From 4aceaaea5eccd32bc40c6c76b262489b2f53ca8d Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Tue, 10 Nov 2020 10:56:53 -0500
Subject: SUNRPC: Fix up open coded kmemdup_nul()

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 71e03b930b70..b1cda6d85ded 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1942,10 +1942,8 @@ ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str,
 
 	ret = xdr_stream_decode_opaque_inline(xdr, &p, maxlen);
 	if (ret > 0) {
-		char *s = kmalloc(ret + 1, gfp_flags);
+		char *s = kmemdup_nul(p, ret, gfp_flags);
 		if (s != NULL) {
-			memcpy(s, p, ret);
-			s[ret] = '\0';
 			*str = s;
 			return strlen(s);
 		}
-- 
cgit v1.2.3


From 2b1f83d108bd35d12d8a833298d2a033f9121aac Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Sat, 21 Nov 2020 14:01:50 -0500
Subject: SUNRPC: Fix up typo in xdr_init_decode()

We already know that the head buffer and page are empty, so if there is
any data, it is in the tail.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index b1cda6d85ded..bc7a622016ee 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1060,7 +1060,7 @@ void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p,
 	else if (buf->page_len != 0)
 		xdr_set_page_base(xdr, 0, buf->len);
 	else
-		xdr_set_iov(xdr, buf->head, buf->len);
+		xdr_set_iov(xdr, buf->tail, buf->len);
 	if (p != NULL && p > xdr->p && xdr->end >= p) {
 		xdr->nwords -= p - xdr->p;
 		xdr->p = p;
-- 
cgit v1.2.3


From 8d86e373b0ef52d091ced9583ffbb33ad2771576 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Sat, 21 Nov 2020 14:50:43 -0500
Subject: SUNRPC: Clean up helpers xdr_set_iov() and xdr_set_page_base()

Allow xdr_set_iov() to set a base so that we can use it to set the
cursor to a specific position in the kvec buffer.

If the new base overflows the kvec/pages buffer in either xdr_set_iov()
or xdr_set_page_base(), then truncate it so that we point to the end of
the buffer.

Finally, change both function to return the number of bytes remaining to
read in their buffers.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 36 +++++++++++++++++++-----------------
 1 file changed, 19 insertions(+), 17 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index bc7a622016ee..394297ec1cb9 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -970,19 +970,22 @@ void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int b
 }
 EXPORT_SYMBOL_GPL(xdr_write_pages);
 
-static void xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov,
-		unsigned int len)
+static unsigned int xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov,
+				unsigned int base, unsigned int len)
 {
 	if (len > iov->iov_len)
 		len = iov->iov_len;
-	xdr->p = (__be32*)iov->iov_base;
+	if (unlikely(base > len))
+		base = len;
+	xdr->p = (__be32*)(iov->iov_base + base);
 	xdr->end = (__be32*)(iov->iov_base + len);
 	xdr->iov = iov;
 	xdr->page_ptr = NULL;
+	return len - base;
 }
 
-static int xdr_set_page_base(struct xdr_stream *xdr,
-		unsigned int base, unsigned int len)
+static unsigned int xdr_set_page_base(struct xdr_stream *xdr,
+				      unsigned int base, unsigned int len)
 {
 	unsigned int pgnr;
 	unsigned int maxlen;
@@ -991,9 +994,11 @@ static int xdr_set_page_base(struct xdr_stream *xdr,
 	void *kaddr;
 
 	maxlen = xdr->buf->page_len;
-	if (base >= maxlen)
-		return -EINVAL;
-	maxlen -= base;
+	if (base >= maxlen) {
+		base = maxlen;
+		maxlen = 0;
+	} else
+		maxlen -= base;
 	if (len > maxlen)
 		len = maxlen;
 
@@ -1011,14 +1016,14 @@ static int xdr_set_page_base(struct xdr_stream *xdr,
 		pgend = PAGE_SIZE;
 	xdr->end = (__be32*)(kaddr + pgend);
 	xdr->iov = NULL;
-	return 0;
+	return len;
 }
 
 static void xdr_set_page(struct xdr_stream *xdr, unsigned int base,
 			 unsigned int len)
 {
-	if (xdr_set_page_base(xdr, base, len) < 0)
-		xdr_set_iov(xdr, xdr->buf->tail, xdr->nwords << 2);
+	if (xdr_set_page_base(xdr, base, len) == 0)
+		xdr_set_iov(xdr, xdr->buf->tail, 0, xdr_stream_remaining(xdr));
 }
 
 static void xdr_set_next_page(struct xdr_stream *xdr)
@@ -1055,12 +1060,9 @@ void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p,
 	xdr->scratch.iov_base = NULL;
 	xdr->scratch.iov_len = 0;
 	xdr->nwords = XDR_QUADLEN(buf->len);
-	if (buf->head[0].iov_len != 0)
-		xdr_set_iov(xdr, buf->head, buf->len);
-	else if (buf->page_len != 0)
-		xdr_set_page_base(xdr, 0, buf->len);
-	else
-		xdr_set_iov(xdr, buf->tail, buf->len);
+	if (xdr_set_iov(xdr, buf->head, 0, buf->len) == 0 &&
+	    xdr_set_page_base(xdr, 0, buf->len) == 0)
+		xdr_set_iov(xdr, buf->tail, 0, buf->len);
 	if (p != NULL && p > xdr->p && xdr->end >= p) {
 		xdr->nwords -= p - xdr->p;
 		xdr->p = p;
-- 
cgit v1.2.3


From 1d97316692f708de755655ac1cfd704d7a55843f Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Fri, 20 Nov 2020 16:31:03 -0500
Subject: SUNRPC: Fix up xdr_read_pages() to take arbitrary object lengths

Fix up xdr_read_pages() so that it can handle object lengths that are
larger than the page length, by simply aligning to the next object in
the buffer tail.
The function will continue to return the length of the truncate object
data that actually fit into the pages.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 41 +++++++++++++++--------------------------
 1 file changed, 15 insertions(+), 26 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 394297ec1cb9..3ce0a5daa9eb 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1219,44 +1219,33 @@ static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
 }
 
 /**
- * xdr_read_pages - Ensure page-based XDR data to decode is aligned at current pointer position
+ * xdr_read_pages - align page-based XDR data to current pointer position
  * @xdr: pointer to xdr_stream struct
  * @len: number of bytes of page data
  *
  * Moves data beyond the current pointer position from the XDR head[] buffer
- * into the page list. Any data that lies beyond current position + "len"
- * bytes is moved into the XDR tail[].
+ * into the page list. Any data that lies beyond current position + @len
+ * bytes is moved into the XDR tail[]. The xdr_stream current position is
+ * then advanced past that data to align to the next XDR object in the tail.
  *
  * Returns the number of XDR encoded bytes now contained in the pages
  */
 unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
 {
-	struct xdr_buf *buf = xdr->buf;
-	struct kvec *iov;
-	unsigned int nwords;
-	unsigned int end;
-	unsigned int padding;
+	unsigned int nwords = XDR_QUADLEN(len);
+	unsigned int base, end, pglen;
 
-	len = xdr_align_pages(xdr, len);
-	if (len == 0)
+	pglen = xdr_align_pages(xdr, nwords << 2);
+	if (pglen == 0)
 		return 0;
-	nwords = XDR_QUADLEN(len);
-	padding = (nwords << 2) - len;
-	xdr->iov = iov = buf->tail;
-	/* Compute remaining message length.  */
-	end = ((xdr->nwords - nwords) << 2) + padding;
-	if (end > iov->iov_len)
-		end = iov->iov_len;
 
-	/*
-	 * Position current pointer at beginning of tail, and
-	 * set remaining message length.
-	 */
-	xdr->p = (__be32 *)((char *)iov->iov_base + padding);
-	xdr->end = (__be32 *)((char *)iov->iov_base + end);
-	xdr->page_ptr = NULL;
-	xdr->nwords = XDR_QUADLEN(end - padding);
-	return len;
+	xdr->nwords -= nwords;
+	base = (nwords << 2) - pglen;
+	end = xdr_stream_remaining(xdr) - pglen;
+
+	if (xdr_set_iov(xdr, xdr->buf->tail, base, end) == 0)
+		xdr->nwords = 0;
+	return len <= pglen ? len : pglen;
 }
 EXPORT_SYMBOL_GPL(xdr_read_pages);
 
-- 
cgit v1.2.3


From 9ed5af268e88f6e5b65376be98d652b37cb20d7b Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Sat, 21 Nov 2020 20:46:18 -0500
Subject: SUNRPC: Clean up the handling of page padding in
 rpc_prepare_reply_pages()

rpc_prepare_reply_pages() currently expects the 'hdrsize' argument to
contain the length of the data that we expect to want placed in the head
kvec plus a count of 1 word of padding that is placed after the page data.
This is very confusing when trying to read the code, and sometimes leads
to callers adding an arbitrary value of '1' just in order to satisfy the
requirement (whether or not the page data actually needs such padding).

This patch aims to clarify the code by changing the 'hdrsize' argument
to remove that 1 word of padding. This means we need to subtract the
padding from all the existing callers.

