diff options
Diffstat (limited to 'drivers/md/dm-io.c')
| -rw-r--r-- | drivers/md/dm-io.c | 61 |
1 files changed, 44 insertions, 17 deletions
diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c index 4d19c45158b..66db79208c1 100644 --- a/drivers/md/dm-io.c +++ b/drivers/md/dm-io.c @@ -1,5 +1,6 @@ /* * Copyright (C) 2003 Sistina Software + * Copyright (C) 2006 Red Hat GmbH * * This file is released under the GPL. */ @@ -14,11 +15,17 @@ static struct bio_set *_bios; +struct dm_io_client { + mempool_t *pool; + struct bio_set *bios; +}; + /* FIXME: can we shrink this ? */ struct io { unsigned long error; atomic_t count; struct task_struct *sleeper; + struct dm_io_client *client; io_notify_fn callback; void *context; }; @@ -26,12 +33,24 @@ struct io { /* * io contexts are only dynamically allocated for asynchronous * io. Since async io is likely to be the majority of io we'll - * have the same number of io contexts as buffer heads ! (FIXME: - * must reduce this). + * have the same number of io contexts as bios! (FIXME: must reduce this). */ static unsigned _num_ios; static mempool_t *_io_pool; +/* + * Temporary functions to allow old and new interfaces to co-exist. + */ +static struct bio_set *bios(struct dm_io_client *client) +{ + return client ? client->bios : _bios; +} + +static mempool_t *io_pool(struct dm_io_client *client) +{ + return client ? client->pool : _io_pool; +} + static unsigned int pages_to_ios(unsigned int pages) { return 4 * pages; /* too many ? */ @@ -118,7 +137,7 @@ static void dec_count(struct io *io, unsigned int region, int error) io_notify_fn fn = io->callback; void *context = io->context; - mempool_free(io, _io_pool); + mempool_free(io, io_pool(io->client)); fn(r, context); } } @@ -241,7 +260,9 @@ static void vm_dp_init(struct dpages *dp, void *data) static void dm_bio_destructor(struct bio *bio) { - bio_free(bio, _bios); + struct io *io = bio->bi_private; + + bio_free(bio, bios(io->client)); } /*----------------------------------------------------------------- @@ -264,7 +285,7 @@ static void do_region(int rw, unsigned int region, struct io_region *where, * to hide it from bio_add_page(). */ num_bvecs = (remaining / (PAGE_SIZE >> SECTOR_SHIFT)) + 2; - bio = bio_alloc_bioset(GFP_NOIO, num_bvecs, _bios); + bio = bio_alloc_bioset(GFP_NOIO, num_bvecs, bios(io->client)); bio->bi_sector = where->sector + (where->count - remaining); bio->bi_bdev = where->bdev; bio->bi_end_io = endio; @@ -319,8 +340,9 @@ static void dispatch_io(int rw, unsigned int num_regions, dec_count(io, 0, 0); } -static int sync_io(unsigned int num_regions, struct io_region *where, - int rw, struct dpages *dp, unsigned long *error_bits) +static int sync_io(struct dm_io_client *client, unsigned int num_regions, + struct io_region *where, int rw, struct dpages *dp, + unsigned long *error_bits) { struct io io; @@ -332,6 +354,7 @@ static int sync_io(unsigned int num_regions, struct io_region *where, io.error = 0; atomic_set(&io.count, 1); /* see dispatch_io() */ io.sleeper = current; + io.client = client; dispatch_io(rw, num_regions, where, dp, &io, 1); @@ -348,12 +371,15 @@ static int sync_io(unsigned int num_regions, struct io_region *where, if (atomic_read(&io.count)) return -EINTR; - *error_bits = io.error; + if (error_bits) + *error_bits = io.error; + return io.error ? -EIO : 0; } -static int async_io(unsigned int num_regions, struct io_region *where, int rw, - struct dpages *dp, io_notify_fn fn, void *context) +static int async_io(struct dm_io_client *client, unsigned int num_regions, + struct io_region *where, int rw, struct dpages *dp, + io_notify_fn fn, void *context) { struct io *io; @@ -363,10 +389,11 @@ static int async_io(unsigned int num_regions, struct io_region *where, int rw, return -EIO; } - io = mempool_alloc(_io_pool, GFP_NOIO); + io = mempool_alloc(io_pool(client), GFP_NOIO); io->error = 0; atomic_set(&io->count, 1); /* see dispatch_io() */ io->sleeper = NULL; + io->client = client; io->callback = fn; io->context = context; @@ -380,7 +407,7 @@ int dm_io_sync(unsigned int num_regions, struct io_region *where, int rw, { struct dpages dp; list_dp_init(&dp, pl, offset); - return sync_io(num_regions, where, rw, &dp, error_bits); + return sync_io(NULL, num_regions, where, rw, &dp, error_bits); } int dm_io_sync_bvec(unsigned int num_regions, struct io_region *where, int rw, @@ -388,7 +415,7 @@ int dm_io_sync_bvec(unsigned int num_regions, struct io_region *where, int rw, { struct dpages dp; bvec_dp_init(&dp, bvec); - return sync_io(num_regions, where, rw, &dp, error_bits); + return sync_io(NULL, num_regions, where, rw, &dp, error_bits); } int dm_io_sync_vm(unsigned int num_regions, struct io_region *where, int rw, @@ -396,7 +423,7 @@ int dm_io_sync_vm(unsigned int num_regions, struct io_region *where, int rw, { struct dpages dp; vm_dp_init(&dp, data); - return sync_io(num_regions, where, rw, &dp, error_bits); + return sync_io(NULL, num_regions, where, rw, &dp, error_bits); } int dm_io_async(unsigned int num_regions, struct io_region *where, int rw, @@ -405,7 +432,7 @@ int dm_io_async(unsigned int num_regions, struct io_region *where, int rw, { struct dpages dp; list_dp_init(&dp, pl, offset); - return async_io(num_regions, where, rw, &dp, fn, context); + return async_io(NULL, num_regions, where, rw, &dp, fn, context); } int dm_io_async_bvec(unsigned int num_regions, struct io_region *where, int rw, @@ -413,7 +440,7 @@ int dm_io_async_bvec(unsigned int num_regions, struct io_region *where, int rw, { struct dpages dp; bvec_dp_init(&dp, bvec); - return async_io(num_regions, where, rw, &dp, fn, context); + return async_io(NULL, num_regions, where, rw, &dp, fn, context); } int dm_io_async_vm(unsigned int num_regions, struct io_region *where, int rw, @@ -421,7 +448,7 @@ int dm_io_async_vm(unsigned int num_regions, struct io_region *where, int rw, { struct dpages dp; vm_dp_init(&dp, data); - return async_io(num_regions, where, rw, &dp, fn, context); + return async_io(NULL, num_regions, where, rw, &dp, fn, context); } EXPORT_SYMBOL(dm_io_get); |