4.14-stable patches

added patches:
	block-introduce-multi-page-bvec-helpers.patch

diff --git a/queue-4.14/block-introduce-multi-page-bvec-helpers.patch b/queue-4.14/block-introduce-multi-page-bvec-helpers.patch
new file mode 100644 (file)
index 0000000..6377e92
--- /dev/null
+++ b/queue-4.14/block-introduce-multi-page-bvec-helpers.patch
@@ -0,0 +1,113 @@
+From 3d75ca0adef4280650c6690a0c4702a74a6f3c95 Mon Sep 17 00:00:00 2001
+From: Ming Lei <ming.lei@redhat.com>
+Date: Fri, 15 Feb 2019 19:13:10 +0800
+Subject: block: introduce multi-page bvec helpers
+
+From: Ming Lei <ming.lei@redhat.com>
+
+commit 3d75ca0adef4280650c6690a0c4702a74a6f3c95 upstream.
+
+This patch introduces helpers of 'mp_bvec_iter_*' for multi-page bvec
+support.
+
+The introduced helpers treate one bvec as real multi-page segment,
+which may include more than one pages.
+
+The existed helpers of bvec_iter_* are interfaces for supporting current
+bvec iterator which is thought as single-page by drivers, fs, dm and
+etc. These introduced helpers will build single-page bvec in flight, so
+this way won't break current bio/bvec users, which needn't any change.
+
+Follows some multi-page bvec background:
+
+- bvecs stored in bio->bi_io_vec is always multi-page style
+
+- bvec(struct bio_vec) represents one physically contiguous I/O
+  buffer, now the buffer may include more than one page after
+  multi-page bvec is supported, and all these pages represented
+  by one bvec is physically contiguous. Before multi-page bvec
+  support, at most one page is included in one bvec, we call it
+  single-page bvec.
+
+- .bv_page of the bvec points to the 1st page in the multi-page bvec
+
+- .bv_offset of the bvec is the offset of the buffer in the bvec
+
+The effect on the current drivers/filesystem/dm/bcache/...:
+
+- almost everyone supposes that one bvec only includes one single
+  page, so we keep the sp interface not changed, for example,
+  bio_for_each_segment() still returns single-page bvec
+
+- bio_for_each_segment_all() will return single-page bvec too
+
+- during iterating, iterator variable(struct bvec_iter) is always
+  updated in multi-page bvec style, and bvec_iter_advance() is kept
+  not changed
+
+- returned(copied) single-page bvec is built in flight by bvec
+  helpers from the stored multi-page bvec
+
+Reviewed-by: Christoph Hellwig <hch@lst.de>
+Reviewed-by: Omar Sandoval <osandov@fb.com>
+Signed-off-by: Ming Lei <ming.lei@redhat.com>
+Signed-off-by: Jens Axboe <axboe@kernel.dk>
+Cc: Zubin Mithra <zsm@chromium.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/linux/bvec.h |   30 +++++++++++++++++++++++++++---
+ 1 file changed, 27 insertions(+), 3 deletions(-)
+
+--- a/include/linux/bvec.h
++++ b/include/linux/bvec.h
+@@ -23,6 +23,7 @@
+ #include <linux/kernel.h>
+ #include <linux/bug.h>
+ #include <linux/errno.h>
++#include <linux/mm.h>
+ 
+ /*
+  * was unsigned short, but we might as well be ready for > 64kB I/O pages
+@@ -52,16 +53,39 @@ struct bvec_iter {
+  */
+ #define __bvec_iter_bvec(bvec, iter)  (&(bvec)[(iter).bi_idx])
+ 
+-#define bvec_iter_page(bvec, iter)                            \
++/* multi-page (mp_bvec) helpers */
++#define mp_bvec_iter_page(bvec, iter)                         \
+       (__bvec_iter_bvec((bvec), (iter))->bv_page)
+ 
+-#define bvec_iter_len(bvec, iter)                             \
++#define mp_bvec_iter_len(bvec, iter)                          \
+       min((iter).bi_size,                                     \
+           __bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done)
+ 
+-#define bvec_iter_offset(bvec, iter)                          \
++#define mp_bvec_iter_offset(bvec, iter)                               \
+       (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
+ 
++#define mp_bvec_iter_page_idx(bvec, iter)                     \
++      (mp_bvec_iter_offset((bvec), (iter)) / PAGE_SIZE)
++
++#define mp_bvec_iter_bvec(bvec, iter)                         \
++((struct bio_vec) {                                           \
++      .bv_page        = mp_bvec_iter_page((bvec), (iter)),    \
++      .bv_len         = mp_bvec_iter_len((bvec), (iter)),     \
++      .bv_offset      = mp_bvec_iter_offset((bvec), (iter)),  \
++})
++
++/* For building single-page bvec in flight */
++ #define bvec_iter_offset(bvec, iter)                         \
++      (mp_bvec_iter_offset((bvec), (iter)) % PAGE_SIZE)
++
++#define bvec_iter_len(bvec, iter)                             \
++      min_t(unsigned, mp_bvec_iter_len((bvec), (iter)),               \
++            PAGE_SIZE - bvec_iter_offset((bvec), (iter)))
++
++#define bvec_iter_page(bvec, iter)                            \
++      nth_page(mp_bvec_iter_page((bvec), (iter)),             \
++               mp_bvec_iter_page_idx((bvec), (iter)))
++
+ #define bvec_iter_bvec(bvec, iter)                            \
+ ((struct bio_vec) {                                           \
+       .bv_page        = bvec_iter_page((bvec), (iter)),       \

diff --git a/queue-4.14/series b/queue-4.14/series
index 06594d7464e6ab691cab2a916bbbf338119d25a2..24cd4dad08668ef1f8e1289927c161b24c69fb36 100644 (file)
--- a/queue-4.14/series
+++ b/queue-4.14/series
@@ -5,3 +5,4 @@ arch-pgtable-define-max_possible_physmem_bits-where-needed.patch
 arm-9120-1-revert-amba-make-use-of-1-irqs-warn.patch
 ib-qib-use-struct_size-helper.patch
 ib-qib-protect-from-buffer-overflow-in-struct-qib_user_sdma_pkt-fields.patch
+block-introduce-multi-page-bvec-helpers.patch