Fixes: 02ef04e432ba ("NFS: Account for XDR pad of buf->pages")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 fs/nfs/nfs2xdr.c  | 19 ++++++++++---------
 fs/nfs/nfs3xdr.c  | 29 ++++++++++++++++-------------
 fs/nfs/nfs4xdr.c  | 36 +++++++++++++++++++-----------------
 net/sunrpc/clnt.c |  5 +----
 net/sunrpc/xdr.c  |  3 ---
 5 files changed, 46 insertions(+), 46 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c
index f6676af37d5d..7fba7711e6b3 100644
--- a/fs/nfs/nfs2xdr.c
+++ b/fs/nfs/nfs2xdr.c
@@ -34,6 +34,7 @@
  * Declare the space requirements for NFS arguments and replies as
  * number of 32bit-words
  */
+#define NFS_pagepad_sz		(1) /* Page padding */
 #define NFS_fhandle_sz		(8)
 #define NFS_sattr_sz		(8)
 #define NFS_filename_sz		(1+(NFS2_MAXNAMLEN>>2))
@@ -56,11 +57,11 @@
 
 #define NFS_attrstat_sz		(1+NFS_fattr_sz)
 #define NFS_diropres_sz		(1+NFS_fhandle_sz+NFS_fattr_sz)
-#define NFS_readlinkres_sz	(2+1)
-#define NFS_readres_sz		(1+NFS_fattr_sz+1+1)
+#define NFS_readlinkres_sz	(2+NFS_pagepad_sz)
+#define NFS_readres_sz		(1+NFS_fattr_sz+1+NFS_pagepad_sz)
 #define NFS_writeres_sz         (NFS_attrstat_sz)
 #define NFS_stat_sz		(1)
-#define NFS_readdirres_sz	(1+1)
+#define NFS_readdirres_sz	(1+NFS_pagepad_sz)
 #define NFS_statfsres_sz	(1+NFS_info_sz)
 
 static int nfs_stat_to_errno(enum nfs_stat);
@@ -592,8 +593,8 @@ static void nfs2_xdr_enc_readlinkargs(struct rpc_rqst *req,
 	const struct nfs_readlinkargs *args = data;
 
 	encode_fhandle(xdr, args->fh);
-	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
-				args->pglen, NFS_readlinkres_sz);
+	rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->pglen,
+				NFS_readlinkres_sz - NFS_pagepad_sz);
 }
 
 /*
@@ -628,8 +629,8 @@ static void nfs2_xdr_enc_readargs(struct rpc_rqst *req,
 	const struct nfs_pgio_args *args = data;
 
 	encode_readargs(xdr, args);
-	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
-				args->count, NFS_readres_sz);
+	rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->count,
+				NFS_readres_sz - NFS_pagepad_sz);
 	req->rq_rcv_buf.flags |= XDRBUF_READ;
 }
 
@@ -786,8 +787,8 @@ static void nfs2_xdr_enc_readdirargs(struct rpc_rqst *req,
 	const struct nfs_readdirargs *args = data;
 
 	encode_readdirargs(xdr, args);
-	rpc_prepare_reply_pages(req, args->pages, 0,
-				args->count, NFS_readdirres_sz);
+	rpc_prepare_reply_pages(req, args->pages, 0, args->count,
+				NFS_readdirres_sz - NFS_pagepad_sz);
 }
 
 /*
diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index 69971f6c840d..ca10072644ff 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -33,6 +33,7 @@
  * Declare the space requirements for NFS arguments and replies as
  * number of 32bit-words
  */
+#define NFS3_pagepad_sz		(1) /* Page padding */
 #define NFS3_fhandle_sz		(1+16)
 #define NFS3_fh_sz		(NFS3_fhandle_sz)	/* shorthand */
 #define NFS3_sattr_sz		(15)
@@ -69,13 +70,13 @@
 #define NFS3_removeres_sz	(NFS3_setattrres_sz)
 #define NFS3_lookupres_sz	(1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz))
 #define NFS3_accessres_sz	(1+NFS3_post_op_attr_sz+1)
-#define NFS3_readlinkres_sz	(1+NFS3_post_op_attr_sz+1+1)
-#define NFS3_readres_sz		(1+NFS3_post_op_attr_sz+3+1)
+#define NFS3_readlinkres_sz	(1+NFS3_post_op_attr_sz+1+NFS3_pagepad_sz)
+#define NFS3_readres_sz		(1+NFS3_post_op_attr_sz+3+NFS3_pagepad_sz)
 #define NFS3_writeres_sz	(1+NFS3_wcc_data_sz+4)
 #define NFS3_createres_sz	(1+NFS3_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
 #define NFS3_renameres_sz	(1+(2 * NFS3_wcc_data_sz))
 #define NFS3_linkres_sz		(1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
-#define NFS3_readdirres_sz	(1+NFS3_post_op_attr_sz+2+1)
+#define NFS3_readdirres_sz	(1+NFS3_post_op_attr_sz+2+NFS3_pagepad_sz)
 #define NFS3_fsstatres_sz	(1+NFS3_post_op_attr_sz+13)
 #define NFS3_fsinfores_sz	(1+NFS3_post_op_attr_sz+12)
 #define NFS3_pathconfres_sz	(1+NFS3_post_op_attr_sz+6)
@@ -85,7 +86,8 @@
 #define ACL3_setaclargs_sz	(NFS3_fh_sz+1+ \
 				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
 #define ACL3_getaclres_sz	(1+NFS3_post_op_attr_sz+1+ \
-				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)+1)
+				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)+\
+				NFS3_pagepad_sz)
 #define ACL3_setaclres_sz	(1+NFS3_post_op_attr_sz)
 
 static int nfs3_stat_to_errno(enum nfs_stat);
@@ -909,8 +911,8 @@ static void nfs3_xdr_enc_readlink3args(struct rpc_rqst *req,
 	const struct nfs3_readlinkargs *args = data;
 
 	encode_nfs_fh3(xdr, args->fh);
-	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
-				args->pglen, NFS3_readlinkres_sz);
+	rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->pglen,
+				NFS3_readlinkres_sz - NFS3_pagepad_sz);
 }
 
 /*
@@ -939,7 +941,8 @@ static void nfs3_xdr_enc_read3args(struct rpc_rqst *req,
 				   const void *data)
 {
 	const struct nfs_pgio_args *args = data;
-	unsigned int replen = args->replen ? args->replen : NFS3_readres_sz;
+	unsigned int replen = args->replen ? args->replen :
+					     NFS3_readres_sz - NFS3_pagepad_sz;
 
 	encode_read3args(xdr, args);
 	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
@@ -1239,8 +1242,8 @@ static void nfs3_xdr_enc_readdir3args(struct rpc_rqst *req,
 	const struct nfs3_readdirargs *args = data;
 
 	encode_readdir3args(xdr, args);
-	rpc_prepare_reply_pages(req, args->pages, 0,
-				args->count, NFS3_readdirres_sz);
+	rpc_prepare_reply_pages(req, args->pages, 0, args->count,
+				NFS3_readdirres_sz - NFS3_pagepad_sz);
 }
 
 /*
@@ -1281,8 +1284,8 @@ static void nfs3_xdr_enc_readdirplus3args(struct rpc_rqst *req,
 	const struct nfs3_readdirargs *args = data;
 
 	encode_readdirplus3args(xdr, args);
-	rpc_prepare_reply_pages(req, args->pages, 0,
-				args->count, NFS3_readdirres_sz);
+	rpc_prepare_reply_pages(req, args->pages, 0, args->count,
+				NFS3_readdirres_sz - NFS3_pagepad_sz);
 }
 
 /*
@@ -1328,7 +1331,7 @@ static void nfs3_xdr_enc_getacl3args(struct rpc_rqst *req,
 	if (args->mask & (NFS_ACL | NFS_DFACL)) {
 		rpc_prepare_reply_pages(req, args->pages, 0,
 					NFSACL_MAXPAGES << PAGE_SHIFT,
-					ACL3_getaclres_sz);
+					ACL3_getaclres_sz - NFS3_pagepad_sz);
 		req->rq_rcv_buf.flags |= XDRBUF_SPARSE_PAGES;
 	}
 }
@@ -1648,7 +1651,7 @@ static int nfs3_xdr_dec_read3res(struct rpc_rqst *req, struct xdr_stream *xdr,
 	result->op_status = status;
 	if (status != NFS3_OK)
 		goto out_status;
-	result->replen = 4 + ((xdr_stream_pos(xdr) - pos) >> 2);
+	result->replen = 3 + ((xdr_stream_pos(xdr) - pos) >> 2);
 	error = decode_read3resok(xdr, result);
 out:
 	return error;
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index c16b93df1bc1..3899ef3047f4 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -84,6 +84,7 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req,
 /* lock,open owner id:
  * we currently use size 2 (u64) out of (NFS4_OPAQUE_LIMIT  >> 2)
  */
+#define pagepad_maxsz		(1)
 #define open_owner_id_maxsz	(1 + 2 + 1 + 1 + 2)
 #define lock_owner_id_maxsz	(1 + 1 + 4)
 #define decode_lockowner_maxsz	(1 + XDR_QUADLEN(IDMAP_NAMESZ))
@@ -215,14 +216,14 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req,
 				 nfs4_fattr_bitmap_maxsz)
 #define encode_read_maxsz	(op_encode_hdr_maxsz + \
 				 encode_stateid_maxsz + 3)
-#define decode_read_maxsz	(op_decode_hdr_maxsz + 2 + 1)
+#define decode_read_maxsz	(op_decode_hdr_maxsz + 2 + pagepad_maxsz)
 #define encode_readdir_maxsz	(op_encode_hdr_maxsz + \
 				 2 + encode_verifier_maxsz + 5 + \
 				nfs4_label_maxsz)
 #define decode_readdir_maxsz	(op_decode_hdr_maxsz + \
-				 decode_verifier_maxsz + 1)
+				 decode_verifier_maxsz + pagepad_maxsz)
 #define encode_readlink_maxsz	(op_encode_hdr_maxsz)
-#define decode_readlink_maxsz	(op_decode_hdr_maxsz + 1 + 1)
+#define decode_readlink_maxsz	(op_decode_hdr_maxsz + 1 + pagepad_maxsz)
 #define encode_write_maxsz	(op_encode_hdr_maxsz + \
 				 encode_stateid_maxsz + 4)
 #define decode_write_maxsz	(op_decode_hdr_maxsz + \
@@ -284,14 +285,14 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req,
 #define decode_delegreturn_maxsz (op_decode_hdr_maxsz)
 #define encode_getacl_maxsz	(encode_getattr_maxsz)
 #define decode_getacl_maxsz	(op_decode_hdr_maxsz + \
-				 nfs4_fattr_bitmap_maxsz + 1 + 1)
+				 nfs4_fattr_bitmap_maxsz + 1 + pagepad_maxsz)
 #define encode_setacl_maxsz	(op_encode_hdr_maxsz + \
 				 encode_stateid_maxsz + 3)
 #define decode_setacl_maxsz	(decode_setattr_maxsz)
 #define encode_fs_locations_maxsz \
 				(encode_getattr_maxsz)
 #define decode_fs_locations_maxsz \
-				(1)
+				(pagepad_maxsz)
 #define encode_secinfo_maxsz	(op_encode_hdr_maxsz + nfs4_name_maxsz)
 #define decode_secinfo_maxsz	(op_decode_hdr_maxsz + 1 + ((NFS_MAX_SECFLAVORS * (16 + GSS_OID_MAX_LEN)) / 4))
 
