linux-kernel - [RFC PATCH 14/16] block: bio: go straight from pfn

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]

Date:   Wed, 24 May 2017 15:42:25 -0600
From:   Logan Gunthorpe <logang@...tatee.com>
To:     linux-kernel@...r.kernel.org, linux-block@...r.kernel.org,
        linux-nvdimm@...ts.01.org, linux-nvme@...ts.infradead.org,
        linux-rdma@...r.kernel.org
Cc:     Christoph Hellwig <hch@....de>,
        Jason Gunthorpe <jgunthorpe@...idianresearch.com>,
        Jens Axboe <axboe@...nel.dk>,
        Dan Williams <dan.j.williams@...el.com>,
        Ross Zwisler <ross.zwisler@...ux.intel.com>,
        Matthew Wilcox <mawilcox@...rosoft.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Ming Lei <ming.lei@...onical.com>,
        Johannes Berg <johannes.berg@...el.com>,
        Stephen Bates <sbates@...thlin.com>,
        Sagi Grimberg <sagi@...mberg.me>,
        Keith Busch <keith.busch@...el.com>,
        Christian König <christian.koenig@....com>,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Jerome Glisse <jglisse@...hat.com>,
        Logan Gunthorpe <logang@...tatee.com>
Subject: [RFC PATCH 14/16] block: bio: go straight from pfn_t to phys instead of through page

Going straight from pfn_t to physical address is cheaper and
avoids the potential BUG_ON in bvec_page for unmappable memory.

Signed-off-by: Logan Gunthorpe <logang@...tatee.com>
Signed-off-by: Stephen Bates <sbates@...thlin.com>
---
 include/linux/bio.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/include/linux/bio.h b/include/linux/bio.h
index bc5f5d3..890c94d 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -46,6 +46,8 @@
 #define bio_iter_iovec(bio, iter)				\
 	bvec_iter_bvec((bio)->bi_io_vec, (iter))
 
+#define bio_iter_pfn_t(bio, iter)				\
+	bvec_iter_pfn_t((bio)->bi_io_vec, (iter))
 #define bio_iter_page(bio, iter)				\
 	bvec_iter_page((bio)->bi_io_vec, (iter))
 #define bio_iter_len(bio, iter)					\
@@ -53,6 +55,7 @@
 #define bio_iter_offset(bio, iter)				\
 	bvec_iter_offset((bio)->bi_io_vec, (iter))
 
+#define bio_pfn_t(bio)		bio_iter_pfn_t((bio), (bio)->bi_iter)
 #define bio_page(bio)		bio_iter_page((bio), (bio)->bi_iter)
 #define bio_offset(bio)		bio_iter_offset((bio), (bio)->bi_iter)
 #define bio_iovec(bio)		bio_iter_iovec((bio), (bio)->bi_iter)
@@ -118,8 +121,8 @@ static inline void *bio_data(struct bio *bio)
 /*
  * will die
  */
-#define bio_to_phys(bio)	(page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
-#define bvec_to_phys(bv)	(page_to_phys(bvec_page((bv))) + (unsigned long) (bv)->bv_offset)
+#define bio_to_phys(bio)	(pfn_t_to_phys(bio_pfn_t((bio))) + (unsigned long) bio_offset((bio)))
+#define bvec_to_phys(bv)	(pfn_t_to_phys((bv)->bv_pfn) + (unsigned long) (bv)->bv_offset)
 
 /*
  * queues that have highmem support enabled may still need to revert to
-- 
2.1.4