linux-kernel - [RFC PATCH v1 17/18] block: export helper to get segment max size

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <3649c1dc673ea0a49a90f3e01b76ef91fb90f076.1719909395.git.leon@kernel.org>
Date: Tue,  2 Jul 2024 12:09:47 +0300
From: Leon Romanovsky <leon@...nel.org>
To: Jens Axboe <axboe@...nel.dk>,
	Jason Gunthorpe <jgg@...pe.ca>,
	Robin Murphy <robin.murphy@....com>,
	Joerg Roedel <joro@...tes.org>,
	Will Deacon <will@...nel.org>,
	Keith Busch <kbusch@...nel.org>,
	Christoph Hellwig <hch@....de>,
	"Zeng, Oak" <oak.zeng@...el.com>,
	Chaitanya Kulkarni <kch@...dia.com>
Cc: Sagi Grimberg <sagi@...mberg.me>,
	Bjorn Helgaas <bhelgaas@...gle.com>,
	Logan Gunthorpe <logang@...tatee.com>,
	Yishai Hadas <yishaih@...dia.com>,
	Shameer Kolothum <shameerali.kolothum.thodi@...wei.com>,
	Kevin Tian <kevin.tian@...el.com>,
	Alex Williamson <alex.williamson@...hat.com>,
	Marek Szyprowski <m.szyprowski@...sung.com>,
	Jérôme Glisse <jglisse@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-block@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-rdma@...r.kernel.org,
	iommu@...ts.linux.dev,
	linux-nvme@...ts.infradead.org,
	linux-pci@...r.kernel.org,
	kvm@...r.kernel.org,
	linux-mm@...ck.org
Subject: [RFC PATCH v1 17/18] block: export helper to get segment max size

From: Chaitanya Kulkarni <kch@...dia.com>

Export the get_max_segment_size() so driver can do use that to create
DMA mapping when it receives the request.

Signed-off-by: Chaitanya Kulkarni <kch@...dia.com>
Signed-off-by: Leon Romanovsky <leonro@...dia.com>
---
 block/blk-merge.c      | 3 ++-
 include/linux/blk-mq.h | 3 +++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/block/blk-merge.c b/block/blk-merge.c
index 8534c35e0497..0561e728ef95 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -190,7 +190,7 @@ static inline unsigned get_max_io_size(struct bio *bio,
  *
  * Returns the maximum number of bytes that can be added as a single segment.
  */
-static inline unsigned get_max_segment_size(const struct queue_limits *lim,
+inline unsigned get_max_segment_size(const struct queue_limits *lim,
 		struct page *start_page, unsigned long offset)
 {
 	unsigned long mask = lim->seg_boundary_mask;
@@ -203,6 +203,7 @@ static inline unsigned get_max_segment_size(const struct queue_limits *lim,
 	 */
 	return min(mask - offset, (unsigned long)lim->max_segment_size - 1) + 1;
 }
+EXPORT_SYMBOL_GPL(get_max_segment_size);
 
 /**
  * bvec_split_segs - verify whether or not a bvec should be split in the middle
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 89ba6b16fe8b..008c77c9b518 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -1150,4 +1150,7 @@ static inline int blk_rq_map_sg(struct request_queue *q, struct request *rq,
 }
 void blk_dump_rq_flags(struct request *, char *);
 
+unsigned get_max_segment_size(const struct queue_limits *lim,
+		struct page *start_page, unsigned long offset);
+
 #endif /* BLK_MQ_H */
-- 
2.45.2