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* [PATCH 0/7] NFS: Add support for the v4.2 READ_PLUS operation
@ 2020-01-10 22:34 schumaker.anna
  2020-01-10 22:34 ` [PATCH 1/7] SUNRPC: Split out a function for setting current page schumaker.anna
                   ` (6 more replies)
  0 siblings, 7 replies; 11+ messages in thread
From: schumaker.anna @ 2020-01-10 22:34 UTC (permalink / raw)
  To: Trond.Myklebust, linux-nfs; +Cc: Anna.Schumaker

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

These patches add client support for the READ_PLUS operation, which
breaks read requests into several "data" and "hole" segments when
replying to the client. I also add a "noreadplus" mount option to allow
users to disable the new operation if it becomes a problem, similar to
the "nordirplus" mount option that we already have.

Here are the results of some performance tests I ran on Netapp lab
machines. I tested by reading various 2G files from a few different
undelying filesystems and across several NFS versions. I used the
`vmtouch` utility to make sure files were only cached when we wanted
them to be. In addition to 100% data and 100% hole cases, I also tested
with files that alternate between data and hole segments. These files
have either 4K, 8K, 16K, or 32K segment sizes and start with either data
or hole segments. So the file mixed-4d has a 4K segment size beginning
with a data segment, but mixed-32h hase 32K segments beginning with a
hole. The units are in seconds, with the first number for each NFS
version being the uncached read time and the second number is for when
the file is cached on the server.

ext4      |        v3       |       v4.0      |       v4.1      |       v4.2      |
----------|-----------------|-----------------|-----------------|-----------------|
data      | 22.909 : 18.253 | 22.934 : 18.252 | 22.902 : 18.253 | 23.485 : 18.253 |
hole      | 18.256 : 18.253 | 18.255 : 18.252 | 18.256 : 18.253 |  0.708 :  0.709 |
mixed-4d  | 28.261 : 18.253 | 29.616 : 18.252 | 28.341 : 18.252 | 24.508 :  9.150 |
mixed-8d  | 27.956 : 18.253 | 28.404 : 18.252 | 28.320 : 18.252 | 23.967 :  9.140 |
mixed-16d | 28.172 : 18.253 | 27.946 : 18.252 | 27.627 : 18.252 | 23.043 :  9.134 |
mixed-32d | 25.350 : 18.253 | 24.406 : 18.252 | 24.384 : 18.253 | 20.698 :  9.132 |
mixed-4h  | 28.913 : 18.253 | 28.564 : 18.252 | 27.996 : 18.252 | 21.837 :  9.150 |
mixed-8h  | 28.625 : 18.253 | 27.833 : 18.252 | 27.798 : 18.253 | 21.710 :  9.140 |
mixed-16h | 27.975 : 18.253 | 27.662 : 18.252 | 27.795 : 18.253 | 20.585 :  9.134 |
mixed-32h | 25.958 : 18.253 | 25.491 : 18.252 | 24.856 : 18.252 | 21.018 :  9.132 |

xfs       |        v3       |       v4.0      |       v4.1      |       v4.2      |
----------|-----------------|-----------------|-----------------|-----------------|
data      | 22.041 : 18.253 | 22.618 : 18.252 | 23.067 : 18.253 | 23.496 : 18.253 |
hole      | 18.256 : 18.253 | 18.255 : 18.252 | 18.256 : 18.253 |  0.723 :  0.708 |
mixed-4d  | 29.417 : 18.253 | 28.503 : 18.252 | 28.671 : 18.253 | 24.957 :  9.150 |
mixed-8d  | 29.080 : 18.253 | 29.401 : 18.252 | 29.251 : 18.252 | 24.625 :  9.140 |
mixed-16d | 27.638 : 18.253 | 28.606 : 18.252 | 27.871 : 18.253 | 25.511 :  9.135 |
mixed-32d | 24.967 : 18.253 | 25.239 : 18.252 | 25.434 : 18.252 | 21.728 :  9.132 |
mixed-4h  | 34.816 : 18.253 | 36.243 : 18.252 | 35.837 : 18.252 | 32.332 :  9.150 |
mixed-8h  | 43.469 : 18.253 | 44.009 : 18.252 | 43.810 : 18.253 | 37.962 :  9.140 |
mixed-16h | 29.280 : 18.253 | 28.563 : 18.252 | 28.241 : 18.252 | 22.116 :  9.134 |
mixed-32h | 29.428 : 18.253 | 29.378 : 18.252 | 28.808 : 18.253 | 27.378 :  9.134 |

btrfs     |        v3       |       v4.0      |       v4.1      |       v4.2      |
----------|-----------------|-----------------|-----------------|-----------------|
data      | 25.547 : 18.253 | 25.053 : 18.252 | 24.209 : 18.253 | 32.121 : 18.253 |
hole      | 18.256 : 18.253 | 18.255 : 18.252 | 18.256 : 18.252 |  0.702 :  0.724 |
mixed-4d  | 19.016 : 18.253 | 18.822 : 18.252 | 18.955 : 18.253 | 18.697 :  9.150 |
mixed-8d  | 19.186 : 18.253 | 19.444 : 18.252 | 18.841 : 18.253 | 18.452 :  9.140 |
mixed-16d | 18.480 : 18.253 | 19.010 : 18.252 | 19.167 : 18.252 | 16.000 :  9.134 |
mixed-32d | 18.635 : 18.253 | 18.565 : 18.252 | 18.550 : 18.252 | 15.930 :  9.132 |
mixed-4h  | 19.079 : 18.253 | 18.990 : 18.252 | 19.157 : 18.253 | 27.834 :  9.150 |
mixed-8h  | 18.613 : 18.253 | 19.234 : 18.252 | 18.616 : 18.253 | 20.177 :  9.140 |
mixed-16h | 18.590 : 18.253 | 19.221 : 18.252 | 19.654 : 18.253 | 17.273 :  9.135 |
mixed-32h | 18.768 : 18.253 | 19.122 : 18.252 | 18.535 : 18.252 | 15.791 :  9.132 |

ext3      |        v3       |       v4.0      |       v4.1      |       v4.2      |
----------|-----------------|-----------------|-----------------|-----------------|
data      | 34.292 : 18.253 | 33.810 : 18.252 | 33.450 : 18.253 | 33.390 : 18.254 |
hole      | 18.256 : 18.253 | 18.255 : 18.252 | 18.256 : 18.253 |  0.718 :  0.728 |
mixed-4d  | 46.818 : 18.253 | 47.140 : 18.252 | 48.385 : 18.253 | 42.887 :  9.150 |
mixed-8d  | 58.554 : 18.253 | 59.277 : 18.252 | 59.673 : 18.253 | 56.760 :  9.140 |
mixed-16d | 44.631 : 18.253 | 44.291 : 18.252 | 44.729 : 18.253 | 40.237 :  9.135 |
mixed-32d | 39.110 : 18.253 | 38.735 : 18.252 | 38.902 : 18.252 | 35.270 :  9.132 |
mixed-4h  | 56.396 : 18.253 | 56.387 : 18.252 | 56.573 : 18.253 | 67.661 :  9.150 |
mixed-8h  | 58.483 : 18.253 | 58.484 : 18.252 | 59.099 : 18.253 | 77.958 :  9.140 |
mixed-16h | 42.511 : 18.253 | 42.338 : 18.252 | 42.356 : 18.252 | 51.805 :  9.135 |
mixed-32h | 38.419 : 18.253 | 38.504 : 18.252 | 38.643 : 18.252 | 40.411 :  9.132 |

Any questions?
Anna

Anna Schumaker (7):
  SUNRPC: Split out a function for setting current page
  SUNRPC: Add the ability to expand holes in data pages
  SUNRPC: Add the ability to shift data to a specific offset
  NFS: Add READ_PLUS data segment support
  NFS: Add READ_PLUS hole segment decoding
  NFS: Decode multiple READ_PLUS segments
  NFS: Add a mount option for READ_PLUS

 fs/nfs/fs_context.c        |  14 +++
 fs/nfs/nfs42xdr.c          | 169 +++++++++++++++++++++++++
 fs/nfs/nfs4client.c        |   3 +
 fs/nfs/nfs4proc.c          |  32 ++++-
 fs/nfs/nfs4xdr.c           |   1 +
 include/linux/nfs4.h       |   2 +-
 include/linux/nfs_fs_sb.h  |   2 +
 include/linux/nfs_xdr.h    |   2 +-
 include/linux/sunrpc/xdr.h |   2 +
 net/sunrpc/xdr.c           | 244 ++++++++++++++++++++++++++++++++++++-
 10 files changed, 464 insertions(+), 7 deletions(-)

