Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1362344 > unrolled thread

[PATCH 1/8] block: move bvec iterator into include/linux/bvec_iter.h

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  [PATCH 1/8] block: move bvec iterator into include/linux/bvec_iter.h Ming Lei <ming.lei@canonical.com> - 2016-03-22 07:20 +0100
    Re: [PATCH 1/8] block: move bvec iterator into  include/linux/bvec_iter.h Christoph Hellwig <hch@infradead.org> - 2016-03-29 09:30 +0200
      Re: [PATCH 1/8] block: move bvec iterator into include/linux/bvec_iter.h Ming Lei <ming.lei@canonical.com> - 2016-03-29 11:00 +0200

#1362344 — [PATCH 1/8] block: move bvec iterator into include/linux/bvec_iter.h

bvec iterator helpers should be used to implement by
iterate_bvec():lib/iov_iter.c too, and move them into
one header, so that we can keep bvec iterator header
out of CONFIG_BLOCK. Then we can remove the inventing
of wheel in iterate_bvec().

Signed-off-by: Ming Lei <ming.lei@canonical.com>
---
 include/linux/bio.h       | 55 +--------------------------------
 include/linux/bvec_iter.h | 78 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 79 insertions(+), 54 deletions(-)
 create mode 100644 include/linux/bvec_iter.h

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 88bc64f..4abc129 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -31,6 +31,7 @@
 
 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
 #include <linux/blk_types.h>
+#include <linux/bvec_iter.h>
 
 #define BIO_DEBUG
 
@@ -40,10 +41,6 @@
 #define BIO_BUG_ON
 #endif
 
-#define BIO_MAX_PAGES		256
-#define BIO_MAX_SIZE		(BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
-#define BIO_MAX_SECTORS		(BIO_MAX_SIZE >> 9)
-
 /*
  * upper 16 bits of bi_rw define the io priority of this bio
  */
@@ -57,29 +54,6 @@
 	(bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT);	\
 } while (0)
 
-/*
- * various member access, note that bio_data should of course not be used
- * on highmem page vectors
- */
-#define __bvec_iter_bvec(bvec, iter)	(&(bvec)[(iter).bi_idx])
-
-#define bvec_iter_page(bvec, iter)				\
-	(__bvec_iter_bvec((bvec), (iter))->bv_page)
-
-#define 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)				\
-	(__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
-
-#define bvec_iter_bvec(bvec, iter)				\
-((struct bio_vec) {						\
-	.bv_page	= bvec_iter_page((bvec), (iter)),	\
-	.bv_len		= bvec_iter_len((bvec), (iter)),	\
-	.bv_offset	= bvec_iter_offset((bvec), (iter)),	\
-})
-
 #define bio_iter_iovec(bio, iter)				\
 	bvec_iter_bvec((bio)->bi_io_vec, (iter))
 
@@ -193,33 +167,6 @@ static inline void *bio_data(struct bio *bio)
 #define bio_for_each_segment_all(bvl, bio, i)				\
 	for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
 
