| Message ID | 1337182230-11839-1-git-send-email-saugata.das@stericsson.com |
|---|---|
| State | Superseded, archived |
| Headers | show |
Hi Group, Will you please provide some feedback on the following RFC patches, [RFC 1/3] block: Context support [RFC 2/3] ext4: Context support Regards Saugata On 16 May 2012 21:00, Saugata Das <saugata.das@stericsson.com> wrote: > From: Saugata Das <saugata.das@linaro.org> > > On eMMC and UFS devices there is a new feature of setting context with each > read or write. The idea is to classify the data from different files and > apply the realibility on the complete file instead of individual writes, > which helps in performance. A new address space operation has been a added > to get the context from file system and set up the bi_context field in bio. > Then we need to ensure that bio from different contexts are not merged. The > context is then passed to the underlying driver as part of the read or write > request. Since the number of MMC contexts is limited, multiple file system > contexts are mapped to single MMC context. > > Signed-off-by: Saugata Das <saugata.das@linaro.org> > --- > block/blk-core.c | 1 + > block/blk-merge.c | 3 +++ > fs/mpage.c | 12 ++++++++++++ > include/linux/blk_types.h | 1 + > include/linux/blkdev.h | 1 + > include/linux/buffer_head.h | 2 ++ > include/linux/fs.h | 1 + > 7 files changed, 21 insertions(+), 0 deletions(-) > > diff --git a/block/blk-core.c b/block/blk-core.c > index 1f61b74..274e05d 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -1309,6 +1309,7 @@ void init_request_from_bio(struct request *req, struct bio *bio) > req->errors = 0; > req->__sector = bio->bi_sector; > req->ioprio = bio_prio(bio); > + req->context = bio->bi_context; > blk_rq_bio_prep(req->q, req, bio); > } > > diff --git a/block/blk-merge.c b/block/blk-merge.c > index 160035f..ed70d56 100644 > --- a/block/blk-merge.c > +++ b/block/blk-merge.c > @@ -497,6 +497,9 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) > if (bio_integrity(bio) != blk_integrity_rq(rq)) > return false; > > + if (bio->bi_context != rq->bio->bi_context) > + return false; > + > return true; > } > > diff --git a/fs/mpage.c b/fs/mpage.c > index 0face1c..4889842 100644 > --- a/fs/mpage.c > +++ b/fs/mpage.c > @@ -293,6 +293,12 @@ alloc_new: > goto confused; > } > > + if (page && page->mapping && page->mapping->a_ops && > + page->mapping->a_ops->get_context) > + bio->bi_context = page->mapping->a_ops->get_context(page); > + else > + bio->bi_context = 0; > + > length = first_hole << blkbits; > if (bio_add_page(bio, page, length, 0) < length) { > bio = mpage_bio_submit(READ, bio); > @@ -581,6 +587,12 @@ alloc_new: > goto confused; > } > > + if (page && page->mapping && page->mapping->a_ops && > + page->mapping->a_ops->get_context) > + bio->bi_context = page->mapping->a_ops->get_context(page); > + else > + bio->bi_context = 0; > + > /* > * Must try to add the page before marking the buffer clean or > * the confused fail path above (OOM) will be very confused when > diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h > index 4053cbd..f3ac448 100644 > --- a/include/linux/blk_types.h > +++ b/include/linux/blk_types.h > @@ -42,6 +42,7 @@ struct bio { > > unsigned short bi_vcnt; /* how many bio_vec's */ > unsigned short bi_idx; /* current index into bvl_vec */ > + unsigned long bi_context; /* context of this bio */ > > /* Number of segments in this BIO after > * physical address coalescing is performed. > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index 2aa2466..0dd9a08 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -167,6 +167,7 @@ struct request { > struct list_head timeout_list; > unsigned int timeout; > int retries; > + unsigned long context; /* context of this request */ > > /* > * completion callback. > diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h > index 13bba17..0776564 100644 > --- a/include/linux/buffer_head.h > +++ b/include/linux/buffer_head.h > @@ -72,6 +72,8 @@ struct buffer_head { > struct list_head b_assoc_buffers; /* associated with another mapping */ > struct address_space *b_assoc_map; /* mapping this buffer is > associated with */ > + unsigned long b_context; /* context for this buffer within the > + storage device */ > atomic_t b_count; /* users using this buffer_head */ > }; > > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 8de6755..4b379d8 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -626,6 +626,7 @@ struct address_space_operations { > int (*is_partially_uptodate) (struct page *, read_descriptor_t *, > unsigned long); > int (*error_remove_page)(struct address_space *, struct page *); > + int (*get_context)(struct page *); > }; > > extern const struct address_space_operations empty_aops; > -- > 1.7.4.3 > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/block/blk-core.c b/block/blk-core.c index 1f61b74..274e05d 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1309,6 +1309,7 @@ void init_request_from_bio(struct request *req, struct bio *bio) req->errors = 0; req->__sector = bio->bi_sector; req->ioprio = bio_prio(bio); + req->context = bio->bi_context; blk_rq_bio_prep(req->q, req, bio); } diff --git a/block/blk-merge.c b/block/blk-merge.c index 160035f..ed70d56 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -497,6 +497,9 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) if (bio_integrity(bio) != blk_integrity_rq(rq)) return false; + if (bio->bi_context != rq->bio->bi_context) + return false; + return true; } diff --git a/fs/mpage.c b/fs/mpage.c index 0face1c..4889842 100644 --- a/fs/mpage.c +++ b/fs/mpage.c @@ -293,6 +293,12 @@ alloc_new: goto confused; } + if (page && page->mapping && page->mapping->a_ops && + page->mapping->a_ops->get_context) + bio->bi_context = page->mapping->a_ops->get_context(page); + else + bio->bi_context = 0; + length = first_hole << blkbits; if (bio_add_page(bio, page, length, 0) < length) { bio = mpage_bio_submit(READ, bio); @@ -581,6 +587,12 @@ alloc_new: goto confused; } + if (page && page->mapping && page->mapping->a_ops && + page->mapping->a_ops->get_context) + bio->bi_context = page->mapping->a_ops->get_context(page); + else + bio->bi_context = 0; + /* * Must try to add the page before marking the buffer clean or * the confused fail path above (OOM) will be very confused when diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 4053cbd..f3ac448 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -42,6 +42,7 @@ struct bio { unsigned short bi_vcnt; /* how many bio_vec's */ unsigned short bi_idx; /* current index into bvl_vec */ + unsigned long bi_context; /* context of this bio */ /* Number of segments in this BIO after * physical address coalescing is performed. diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 2aa2466..0dd9a08 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -167,6 +167,7 @@ struct request { struct list_head timeout_list; unsigned int timeout; int retries; + unsigned long context; /* context of this request */ /* * completion callback. diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index 13bba17..0776564 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -72,6 +72,8 @@ struct buffer_head { struct list_head b_assoc_buffers; /* associated with another mapping */ struct address_space *b_assoc_map; /* mapping this buffer is associated with */ + unsigned long b_context; /* context for this buffer within the + storage device */ atomic_t b_count; /* users using this buffer_head */ }; diff --git a/include/linux/fs.h b/include/linux/fs.h index 8de6755..4b379d8 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -626,6 +626,7 @@ struct address_space_operations { int (*is_partially_uptodate) (struct page *, read_descriptor_t *, unsigned long); int (*error_remove_page)(struct address_space *, struct page *); + int (*get_context)(struct page *); }; extern const struct address_space_operations empty_aops;