-- 
2.24.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* [PATCH 1/7] SUNRPC: Split out a function for setting current page
  2020-01-10 22:34 [PATCH 0/7] NFS: Add support for the v4.2 READ_PLUS operation schumaker.anna
@ 2020-01-10 22:34 ` schumaker.anna
  2020-01-10 22:34 ` [PATCH 2/7] SUNRPC: Add the ability to expand holes in data pages schumaker.anna
                   ` (5 subsequent siblings)
  6 siblings, 0 replies; 11+ messages in thread
From: schumaker.anna @ 2020-01-10 22:34 UTC (permalink / raw)
  To: Trond.Myklebust, linux-nfs; +Cc: Anna.Schumaker

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

I'm going to need this bit of code in a few places for READ_PLUS
decoding, so let's make it a helper function.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
 net/sunrpc/xdr.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index e5497dc2475b..8bed0ec21563 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -825,6 +825,12 @@ static int xdr_set_page_base(struct xdr_stream *xdr,
 	return 0;
 }
 
+static void xdr_set_page(struct xdr_stream *xdr, unsigned int base)
+{
+	if (xdr_set_page_base(xdr, base, PAGE_SIZE) < 0)
+		xdr_set_iov(xdr, xdr->buf->tail, xdr->nwords << 2);
+}
+
 static void xdr_set_next_page(struct xdr_stream *xdr)
 {
 	unsigned int newbase;
@@ -832,8 +838,7 @@ 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;
 
-	if (xdr_set_page_base(xdr, newbase, PAGE_SIZE) < 0)
-		xdr_set_iov(xdr, xdr->buf->tail, xdr->nwords << 2);
+	xdr_set_page(xdr, newbase);
 }
 
 static bool xdr_set_next_buffer(struct xdr_stream *xdr)
-- 
2.24.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* [PATCH 2/7] SUNRPC: Add the ability to expand holes in data pages
  2020-01-10 22:34 [PATCH 0/7] NFS: Add support for the v4.2 READ_PLUS operation schumaker.anna
  2020-01-10 22:34 ` [PATCH 1/7] SUNRPC: Split out a function for setting current page schumaker.anna
@ 2020-01-10 22:34 ` schumaker.anna
  2020-01-10 22:34 ` [PATCH 3/7] SUNRPC: Add the ability to shift data to a specific offset schumaker.anna
                   ` (4 subsequent siblings)
  6 siblings, 0 replies; 11+ messages in thread
From: schumaker.anna @ 2020-01-10 22:34 UTC (permalink / raw)
  To: Trond.Myklebust, linux-nfs; +Cc: Anna.Schumaker

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

This patch adds the ability to "read a hole" into a set of XDR data
pages by taking the following steps:

1) Shift all data after the current xdr->p to the right, possibly into
   the tail,
2) Zero the specified range, and
3) Update xdr->p to point beyond the hole.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
 include/linux/sunrpc/xdr.h |   1 +
 net/sunrpc/xdr.c           | 100 +++++++++++++++++++++++++++++++++++++
 2 files changed, 101 insertions(+)

diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index b41f34977995..81a79099ed3b 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -263,6 +263,7 @@ 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 size_t xdr_expand_hole(struct xdr_stream *, size_t, uint64_t);
 
 /**
  * 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 8bed0ec21563..bc9b9b0945f5 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -266,6 +266,40 @@ _shift_data_right_pages(struct page **pages, size_t pgto_base,
 	} while ((len -= copy) != 0);
 }
 
+static void
+_shift_data_right_tail(struct xdr_buf *buf, size_t pgfrom_base, size_t len)
+{
+	struct kvec *tail = buf->tail;
+
+	/* Make room for new data. */
+	if (tail->iov_len > 0)
+		memmove((char *)tail->iov_base + len, tail->iov_base, len);
+
+	_copy_from_pages((char *)tail->iov_base,
+			 buf->pages,
+			 buf->page_base + pgfrom_base,
+			 len);
+
+	tail->iov_len += len;
+}
+
+static void
+_shift_data_right(struct xdr_buf *buf, size_t to, size_t from, size_t len)
+{
+	size_t shift = len;
+
+	if ((to + len) > buf->page_len) {
+		shift = (to + len) - buf->page_len;
+		_shift_data_right_tail(buf, (from + len) - shift, shift);
+		shift = len - shift;
+	}
+
+	_shift_data_right_pages(buf->pages,
+				buf->page_base + to,
+				buf->page_base + from,
+				shift);
+}
+
 /**
  * _copy_to_pages
  * @pages: array of pages
@@ -350,6 +384,33 @@ _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len)
 }
 EXPORT_SYMBOL_GPL(_copy_from_pages);
 
+/**
+ * _zero_data_pages
+ * @pages: array of pages
+ * @pgbase: beginning page vector address
+ * @len: length
+ */
+static void
+_zero_data_pages(struct page **pages, size_t pgbase, size_t len)
+{
+	struct page **page;
+	size_t zero;
+
+	page = pages + (pgbase >> PAGE_SHIFT);
+	pgbase &= ~PAGE_MASK;
+
+	do {
+		zero = len;
+		if (pgbase + zero > PAGE_SIZE)
+			zero = PAGE_SIZE - pgbase;
+
+		zero_user_segment(*page, pgbase, pgbase + zero);
+		page++;
+		pgbase = 0;
+
+	} while ((len -= zero) != 0);
+}
+
 /**
  * xdr_shrink_bufhead
  * @buf: xdr_buf
@@ -505,6 +566,24 @@ unsigned int xdr_stream_pos(const struct xdr_stream *xdr)
 }
 EXPORT_SYMBOL_GPL(xdr_stream_pos);
 
+/**
+ * xdr_page_pos - Return the current offset from the start of the xdr->buf->pages
+ * @xdr: pointer to struct xdr_stream
+ */
+static size_t xdr_page_pos(const struct xdr_stream *xdr)
+{
+	unsigned int offset;
+	unsigned int base = xdr->buf->page_len;
+	void *kaddr = xdr->buf->tail->iov_base;;
+
+	if (xdr->page_ptr) {
+		base   = (xdr->page_ptr - xdr->buf->pages) * PAGE_SIZE;
+		kaddr  = page_address(*xdr->page_ptr);
+	}
+	offset = xdr->p - (__be32 *)kaddr;
+	return base + (offset * sizeof(__be32));
+}
+
 /**
  * xdr_init_encode - Initialize a struct xdr_stream for sending data.
  * @xdr: pointer to xdr_stream struct
@@ -1062,6 +1141,27 @@ unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
 }
 EXPORT_SYMBOL_GPL(xdr_read_pages);
 
+size_t xdr_expand_hole(struct xdr_stream *xdr, size_t offset, uint64_t length)
+{
+	struct xdr_buf *buf = xdr->buf;
+	size_t from = 0;
+
+	if ((offset + length) < offset ||
+	    (offset + length) > buf->page_len)
+		length = buf->page_len - offset;
+
+	if (offset == 0)
+		xdr_align_pages(xdr, xdr->nwords << 2);
+	else
+		from = xdr_page_pos(xdr);
+
+	_shift_data_right(buf, offset + length, from, xdr->nwords << 2);
+	_zero_data_pages(buf->pages, buf->page_base + offset, length);
+	xdr_set_page(xdr, offset + length);
+	return length;
+}
+EXPORT_SYMBOL_GPL(xdr_expand_hole);
+
 /**
  * xdr_enter_page - decode data from the XDR page
  * @xdr: pointer to xdr_stream struct
-- 
2.24.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* [PATCH 3/7] SUNRPC: Add the ability to shift data to a specific offset
  2020-01-10 22:34 [PATCH 0/7] NFS: Add support for the v4.2 READ_PLUS operation schumaker.anna
  2020-01-10 22:34 ` [PATCH 1/7] SUNRPC: Split out a function for setting current page schumaker.anna
  2020-01-10 22:34 ` [PATCH 2/7] SUNRPC: Add the ability to expand holes in data pages schumaker.anna
@ 2020-01-10 22:34 ` schumaker.anna
  2020-01-10 22:34 ` [PATCH 4/7] NFS: Add READ_PLUS data segment support schumaker.anna
                   ` (3 subsequent siblings)
  6 siblings, 0 replies; 11+ messages in thread
From: schumaker.anna @ 2020-01-10 22:34 UTC (permalink / raw)
  To: Trond.Myklebust, linux-nfs; +Cc: Anna.Schumaker