@@ -393,12 +394,13 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req,
 				  /* devaddr4 payload is read into page */ \
 				1 /* notification bitmap length */ + \
 				1 /* notification bitmap, word 0 */ + \
-				1 /* possible XDR padding */)
+				pagepad_maxsz /* possible XDR padding */)
 #define encode_layoutget_maxsz	(op_encode_hdr_maxsz + 10 + \
 				encode_stateid_maxsz)
 #define decode_layoutget_maxsz	(op_decode_hdr_maxsz + 8 + \
 				decode_stateid_maxsz + \
-				XDR_QUADLEN(PNFS_LAYOUT_MAXSIZE) + 1)
+				XDR_QUADLEN(PNFS_LAYOUT_MAXSIZE) + \
+				pagepad_maxsz)
 #define encode_layoutcommit_maxsz (op_encode_hdr_maxsz +          \
 				2 /* offset */ + \
 				2 /* length */ + \
@@ -2342,7 +2344,7 @@ static void nfs4_xdr_enc_open(struct rpc_rqst *req, struct xdr_stream *xdr,
 		encode_layoutget(xdr, args->lg_args, &hdr);
 		rpc_prepare_reply_pages(req, args->lg_args->layout.pages, 0,
 					args->lg_args->layout.pglen,
-					hdr.replen);
+					hdr.replen - pagepad_maxsz);
 	}
 	encode_nops(&hdr);
 }
@@ -2388,7 +2390,7 @@ static void nfs4_xdr_enc_open_noattr(struct rpc_rqst *req,
 		encode_layoutget(xdr, args->lg_args, &hdr);
 		rpc_prepare_reply_pages(req, args->lg_args->layout.pages, 0,
 					args->lg_args->layout.pglen,
-					hdr.replen);
+					hdr.replen - pagepad_maxsz);
 	}
 	encode_nops(&hdr);
 }
@@ -2499,7 +2501,7 @@ static void nfs4_xdr_enc_readlink(struct rpc_rqst *req, struct xdr_stream *xdr,
 	encode_readlink(xdr, args, req, &hdr);
 
 	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
-				args->pglen, hdr.replen);
+				args->pglen, hdr.replen - pagepad_maxsz);
 	encode_nops(&hdr);
 }
 
@@ -2520,7 +2522,7 @@ static void nfs4_xdr_enc_readdir(struct rpc_rqst *req, struct xdr_stream *xdr,
 	encode_readdir(xdr, args, req, &hdr);
 
 	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
-				args->count, hdr.replen);
+				args->count, hdr.replen - pagepad_maxsz);
 	encode_nops(&hdr);
 }
 
@@ -2541,7 +2543,7 @@ static void nfs4_xdr_enc_read(struct rpc_rqst *req, struct xdr_stream *xdr,
 	encode_read(xdr, args, &hdr);
 
 	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
-				args->count, hdr.replen);
+				args->count, hdr.replen - pagepad_maxsz);
 	req->rq_rcv_buf.flags |= XDRBUF_READ;
 	encode_nops(&hdr);
 }
@@ -2588,7 +2590,7 @@ static void nfs4_xdr_enc_getacl(struct rpc_rqst *req, struct xdr_stream *xdr,
 			ARRAY_SIZE(nfs4_acl_bitmap), &hdr);
 
 	rpc_prepare_reply_pages(req, args->acl_pages, 0,
-				args->acl_len, replen + 1);
+				args->acl_len, replen);
 	encode_nops(&hdr);
 }
 
@@ -2810,7 +2812,7 @@ static void nfs4_xdr_enc_fs_locations(struct rpc_rqst *req,
 	}
 
 	rpc_prepare_reply_pages(req, (struct page **)&args->page, 0,
-				PAGE_SIZE, replen + 1);
+				PAGE_SIZE, replen);
 	encode_nops(&hdr);
 }
 
@@ -3014,14 +3016,14 @@ static void nfs4_xdr_enc_getdeviceinfo(struct rpc_rqst *req,
 	encode_compound_hdr(xdr, req, &hdr);
 	encode_sequence(xdr, &args->seq_args, &hdr);
 
-	replen = hdr.replen + op_decode_hdr_maxsz;
+	replen = hdr.replen + op_decode_hdr_maxsz + 2;
 
 	encode_getdeviceinfo(xdr, args, &hdr);
 
 	/* set up reply kvec. device_addr4 opaque data is read into the
 	 * pages */
 	rpc_prepare_reply_pages(req, args->pdev->pages, args->pdev->pgbase,
-				args->pdev->pglen, replen + 2 + 1);
+				args->pdev->pglen, replen);
 	encode_nops(&hdr);
 }
 
@@ -3043,7 +3045,7 @@ static void nfs4_xdr_enc_layoutget(struct rpc_rqst *req,
 	encode_layoutget(xdr, args, &hdr);
 
 	rpc_prepare_reply_pages(req, args->layout.pages, 0,
-				args->layout.pglen, hdr.replen);
+				args->layout.pglen, hdr.replen - pagepad_maxsz);
 	encode_nops(&hdr);
 }
 
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 3259120462ed..612f0a641f4c 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -1251,10 +1251,7 @@ void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
 			     unsigned int base, unsigned int len,
 			     unsigned int hdrsize)
 {
-	/* Subtract one to force an extra word of buffer space for the
-	 * payload's XDR pad to fall into the rcv_buf's tail iovec.
-	 */
-	hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign - 1;
+	hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign;
 
 	xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
 	trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 3ce0a5daa9eb..5a450055469f 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -193,9 +193,6 @@ xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset,
 
 	tail->iov_base = buf + offset;
 	tail->iov_len = buflen - offset;
-	if ((xdr->page_len & 3) == 0)
-		tail->iov_len -= sizeof(__be32);
-
 	xdr->buflen += len;
 }
 EXPORT_SYMBOL_GPL(xdr_inline_pages);
-- 
cgit v1.2.3


From 0279024f22705128c7139bd55af6981afe90e876 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Sat, 21 Nov 2020 21:21:11 -0500
Subject: SUNRPC: Fix up xdr_set_page()

While we always want to align to the next page and/or the beginning of
the tail buffer when we call xdr_set_next_page(), the functions
xdr_align_data() and xdr_expand_hole() really want to align to the next
object in that next page or tail.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 5a450055469f..ddd5cc2281ab 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1019,8 +1019,10 @@ static unsigned int xdr_set_page_base(struct xdr_stream *xdr,
 static void xdr_set_page(struct xdr_stream *xdr, unsigned int base,
 			 unsigned int len)
 {
-	if (xdr_set_page_base(xdr, base, len) == 0)
-		xdr_set_iov(xdr, xdr->buf->tail, 0, xdr_stream_remaining(xdr));
+	if (xdr_set_page_base(xdr, base, len) == 0) {
+		base -= xdr->buf->page_len;
+		xdr_set_iov(xdr, xdr->buf->tail, base, len);
+	}
 }
 
 static void xdr_set_next_page(struct xdr_stream *xdr)
@@ -1029,17 +1031,18 @@ static void xdr_set_next_page(struct xdr_stream *xdr)
 
 	newbase = (1 + xdr->page_ptr - xdr->buf->pages) << PAGE_SHIFT;
 	newbase -= xdr->buf->page_base;
-
-	xdr_set_page(xdr, newbase, PAGE_SIZE);
+	if (newbase < xdr->buf->page_len)
+		xdr_set_page_base(xdr, newbase, xdr_stream_remaining(xdr));
+	else
+		xdr_set_iov(xdr, xdr->buf->tail, 0, xdr_stream_remaining(xdr));
 }
 
 static bool xdr_set_next_buffer(struct xdr_stream *xdr)
 {
 	if (xdr->page_ptr != NULL)
 		xdr_set_next_page(xdr);
-	else if (xdr->iov == xdr->buf->head) {
-		xdr_set_page(xdr, 0, PAGE_SIZE);
-	}
+	else if (xdr->iov == xdr->buf->head)
+		xdr_set_page(xdr, 0, xdr_stream_remaining(xdr));
 	return xdr->p != xdr->end;
 }
 
@@ -1277,7 +1280,7 @@ uint64_t xdr_align_data(struct xdr_stream *xdr, uint64_t offset, uint32_t length
 	}
 
 	xdr->nwords -= XDR_QUADLEN(length);
-	xdr_set_page(xdr, from + length, PAGE_SIZE);
+	xdr_set_page(xdr, from + length, xdr_stream_remaining(xdr));
 	return length;
 }
 EXPORT_SYMBOL_GPL(xdr_align_data);
@@ -1314,7 +1317,7 @@ uint64_t xdr_expand_hole(struct xdr_stream *xdr, uint64_t offset, uint64_t lengt
 	_zero_pages(buf->pages, buf->page_base + offset, length);
 
 	buf->len += length - (from - offset) - truncated;
-	xdr_set_page(xdr, offset + length, PAGE_SIZE);
+	xdr_set_page(xdr, offset + length, xdr_stream_remaining(xdr));
 	return length;
 }
 EXPORT_SYMBOL_GPL(xdr_expand_hole);
-- 
cgit v1.2.3


From eee1f54964fe868da425fe52a03666377335de01 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Sat, 21 Nov 2020 21:39:02 -0500
Subject: SUNRPC: Fix open coded xdr_stream_remaining()

