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authorLinus Torvalds <torvalds@linux-foundation.org>2018-04-05 14:27:02 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-04-05 14:27:02 -0700
commit3526dd0c7832f1011a0477cc6d903662bae05ea8 (patch)
tree22fbac64eb40a0b29bfa4c029695f39b2f591e62 /include/linux/scatterlist.h
parentdd972f924df6bdbc0ab185a38d5d2361dbc26311 (diff)
parentbc6d65e6dc89c3b7ff78e4ad797117c122ffde8e (diff)
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Merge tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe: "It's a pretty quiet round this time, which is nice. This contains: - series from Bart, cleaning up the way we set/test/clear atomic queue flags. - series from Bart, fixing races between gendisk and queue registration and removal. - set of bcache fixes and improvements from various folks, by way of Michael Lyle. - set of lightnvm updates from Matias, most of it being the 1.2 to 2.0 transition. - removal of unused DIO flags from Nikolay. - blk-mq/sbitmap memory ordering fixes from Omar. - divide-by-zero fix for BFQ from Paolo. - minor documentation patches from Randy. - timeout fix from Tejun. - Alpha "can't write a char atomically" fix from Mikulas. - set of NVMe fixes by way of Keith. - bsg and bsg-lib improvements from Christoph. - a few sed-opal fixes from Jonas. - cdrom check-disk-change deadlock fix from Maurizio. - various little fixes, comment fixes, etc from various folks" * tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block: (139 commits) blk-mq: Directly schedule q->timeout_work when aborting a request blktrace: fix comment in blktrace_api.h lightnvm: remove function name in strings lightnvm: pblk: remove some unnecessary NULL checks lightnvm: pblk: don't recover unwritten lines lightnvm: pblk: implement 2.0 support lightnvm: pblk: implement get log report chunk lightnvm: pblk: rename ppaf* to addrf* lightnvm: pblk: check for supported version lightnvm: implement get log report chunk helpers lightnvm: make address conversions depend on generic device lightnvm: add support for 2.0 address format lightnvm: normalize geometry nomenclature lightnvm: complete geo structure with maxoc* lightnvm: add shorten OCSSD version in geo lightnvm: add minor version to generic geometry lightnvm: simplify geometry structure lightnvm: pblk: refactor init/exit sequences lightnvm: Avoid validation of default op value lightnvm: centralize permission check for lightnvm ioctl ...
Diffstat (limited to 'include/linux/scatterlist.h')
-rw-r--r--include/linux/scatterlist.h23
1 files changed, 13 insertions, 10 deletions
diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h
index aa5d4eb725f5..51f52020ad5f 100644
--- a/include/linux/scatterlist.h
+++ b/include/linux/scatterlist.h
@@ -65,16 +65,18 @@ struct sg_table {
*/
#define SG_MAGIC 0x87654321
+#define SG_CHAIN 0x01UL
+#define SG_END 0x02UL
/*
* We overload the LSB of the page pointer to indicate whether it's
* a valid sg entry, or whether it points to the start of a new scatterlist.
* Those low bits are there for everyone! (thanks mason :-)
*/
-#define sg_is_chain(sg) ((sg)->page_link & 0x01)
-#define sg_is_last(sg) ((sg)->page_link & 0x02)
+#define sg_is_chain(sg) ((sg)->page_link & SG_CHAIN)
+#define sg_is_last(sg) ((sg)->page_link & SG_END)
#define sg_chain_ptr(sg) \
- ((struct scatterlist *) ((sg)->page_link & ~0x03))
+ ((struct scatterlist *) ((sg)->page_link & ~(SG_CHAIN | SG_END)))
/**
* sg_assign_page - Assign a given page to an SG entry
@@ -88,13 +90,13 @@ struct sg_table {
**/
static inline void sg_assign_page(struct scatterlist *sg, struct page *page)
{
- unsigned long page_link = sg->page_link & 0x3;
+ unsigned long page_link = sg->page_link & (SG_CHAIN | SG_END);
/*
* In order for the low bit stealing approach to work, pages
* must be aligned at a 32-bit boundary as a minimum.
*/
- BUG_ON((unsigned long) page & 0x03);
+ BUG_ON((unsigned long) page & (SG_CHAIN | SG_END));
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
BUG_ON(sg_is_chain(sg));
@@ -130,7 +132,7 @@ static inline struct page *sg_page(struct scatterlist *sg)
BUG_ON(sg->sg_magic != SG_MAGIC);
BUG_ON(sg_is_chain(sg));
#endif
- return (struct page *)((sg)->page_link & ~0x3);
+ return (struct page *)((sg)->page_link & ~(SG_CHAIN | SG_END));
}
/**
@@ -178,7 +180,8 @@ static inline void sg_chain(struct scatterlist *prv, unsigned int prv_nents,
* Set lowest bit to indicate a link pointer, and make sure to clear
* the termination bit if it happens to be set.
*/
- prv[prv_nents - 1].page_link = ((unsigned long) sgl | 0x01) & ~0x02;
+ prv[prv_nents - 1].page_link = ((unsigned long) sgl | SG_CHAIN)
+ & ~SG_END;
}
/**
@@ -198,8 +201,8 @@ static inline void sg_mark_end(struct scatterlist *sg)
/*
* Set termination bit, clear potential chain bit
*/
- sg->page_link |= 0x02;
- sg->page_link &= ~0x01;
+ sg->page_link |= SG_END;
+ sg->page_link &= ~SG_CHAIN;
}
/**
@@ -215,7 +218,7 @@ static inline void sg_unmark_end(struct scatterlist *sg)
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
#endif
- sg->page_link &= ~0x02;
+ sg->page_link &= ~SG_END;
}
/**