+ if (xdr_stream_encode_item_present(xdr) != XDR_UNIT)
goto fail;
- *p++ = xdr_one; /* mark entry present */
+
+ /* Reserve send buffer space for this entry's cookie value. */
cookie_offset = xdr->buf->len;
- p = xdr_reserve_space(xdr, 3*4 + namlen);
- if (!p)
+ if (nfsd4_encode_nfs_cookie4(xdr, OFFSET_MAX) != nfs_ok)
+ goto fail;
+ if (nfsd4_encode_component4(xdr, name, namlen) != nfs_ok)
goto fail;
- p = xdr_encode_hyper(p, OFFSET_MAX); /* offset of next entry */
- p = xdr_encode_array(p, name, namlen); /* name length & name */
-
nfserr = nfsd4_encode_entry4_fattr(cd, name, namlen);
switch (nfserr) {
case nfs_ok:
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index cd124969589e..6f5c3f4b4ca3 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -120,6 +120,7 @@ nfsd4_encode_uint64_t(struct xdr_stream *xdr, u64 val)
}
#define nfsd4_encode_changeid4(x, v) nfsd4_encode_uint64_t(x, v)
+#define nfsd4_encode_nfs_cookie4(x, v) nfsd4_encode_uint64_t(x, v)
#define nfsd4_encode_length4(x, v) nfsd4_encode_uint64_t(x, v)
#define nfsd4_encode_offset4(x, v) nfsd4_encode_uint64_t(x, v)
@@ -174,6 +175,8 @@ nfsd4_encode_opaque(struct xdr_stream *xdr, const void *data, size_t size)
return nfs_ok;
}
+#define nfsd4_encode_component4(x, d, s) nfsd4_encode_opaque(x, d, s)
+
struct nfsd4_compound_state {
struct svc_fh current_fh;
struct svc_fh save_fh;
On Wed, 2023-10-04 at 09:41 -0400, Chuck Lever wrote:
> Tidy up the server-side XDR encoders for READDIR results and
> directory entries. Series applies to nfsd-next. See topic branch
> "nfsd4-encoder-overhaul" in this repo:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git
>
> ---
>
> Chuck Lever (5):
> NFSD: Rename nfsd4_encode_dirent()
> NFSD: Clean up nfsd4_encode_rdattr_error()
> NFSD: Add an nfsd4_encode_nfs_cookie4() helper
> NFSD: Clean up nfsd4_encode_entry4()
> NFSD: Clean up nfsd4_encode_readdir()
>
>
> fs/nfsd/nfs4xdr.c | 200 +++++++++++++++++++++++-----------------------
> fs/nfsd/xdr4.h | 3 +
> 2 files changed, 104 insertions(+), 99 deletions(-)
>
> --
> Chuck Lever
>
Reviewed-by: Jeff Layton <[email protected]>