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index ddd5cc2281ab..c852d199c789 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1261,7 +1261,7 @@ uint64_t xdr_align_data(struct xdr_stream *xdr, uint64_t offset, uint32_t length
 
 	xdr_realign_pages(xdr);
 	from = xdr_page_pos(xdr);
-	bytes = xdr->nwords << 2;
+	bytes = xdr_stream_remaining(xdr);
 	if (length < bytes)
 		bytes = length;
 
@@ -1298,7 +1298,7 @@ uint64_t xdr_expand_hole(struct xdr_stream *xdr, uint64_t offset, uint64_t lengt
 
 	xdr_realign_pages(xdr);
 	from = xdr_page_pos(xdr);
-	bytes = xdr->nwords << 2;
+	bytes = xdr_stream_remaining(xdr);
 
 	if (offset + length + bytes > buf->page_len) {
 		unsigned int shift = (offset + length + bytes) - buf->page_len;
-- 
cgit v1.2.3


From c54e959b36cbdb0cb2f2805e3e945dd83476a5c7 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Mon, 7 Dec 2020 13:30:46 -0500
Subject: SUNRPC: _shift_data_left/right_pages should check the shift length

Exit early if the shift is zero.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index c852d199c789..5833329c132c 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -225,6 +225,9 @@ _shift_data_left_pages(struct page **pages, size_t pgto_base,
 
 	BUG_ON(pgfrom_base <= pgto_base);
 
+	if (!len)
+		return;
+
 	pgto = pages + (pgto_base >> PAGE_SHIFT);
 	pgfrom = pages + (pgfrom_base >> PAGE_SHIFT);
 
@@ -307,6 +310,9 @@ _shift_data_right_pages(struct page **pages, size_t pgto_base,
 
 	BUG_ON(pgto_base <= pgfrom_base);
 
+	if (!len)
+		return;
+
 	pgto_base += len;
 	pgfrom_base += len;
 
@@ -405,6 +411,9 @@ _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len)
 	char *vto;
 	size_t copy;
 
+	if (!len)
+		return;
+
 	pgto = pages + (pgbase >> PAGE_SHIFT);
 	pgbase &= ~PAGE_MASK;
 
@@ -449,6 +458,9 @@ _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len)
 	char *vfrom;
 	size_t copy;
 
+	if (!len)
+		return;
+
 	pgfrom = pages + (pgbase >> PAGE_SHIFT);
 	pgbase &= ~PAGE_MASK;
 
-- 
cgit v1.2.3


From 9a20f6f4e6ba9713605fbf7e7426ca22f1181545 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Fri, 4 Dec 2020 15:16:46 -0500
Subject: SUNRPC: Fixes for xdr_align_data()

The main use case right now for xdr_align_data() is to shift the page
data to the left, and in practice shrink the total XDR data buffer.
This patch ensures that we fix up the accounting for the buffer length
as we shift that data around.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 include/linux/sunrpc/xdr.h |   2 +-
 net/sunrpc/xdr.c           | 174 ++++++++++++++++++++++++++++++++++-----------
 2 files changed, 133 insertions(+), 43 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 9548d075e06d..2b4e44bb0654 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -252,7 +252,7 @@ extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
-extern uint64_t xdr_align_data(struct xdr_stream *, uint64_t, uint32_t);
+extern unsigned int xdr_align_data(struct xdr_stream *, unsigned int offset, unsigned int length);
 extern uint64_t xdr_expand_hole(struct xdr_stream *, uint64_t, uint64_t);
 
 /**
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 5833329c132c..c474339ba9ac 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -266,26 +266,6 @@ _shift_data_left_pages(struct page **pages, size_t pgto_base,
 	} while ((len -= copy) != 0);
 }
 
-static void
-_shift_data_left_tail(struct xdr_buf *buf, unsigned int pgto, size_t len)
-{
-	struct kvec *tail = buf->tail;
-
-	if (len > tail->iov_len)
-		len = tail->iov_len;
-
-	_copy_to_pages(buf->pages,
-		       buf->page_base + pgto,
-		       (char *)tail->iov_base,
-		       len);
-	tail->iov_len -= len;
-
-	if (tail->iov_len > 0)
-		memmove((char *)tail->iov_base,
-				tail->iov_base + len,
-				tail->iov_len);
-}
-
 /**
  * _shift_data_right_pages
  * @pages: vector of pages containing both the source and dest memory area.
@@ -516,6 +496,109 @@ _zero_pages(struct page **pages, size_t pgbase, size_t len)
 	} while ((len -= zero) != 0);
 }
 
+static void xdr_buf_tail_copy_left(const struct xdr_buf *buf, unsigned int base,
+				   unsigned int len, unsigned int shift)
+{
+	const struct kvec *tail = buf->tail;
+
+	if (base >= tail->iov_len)
+		return;
+	if (len > tail->iov_len - base)
+		len = tail->iov_len - base;
+	/* Shift data into head */
+	if (shift > buf->page_len + base) {
+		const struct kvec *head = buf->head;
+		unsigned int hdto =
+			head->iov_len + buf->page_len + base - shift;
+		unsigned int hdlen = len;
+
+		if (WARN_ONCE(shift > head->iov_len + buf->page_len + base,
+			      "SUNRPC: Misaligned data.\n"))
+			return;
+		if (hdto + hdlen > head->iov_len)
+			hdlen = head->iov_len - hdto;
+		memcpy(head->iov_base + hdto, tail->iov_base + base, hdlen);
+		base += hdlen;
+		len -= hdlen;
+		if (!len)
+			return;
+	}
+	/* Shift data into pages */
+	if (shift > base) {
+		unsigned int pgto = buf->page_len + base - shift;
+		unsigned int pglen = len;
+
+		if (pgto + pglen > buf->page_len)
+			pglen = buf->page_len - pgto;
+		_copy_to_pages(buf->pages, buf->page_base + pgto,
+			       tail->iov_base + base, pglen);
+		base += pglen;
+		len -= pglen;
+		if (!len)
+			return;
+	}
+	memmove(tail->iov_base + base - shift, tail->iov_base + base, len);
+}
+
+static void xdr_buf_pages_copy_left(const struct xdr_buf *buf,
+				    unsigned int base, unsigned int len,
+				    unsigned int shift)
+{
+	unsigned int pgto;
+
+	if (base >= buf->page_len)
+		return;
+	if (len > buf->page_len - base)
+		len = buf->page_len - base;
+	/* Shift data into head */
+	if (shift > base) {
+		const struct kvec *head = buf->head;
+		unsigned int hdto = head->iov_len + base - shift;
+		unsigned int hdlen = len;
+
+		if (WARN_ONCE(shift > head->iov_len + base,
+			      "SUNRPC: Misaligned data.\n"))
+			return;
+		if (hdto + hdlen > head->iov_len)
+			hdlen = head->iov_len - hdto;
+		_copy_from_pages(head->iov_base + hdto, buf->pages,
+				 buf->page_base + base, hdlen);
+		base += hdlen;
+		len -= hdlen;
+		if (!len)
+			return;
+	}
+	pgto = base - shift;
+	_shift_data_left_pages(buf->pages, buf->page_base + pgto,
+			       buf->page_base + base, len);
+}
+
+static void xdr_buf_tail_shift_left(const struct xdr_buf *buf,
+				    unsigned int base, unsigned int len,
+				    unsigned int shift)
+{
+	if (!shift || !len)
+		return;
+	xdr_buf_tail_copy_left(buf, base, len, shift);
+}
+
+static void xdr_buf_pages_shift_left(const struct xdr_buf *buf,
+				     unsigned int base, unsigned int len,
+				     unsigned int shift)
+{
+	if (!shift || !len)
+		return;
+	if (base >= buf->page_len) {
+		xdr_buf_tail_shift_left(buf, base - buf->page_len, len, shift);
+		return;
+	}
+	xdr_buf_pages_copy_left(buf, base, len, shift);
+	len += base;
+	if (len <= buf->page_len)
+		return;
+	xdr_buf_tail_copy_left(buf, 0, len - buf->page_len, shift);
+}
+
 /**
  * xdr_shrink_bufhead
  * @buf: xdr_buf
@@ -1261,38 +1344,45 @@ unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
 }
 EXPORT_SYMBOL_GPL(xdr_read_pages);
 
-uint64_t xdr_align_data(struct xdr_stream *xdr, uint64_t offset, uint32_t length)
+unsigned int xdr_align_data(struct xdr_stream *xdr, unsigned int offset,
+			    unsigned int length)
 {
 	struct xdr_buf *buf = xdr->buf;
-	unsigned int from, bytes;
-	unsigned int shift = 0;
-
-	if ((offset + length) < offset ||
-	    (offset + length) > buf->page_len)
-		length = buf->page_len - offset;
+	unsigned int from, bytes, len;
+	unsigned int shift;
 
 	xdr_realign_pages(xdr);
 	from = xdr_page_pos(xdr);
-	bytes = xdr_stream_remaining(xdr);
-	if (length < bytes)
-		bytes = length;
+
+	if (from >= buf->page_len + buf->tail->iov_len)
+		return 0;
+	if (from + buf->head->iov_len >= buf->len)
+		return 0;
+
+	len = buf->len - buf->head->iov_len;
+
+	/* We only shift data left! */
+	if (WARN_ONCE(from < offset, "SUNRPC: misaligned data src=%u dst=%u\n",
+		      from, offset))
+		return 0;
+	if (WARN_ONCE(offset > buf->page_len,
+		      "SUNRPC: buffer overflow. offset=%u, page_len=%u\n",
+		      offset, buf->page_len))
+		return 0;
 
 	/* Move page data to the left */
-	if (from > offset) {
-		shift = min_t(unsigned int, bytes, buf->page_len - from);
-		_shift_data_left_pages(buf->pages,
-				       buf->page_base + offset,
-				       buf->page_base + from,
-				       shift);
-		bytes -= shift;
+	shift = from - offset;
+	xdr_buf_pages_shift_left(buf, from, len, shift);
+	xdr->buf->len -= shift;
+	xdr->nwords -= XDR_QUADLEN(shift);
 