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

Expanding holes tends to put the data content a few bytes to the right
of where we want it.  This patch implements a left-shift operation to
line everything up properly.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
 include/linux/sunrpc/xdr.h |   1 +
 net/sunrpc/xdr.c           | 135 +++++++++++++++++++++++++++++++++++++
 2 files changed, 136 insertions(+)

diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 81a79099ed3b..90abf732c8ee 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -264,6 +264,7 @@ 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 size_t xdr_expand_hole(struct xdr_stream *, size_t, uint64_t);
+extern uint64_t xdr_align_data(struct xdr_stream *, uint64_t, uint64_t);
 
 /**
  * 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 bc9b9b0945f5..a857c2308ee1 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -19,6 +19,9 @@
 #include <linux/bvec.h>
 #include <trace/events/sunrpc.h>
 
+static void _copy_to_pages(struct page **, size_t, const char *, size_t);
+
+
 /*
  * XDR functions for basic NFS types
  */
@@ -300,6 +303,117 @@ _shift_data_right(struct xdr_buf *buf, size_t to, size_t from, size_t len)
 				shift);
 }
 
+
+/**
+ * _shift_data_left_pages
+ * @pages: vector of pages containing both the source and dest memory area.
+ * @pgto_base: page vector address of destination
+ * @pgfrom_base: page vector address of source
+ * @len: number of bytes to copy
+ *
+ * Note: the addresses pgto_base and pgfrom_base are both calculated in
+ *       the same way:
+ *            if a memory area starts at byte 'base' in page 'pages[i]',
+ *            then its address is given as (i << PAGE_CACHE_SHIFT) + base
+ * Alse note: pgto_base must be < pgfrom_base, but the memory areas
+ * 	they point to may overlap.
+ */
+static void
+_shift_data_left_pages(struct page **pages, size_t pgto_base,
+			size_t pgfrom_base, size_t len)
+{
+	struct page **pgfrom, **pgto;
+	char *vfrom, *vto;
+	size_t copy;
+
+	BUG_ON(pgfrom_base <= pgto_base);
+
+	pgto = pages + (pgto_base >> PAGE_SHIFT);
+	pgfrom = pages + (pgfrom_base >> PAGE_SHIFT);
+
+	pgto_base = pgto_base % PAGE_SIZE;
+	pgfrom_base = pgfrom_base % PAGE_SIZE;
+
+	do {
+		if (pgto_base >= PAGE_SIZE) {
+			pgto_base = 0;
+			pgto++;
+		}
+		if (pgfrom_base >= PAGE_SIZE){
+			pgfrom_base = 0;
+			pgfrom++;
+		}
+
+		copy = len;
+		if (copy > (PAGE_SIZE - pgto_base))
+			copy = PAGE_SIZE - pgto_base;
+		if (copy > (PAGE_SIZE - pgfrom_base))
+			copy = PAGE_SIZE - pgfrom_base;
+
+		if (pgto_base == 131056)
+			break;
+
+		vto = kmap_atomic(*pgto);
+		if (*pgto != *pgfrom) {
+			vfrom = kmap_atomic(*pgfrom);
+			memcpy(vto + pgto_base, vfrom + pgfrom_base, copy);
+			kunmap_atomic(vfrom);
+		} else
+			memmove(vto + pgto_base, vto + pgfrom_base, copy);
+		flush_dcache_page(*pgto);
+		kunmap_atomic(vto);
+
+		pgto_base += copy;
+		pgfrom_base += copy;
+
+	} while ((len -= copy) != 0);
+}
+
+static void
+_shift_data_left_tail(struct xdr_buf *buf, size_t pgto_base,
+		      size_t tail_from, size_t len)
+{
+	struct kvec *tail = buf->tail;
+	size_t shift = len;
+
+	if (len == 0)
+		return;
+	if (pgto_base + len > buf->page_len)
+		shift = buf->page_len - pgto_base;
+
+	_copy_to_pages(buf->pages,
+			buf->page_base + pgto_base,
+			(char *)(tail->iov_base + tail_from),
+			shift);
+
+	memmove((char *)tail->iov_base, tail->iov_base + tail_from + shift, shift);
+	tail->iov_len -= (tail_from + shift);
+}
+
+static void
+_shift_data_left(struct xdr_buf *buf, size_t to, size_t from, size_t len)
+{
+	size_t shift = len;
+
+	if (from < buf->page_len) {
+		shift = min(len, buf->page_len - from);
+		_shift_data_left_pages(buf->pages,
+					buf->page_base + to,
+					buf->page_base + from,
+					shift);
+		to += shift;
+		from += shift;
+		shift = len - shift;
+	}
+
+	if (shift == 0)
+		return;
+	if (from >= buf->page_len)
+		from -= buf->page_len;
+
+	_shift_data_left_tail(buf, to, from, shift);
+}
+
 /**
  * _copy_to_pages
  * @pages: array of pages
@@ -1162,6 +1276,27 @@ size_t xdr_expand_hole(struct xdr_stream *xdr, size_t offset, uint64_t length)
 }
 EXPORT_SYMBOL_GPL(xdr_expand_hole);
 
+uint64_t xdr_align_data(struct xdr_stream *xdr, uint64_t offset, uint64_t length)
+{
+	struct xdr_buf *buf = xdr->buf;
+	size_t from = offset;
+
+	if (offset + length > buf->page_len)
+		length = buf->page_len - offset;
+
+	if (offset == 0)
+		xdr_align_pages(xdr, xdr->nwords << 2);
+	else {
+		from = xdr_page_pos(xdr);
+		_shift_data_left(buf, offset, from, length);
+	}
+
+	xdr->nwords -= XDR_QUADLEN(length);
+	xdr_set_page(xdr, from + length);
+	return length;
+}
+EXPORT_SYMBOL_GPL(xdr_align_data);
+
 /**
  * xdr_enter_page - decode data from the XDR page
  * @xdr: pointer to xdr_stream struct
-- 
2.24.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* [PATCH 4/7] NFS: Add READ_PLUS data segment support
  2020-01-10 22:34 [PATCH 0/7] NFS: Add support for the v4.2 READ_PLUS operation schumaker.anna
                   ` (2 preceding siblings ...)
  2020-01-10 22:34 ` [PATCH 3/7] SUNRPC: Add the ability to shift data to a specific offset schumaker.anna
@ 2020-01-10 22:34 ` schumaker.anna
  2020-01-10 22:34 ` [PATCH 5/7] NFS: Add READ_PLUS hole segment decoding schumaker.anna
                   ` (2 subsequent siblings)
  6 siblings, 0 replies; 11+ messages in thread
From: schumaker.anna @ 2020-01-10 22:34 UTC (permalink / raw)
  To: Trond.Myklebust, linux-nfs; +Cc: Anna.Schumaker

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

This patch adds client support for decoding a single NFS4_CONTENT_DATA
segment returned by the server. This is the simplest implementation
possible, since it does not account for any hole segments in the reply.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
 fs/nfs/nfs42xdr.c         | 138 ++++++++++++++++++++++++++++++++++++++
 fs/nfs/nfs4proc.c         |  32 ++++++++-
 fs/nfs/nfs4xdr.c          |   1 +
 include/linux/nfs4.h      |   2 +-
 include/linux/nfs_fs_sb.h |   1 +
 include/linux/nfs_xdr.h   |   2 +-
 6 files changed, 171 insertions(+), 5 deletions(-)

diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index c03f3246d6c5..bf118ecabe2c 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -45,6 +45,15 @@
 #define encode_deallocate_maxsz		(op_encode_hdr_maxsz + \
 					 encode_fallocate_maxsz)
 #define decode_deallocate_maxsz		(op_decode_hdr_maxsz)
+#define encode_read_plus_maxsz		(op_encode_hdr_maxsz + \
+					 encode_stateid_maxsz + 3)
+#define NFS42_READ_PLUS_SEGMENT_SIZE	(1 /* data_content4 */ + \
+					 2 /* data_info4.di_offset */ + \
+					 2 /* data_info4.di_length */)
+#define decode_read_plus_maxsz		(op_decode_hdr_maxsz + \
+					 1 /* rpr_eof */ + \
+					 1 /* rpr_contents count */ + \
+					 NFS42_READ_PLUS_SEGMENT_SIZE)
 #define encode_seek_maxsz		(op_encode_hdr_maxsz + \
 					 encode_stateid_maxsz + \
 					 2 /* offset */ + \
@@ -128,6 +137,14 @@
 					 decode_putfh_maxsz + \
 					 decode_deallocate_maxsz + \
 					 decode_getattr_maxsz)
+#define NFS4_enc_read_plus_sz		(compound_encode_hdr_maxsz + \
+					 encode_sequence_maxsz + \
+					 encode_putfh_maxsz + \
+					 encode_read_plus_maxsz)
+#define NFS4_dec_read_plus_sz		(compound_decode_hdr_maxsz + \
+					 decode_sequence_maxsz + \
+					 decode_putfh_maxsz + \
+					 decode_read_plus_maxsz)
 #define NFS4_enc_seek_sz		(compound_encode_hdr_maxsz + \
 					 encode_sequence_maxsz + \
 					 encode_putfh_maxsz + \
@@ -252,6 +269,16 @@ static void encode_deallocate(struct xdr_stream *xdr,
 	encode_fallocate(xdr, args);
 }
 
