diff options
author | Heinz Mauelshagen <hjm@redhat.com> | 2007-05-09 09:33:01 (GMT) |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-05-09 19:30:47 (GMT) |
commit | c8b03afe3d38a635861e4bfa5c563d844e754a91 (patch) | |
tree | d23d2aa8d6cec93bab6e23ffd2199509e7d85113 /drivers/md/dm-io.h | |
parent | 891ce207011d3d9219f79fd5114c8594bbacc653 (diff) | |
download | linux-fsl-qoriq-c8b03afe3d38a635861e4bfa5c563d844e754a91.tar.xz |
dm io: new interface
Add a new API to dm-io.c that uses a private mempool and bio_set for each
client.
The new functions to use are dm_io_client_create(), dm_io_client_destroy(),
dm_io_client_resize() and dm_io().
Signed-off-by: Heinz Mauelshagen <hjm@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Milan Broz <mbroz@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/md/dm-io.h')
-rw-r--r-- | drivers/md/dm-io.h | 52 |
1 files changed, 51 insertions, 1 deletions
diff --git a/drivers/md/dm-io.h b/drivers/md/dm-io.h index f9035bf..05b1338 100644 --- a/drivers/md/dm-io.h +++ b/drivers/md/dm-io.h @@ -20,13 +20,47 @@ struct page_list { struct page *page; }; - /* * 'error' is a bitset, with each bit indicating whether an error * occurred doing io to the corresponding region. */ typedef void (*io_notify_fn)(unsigned long error, void *context); +enum dm_io_mem_type { + DM_IO_PAGE_LIST,/* Page list */ + DM_IO_BVEC, /* Bio vector */ + DM_IO_VMA, /* Virtual memory area */ + DM_IO_KMEM, /* Kernel memory */ +}; + +struct dm_io_memory { + enum dm_io_mem_type type; + + union { + struct page_list *pl; + struct bio_vec *bvec; + void *vma; + void *addr; + } ptr; + + unsigned offset; +}; + +struct dm_io_notify { + io_notify_fn fn; /* Callback for asynchronous requests */ + void *context; /* Passed to callback */ +}; + +/* + * IO request structure + */ +struct dm_io_client; +struct dm_io_request { + int bi_rw; /* READ|WRITE - not READA */ + struct dm_io_memory mem; /* Memory to use for io */ + struct dm_io_notify notify; /* Synchronous if notify.fn is NULL */ + struct dm_io_client *client; /* Client memory handler */ +}; /* * Before anyone uses the IO interface they should call @@ -39,6 +73,16 @@ int dm_io_get(unsigned int num_pages); void dm_io_put(unsigned int num_pages); /* + * For async io calls, users can alternatively use the dm_io() function below + * and dm_io_client_create() to create private mempools for the client. + * + * Create/destroy may block. + */ +struct dm_io_client *dm_io_client_create(unsigned num_pages); +int dm_io_client_resize(unsigned num_pages, struct dm_io_client *client); +void dm_io_client_destroy(struct dm_io_client *client); + +/* * Synchronous IO. * * Please ensure that the rw flag in the next two functions is @@ -71,4 +115,10 @@ int dm_io_async_bvec(unsigned int num_regions, struct io_region *where, int rw, int dm_io_async_vm(unsigned int num_regions, struct io_region *where, int rw, void *data, io_notify_fn fn, void *context); +/* + * IO interface using private per-client pools. + */ +int dm_io(struct dm_io_request *io_req, unsigned num_regions, + struct io_region *region, unsigned long *sync_error_bits); + #endif |