-		/* Move tail data into the pages, if necessary */
-		if (bytes > 0)
-			_shift_data_left_tail(buf, offset + shift, bytes);
-	}
+	bytes = xdr_stream_remaining(xdr);
+	if (length > bytes)
+		length = bytes;
+	bytes -= length;
 
 	xdr->nwords -= XDR_QUADLEN(length);
-	xdr_set_page(xdr, from + length, xdr_stream_remaining(xdr));
+	xdr_set_page(xdr, offset + length, bytes);
 	return length;
 }
 EXPORT_SYMBOL_GPL(xdr_align_data);
-- 
cgit v1.2.3


From c4f2f591f02c392ea7de018d2733748bf4c7b5f5 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Fri, 4 Dec 2020 17:15:09 -0500
Subject: SUNRPC: Fix xdr_expand_hole()

We do want to try to grow the buffer if possible, but if that attempt
fails, we still want to move the data and truncate the XDR message.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 include/linux/sunrpc/xdr.h |   2 +-
 net/sunrpc/xdr.c           | 274 +++++++++++++++++++++++++++++----------------
 2 files changed, 180 insertions(+), 96 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 2b4e44bb0654..178f499e2283 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -253,7 +253,7 @@ extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
 extern unsigned int xdr_align_data(struct xdr_stream *, unsigned int offset, unsigned int length);
-extern uint64_t xdr_expand_hole(struct xdr_stream *, uint64_t, uint64_t);
+extern unsigned int xdr_expand_hole(struct xdr_stream *, unsigned int offset, unsigned int length);
 
 /**
  * xdr_stream_remaining - Return the number of bytes remaining in the stream
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index c474339ba9ac..e0906ed24374 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -334,46 +334,6 @@ _shift_data_right_pages(struct page **pages, size_t pgto_base,
 	} while ((len -= copy) != 0);
 }
 
-static unsigned int
-_shift_data_right_tail(struct xdr_buf *buf, unsigned int pgfrom, size_t len)
-{
-	struct kvec *tail = buf->tail;
-	unsigned int tailbuf_len;
-	unsigned int result = 0;
-	size_t copy;
-
-	tailbuf_len = buf->buflen - buf->head->iov_len - buf->page_len;
-
-	/* Shift the tail first */
-	if (tailbuf_len != 0) {
-		unsigned int free_space = tailbuf_len - tail->iov_len;
-
-		if (len < free_space)
-			free_space = len;
-		if (len > free_space)
-			len = free_space;
-
-		tail->iov_len += free_space;
-		copy = len;
-
-		if (tail->iov_len > len) {
-			char *p = (char *)tail->iov_base + len;
-			memmove(p, tail->iov_base, tail->iov_len - free_space);
-			result += tail->iov_len - free_space;
-		} else
-			copy = tail->iov_len;
-
-		/* Copy from the inlined pages into the tail */
-		_copy_from_pages((char *)tail->iov_base,
-					 buf->pages,
-					 buf->page_base + pgfrom,
-					 copy);
-		result += copy;
-	}
-
-	return result;
-}
-
 /**
  * _copy_to_pages
  * @pages: array of pages
@@ -464,18 +424,42 @@ _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len)
 }
 EXPORT_SYMBOL_GPL(_copy_from_pages);
 
+static void xdr_buf_iov_zero(const struct kvec *iov, unsigned int base,
+			     unsigned int len)
+{
+	if (base >= iov->iov_len)
+		return;
+	if (len > iov->iov_len - base)
+		len = iov->iov_len - base;
+	memset(iov->iov_base + base, 0, len);
+}
+
 /**
- * _zero_pages
- * @pages: array of pages
- * @pgbase: beginning page vector address
+ * xdr_buf_pages_zero
+ * @buf: xdr_buf
+ * @pgbase: beginning offset
  * @len: length
  */
-static void
-_zero_pages(struct page **pages, size_t pgbase, size_t len)
+static void xdr_buf_pages_zero(const struct xdr_buf *buf, unsigned int pgbase,
+			       unsigned int len)
 {
+	struct page **pages = buf->pages;
 	struct page **page;
 	char *vpage;
-	size_t zero;
+	unsigned int zero;
+
+	if (!len)
+		return;
+	if (pgbase >= buf->page_len) {
+		xdr_buf_iov_zero(buf->tail, pgbase - buf->page_len, len);
+		return;
+	}
+	if (pgbase + len > buf->page_len) {
+		xdr_buf_iov_zero(buf->tail, 0, pgbase + len - buf->page_len);
+		len = buf->page_len - pgbase;
+	}
+
+	pgbase += buf->page_base;
 
 	page = pages + (pgbase >> PAGE_SHIFT);
 	pgbase &= ~PAGE_MASK;
@@ -496,6 +480,103 @@ _zero_pages(struct page **pages, size_t pgbase, size_t len)
 	} while ((len -= zero) != 0);
 }
 
+static void xdr_buf_try_expand(struct xdr_buf *buf, unsigned int len)
+{
+	struct kvec *head = buf->head;
+	struct kvec *tail = buf->tail;
+	unsigned int sum = head->iov_len + buf->page_len + tail->iov_len;
+	unsigned int free_space;
+
+	if (sum > buf->len) {
+		free_space = min_t(unsigned int, sum - buf->len, len);
+		buf->len += free_space;
+		len -= free_space;
+		if (!len)
+			return;
+	}
+
+	if (buf->buflen > sum) {
+		/* Expand the tail buffer */
+		free_space = min_t(unsigned int, buf->buflen - sum, len);
+		tail->iov_len += free_space;
+		buf->len += free_space;
+	}
+}
+
+static void xdr_buf_tail_copy_right(const struct xdr_buf *buf,
+				    unsigned int base, unsigned int len,
+				    unsigned int shift)
+{
+	const struct kvec *tail = buf->tail;
+	unsigned int to = base + shift;
+
+	if (to >= tail->iov_len)
+		return;
+	if (len + to > tail->iov_len)
+		len = tail->iov_len - to;
+	memmove(tail->iov_base + to, tail->iov_base + base, len);
+}
+
+static void xdr_buf_pages_copy_right(const struct xdr_buf *buf,
+				     unsigned int base, unsigned int len,
+				     unsigned int shift)
+{
+	const struct kvec *tail = buf->tail;
+	unsigned int to = base + shift;
+	unsigned int pglen = 0;
+	unsigned int talen = 0, tato = 0;
+
+	if (base >= buf->page_len)
+		return;
+	if (len > buf->page_len - base)
+		len = buf->page_len - base;
+	if (to >= buf->page_len) {
+		tato = to - buf->page_len;
+		if (tail->iov_len >= len + tato)
+			talen = len;
+		else if (tail->iov_len > tato)
+			talen = tail->iov_len - tato;
+	} else if (len + to >= buf->page_len) {
+		pglen = buf->page_len - to;
+		talen = len - pglen;
+		if (talen > tail->iov_len)
+			talen = tail->iov_len;
+	} else
+		pglen = len;
+
+	_copy_from_pages(tail->iov_base + tato, buf->pages,
+			 buf->page_base + base + pglen, talen);
+	_shift_data_right_pages(buf->pages, buf->page_base + to,
+				buf->page_base + base, pglen);
+}
+
+static void xdr_buf_tail_shift_right(const struct xdr_buf *buf,
+				     unsigned int base, unsigned int len,
+				     unsigned int shift)
+{
+	const struct kvec *tail = buf->tail;
+
+	if (base >= tail->iov_len || !shift || !len)
+		return;
+	xdr_buf_tail_copy_right(buf, base, len, shift);
+}
+
+static void xdr_buf_pages_shift_right(const struct xdr_buf *buf,
+				      unsigned int base, unsigned int len,
+				      unsigned int shift)
+{
+	if (!shift || !len)
+		return;
+	if (base >= buf->page_len) {
+		xdr_buf_tail_shift_right(buf, base - buf->page_len, len, shift);
+		return;
+	}
+	if (base + len > buf->page_len)
+		xdr_buf_tail_shift_right(buf, 0, base + len - buf->page_len,
+					 shift);
+	xdr_buf_pages_copy_right(buf, base, len, shift);
+}
+
 static void xdr_buf_tail_copy_left(const struct xdr_buf *buf, unsigned int base,
 				   unsigned int len, unsigned int shift)
 {
@@ -685,30 +766,33 @@ xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
 }
 
 /**
- * xdr_shrink_pagelen - shrinks buf->pages by up to @len bytes
+ * xdr_shrink_pagelen - shrinks buf->pages to @len bytes
  * @buf: xdr_buf
- * @len: bytes to remove from buf->pages
+ * @len: new page buffer length
  *
  * The extra data is not lost, but is instead moved into buf->tail.
  * Returns the actual number of bytes moved.
  */
-static unsigned int
-xdr_shrink_pagelen(struct xdr_buf *buf, size_t len)
+static unsigned int xdr_shrink_pagelen(struct xdr_buf *buf, unsigned int len)
 {
-	unsigned int pglen = buf->page_len;
-	unsigned int result;
-
-	if (len > buf->page_len)
-		len = buf-> page_len;
-
-	result = _shift_data_right_tail(buf, pglen - len, len);
-	buf->page_len -= len;
-	buf->buflen -= len;
-	/* Have we truncated the message? */
-	if (buf->len > buf->buflen)
-		buf->len = buf->buflen;
+	unsigned int shift, buflen = buf->len - buf->head->iov_len;
 
-	return result;
+	WARN_ON_ONCE(len > buf->page_len);
+	if (buf->head->iov_len >= buf->len || len > buflen)
+		buflen = len;
+	if (buf->page_len > buflen) {
+		buf->buflen -= buf->page_len - buflen;
+		buf->page_len = buflen;
+	}
+	if (len >= buf->page_len)
+		return 0;
+	shift = buf->page_len - len;
+	xdr_buf_try_expand(buf, shift);
+	xdr_buf_pages_shift_right(buf, len, buflen - len, shift);
+	buf->page_len = len;
+	buf->len -= shift;
+	buf->buflen -= shift;
+	return shift;
 }
 
 void
@@ -728,6 +812,18 @@ unsigned int xdr_stream_pos(const struct xdr_stream *xdr)
 }
 EXPORT_SYMBOL_GPL(xdr_stream_pos);
 