+static void encode_read_plus(struct xdr_stream *xdr,
+			     const struct nfs_pgio_args *args,
+			     struct compound_hdr *hdr)
+{
+	encode_op_hdr(xdr, OP_READ_PLUS, decode_read_plus_maxsz, hdr);
+	encode_nfs4_stateid(xdr, &args->stateid);
+	encode_uint64(xdr, args->offset);
+	encode_uint32(xdr, args->count);
+}
+
 static void encode_seek(struct xdr_stream *xdr,
 			const struct nfs42_seek_args *args,
 			struct compound_hdr *hdr)
@@ -446,6 +473,29 @@ static void nfs4_xdr_enc_deallocate(struct rpc_rqst *req,
 	encode_nops(&hdr);
 }
 
+/*
+ * Encode READ_PLUS request
+ */
+static void nfs4_xdr_enc_read_plus(struct rpc_rqst *req,
+				   struct xdr_stream *xdr,
+				   const void *data)
+{
+	const struct nfs_pgio_args *args = data;
+	struct compound_hdr hdr = {
+		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
+	};
+
+	encode_compound_hdr(xdr, req, &hdr);
+	encode_sequence(xdr, &args->seq_args, &hdr);
+	encode_putfh(xdr, args->fh, &hdr);
+	encode_read_plus(xdr, args, &hdr);
+
+	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
+				args->count, hdr.replen);
+	req->rq_rcv_buf.flags |= XDRBUF_READ;
+	encode_nops(&hdr);
+}
+
 /*
  * Encode SEEK request
  */
@@ -694,6 +744,67 @@ static int decode_deallocate(struct xdr_stream *xdr, struct nfs42_falloc_res *re
 	return decode_op_hdr(xdr, OP_DEALLOCATE);
 }
 
+static uint32_t decode_read_plus_data(struct xdr_stream *xdr, struct nfs_pgio_res *res,
+				      uint32_t *eof)
+{
+	__be32 *p;
+	uint32_t count, recvd;
+	uint64_t offset;
+
+	p = xdr_inline_decode(xdr, 8 + 4);
+	if (unlikely(!p))
+		return -EIO;
+
+	p = xdr_decode_hyper(p, &offset);
+	count = be32_to_cpup(p);
+	if (count == 0)
+		return 0;
+
+	recvd = xdr_read_pages(xdr, count);
+	if (count > recvd) {
+		dprintk("NFS: server cheating in read reply: "
+				"count %u > recvd %u\n", count, recvd);
+		count = recvd;
+		*eof = 0;
+	}
+
+	return count;
+}
+
+static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
+{
+	__be32 *p;
+	uint32_t count, eof, segments, type;
+	int status;
+
+	status = decode_op_hdr(xdr, OP_READ_PLUS);
+	if (status)
+		return status;
+
+	p = xdr_inline_decode(xdr, 4 + 4);
+	if (unlikely(!p))
+		return -EIO;
+
+	eof = be32_to_cpup(p++);
+	segments = be32_to_cpup(p++);
+	if (segments == 0)
+		return 0;
+
+	p = xdr_inline_decode(xdr, 4);
+	if (unlikely(!p))
+		return -EIO;
+
+	type = be32_to_cpup(p++);
+	if (type == NFS4_CONTENT_DATA)
+		count = decode_read_plus_data(xdr, res, &eof);
+	else
+		return -EINVAL;
+
+	res->eof = eof;
+	res->count = count;
+	return 0;
+}
+
 static int decode_seek(struct xdr_stream *xdr, struct nfs42_seek_res *res)
 {
 	int status;
@@ -870,6 +981,33 @@ static int nfs4_xdr_dec_deallocate(struct rpc_rqst *rqstp,
 	return status;
 }
 
+/*
+ * Decode READ_PLUS request
+ */
+static int nfs4_xdr_dec_read_plus(struct rpc_rqst *rqstp,
+				  struct xdr_stream *xdr,
+				  void *data)
+{
+	struct nfs_pgio_res *res = data;
+	struct compound_hdr hdr;
+	int status;
+
+	status = decode_compound_hdr(xdr, &hdr);
+	if (status)
+		goto out;
+	status = decode_sequence(xdr, &res->seq_res, rqstp);
+	if (status)
+		goto out;
+	status = decode_putfh(xdr);
+	if (status)
+		goto out;
+	status = decode_read_plus(xdr, res);
+	if (!status)
+		status = res->count;
+out:
+	return status;
+}
+
 /*
  * Decode SEEK request
  */
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 64bbb0d0ff5a..60b1ec684751 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -69,6 +69,10 @@
 
 #include "nfs4trace.h"
 
+#ifdef CONFIG_NFS_V4_2
+#include "nfs42.h"
+#endif /* CONFIG_NFS_V4_2 */
+
 #define NFSDBG_FACILITY		NFSDBG_PROC
 
 #define NFS4_BITMASK_SZ		3
@@ -5195,9 +5199,15 @@ static bool nfs4_read_stateid_changed(struct rpc_task *task,
 
 static int nfs4_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
 {
-
+	struct nfs_server *server = NFS_SERVER(hdr->inode);
 	dprintk("--> %s\n", __func__);
 
+	if ((server->caps & NFS_CAP_READ_PLUS) && (task->tk_status == -ENOTSUPP)) {
+		server->caps &= ~NFS_CAP_READ_PLUS;
+		if (rpc_restart_call_prepare(task))
+			task->tk_status = 0;
+		return -EAGAIN;
+	}
 	if (!nfs4_sequence_done(task, &hdr->res.seq_res))
 		return -EAGAIN;
 	if (nfs4_read_stateid_changed(task, &hdr->args))
@@ -5208,13 +5218,28 @@ static int nfs4_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
 				    nfs4_read_done_cb(task, hdr);
 }
 
+#ifdef CONFIG_NFS_V4_2
+static void nfs42_read_plus_support(struct nfs_server *server, struct rpc_message *msg)
+{
+	if (server->caps & NFS_CAP_READ_PLUS)
+		msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ_PLUS];
+	else
+		msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ];
+}
+#else
+static void nfs42_read_plus_support(struct nfs_server *server, struct rpc_message *msg)
+{
+	msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ];
+}
+#endif /* CONFIG_NFS_V4_2 */
+
 static void nfs4_proc_read_setup(struct nfs_pgio_header *hdr,
 				 struct rpc_message *msg)
 {
 	hdr->timestamp   = jiffies;
 	if (!hdr->pgio_done_cb)
 		hdr->pgio_done_cb = nfs4_read_done_cb;
-	msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ];
+	nfs42_read_plus_support(NFS_SERVER(hdr->inode), msg);
 	nfs4_init_sequence(&hdr->args.seq_args, &hdr->res.seq_res, 0, 0);
 }
 
@@ -9957,7 +9982,8 @@ static const struct nfs4_minor_version_ops nfs_v4_2_minor_ops = {
 		| NFS_CAP_SEEK
 		| NFS_CAP_LAYOUTSTATS
 		| NFS_CAP_CLONE
-		| NFS_CAP_LAYOUTERROR,
+		| NFS_CAP_LAYOUTERROR
+		| NFS_CAP_READ_PLUS,
 	.init_client = nfs41_init_client,
 	.shutdown_client = nfs41_shutdown_client,
 	.match_stateid = nfs41_match_stateid,
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 02890606e14a..dd81c9ddd0fb 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -7593,6 +7593,7 @@ const struct rpc_procinfo nfs4_procedures[] = {
 	PROC42(COPY_NOTIFY,	enc_copy_notify,	dec_copy_notify),
 	PROC(LOOKUPP,		enc_lookupp,		dec_lookupp),
 	PROC42(LAYOUTERROR,	enc_layouterror,	dec_layouterror),
+	PROC42(READ_PLUS,	enc_read_plus,		dec_read_plus),
 };
 
 static unsigned int nfs_version4_counts[ARRAY_SIZE(nfs4_procedures)];
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 82d8fb422092..c1eeef52545c 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -540,8 +540,8 @@ enum {
 