-static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
-				     unsigned bytes)
-{
-	WARN_ONCE(bytes > iter->bi_size,
-		  "Attempted to advance past end of bvec iter\n");
-
-	while (bytes) {
-		unsigned len = min(bytes, bvec_iter_len(bv, *iter));
-
-		bytes -= len;
-		iter->bi_size -= len;
-		iter->bi_bvec_done += len;
-
-		if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
-			iter->bi_bvec_done = 0;
-			iter->bi_idx++;
-		}
-	}
-}
-
-#define for_each_bvec(bvl, bio_vec, iter, start)			\
-	for (iter = (start);						\
-	     (iter).bi_size &&						\
-		((bvl = bvec_iter_bvec((bio_vec), (iter))), 1);	\
-	     bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
-
-
 static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
 				    unsigned bytes)
 {
diff --git a/include/linux/bvec_iter.h b/include/linux/bvec_iter.h
new file mode 100644
index 0000000..cc43055
--- /dev/null
+++ b/include/linux/bvec_iter.h
@@ -0,0 +1,78 @@
+/*
+ * bvec iterator
+ *
+ * Copyright (C) 2001 Ming Lei <ming.lei@canonical.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public Licens
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
+ */
+#ifndef __LINUX_BVEC_ITER_H
+#define __LINUX_BVEC_ITER_H
+
+#include <linux/blk_types.h>
+
+#define BIO_MAX_PAGES		256
+#define BIO_MAX_SIZE		(BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
+#define BIO_MAX_SECTORS		(BIO_MAX_SIZE >> 9)
+
+/*
+ * various member access, note that bio_data should of course not be used
+ * on highmem page vectors
+ */
+#define __bvec_iter_bvec(bvec, iter)	(&(bvec)[(iter).bi_idx])
+
+#define bvec_iter_page(bvec, iter)				\
+	(__bvec_iter_bvec((bvec), (iter))->bv_page)
+
+#define 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)				\
+	(__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
+
+#define bvec_iter_bvec(bvec, iter)				\
+((struct bio_vec) {						\
+	.bv_page	= bvec_iter_page((bvec), (iter)),	\
+	.bv_len		= bvec_iter_len((bvec), (iter)),	\
+	.bv_offset	= bvec_iter_offset((bvec), (iter)),	\
+})
+
+static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
+				     unsigned bytes)
+{
+	WARN_ONCE(bytes > iter->bi_size,
+		  "Attempted to advance past end of bvec iter\n");
+
+	while (bytes) {
+		unsigned len = min(bytes, bvec_iter_len(bv, *iter));
+
+		bytes -= len;
+		iter->bi_size -= len;
+		iter->bi_bvec_done += len;
+
+		if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
+			iter->bi_bvec_done = 0;
+			iter->bi_idx++;
+		}
+	}
+}
+
+#define for_each_bvec(bvl, bio_vec, iter, start)			\
+	for (iter = (start);						\
+	     (iter).bi_size &&						\
+		((bvl = bvec_iter_bvec((bio_vec), (iter))), 1);	\
+	     bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
+
+#endif /* __LINUX_BVEC_ITER_H */
-- 
1.9.1

[toc] | [next] | [standalone]

#1365938 — Re: [PATCH 1/8] block: move bvec iterator into include/linux/bvec_iter.h

> --- a/include/linux/bio.h
> +++ b/include/linux/bio.h
> @@ -31,6 +31,7 @@
>  
>  /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
>  #include <linux/blk_types.h>
> +#include <linux/bvec_iter.h>
>  
>  #define BIO_DEBUG
>  
> @@ -40,10 +41,6 @@
>  #define BIO_BUG_ON
>  #endif
>  
> -#define BIO_MAX_PAGES		256
> -#define BIO_MAX_SIZE		(BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
> -#define BIO_MAX_SECTORS		(BIO_MAX_SIZE >> 9)

I see no reason why these should be moved out of bio.h.

Otherwise this looks fine to me.

[toc] | [prev] | [next] | [standalone]

#1366021

On Tue, Mar 29, 2016 at 3:26 PM, Christoph Hellwig <hch@infradead.org> wrote:
>> --- a/include/linux/bio.h
>> +++ b/include/linux/bio.h
>> @@ -31,6 +31,7 @@
>>
>>  /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
>>  #include <linux/blk_types.h>
>> +#include <linux/bvec_iter.h>
>>
>>  #define BIO_DEBUG
>>
>> @@ -40,10 +41,6 @@
>>  #define BIO_BUG_ON
>>  #endif
>>
>> -#define BIO_MAX_PAGES                256
>> -#define BIO_MAX_SIZE         (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
>> -#define BIO_MAX_SECTORS              (BIO_MAX_SIZE >> 9)
>
> I see no reason why these should be moved out of bio.h.

You are right, these should be kept in bio.h.

Thanks for your review!

>
> Otherwise this looks fine to me.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-block" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web