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| author | Dan Williams <dan.j.williams@intel.com> | 2016-01-16 03:56:14 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-16 04:56:32 +0300 |
| commit | 34c0fd540e79fb49ef9ce864dae1058cca265780 (patch) | |
| tree | 7f404f3a644322d0eca02b54daa228261ed24f39 /drivers/nvdimm | |
| parent | ba049e93aef7e8c571567088b1b73f4f5b99272a (diff) | |
| download | linux-34c0fd540e79fb49ef9ce864dae1058cca265780.tar.xz | |
mm, dax, pmem: introduce pfn_t
For the purpose of communicating the optional presence of a 'struct
page' for the pfn returned from ->direct_access(), introduce a type that
encapsulates a page-frame-number plus flags. These flags contain the
historical "page_link" encoding for a scatterlist entry, but can also
denote "device memory". Where "device memory" is a set of pfns that are
not part of the kernel's linear mapping by default, but are accessed via
the same memory controller as ram.
The motivation for this new type is large capacity persistent memory
that needs struct page entries in the 'memmap' to support 3rd party DMA
(i.e. O_DIRECT I/O with a persistent memory source/target). However,
we also need it in support of maintaining a list of mapped inodes which
need to be unmapped at driver teardown or freeze_bdev() time.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Hansen <dave@sr71.net>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/nvdimm')
| -rw-r--r-- | drivers/nvdimm/pmem.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index b493ff3fccb2..5def7f4ddbd2 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -25,6 +25,7 @@ #include <linux/moduleparam.h> #include <linux/badblocks.h> #include <linux/vmalloc.h> +#include <linux/pfn_t.h> #include <linux/slab.h> #include <linux/pmem.h> #include <linux/nd.h> @@ -40,6 +41,7 @@ struct pmem_device { phys_addr_t phys_addr; /* when non-zero this device is hosting a 'pfn' instance */ phys_addr_t data_offset; + unsigned long pfn_flags; void __pmem *virt_addr; size_t size; struct badblocks bb; @@ -135,13 +137,13 @@ static int pmem_rw_page(struct block_device *bdev, sector_t sector, } static long pmem_direct_access(struct block_device *bdev, sector_t sector, - void __pmem **kaddr, unsigned long *pfn) + void __pmem **kaddr, pfn_t *pfn) { struct pmem_device *pmem = bdev->bd_disk->private_data; resource_size_t offset = sector * 512 + pmem->data_offset; *kaddr = pmem->virt_addr + offset; - *pfn = (pmem->phys_addr + offset) >> PAGE_SHIFT; + *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); return pmem->size - offset; } @@ -174,9 +176,11 @@ static struct pmem_device *pmem_alloc(struct device *dev, return ERR_PTR(-EBUSY); } - if (pmem_should_map_pages(dev)) + pmem->pfn_flags = PFN_DEV; + if (pmem_should_map_pages(dev)) { pmem->virt_addr = (void __pmem *) devm_memremap_pages(dev, res); - else + pmem->pfn_flags |= PFN_MAP; + } else pmem->virt_addr = (void __pmem *) devm_memremap(dev, pmem->phys_addr, pmem->size, ARCH_MEMREMAP_PMEM); @@ -384,6 +388,7 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns) pmem = dev_get_drvdata(dev); devm_memunmap(dev, (void __force *) pmem->virt_addr); pmem->virt_addr = (void __pmem *) devm_memremap_pages(dev, &nsio->res); + pmem->pfn_flags |= PFN_MAP; if (IS_ERR(pmem->virt_addr)) { rc = PTR_ERR(pmem->virt_addr); goto err; |