+static void xdr_stream_set_pos(struct xdr_stream *xdr, unsigned int pos)
+{
+	unsigned int blen = xdr->buf->len;
+
+	xdr->nwords = blen > pos ? XDR_QUADLEN(blen) - XDR_QUADLEN(pos) : 0;
+}
+
+static void xdr_stream_page_set_pos(struct xdr_stream *xdr, unsigned int pos)
+{
+	xdr_stream_set_pos(xdr, pos + xdr->buf->head[0].iov_len);
+}
+
 /**
  * xdr_page_pos - Return the current offset from the start of the xdr pages
  * @xdr: pointer to struct xdr_stream
@@ -1291,7 +1387,7 @@ static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
 	struct xdr_buf *buf = xdr->buf;
 	unsigned int nwords = XDR_QUADLEN(len);
 	unsigned int cur = xdr_stream_pos(xdr);
-	unsigned int copied, offset;
+	unsigned int copied;
 
 	if (xdr->nwords == 0)
 		return 0;
@@ -1305,9 +1401,8 @@ static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
 		len = buf->page_len;
 	else if (nwords < xdr->nwords) {
 		/* Truncate page data and move it into the tail */
-		offset = buf->page_len - len;
-		copied = xdr_shrink_pagelen(buf, offset);
-		trace_rpc_xdr_alignment(xdr, offset, copied);
+		copied = xdr_shrink_pagelen(buf, len);
+		trace_rpc_xdr_alignment(xdr, len, copied);
 		xdr->nwords = XDR_QUADLEN(buf->len - cur);
 	}
 	return len;
@@ -1387,39 +1482,28 @@ unsigned int xdr_align_data(struct xdr_stream *xdr, unsigned int offset,
 }
 EXPORT_SYMBOL_GPL(xdr_align_data);
 
-uint64_t xdr_expand_hole(struct xdr_stream *xdr, uint64_t offset, uint64_t length)
+unsigned int xdr_expand_hole(struct xdr_stream *xdr, unsigned int offset,
+			     unsigned int length)
 {
 	struct xdr_buf *buf = xdr->buf;
-	unsigned int bytes;
-	unsigned int from;
-	unsigned int truncated = 0;
-
-	if ((offset + length) < offset ||
-	    (offset + length) > buf->page_len)
-		length = buf->page_len - offset;
+	unsigned int from, to, shift;
 
 	xdr_realign_pages(xdr);
 	from = xdr_page_pos(xdr);
-	bytes = xdr_stream_remaining(xdr);
-
-	if (offset + length + bytes > buf->page_len) {
-		unsigned int shift = (offset + length + bytes) - buf->page_len;
-		unsigned int res = _shift_data_right_tail(buf, from + bytes - shift, shift);
-		truncated = shift - res;
-		xdr->nwords -= XDR_QUADLEN(truncated);
-		bytes -= shift;
-	}
-
-	/* Now move the page data over and zero pages */
-	if (bytes > 0)
-		_shift_data_right_pages(buf->pages,
-					buf->page_base + offset + length,
-					buf->page_base + from,
-					bytes);
-	_zero_pages(buf->pages, buf->page_base + offset, length);
-
-	buf->len += length - (from - offset) - truncated;
-	xdr_set_page(xdr, offset + length, xdr_stream_remaining(xdr));
+	to = xdr_align_size(offset + length);
+
+	/* Could the hole be behind us? */
+	if (to > from) {
+		unsigned int buflen = buf->len - buf->head->iov_len;
+		shift = to - from;
+		xdr_buf_try_expand(buf, shift);
+		xdr_buf_pages_shift_right(buf, from, buflen, shift);
+		xdr_stream_page_set_pos(xdr, to);
+	} else if (to != from)
+		xdr_align_data(xdr, to, 0);
+	xdr_buf_pages_zero(buf, offset, length);
+
+	xdr_set_page(xdr, to, xdr_stream_remaining(xdr));
 	return length;
 }
 EXPORT_SYMBOL_GPL(xdr_expand_hole);
-- 
cgit v1.2.3


From 6707fbd7d3be72da4ebde7f56b46814befd2db19 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Sun, 6 Dec 2020 10:15:04 -0500
Subject: SUNRPC: Cleanup xdr_shrink_bufhead()

Clean up xdr_shrink_bufhead() to use the new helpers instead of doing
its own thing.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 164 +++++++++++++++++++++++++++++--------------------------
 1 file changed, 87 insertions(+), 77 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index e0906ed24374..19eaa38f7d16 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -550,6 +550,53 @@ static void xdr_buf_pages_copy_right(const struct xdr_buf *buf,
 				buf->page_base + base, pglen);
 }
 
+static void xdr_buf_head_copy_right(const struct xdr_buf *buf,
+				    unsigned int base, unsigned int len,
+				    unsigned int shift)
+{
+	const struct kvec *head = buf->head;
+	const struct kvec *tail = buf->tail;
+	unsigned int to = base + shift;
+	unsigned int pglen = 0, pgto = 0;
+	unsigned int talen = 0, tato = 0;
+
+	if (base >= head->iov_len)
+		return;
+	if (len > head->iov_len - base)
+		len = head->iov_len - base;
+	if (to >= buf->page_len + head->iov_len) {
+		tato = to - buf->page_len - head->iov_len;
+		talen = len;
+	} else if (to >= head->iov_len) {
+		pgto = to - head->iov_len;
+		pglen = len;
+		if (pgto + pglen > buf->page_len) {
+			talen = pgto + pglen - buf->page_len;
+			pglen -= talen;
+		}
+	} else {
+		pglen = len - to;
+		if (pglen > buf->page_len) {
+			talen = pglen - buf->page_len;
+			pglen = buf->page_len;
+		}
+	}
+
+	len -= talen;
+	base += len;
+	if (talen + tato > tail->iov_len)
+		talen = tail->iov_len > tato ? tail->iov_len - tato : 0;
+	memcpy(tail->iov_base + tato, head->iov_base + base, talen);
+
+	len -= pglen;
+	base -= pglen;
+	_copy_to_pages(buf->pages, buf->page_base + pgto, head->iov_base + base,
+		       pglen);
+
+	base -= len;
+	memmove(head->iov_base + to, head->iov_base + base, len);
+}
+
 static void xdr_buf_tail_shift_right(const struct xdr_buf *buf,
 				     unsigned int base, unsigned int len,
 				     unsigned int shift)
@@ -577,6 +624,25 @@ static void xdr_buf_pages_shift_right(const struct xdr_buf *buf,
 	xdr_buf_pages_copy_right(buf, base, len, shift);
 }
 
+static void xdr_buf_head_shift_right(const struct xdr_buf *buf,
+				     unsigned int base, unsigned int len,
+				     unsigned int shift)
+{
+	const struct kvec *head = buf->head;
+
+	if (!shift)
+		return;
+	if (base >= head->iov_len) {
+		xdr_buf_pages_shift_right(buf, head->iov_len - base, len,
+					  shift);
+		return;
+	}
+	if (base + len > head->iov_len)
+		xdr_buf_pages_shift_right(buf, 0, base + len - head->iov_len,
+					  shift);
+	xdr_buf_head_copy_right(buf, base, len, shift);
+}
+
 static void xdr_buf_tail_copy_left(const struct xdr_buf *buf, unsigned int base,
 				   unsigned int len, unsigned int shift)
 {
@@ -683,86 +749,31 @@ static void xdr_buf_pages_shift_left(const struct xdr_buf *buf,
 /**
  * xdr_shrink_bufhead
  * @buf: xdr_buf
- * @len: bytes to remove from buf->head[0]
+ * @len: new length of buf->head[0]
  *
- * Shrinks XDR buffer's header kvec buf->head[0] by
+ * Shrinks XDR buffer's header kvec buf->head[0], setting it to
  * 'len' bytes. The extra data is not lost, but is instead
  * moved into the inlined pages and/or the tail.
  */
-static unsigned int
-xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
+static unsigned int xdr_shrink_bufhead(struct xdr_buf *buf, unsigned int len)
 {
-	struct kvec *head, *tail;
-	size_t copy, offs;
-	unsigned int pglen = buf->page_len;
-	unsigned int result;
-
-	result = 0;
-	tail = buf->tail;
-	head = buf->head;
+	struct kvec *head = buf->head;
+	unsigned int shift, buflen = max(buf->len, len);
 
 	WARN_ON_ONCE(len > head->iov_len);
-	if (len > head->iov_len)
-		len = head->iov_len;
-
-	/* Shift the tail first */
-	if (tail->iov_len != 0) {
-		if (tail->iov_len > len) {
-			copy = tail->iov_len - len;
-			memmove((char *)tail->iov_base + len,
-					tail->iov_base, copy);
-			result += copy;
-		}
-		/* Copy from the inlined pages into the tail */
-		copy = len;
-		if (copy > pglen)
-			copy = pglen;
-		offs = len - copy;
-		if (offs >= tail->iov_len)
-			copy = 0;
-		else if (copy > tail->iov_len - offs)
-			copy = tail->iov_len - offs;
-		if (copy != 0) {
-			_copy_from_pages((char *)tail->iov_base + offs,
-					buf->pages,
-					buf->page_base + pglen + offs - len,
-					copy);
-			result += copy;
-		}
-		/* Do we also need to copy data from the head into the tail ? */
-		if (len > pglen) {
-			offs = copy = len - pglen;
-			if (copy > tail->iov_len)
-				copy = tail->iov_len;
-			memcpy(tail->iov_base,
-					(char *)head->iov_base +
-					head->iov_len - offs,
-					copy);
-			result += copy;
-		}
+	if (head->iov_len > buflen) {
+		buf->buflen -= head->iov_len - buflen;
+		head->iov_len = buflen;
 	}
-	/* Now handle pages */
-	if (pglen != 0) {
-		if (pglen > len)
-			_shift_data_right_pages(buf->pages,
-					buf->page_base + len,
-					buf->page_base,
-					pglen - len);
-		copy = len;
-		if (len > pglen)
-			copy = pglen;
-		_copy_to_pages(buf->pages, buf->page_base,
-				(char *)head->iov_base + head->iov_len - len,
-				copy);
-		result += copy;
-	}
-	head->iov_len -= len;
-	buf->buflen -= len;
-	/* Have we truncated the message? */
-	if (buf->len > buf->buflen)
-		buf->len = buf->buflen;
-
-	return result;
+	if (len >= head->iov_len)
+		return 0;
+	shift = head->iov_len - len;
+	xdr_buf_try_expand(buf, shift);
+	xdr_buf_head_shift_right(buf, len, buflen - len, shift);
+	head->iov_len = len;
+	buf->buflen -= shift;
+	buf->len -= shift;
+	return shift;
 }
 