 	NFSPROC4_CLNT_LOOKUPP,
 	NFSPROC4_CLNT_LAYOUTERROR,
-
 	NFSPROC4_CLNT_COPY_NOTIFY,
+	NFSPROC4_CLNT_READ_PLUS,
 };
 
 /* nfs41 types */
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 465fa98258a3..11248c5a7b24 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -281,5 +281,6 @@ struct nfs_server {
 #define NFS_CAP_OFFLOAD_CANCEL	(1U << 25)
 #define NFS_CAP_LAYOUTERROR	(1U << 26)
 #define NFS_CAP_COPY_NOTIFY	(1U << 27)
+#define NFS_CAP_READ_PLUS	(1U << 28)
 
 #endif
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index bb8652792b84..412297a10878 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -655,7 +655,7 @@ struct nfs_pgio_args {
 struct nfs_pgio_res {
 	struct nfs4_sequence_res	seq_res;
 	struct nfs_fattr *	fattr;
-	__u32			count;
+	__u64			count;
 	__u32			op_status;
 	union {
 		struct {
-- 
2.24.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* [PATCH 5/7] NFS: Add READ_PLUS hole segment decoding
  2020-01-10 22:34 [PATCH 0/7] NFS: Add support for the v4.2 READ_PLUS operation schumaker.anna
                   ` (3 preceding siblings ...)
  2020-01-10 22:34 ` [PATCH 4/7] NFS: Add READ_PLUS data segment support schumaker.anna
@ 2020-01-10 22:34 ` schumaker.anna
  2020-01-10 22:34 ` [PATCH 6/7] NFS: Decode multiple READ_PLUS segments schumaker.anna
  2020-01-10 22:34 ` [PATCH 7/7] NFS: Add a mount option for READ_PLUS schumaker.anna
  6 siblings, 0 replies; 11+ messages in thread
From: schumaker.anna @ 2020-01-10 22:34 UTC (permalink / raw)
  To: Trond.Myklebust, linux-nfs; +Cc: Anna.Schumaker

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

We keep things simple for now by only decoding a single hole or data
segment returned by the server, even if they returned more to us.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
 fs/nfs/nfs42xdr.c | 32 ++++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index bf118ecabe2c..3407a3cf2e13 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -47,7 +47,7 @@
 #define decode_deallocate_maxsz		(op_decode_hdr_maxsz)
 #define encode_read_plus_maxsz		(op_encode_hdr_maxsz + \
 					 encode_stateid_maxsz + 3)
-#define NFS42_READ_PLUS_SEGMENT_SIZE	(1 /* data_content4 */ + \
+#define NFS42_READ_PLUS_SEGMENT_SIZE	(2 /* data_content4 */ + \
 					 2 /* data_info4.di_offset */ + \
 					 2 /* data_info4.di_length */)
 #define decode_read_plus_maxsz		(op_decode_hdr_maxsz + \
@@ -771,6 +771,31 @@ static uint32_t decode_read_plus_data(struct xdr_stream *xdr, struct nfs_pgio_re
 	return count;
 }
 
+static uint32_t decode_read_plus_hole(struct xdr_stream *xdr, struct nfs_pgio_res *res,
+				      uint32_t *eof)
+{
+	__be32 *p;
+	uint64_t offset, length;
+	size_t recvd;
+
+	p = xdr_inline_decode(xdr, 8 + 8);
+	if (unlikely(!p))
+		return -EIO;
+
+	p = xdr_decode_hyper(p, &offset);
+	p = xdr_decode_hyper(p, &length);
+	if (length == 0)
+		return 0;
+
+	recvd = xdr_expand_hole(xdr, 0, length);
+	if (recvd < length) {
+		*eof = 0;
+		length = recvd;
+	}
+
+	return length;
+}
+
 static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
 {
 	__be32 *p;
@@ -798,7 +823,10 @@ static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
 	if (type == NFS4_CONTENT_DATA)
 		count = decode_read_plus_data(xdr, res, &eof);
 	else
-		return -EINVAL;
+		count = decode_read_plus_hole(xdr, res, &eof);
+
+	if (segments > 1)
+		eof = 0;
 
 	res->eof = eof;
 	res->count = count;
-- 
2.24.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* [PATCH 6/7] NFS: Decode multiple READ_PLUS segments
  2020-01-10 22:34 [PATCH 0/7] NFS: Add support for the v4.2 READ_PLUS operation schumaker.anna
                   ` (4 preceding siblings ...)
  2020-01-10 22:34 ` [PATCH 5/7] NFS: Add READ_PLUS hole segment decoding schumaker.anna
@ 2020-01-10 22:34 ` schumaker.anna
  2020-01-10 22:34 ` [PATCH 7/7] NFS: Add a mount option for READ_PLUS schumaker.anna
  6 siblings, 0 replies; 11+ messages in thread
From: schumaker.anna @ 2020-01-10 22:34 UTC (permalink / raw)
  To: Trond.Myklebust, linux-nfs; +Cc: Anna.Schumaker

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

We now have everything we need to read holes and shift data to where
it's supposed to be. I switch over to using xdr_align_data() to put data
segments in the proper place.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
 fs/nfs/nfs42xdr.c | 43 +++++++++++++++++++++++--------------------
 1 file changed, 23 insertions(+), 20 deletions(-)

diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index 3407a3cf2e13..b5c638bcab66 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -53,7 +53,7 @@
 #define decode_read_plus_maxsz		(op_decode_hdr_maxsz + \
 					 1 /* rpr_eof */ + \
 					 1 /* rpr_contents count */ + \
-					 NFS42_READ_PLUS_SEGMENT_SIZE)
+					 (2 * NFS42_READ_PLUS_SEGMENT_SIZE))
 #define encode_seek_maxsz		(op_encode_hdr_maxsz + \
 					 encode_stateid_maxsz + \
 					 2 /* offset */ + \
@@ -745,7 +745,7 @@ static int decode_deallocate(struct xdr_stream *xdr, struct nfs42_falloc_res *re
 }
 
 static uint32_t decode_read_plus_data(struct xdr_stream *xdr, struct nfs_pgio_res *res,
-				      uint32_t *eof)
+				      uint32_t *eof, uint64_t total)
 {
 	__be32 *p;
 	uint32_t count, recvd;
@@ -760,7 +760,7 @@ static uint32_t decode_read_plus_data(struct xdr_stream *xdr, struct nfs_pgio_re
 	if (count == 0)
 		return 0;
 
-	recvd = xdr_read_pages(xdr, count);
+	recvd = xdr_align_data(xdr, total, count);
 	if (count > recvd) {
 		dprintk("NFS: server cheating in read reply: "
 				"count %u > recvd %u\n", count, recvd);
@@ -772,7 +772,7 @@ static uint32_t decode_read_plus_data(struct xdr_stream *xdr, struct nfs_pgio_re
 }
 
 static uint32_t decode_read_plus_hole(struct xdr_stream *xdr, struct nfs_pgio_res *res,
-				      uint32_t *eof)
+				     uint32_t *eof, uint64_t total)
 {
 	__be32 *p;
 	uint64_t offset, length;
@@ -787,7 +787,7 @@ static uint32_t decode_read_plus_hole(struct xdr_stream *xdr, struct nfs_pgio_re
 	if (length == 0)
 		return 0;
 
-	recvd = xdr_expand_hole(xdr, 0, length);
+	recvd = xdr_expand_hole(xdr, total, length);
 	if (recvd < length) {
 		*eof = 0;
 		length = recvd;
@@ -799,8 +799,9 @@ static uint32_t decode_read_plus_hole(struct xdr_stream *xdr, struct nfs_pgio_re
 static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
 {
 	__be32 *p;
-	uint32_t count, eof, segments, type;
-	int status;
+	uint32_t eof, segments, type, total;
+	int32_t count;
+	int status, i;
 
 	status = decode_op_hdr(xdr, OP_READ_PLUS);
 	if (status)
@@ -810,26 +811,28 @@ static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
 	if (unlikely(!p))
 		return -EIO;
 
+	total = 0;
 	eof = be32_to_cpup(p++);
 	segments = be32_to_cpup(p++);
-	if (segments == 0)
-		return 0;
 
-	p = xdr_inline_decode(xdr, 4);
-	if (unlikely(!p))
-		return -EIO;
+	for (i = 0; i < segments; i++) {
+		p = xdr_inline_decode(xdr, 4);
+		if (unlikely(!p))
+			return -EIO;
 
-	type = be32_to_cpup(p++);
-	if (type == NFS4_CONTENT_DATA)
-		count = decode_read_plus_data(xdr, res, &eof);
-	else
-		count = decode_read_plus_hole(xdr, res, &eof);
+		type = be32_to_cpup(p);
+		if (type == NFS4_CONTENT_DATA)
+			count = decode_read_plus_data(xdr, res, &eof, total);
+		else
+			count = decode_read_plus_hole(xdr, res, &eof, total);
 
