diff options
author | Dan Williams <dan.j.williams@intel.com> | 2015-06-25 04:20:04 -0400 |
---|---|---|
committer | Dan Williams <dan.j.williams@intel.com> | 2015-06-25 04:20:04 -0400 |
commit | 8c2f7e8658df1d3b7cbfa62706941d14c715823a (patch) | |
tree | ac93512841113f4d1d7a38d788ec73bb21e2d605 /drivers/nvdimm/pmem.c | |
parent | 0ba1c634892b3590779803a701bcb82e8c32cc7a (diff) |
libnvdimm: infrastructure for btt devices
NVDIMM namespaces, in addition to accepting "struct bio" based requests,
also have the capability to perform byte-aligned accesses. By default
only the bio/block interface is used. However, if another driver can
make effective use of the byte-aligned capability it can claim namespace
interface and use the byte-aligned ->rw_bytes() interface.
The BTT driver is the initial first consumer of this mechanism to allow
adding atomic sector update semantics to a pmem or blk namespace. This
patch is the sysfs infrastructure to allow configuring a BTT instance
for a namespace. Enabling that BTT and performing i/o is in a
subsequent patch.
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/nvdimm/pmem.c')
-rw-r--r-- | drivers/nvdimm/pmem.c | 132 |
1 files changed, 84 insertions, 48 deletions
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 90902a142e35..d0c6b4bdba69 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -121,44 +121,61 @@ static struct pmem_device *pmem_alloc(struct device *dev, struct resource *res, int id) { struct pmem_device *pmem; - struct gendisk *disk; - int err; - err = -ENOMEM; pmem = kzalloc(sizeof(*pmem), GFP_KERNEL); if (!pmem) - goto out; + return ERR_PTR(-ENOMEM); pmem->phys_addr = res->start; pmem->size = resource_size(res); - err = -EINVAL; - if (!request_mem_region(pmem->phys_addr, pmem->size, "pmem")) { + if (!request_mem_region(pmem->phys_addr, pmem->size, dev_name(dev))) { dev_warn(dev, "could not reserve region [0x%pa:0x%zx]\n", &pmem->phys_addr, pmem->size); - goto out_free_dev; + kfree(pmem); + return ERR_PTR(-EBUSY); } /* * Map the memory as non-cachable, as we can't write back the contents * of the CPU caches in case of a crash. */ - err = -ENOMEM; pmem->virt_addr = ioremap_nocache(pmem->phys_addr, pmem->size); - if (!pmem->virt_addr) - goto out_release_region; + if (!pmem->virt_addr) { + release_mem_region(pmem->phys_addr, pmem->size); + kfree(pmem); + return ERR_PTR(-ENXIO); + } + + return pmem; +} + +static void pmem_detach_disk(struct pmem_device *pmem) +{ + del_gendisk(pmem->pmem_disk); + put_disk(pmem->pmem_disk); + blk_cleanup_queue(pmem->pmem_queue); +} + +static int pmem_attach_disk(struct nd_namespace_common *ndns, + struct pmem_device *pmem) +{ + struct nd_region *nd_region = to_nd_region(ndns->dev.parent); + struct gendisk *disk; pmem->pmem_queue = blk_alloc_queue(GFP_KERNEL); if (!pmem->pmem_queue) - goto out_unmap; + return -ENOMEM; blk_queue_make_request(pmem->pmem_queue, pmem_make_request); blk_queue_max_hw_sectors(pmem->pmem_queue, 1024); blk_queue_bounce_limit(pmem->pmem_queue, BLK_BOUNCE_ANY); disk = alloc_disk(0); - if (!disk) - goto out_free_queue; + if (!disk) { + blk_cleanup_queue(pmem->pmem_queue); + return -ENOMEM; + } disk->major = pmem_major; disk->first_minor = 0; @@ -166,32 +183,47 @@ static struct pmem_device *pmem_alloc(struct device *dev, disk->private_data = pmem; disk->queue = pmem->pmem_queue; disk->flags = GENHD_FL_EXT_DEVT; - sprintf(disk->disk_name, "pmem%d", id); - disk->driverfs_dev = dev; + sprintf(disk->disk_name, "pmem%d", nd_region->id); + disk->driverfs_dev = &ndns->dev; set_capacity(disk, pmem->size >> 9); pmem->pmem_disk = disk; add_disk(disk); - return pmem; + return 0; +} -out_free_queue: - blk_cleanup_queue(pmem->pmem_queue); -out_unmap: - iounmap(pmem->virt_addr); -out_release_region: - release_mem_region(pmem->phys_addr, pmem->size); -out_free_dev: - kfree(pmem); -out: - return ERR_PTR(err); +static int pmem_rw_bytes(struct nd_namespace_common *ndns, + resource_size_t offset, void *buf, size_t size, int rw) +{ + struct pmem_device *pmem = dev_get_drvdata(ndns->claim); + + if (unlikely(offset + size > pmem->size)) { + dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n"); + return -EFAULT; + } + + if (rw == READ) + memcpy(buf, pmem->virt_addr + offset, size); + else + memcpy(pmem->virt_addr + offset, buf, size); + + return 0; +} + +static int nvdimm_namespace_attach_btt(struct nd_namespace_common *ndns) +{ + /* TODO */ + return -ENXIO; +} + +static void nvdimm_namespace_detach_btt(struct nd_namespace_common *ndns) +{ + /* TODO */ } static void pmem_free(struct pmem_device *pmem) { - del_gendisk(pmem->pmem_disk); - put_disk(pmem->pmem_disk); - blk_cleanup_queue(pmem->pmem_queue); iounmap(pmem->virt_addr); release_mem_region(pmem->phys_addr, pmem->size); kfree(pmem); @@ -200,40 +232,44 @@ static void pmem_free(struct pmem_device *pmem) static int nd_pmem_probe(struct device *dev) { struct nd_region *nd_region = to_nd_region(dev->parent); - struct nd_namespace_io *nsio = to_nd_namespace_io(dev); + struct nd_namespace_common *ndns; + struct nd_namespace_io *nsio; struct pmem_device *pmem; + int rc; - if (resource_size(&nsio->res) < ND_MIN_NAMESPACE_SIZE) { - resource_size_t size = resource_size(&nsio->res); - - dev_dbg(dev, "%s: size: %pa, too small must be at least %#x\n", - __func__, &size, ND_MIN_NAMESPACE_SIZE); - return -ENODEV; - } - - if (nd_region_to_nstype(nd_region) == ND_DEVICE_NAMESPACE_PMEM) { - struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev); - - if (!nspm->uuid) { - dev_dbg(dev, "%s: uuid not set\n", __func__); - return -ENODEV; - } - } + ndns = nvdimm_namespace_common_probe(dev); + if (IS_ERR(ndns)) + return PTR_ERR(ndns); + nsio = to_nd_namespace_io(&ndns->dev); pmem = pmem_alloc(dev, &nsio->res, nd_region->id); if (IS_ERR(pmem)) return PTR_ERR(pmem); dev_set_drvdata(dev, pmem); - - return 0; + ndns->rw_bytes = pmem_rw_bytes; + if (is_nd_btt(dev)) + rc = nvdimm_namespace_attach_btt(ndns); + else if (nd_btt_probe(ndns, pmem) == 0) { + /* we'll come back as btt-pmem */ + rc = -ENXIO; + } else + rc = pmem_attach_disk(ndns, pmem); + if (rc) + pmem_free(pmem); + return rc; } static int nd_pmem_remove(struct device *dev) { struct pmem_device *pmem = dev_get_drvdata(dev); + if (is_nd_btt(dev)) + nvdimm_namespace_detach_btt(to_nd_btt(dev)->ndns); + else + pmem_detach_disk(pmem); pmem_free(pmem); + return 0; } |