 /**
@@ -798,7 +809,7 @@ static unsigned int xdr_shrink_pagelen(struct xdr_buf *buf, unsigned int len)
 void
 xdr_shift_buf(struct xdr_buf *buf, size_t len)
 {
-	xdr_shrink_bufhead(buf, len);
+	xdr_shrink_bufhead(buf, buf->head->iov_len - len);
 }
 EXPORT_SYMBOL_GPL(xdr_shift_buf);
 
@@ -1371,13 +1382,12 @@ static void xdr_realign_pages(struct xdr_stream *xdr)
 	struct xdr_buf *buf = xdr->buf;
 	struct kvec *iov = buf->head;
 	unsigned int cur = xdr_stream_pos(xdr);
-	unsigned int copied, offset;
+	unsigned int copied;
 
 	/* Realign pages to current pointer position */
 	if (iov->iov_len > cur) {
-		offset = iov->iov_len - cur;
-		copied = xdr_shrink_bufhead(buf, offset);
-		trace_rpc_xdr_alignment(xdr, offset, copied);
+		copied = xdr_shrink_bufhead(buf, cur);
+		trace_rpc_xdr_alignment(xdr, cur, copied);
 		xdr->nwords = XDR_QUADLEN(buf->len - cur);
 	}
 }
-- 
cgit v1.2.3


From e43ac22b83921928479da0bad25aaee3d95c2b1a Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Sun, 6 Dec 2020 12:41:41 -0500
Subject: SUNRPC: _copy_to/from_pages() now check for zero length

Clean up callers of _copy_to/from_pages() that still check for a zero
length.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 19eaa38f7d16..01918e60b67b 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1665,8 +1665,7 @@ static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigne
 	len -= this_len;
 	obj += this_len;
 	this_len = min_t(unsigned int, len, subbuf->page_len);
-	if (this_len)
-		_copy_from_pages(obj, subbuf->pages, subbuf->page_base, this_len);
+	_copy_from_pages(obj, subbuf->pages, subbuf->page_base, this_len);
 	len -= this_len;
 	obj += this_len;
 	this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len);
@@ -1696,8 +1695,7 @@ static void __write_bytes_to_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned
 	len -= this_len;
 	obj += this_len;
 	this_len = min_t(unsigned int, len, subbuf->page_len);
-	if (this_len)
-		_copy_to_pages(subbuf->pages, subbuf->page_base, obj, this_len);
+	_copy_to_pages(subbuf->pages, subbuf->page_base, obj, this_len);
 	len -= this_len;
 	obj += this_len;
 	this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len);
-- 
cgit v1.2.3


From 5a5f1c2c2cbb6ddef637abb7c7e7cab20b9cc933 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Tue, 8 Dec 2020 15:02:14 -0500
Subject: SUNRPC: Clean up open coded setting of the xdr_stream 'nwords' field

Move the setting of the xdr_stream 'nwords' field into the helpers that
reset the xdr_stream cursor.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 29 ++++++++++++++++-------------
 1 file changed, 16 insertions(+), 13 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 01918e60b67b..f0444bf5617c 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1183,6 +1183,15 @@ static unsigned int xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov,
 	return len - base;
 }
 
+static unsigned int xdr_set_tail_base(struct xdr_stream *xdr,
+				      unsigned int base, unsigned int len)
+{
+	struct xdr_buf *buf = xdr->buf;
+
+	xdr_stream_set_pos(xdr, base + buf->page_len + buf->head->iov_len);
+	return xdr_set_iov(xdr, buf->tail, base, len);
+}
+
 static unsigned int xdr_set_page_base(struct xdr_stream *xdr,
 				      unsigned int base, unsigned int len)
 {
@@ -1201,6 +1210,7 @@ static unsigned int xdr_set_page_base(struct xdr_stream *xdr,
 	if (len > maxlen)
 		len = maxlen;
 
+	xdr_stream_page_set_pos(xdr, base);
 	base += xdr->buf->page_base;
 
 	pgnr = base >> PAGE_SHIFT;
@@ -1223,7 +1233,7 @@ static void xdr_set_page(struct xdr_stream *xdr, unsigned int base,
 {
 	if (xdr_set_page_base(xdr, base, len) == 0) {
 		base -= xdr->buf->page_len;
-		xdr_set_iov(xdr, xdr->buf->tail, base, len);
+		xdr_set_tail_base(xdr, base, len);
 	}
 }
 
@@ -1236,7 +1246,7 @@ static void xdr_set_next_page(struct xdr_stream *xdr)
 	if (newbase < xdr->buf->page_len)
 		xdr_set_page_base(xdr, newbase, xdr_stream_remaining(xdr));
 	else
-		xdr_set_iov(xdr, xdr->buf->tail, 0, xdr_stream_remaining(xdr));
+		xdr_set_tail_base(xdr, 0, xdr_stream_remaining(xdr));
 }
 
 static bool xdr_set_next_buffer(struct xdr_stream *xdr)
@@ -1388,7 +1398,7 @@ static void xdr_realign_pages(struct xdr_stream *xdr)
 	if (iov->iov_len > cur) {
 		copied = xdr_shrink_bufhead(buf, cur);
 		trace_rpc_xdr_alignment(xdr, cur, copied);
-		xdr->nwords = XDR_QUADLEN(buf->len - cur);
+		xdr_set_page(xdr, 0, buf->page_len);
 	}
 }
 
@@ -1396,7 +1406,6 @@ static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
 {
 	struct xdr_buf *buf = xdr->buf;
 	unsigned int nwords = XDR_QUADLEN(len);
-	unsigned int cur = xdr_stream_pos(xdr);
 	unsigned int copied;
 
 	if (xdr->nwords == 0)
@@ -1413,7 +1422,6 @@ static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
 		/* Truncate page data and move it into the tail */
 		copied = xdr_shrink_pagelen(buf, len);
 		trace_rpc_xdr_alignment(xdr, len, copied);
-		xdr->nwords = XDR_QUADLEN(buf->len - cur);
 	}
 	return len;
 }
@@ -1439,12 +1447,10 @@ unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
 	if (pglen == 0)
 		return 0;
 
-	xdr->nwords -= nwords;
 	base = (nwords << 2) - pglen;
 	end = xdr_stream_remaining(xdr) - pglen;
 
-	if (xdr_set_iov(xdr, xdr->buf->tail, base, end) == 0)
-		xdr->nwords = 0;
+	xdr_set_tail_base(xdr, base, end);
 	return len <= pglen ? len : pglen;
 }
 EXPORT_SYMBOL_GPL(xdr_read_pages);
@@ -1478,15 +1484,13 @@ unsigned int xdr_align_data(struct xdr_stream *xdr, unsigned int offset,
 	/* Move page data to the left */
 	shift = from - offset;
 	xdr_buf_pages_shift_left(buf, from, len, shift);
-	xdr->buf->len -= shift;
-	xdr->nwords -= XDR_QUADLEN(shift);
 
 	bytes = xdr_stream_remaining(xdr);
 	if (length > bytes)
 		length = bytes;
 	bytes -= length;
 
-	xdr->nwords -= XDR_QUADLEN(length);
+	xdr->buf->len -= shift;
 	xdr_set_page(xdr, offset + length, bytes);
 	return length;
 }
@@ -1508,12 +1512,11 @@ unsigned int xdr_expand_hole(struct xdr_stream *xdr, unsigned int offset,
 		shift = to - from;
 		xdr_buf_try_expand(buf, shift);
 		xdr_buf_pages_shift_right(buf, from, buflen, shift);
-		xdr_stream_page_set_pos(xdr, to);
+		xdr_set_page(xdr, to, xdr_stream_remaining(xdr));
 	} else if (to != from)
 		xdr_align_data(xdr, to, 0);
 	xdr_buf_pages_zero(buf, offset, length);
 
-	xdr_set_page(xdr, to, xdr_stream_remaining(xdr));
 	return length;
 }
 EXPORT_SYMBOL_GPL(xdr_expand_hole);
-- 
cgit v1.2.3


From f8d0e60f1056687826abc1eded98f0ea067dfc4c Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Tue, 8 Dec 2020 22:56:18 -0500
Subject: SUNRPC: Cleanup - constify a number of xdr_buf helpers

There are a number of xdr helpers for struct xdr_buf that do not change
the structure itself. Mark those as taking const pointers for
documentation purposes.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 include/linux/sunrpc/xdr.h | 22 +++++++++----------
 net/sunrpc/xdr.c           | 53 +++++++++++++++++++++-------------------------
 2 files changed, 35 insertions(+), 40 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 178f499e2283..68d49fdc4ee9 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -128,8 +128,8 @@ __be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
 
 void	xdr_inline_pages(struct xdr_buf *, unsigned int,
 			 struct page **, unsigned int, unsigned int);
-void	xdr_terminate_string(struct xdr_buf *, const u32);
-size_t	xdr_buf_pagecount(struct xdr_buf *buf);
+void	xdr_terminate_string(const struct xdr_buf *, const u32);
+size_t	xdr_buf_pagecount(const struct xdr_buf *buf);
 int	xdr_alloc_bvec(struct xdr_buf *buf, gfp_t gfp);
 void	xdr_free_bvec(struct xdr_buf *buf);
 