-	if (segments > 1)
-		eof = 0;
+		if (count < 0)
+			return count;
+		total += count;
+	}
 
 	res->eof = eof;
-	res->count = count;
+	res->count = total;
 	return 0;
 }
 
-- 
2.24.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* [PATCH 7/7] NFS: Add a mount option for READ_PLUS
  2020-01-10 22:34 [PATCH 0/7] NFS: Add support for the v4.2 READ_PLUS operation schumaker.anna
                   ` (5 preceding siblings ...)
  2020-01-10 22:34 ` [PATCH 6/7] NFS: Decode multiple READ_PLUS segments schumaker.anna
@ 2020-01-10 22:34 ` schumaker.anna
  2020-01-10 22:41   ` Chuck Lever
  6 siblings, 1 reply; 11+ messages in thread
From: schumaker.anna @ 2020-01-10 22:34 UTC (permalink / raw)
  To: Trond.Myklebust, linux-nfs; +Cc: Anna.Schumaker

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

There are some workloads where READ_PLUS might end up hurting
performance, so let's be nice to users and provide a way to disable this
operation similar to how READDIR_PLUS can be disabled.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
 fs/nfs/fs_context.c       | 14 ++++++++++++++
 fs/nfs/nfs4client.c       |  3 +++
 include/linux/nfs_fs_sb.h |  1 +
 3 files changed, 18 insertions(+)

diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
index 0247dcb7b316..82ba07c7c1ce 100644
--- a/fs/nfs/fs_context.c
+++ b/fs/nfs/fs_context.c
@@ -64,6 +64,7 @@ enum nfs_param {
 	Opt_proto,
 	Opt_rdirplus,
 	Opt_rdma,
+	Opt_readplus,
 	Opt_resvport,
 	Opt_retrans,
 	Opt_retry,
@@ -120,6 +121,7 @@ static const struct fs_parameter_spec nfs_param_specs[] = {
 	fsparam_string("proto",		Opt_proto),
 	fsparam_flag_no("rdirplus",	Opt_rdirplus),
 	fsparam_flag  ("rdma",		Opt_rdma),
+	fsparam_flag_no("readplus",	Opt_readplus),
 	fsparam_flag_no("resvport",	Opt_resvport),
 	fsparam_u32   ("retrans",	Opt_retrans),
 	fsparam_string("retry",		Opt_retry),
@@ -555,6 +557,12 @@ static int nfs_fs_context_parse_param(struct fs_context *fc,
 		else
 			ctx->options |= NFS_OPTION_MIGRATION;
 		break;
+	case Opt_readplus:
+		if (result.negated)
+			ctx->options |= NFS_OPTION_NO_READ_PLUS;
+		else
+			ctx->options &= ~NFS_OPTION_NO_READ_PLUS;
+		break;
 
 		/*
 		 * options that take numeric values
@@ -1176,6 +1184,10 @@ static int nfs_fs_context_validate(struct fs_context *fc)
 	    (ctx->version != 4 || ctx->minorversion != 0))
 		goto out_migration_misuse;
 
+	if (ctx->options & NFS_OPTION_NO_READ_PLUS &&
+	    (ctx->version != 4 || ctx->minorversion < 2))
+		goto out_noreadplus_misuse;
+
 	/* Verify that any proto=/mountproto= options match the address
 	 * families in the addr=/mountaddr= options.
 	 */
@@ -1254,6 +1266,8 @@ static int nfs_fs_context_validate(struct fs_context *fc)
 			  ctx->version, ctx->minorversion);
 out_migration_misuse:
 	return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
+out_noreadplus_misuse:
+	return nfs_invalf(fc, "NFS: 'noreadplus' not supported for this NFS version\n");
 out_version_unavailable:
 	nfs_errorf(fc, "NFS: Version unavailable");
 	return ret;
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
index 0cd767e5c977..868dc3c36ba1 100644
--- a/fs/nfs/nfs4client.c
+++ b/fs/nfs/nfs4client.c
@@ -1016,6 +1016,9 @@ static int nfs4_server_common_setup(struct nfs_server *server,
 	server->caps |= server->nfs_client->cl_mvops->init_caps;
 	if (server->flags & NFS_MOUNT_NORDIRPLUS)
 			server->caps &= ~NFS_CAP_READDIRPLUS;
+	if (server->options & NFS_OPTION_NO_READ_PLUS)
+		server->caps &= ~NFS_CAP_READ_PLUS;
+
 	/*
 	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
 	 * authentication.
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 11248c5a7b24..360e70c7bbb6 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -172,6 +172,7 @@ struct nfs_server {
 	unsigned int		clone_blksize;	/* granularity of a CLONE operation */
 #define NFS_OPTION_FSCACHE	0x00000001	/* - local caching enabled */
 #define NFS_OPTION_MIGRATION	0x00000002	/* - NFSv4 migration enabled */
+#define NFS_OPTION_NO_READ_PLUS	0x00000004	/* - NFSv4.2 READ_PLUS enabled */
 
 	struct nfs_fsid		fsid;
 	__u64			maxfilesize;	/* maximum file size */
-- 
2.24.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH 7/7] NFS: Add a mount option for READ_PLUS
  2020-01-10 22:34 ` [PATCH 7/7] NFS: Add a mount option for READ_PLUS schumaker.anna
@ 2020-01-10 22:41   ` Chuck Lever
  2020-01-10 22:43     ` Schumaker, Anna
  0 siblings, 1 reply; 11+ messages in thread
From: Chuck Lever @ 2020-01-10 22:41 UTC (permalink / raw)
  To: Anna Schumaker; +Cc: Trond.Myklebust, Linux NFS Mailing List, Anna Schumaker

Hi Anna-

> On Jan 10, 2020, at 5:34 PM, schumaker.anna@gmail.com wrote:
> 
> From: Anna Schumaker <Anna.Schumaker@Netapp.com>
> 
> There are some workloads where READ_PLUS might end up hurting
> performance,

Can you say more about this? Have you seen workloads that are
hurt by READ_PLUS? Nothing jumps out at me from the tables in
the cover letter.


> so let's be nice to users and provide a way to disable this
> operation similar to how READDIR_PLUS can be disabled.

Does it make sense to hold off on a mount option until there
is evidence that there is no other way to work around such a
performance regression?

- Attempt to address the regression directly
- Improve the heuristics about when READ_PLUS is used
- Document that dropping back to vers=4.1 will disable it

Any experience with NFS/RDMA?


> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
> ---
> fs/nfs/fs_context.c       | 14 ++++++++++++++
> fs/nfs/nfs4client.c       |  3 +++
> include/linux/nfs_fs_sb.h |  1 +
> 3 files changed, 18 insertions(+)
> 
> diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
> index 0247dcb7b316..82ba07c7c1ce 100644
> --- a/fs/nfs/fs_context.c
> +++ b/fs/nfs/fs_context.c
> @@ -64,6 +64,7 @@ enum nfs_param {
> 	Opt_proto,
> 	Opt_rdirplus,
> 	Opt_rdma,
> +	Opt_readplus,
> 	Opt_resvport,
> 	Opt_retrans,
> 	Opt_retry,
> @@ -120,6 +121,7 @@ static const struct fs_parameter_spec nfs_param_specs[] = {
> 	fsparam_string("proto",		Opt_proto),
> 	fsparam_flag_no("rdirplus",	Opt_rdirplus),
> 	fsparam_flag  ("rdma",		Opt_rdma),
> +	fsparam_flag_no("readplus",	Opt_readplus),
> 	fsparam_flag_no("resvport",	Opt_resvport),
> 	fsparam_u32   ("retrans",	Opt_retrans),
> 	fsparam_string("retry",		Opt_retry),
> @@ -555,6 +557,12 @@ static int nfs_fs_context_parse_param(struct fs_context *fc,
> 		else
> 			ctx->options |= NFS_OPTION_MIGRATION;
> 		break;
> +	case Opt_readplus:
> +		if (result.negated)
> +			ctx->options |= NFS_OPTION_NO_READ_PLUS;
> +		else
> +			ctx->options &= ~NFS_OPTION_NO_READ_PLUS;
> +		break;
> 
> 		/*
> 		 * options that take numeric values
> @@ -1176,6 +1184,10 @@ static int nfs_fs_context_validate(struct fs_context *fc)
> 	    (ctx->version != 4 || ctx->minorversion != 0))
> 		goto out_migration_misuse;
> 
> +	if (ctx->options & NFS_OPTION_NO_READ_PLUS &&
> +	    (ctx->version != 4 || ctx->minorversion < 2))
> +		goto out_noreadplus_misuse;
> +
> 	/* Verify that any proto=/mountproto= options match the address
> 	 * families in the addr=/mountaddr= options.
> 	 */
> @@ -1254,6 +1266,8 @@ static int nfs_fs_context_validate(struct fs_context *fc)
> 			  ctx->version, ctx->minorversion);
> out_migration_misuse:
> 	return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
> +out_noreadplus_misuse:
> +	return nfs_invalf(fc, "NFS: 'noreadplus' not supported for this NFS version\n");
> out_version_unavailable:
> 	nfs_errorf(fc, "NFS: Version unavailable");
> 	return ret;
> diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
> index 0cd767e5c977..868dc3c36ba1 100644
> --- a/fs/nfs/nfs4client.c
> +++ b/fs/nfs/nfs4client.c
> @@ -1016,6 +1016,9 @@ static int nfs4_server_common_setup(struct nfs_server *server,
> 	server->caps |= server->nfs_client->cl_mvops->init_caps;
> 	if (server->flags & NFS_MOUNT_NORDIRPLUS)
> 			server->caps &= ~NFS_CAP_READDIRPLUS;
> +	if (server->options & NFS_OPTION_NO_READ_PLUS)
> +		server->caps &= ~NFS_CAP_READ_PLUS;
> +
> 	/*
> 	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
> 	 * authentication.
> diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
> index 11248c5a7b24..360e70c7bbb6 100644
> --- a/include/linux/nfs_fs_sb.h
> +++ b/include/linux/nfs_fs_sb.h
> @@ -172,6 +172,7 @@ struct nfs_server {
> 	unsigned int		clone_blksize;	/* granularity of a CLONE operation */
> #define NFS_OPTION_FSCACHE	0x00000001	/* - local caching enabled */
> #define NFS_OPTION_MIGRATION	0x00000002	/* - NFSv4 migration enabled */
> +#define NFS_OPTION_NO_READ_PLUS	0x00000004	/* - NFSv4.2 READ_PLUS enabled */
> 
> 	struct nfs_fsid		fsid;
> 	__u64			maxfilesize;	/* maximum file size */
> -- 
> 2.24.1
> 

--
Chuck Lever




^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH 7/7] NFS: Add a mount option for READ_PLUS
  2020-01-10 22:41   ` Chuck Lever
@ 2020-01-10 22:43     ` Schumaker, Anna
  2020-01-10 22:45       ` Chuck Lever
  0 siblings, 1 reply; 11+ messages in thread
From: Schumaker, Anna @ 2020-01-10 22:43 UTC (permalink / raw)
  To: chuck.lever; +Cc: linux-nfs, Trond.Myklebust

Hi Chuck,

On Fri, 2020-01-10 at 17:41 -0500, Chuck Lever wrote:
> NetApp Security WARNING: This is an external email. Do not click links or open
> attachments unless you recognize the sender and know the content is safe.
> 
> 
> 
> 
> Hi Anna-
> 
> > On Jan 10, 2020, at 5:34 PM, schumaker.anna@gmail.com wrote:
> > 
> > From: Anna Schumaker <Anna.Schumaker@Netapp.com>
> > 
> > There are some workloads where READ_PLUS might end up hurting
> > performance,
> 
> Can you say more about this? Have you seen workloads that are
> hurt by READ_PLUS? Nothing jumps out at me from the tables in
> the cover letter.

It's mostly something I've seen when using btrfs in a virtual machine (so
probably not a wide use case, and it's possible I need to change something in my
setup to get it working better).

> 
> 
> > so let's be nice to users and provide a way to disable this
> > operation similar to how READDIR_PLUS can be disabled.
> 
> Does it make sense to hold off on a mount option until there
> is evidence that there is no other way to work around such a
> performance regression?
> 
> - Attempt to address the regression directly
> - Improve the heuristics about when READ_PLUS is used
> - Document that dropping back to vers=4.1 will disable it

Yeah, we could hold off on the patch for now and see if anybody has any issues
first.

> 
> Any experience with NFS/RDMA?

Not yet, but I can try to test that next week.

Anna

> 
> 
> > Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
> > ---
> > fs/nfs/fs_context.c       | 14 ++++++++++++++
> > fs/nfs/nfs4client.c       |  3 +++
> > include/linux/nfs_fs_sb.h |  1 +
> > 3 files changed, 18 insertions(+)
> > 
> > diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
> > index 0247dcb7b316..82ba07c7c1ce 100644
> > --- a/fs/nfs/fs_context.c
> > +++ b/fs/nfs/fs_context.c
> > @@ -64,6 +64,7 @@ enum nfs_param {
> >       Opt_proto,
> >       Opt_rdirplus,
> >       Opt_rdma,
> > +     Opt_readplus,
> >       Opt_resvport,
> >       Opt_retrans,
> >       Opt_retry,
> > @@ -120,6 +121,7 @@ static const struct fs_parameter_spec nfs_param_specs[]
> > = {
> >       fsparam_string("proto",         Opt_proto),
> >       fsparam_flag_no("rdirplus",     Opt_rdirplus),
> >       fsparam_flag  ("rdma",          Opt_rdma),
> > +     fsparam_flag_no("readplus",     Opt_readplus),
> >       fsparam_flag_no("resvport",     Opt_resvport),
> >       fsparam_u32   ("retrans",       Opt_retrans),
> >       fsparam_string("retry",         Opt_retry),
> > @@ -555,6 +557,12 @@ static int nfs_fs_context_parse_param(struct fs_context
> > *fc,
> >               else
> >                       ctx->options |= NFS_OPTION_MIGRATION;
> >               break;
> > +     case Opt_readplus:
> > +             if (result.negated)
> > +                     ctx->options |= NFS_OPTION_NO_READ_PLUS;
> > +             else
> > +                     ctx->options &= ~NFS_OPTION_NO_READ_PLUS;
> > +             break;
> > 
> >               /*
> >                * options that take numeric values
> > @@ -1176,6 +1184,10 @@ static int nfs_fs_context_validate(struct fs_context
> > *fc)
> >           (ctx->version != 4 || ctx->minorversion != 0))
> >               goto out_migration_misuse;
> > 
> > +     if (ctx->options & NFS_OPTION_NO_READ_PLUS &&
> > +         (ctx->version != 4 || ctx->minorversion < 2))
> > +             goto out_noreadplus_misuse;
> > +
> >       /* Verify that any proto=/mountproto= options match the address
> >        * families in the addr=/mountaddr= options.
> >        */
> > @@ -1254,6 +1266,8 @@ static int nfs_fs_context_validate(struct fs_context
> > *fc)
> >                         ctx->version, ctx->minorversion);
> > out_migration_misuse:
> >       return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS
> > version");
> > +out_noreadplus_misuse:
> > +     return nfs_invalf(fc, "NFS: 'noreadplus' not supported for this NFS
> > version\n");
> > out_version_unavailable:
> >       nfs_errorf(fc, "NFS: Version unavailable");
> >       return ret;
> > diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
> > index 0cd767e5c977..868dc3c36ba1 100644
> > --- a/fs/nfs/nfs4client.c
> > +++ b/fs/nfs/nfs4client.c
> > @@ -1016,6 +1016,9 @@ static int nfs4_server_common_setup(struct nfs_server
> > *server,
> >       server->caps |= server->nfs_client->cl_mvops->init_caps;
> >       if (server->flags & NFS_MOUNT_NORDIRPLUS)
> >                       server->caps &= ~NFS_CAP_READDIRPLUS;
> > +     if (server->options & NFS_OPTION_NO_READ_PLUS)
> > +             server->caps &= ~NFS_CAP_READ_PLUS;
> > +
> >       /*
> >        * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
> >        * authentication.
> > diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
> > index 11248c5a7b24..360e70c7bbb6 100644
> > --- a/include/linux/nfs_fs_sb.h
> > +++ b/include/linux/nfs_fs_sb.h
> > @@ -172,6 +172,7 @@ struct nfs_server {
> >       unsigned int            clone_blksize;  /* granularity of a CLONE
> > operation */
> > #define NFS_OPTION_FSCACHE    0x00000001      /* - local caching enabled */
> > #define NFS_OPTION_MIGRATION  0x00000002      /* - NFSv4 migration enabled
> > */
> > +#define NFS_OPTION_NO_READ_PLUS      0x00000004      /* - NFSv4.2 READ_PLUS
> > enabled */
> > 
> >       struct nfs_fsid         fsid;
> >       __u64                   maxfilesize;    /* maximum file size */
> > --
> > 2.24.1
> > 
> 
> --
> Chuck Lever
> 
> 
> 

