From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
From: Ming Lei <tom.leiming@gmail.com>
To: Jens Axboe <axboe@fb.com>, linux-kernel@vger.kernel.org
Cc: linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Christoph Hellwig <hch@infradead.org>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Ming Lei <tom.leiming@gmail.com>,
        Mike Christie <mchristi@redhat.com>,
        Hannes Reinecke <hare@suse.com>,
        Keith Busch <keith.busch@intel.com>,
        Mike Snitzer <snitzer@redhat.com>
Subject: [PATCH 27/60] block: introduce BIO_SP_MAX_SECTORS
Date: Sat, 29 Oct 2016 16:08:26 +0800
Message-Id: <1477728600-12938-28-git-send-email-tom.leiming@gmail.com>
In-Reply-To: <1477728600-12938-1-git-send-email-tom.leiming@gmail.com>
References: <1477728600-12938-1-git-send-email-tom.leiming@gmail.com>
Sender: linux-kernel-owner@vger.kernel.org
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This macro is needed when one multipage bvec based bio is
converted to singlepage bvec based bio, for example, bio bounce
requires singlepage bvec.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
---
 include/linux/bio.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 8634bd24984c..fa71f6a57f81 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -40,6 +40,9 @@
 
 #define BIO_MAX_PAGES		256
 
+/* Max sectors of bio with singlepage bvec */
+#define BIO_SP_MAX_SECTORS     (BIO_MAX_PAGES * (PAGE_SIZE >> 9))
+
 #define bio_prio(bio)			(bio)->bi_ioprio
 #define bio_set_prio(bio, prio)		((bio)->bi_ioprio = prio)
 
-- 
2.7.4