@@ -182,14 +182,14 @@ xdr_adjust_iovec(struct kvec *iov, __be32 *p)
  * XDR buffer helper functions
  */
 extern void xdr_shift_buf(struct xdr_buf *, size_t);
-extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
-extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
+extern void xdr_buf_from_iov(const struct kvec *, struct xdr_buf *);
+extern int xdr_buf_subsegment(const struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
 extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
-extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
-extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
+extern int read_bytes_from_xdr_buf(const struct xdr_buf *, unsigned int, void *, unsigned int);
+extern int write_bytes_to_xdr_buf(const struct xdr_buf *, unsigned int, void *, unsigned int);
 
-extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
-extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
+extern int xdr_encode_word(const struct xdr_buf *, unsigned int, u32);
+extern int xdr_decode_word(const struct xdr_buf *, unsigned int, u32 *);
 
 struct xdr_array2_desc;
 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
@@ -200,9 +200,9 @@ struct xdr_array2_desc {
 	xdr_xcode_elem_t xcode;
 };
 
-extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
+extern int xdr_decode_array2(const struct xdr_buf *buf, unsigned int base,
 			     struct xdr_array2_desc *desc);
-extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
+extern int xdr_encode_array2(const struct xdr_buf *buf, unsigned int base,
 			     struct xdr_array2_desc *desc);
 extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase,
 			     size_t len);
@@ -251,7 +251,7 @@ extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buf
 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
-extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
+extern int xdr_process_buf(const struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
 extern unsigned int xdr_align_data(struct xdr_stream *, unsigned int offset, unsigned int length);
 extern unsigned int xdr_expand_hole(struct xdr_stream *, unsigned int offset, unsigned int length);
 
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index f0444bf5617c..2e91fbd70f11 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -123,8 +123,7 @@ EXPORT_SYMBOL_GPL(xdr_decode_string_inplace);
  * @len: length of string, in bytes
  *
  */
-void
-xdr_terminate_string(struct xdr_buf *buf, const u32 len)
+void xdr_terminate_string(const struct xdr_buf *buf, const u32 len)
 {
 	char *kaddr;
 
@@ -134,8 +133,7 @@ xdr_terminate_string(struct xdr_buf *buf, const u32 len)
 }
 EXPORT_SYMBOL_GPL(xdr_terminate_string);
 
-size_t
-xdr_buf_pagecount(struct xdr_buf *buf)
+size_t xdr_buf_pagecount(const struct xdr_buf *buf)
 {
 	if (!buf->page_len)
 		return 0;
@@ -1545,8 +1543,7 @@ EXPORT_SYMBOL_GPL(xdr_enter_page);
 
 static const struct kvec empty_iov = {.iov_base = NULL, .iov_len = 0};
 
-void
-xdr_buf_from_iov(struct kvec *iov, struct xdr_buf *buf)
+void xdr_buf_from_iov(const struct kvec *iov, struct xdr_buf *buf)
 {
 	buf->head[0] = *iov;
 	buf->tail[0] = empty_iov;
@@ -1569,9 +1566,8 @@ EXPORT_SYMBOL_GPL(xdr_buf_from_iov);
  *
  * Returns -1 if base of length are out of bounds.
  */
-int
-xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf,
-			unsigned int base, unsigned int len)
+int xdr_buf_subsegment(const struct xdr_buf *buf, struct xdr_buf *subbuf,
+		       unsigned int base, unsigned int len)
 {
 	subbuf->buflen = subbuf->len = len;
 	if (base < buf->head[0].iov_len) {
@@ -1659,7 +1655,8 @@ fix_len:
 }
 EXPORT_SYMBOL_GPL(xdr_buf_trim);
 
-static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
+static void __read_bytes_from_xdr_buf(const struct xdr_buf *subbuf,
+				      void *obj, unsigned int len)
 {
 	unsigned int this_len;
 
@@ -1676,7 +1673,8 @@ static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigne
 }
 
 /* obj is assumed to point to allocated memory of size at least len: */
-int read_bytes_from_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len)
+int read_bytes_from_xdr_buf(const struct xdr_buf *buf, unsigned int base,
+			    void *obj, unsigned int len)
 {
 	struct xdr_buf subbuf;
 	int status;
@@ -1689,7 +1687,8 @@ int read_bytes_from_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, u
 }
 EXPORT_SYMBOL_GPL(read_bytes_from_xdr_buf);
 
-static void __write_bytes_to_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
+static void __write_bytes_to_xdr_buf(const struct xdr_buf *subbuf,
+				     void *obj, unsigned int len)
 {
 	unsigned int this_len;
 
@@ -1706,7 +1705,8 @@ static void __write_bytes_to_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned
 }
 
 /* obj is assumed to point to allocated memory of size at least len: */
-int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len)
+int write_bytes_to_xdr_buf(const struct xdr_buf *buf, unsigned int base,
+			   void *obj, unsigned int len)
 {
 	struct xdr_buf subbuf;
 	int status;
@@ -1719,8 +1719,7 @@ int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, un
 }
 EXPORT_SYMBOL_GPL(write_bytes_to_xdr_buf);
 
-int
-xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj)
+int xdr_decode_word(const struct xdr_buf *buf, unsigned int base, u32 *obj)
 {
 	__be32	raw;
 	int	status;
@@ -1733,8 +1732,7 @@ xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj)
 }
 EXPORT_SYMBOL_GPL(xdr_decode_word);
 
-int
-xdr_encode_word(struct xdr_buf *buf, unsigned int base, u32 obj)
+int xdr_encode_word(const struct xdr_buf *buf, unsigned int base, u32 obj)
 {
 	__be32	raw = cpu_to_be32(obj);
 
@@ -1743,9 +1741,8 @@ xdr_encode_word(struct xdr_buf *buf, unsigned int base, u32 obj)
 EXPORT_SYMBOL_GPL(xdr_encode_word);
 
 /* Returns 0 on success, or else a negative error code. */
-static int
-xdr_xcode_array2(struct xdr_buf *buf, unsigned int base,
-		 struct xdr_array2_desc *desc, int encode)
+static int xdr_xcode_array2(const struct xdr_buf *buf, unsigned int base,
+			    struct xdr_array2_desc *desc, int encode)
 {
 	char *elem = NULL, *c;
 	unsigned int copied = 0, todo, avail_here;
@@ -1937,9 +1934,8 @@ out:
 	return err;
 }
 
-int
-xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
-		  struct xdr_array2_desc *desc)
+int xdr_decode_array2(const struct xdr_buf *buf, unsigned int base,
+		      struct xdr_array2_desc *desc)
 {
 	if (base >= buf->len)
 		return -EINVAL;
@@ -1948,9 +1944,8 @@ xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 }
 EXPORT_SYMBOL_GPL(xdr_decode_array2);
 
-int
-xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
-		  struct xdr_array2_desc *desc)
+int xdr_encode_array2(const struct xdr_buf *buf, unsigned int base,
+		      struct xdr_array2_desc *desc)
 {
 	if ((unsigned long) base + 4 + desc->array_len * desc->elem_size >
 	    buf->head->iov_len + buf->page_len + buf->tail->iov_len)
@@ -1960,9 +1955,9 @@ xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
 }
 EXPORT_SYMBOL_GPL(xdr_encode_array2);
 
-int
-xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len,
-		int (*actor)(struct scatterlist *, void *), void *data)
+int xdr_process_buf(const struct xdr_buf *buf, unsigned int offset,
+		    unsigned int len,
+		    int (*actor)(struct scatterlist *, void *), void *data)
 {
 	int i, ret = 0;
 	unsigned int page_len, thislen, page_offset;
-- 
cgit v1.2.3


From 5802f7c2a6b876b2810e3e9f26d719961f12e251 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Thu, 10 Dec 2020 08:55:35 -0500
Subject: SUNRPC: When expanding the buffer, we may need grow the sparse pages

If we're shifting the page data to the right, and this happens to be a
sparse page array, then we may need to allocate new pages in order to
receive the data.

Reported-by: "Mkrtchyan, Tigran" <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/xdr.c | 35 +++++++++++++++++++++++++++++++++--
 1 file changed, 33 insertions(+), 2 deletions(-)

(limited to 'net/sunrpc/xdr.c')

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 2e91fbd70f11..60d4442c5273 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -478,16 +478,47 @@ static void xdr_buf_pages_zero(const struct xdr_buf *buf, unsigned int pgbase,
 	} while ((len -= zero) != 0);
 }
 
+static unsigned int xdr_buf_pages_fill_sparse(const struct xdr_buf *buf,
+					      unsigned int buflen, gfp_t gfp)
+{
+	unsigned int i, npages, pagelen;
+
+	if (!(buf->flags & XDRBUF_SPARSE_PAGES))
+		return buflen;
+	if (buflen <= buf->head->iov_len)
+		return buflen;
+	pagelen = buflen - buf->head->iov_len;
+	if (pagelen > buf->page_len)
+		pagelen = buf->page_len;
+	npages = (pagelen + buf->page_base + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	for (i = 0; i < npages; i++) {
+		if (!buf->pages[i])
+			continue;
+		buf->pages[i] = alloc_page(gfp);
+		if (likely(buf->pages[i]))
+			continue;
+		buflen -= pagelen;
+		pagelen = i << PAGE_SHIFT;
+		if (pagelen > buf->page_base)
+			buflen += pagelen - buf->page_base;
+		break;
+	}
+	return buflen;
+}
+
 static void xdr_buf_try_expand(struct xdr_buf *buf, unsigned int len)
 {
 	struct kvec *head = buf->head;
 	struct kvec *tail = buf->tail;
 	unsigned int sum = head->iov_len + buf->page_len + tail->iov_len;
-	unsigned int free_space;
+	unsigned int free_space, newlen;
 
 	if (sum > buf->len) {
 		free_space = min_t(unsigned int, sum - buf->len, len);
-		buf->len += free_space;
+		newlen = xdr_buf_pages_fill_sparse(buf, buf->len + free_space,
+						   GFP_KERNEL);
+		free_space = newlen - buf->len;
+		buf->len = newlen;
 		len -= free_space;
 		if (!len)
 			return;
-- 
cgit v1.2.3