^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH 7/7] NFS: Add a mount option for READ_PLUS
  2020-01-10 22:43     ` Schumaker, Anna
@ 2020-01-10 22:45       ` Chuck Lever
  0 siblings, 0 replies; 11+ messages in thread
From: Chuck Lever @ 2020-01-10 22:45 UTC (permalink / raw)
  To: Anna Schumaker; +Cc: Linux NFS Mailing List, Trond.Myklebust



> On Jan 10, 2020, at 5:43 PM, Schumaker, Anna <Anna.Schumaker@netapp.com> wrote:
> 
> Hi Chuck,
> 
> On Fri, 2020-01-10 at 17:41 -0500, Chuck Lever wrote:
>> NetApp Security WARNING: This is an external email. Do not click links or open
>> attachments unless you recognize the sender and know the content is safe.
>> 
>> 
>> 
>> 
>> Hi Anna-
>> 
>>> On Jan 10, 2020, at 5:34 PM, schumaker.anna@gmail.com wrote:
>>> 
>>> From: Anna Schumaker <Anna.Schumaker@Netapp.com>
>>> 
>>> There are some workloads where READ_PLUS might end up hurting
>>> performance,
>> 
>> Can you say more about this? Have you seen workloads that are
>> hurt by READ_PLUS? Nothing jumps out at me from the tables in
>> the cover letter.
> 
> It's mostly something I've seen when using btrfs in a virtual machine (so
> probably not a wide use case, and it's possible I need to change something in my
> setup to get it working better).
> 
>> 
>> 
>>> so let's be nice to users and provide a way to disable this
>>> operation similar to how READDIR_PLUS can be disabled.
>> 
>> Does it make sense to hold off on a mount option until there
>> is evidence that there is no other way to work around such a
>> performance regression?
>> 
>> - Attempt to address the regression directly
>> - Improve the heuristics about when READ_PLUS is used
>> - Document that dropping back to vers=4.1 will disable it
> 
> Yeah, we could hold off on the patch for now and see if anybody has any issues
> first.
> 
>> 
>> Any experience with NFS/RDMA?
> 
> Not yet, but I can try to test that next week.

Thanks for your response!


> Anna
> 
>> 
>> 
>>> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
>>> ---
>>> fs/nfs/fs_context.c       | 14 ++++++++++++++
>>> fs/nfs/nfs4client.c       |  3 +++
>>> include/linux/nfs_fs_sb.h |  1 +
>>> 3 files changed, 18 insertions(+)
>>> 
>>> diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
>>> index 0247dcb7b316..82ba07c7c1ce 100644
>>> --- a/fs/nfs/fs_context.c
>>> +++ b/fs/nfs/fs_context.c
>>> @@ -64,6 +64,7 @@ enum nfs_param {
>>>      Opt_proto,
>>>      Opt_rdirplus,
>>>      Opt_rdma,
>>> +     Opt_readplus,
>>>      Opt_resvport,
>>>      Opt_retrans,
>>>      Opt_retry,
>>> @@ -120,6 +121,7 @@ static const struct fs_parameter_spec nfs_param_specs[]
>>> = {
>>>      fsparam_string("proto",         Opt_proto),
>>>      fsparam_flag_no("rdirplus",     Opt_rdirplus),
>>>      fsparam_flag  ("rdma",          Opt_rdma),
>>> +     fsparam_flag_no("readplus",     Opt_readplus),
>>>      fsparam_flag_no("resvport",     Opt_resvport),
>>>      fsparam_u32   ("retrans",       Opt_retrans),
>>>      fsparam_string("retry",         Opt_retry),
>>> @@ -555,6 +557,12 @@ static int nfs_fs_context_parse_param(struct fs_context
>>> *fc,
>>>              else
>>>                      ctx->options |= NFS_OPTION_MIGRATION;
>>>              break;
>>> +     case Opt_readplus:
>>> +             if (result.negated)
>>> +                     ctx->options |= NFS_OPTION_NO_READ_PLUS;
>>> +             else
>>> +                     ctx->options &= ~NFS_OPTION_NO_READ_PLUS;
>>> +             break;
>>> 
>>>              /*
>>>               * options that take numeric values
>>> @@ -1176,6 +1184,10 @@ static int nfs_fs_context_validate(struct fs_context
>>> *fc)
>>>          (ctx->version != 4 || ctx->minorversion != 0))
>>>              goto out_migration_misuse;
>>> 
>>> +     if (ctx->options & NFS_OPTION_NO_READ_PLUS &&
>>> +         (ctx->version != 4 || ctx->minorversion < 2))
>>> +             goto out_noreadplus_misuse;
>>> +
>>>      /* Verify that any proto=/mountproto= options match the address
>>>       * families in the addr=/mountaddr= options.
>>>       */
>>> @@ -1254,6 +1266,8 @@ static int nfs_fs_context_validate(struct fs_context
>>> *fc)
>>>                        ctx->version, ctx->minorversion);
>>> out_migration_misuse:
>>>      return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS
>>> version");
>>> +out_noreadplus_misuse:
>>> +     return nfs_invalf(fc, "NFS: 'noreadplus' not supported for this NFS
>>> version\n");
>>> out_version_unavailable:
>>>      nfs_errorf(fc, "NFS: Version unavailable");
>>>      return ret;
>>> diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
>>> index 0cd767e5c977..868dc3c36ba1 100644
>>> --- a/fs/nfs/nfs4client.c
>>> +++ b/fs/nfs/nfs4client.c
>>> @@ -1016,6 +1016,9 @@ static int nfs4_server_common_setup(struct nfs_server
>>> *server,
>>>      server->caps |= server->nfs_client->cl_mvops->init_caps;
>>>      if (server->flags & NFS_MOUNT_NORDIRPLUS)
>>>                      server->caps &= ~NFS_CAP_READDIRPLUS;
>>> +     if (server->options & NFS_OPTION_NO_READ_PLUS)
>>> +             server->caps &= ~NFS_CAP_READ_PLUS;
>>> +
>>>      /*
>>>       * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
>>>       * authentication.
>>> diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
>>> index 11248c5a7b24..360e70c7bbb6 100644
>>> --- a/include/linux/nfs_fs_sb.h
>>> +++ b/include/linux/nfs_fs_sb.h
>>> @@ -172,6 +172,7 @@ struct nfs_server {
>>>      unsigned int            clone_blksize;  /* granularity of a CLONE
>>> operation */
>>> #define NFS_OPTION_FSCACHE    0x00000001      /* - local caching enabled */
>>> #define NFS_OPTION_MIGRATION  0x00000002      /* - NFSv4 migration enabled
>>> */
>>> +#define NFS_OPTION_NO_READ_PLUS      0x00000004      /* - NFSv4.2 READ_PLUS
>>> enabled */
>>> 
>>>      struct nfs_fsid         fsid;
>>>      __u64                   maxfilesize;    /* maximum file size */
>>> --
>>> 2.24.1
>>> 
>> 
>> --
>> Chuck Lever
>> 
>> 
>> 

--
Chuck Lever




^ permalink raw reply	[flat|nested] 11+ messages in thread

end of thread, back to index

Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-01-10 22:34 [PATCH 0/7] NFS: Add support for the v4.2 READ_PLUS operation schumaker.anna
2020-01-10 22:34 ` [PATCH 1/7] SUNRPC: Split out a function for setting current page schumaker.anna
2020-01-10 22:34 ` [PATCH 2/7] SUNRPC: Add the ability to expand holes in data pages schumaker.anna
2020-01-10 22:34 ` [PATCH 3/7] SUNRPC: Add the ability to shift data to a specific offset schumaker.anna
2020-01-10 22:34 ` [PATCH 4/7] NFS: Add READ_PLUS data segment support schumaker.anna
2020-01-10 22:34 ` [PATCH 5/7] NFS: Add READ_PLUS hole segment decoding schumaker.anna
2020-01-10 22:34 ` [PATCH 6/7] NFS: Decode multiple READ_PLUS segments schumaker.anna
2020-01-10 22:34 ` [PATCH 7/7] NFS: Add a mount option for READ_PLUS schumaker.anna
2020-01-10 22:41   ` Chuck Lever
2020-01-10 22:43     ` Schumaker, Anna
2020-01-10 22:45       ` Chuck Lever

Linux-NFS Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-nfs/0 linux-nfs/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-nfs linux-nfs/ https://lore.kernel.org/linux-nfs \
		linux-nfs@vger.kernel.org
	public-inbox-index linux-nfs

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-nfs


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git