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author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-09 00:35:59 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-09 00:35:59 +0300 |
commit | 12f03ee606914317e7e6a0815e53a48205c31dae (patch) | |
tree | f8579bf77d29b3921e1877e0ae12ec65b5ebc738 /fs/dax.c | |
parent | d9241b22b58e012f26dd2244508d9f4837402af0 (diff) | |
parent | 004f1afbe199e6ab20805b95aefd83ccd24bc5c7 (diff) | |
download | linux-12f03ee606914317e7e6a0815e53a48205c31dae.tar.xz |
Merge tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"This update has successfully completed a 0day-kbuild run and has
appeared in a linux-next release. The changes outside of the typical
drivers/nvdimm/ and drivers/acpi/nfit.[ch] paths are related to the
removal of IORESOURCE_CACHEABLE, the introduction of memremap(), and
the introduction of ZONE_DEVICE + devm_memremap_pages().
Summary:
- Introduce ZONE_DEVICE and devm_memremap_pages() as a generic
mechanism for adding device-driver-discovered memory regions to the
kernel's direct map.
This facility is used by the pmem driver to enable pfn_to_page()
operations on the page frames returned by DAX ('direct_access' in
'struct block_device_operations').
For now, the 'memmap' allocation for these "device" pages comes
from "System RAM". Support for allocating the memmap from device
memory will arrive in a later kernel.
- Introduce memremap() to replace usages of ioremap_cache() and
ioremap_wt(). memremap() drops the __iomem annotation for these
mappings to memory that do not have i/o side effects. The
replacement of ioremap_cache() with memremap() is limited to the
pmem driver to ease merging the api change in v4.3.
Completion of the conversion is targeted for v4.4.
- Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem
driver, update the VFS DAX implementation and PMEM api to provide
persistence guarantees for kernel operations on a DAX mapping.
- Convert the ACPI NFIT 'BLK' driver to map the block apertures as
cacheable to improve performance.
- Miscellaneous updates and fixes to libnvdimm including support for
issuing "address range scrub" commands, clarifying the optimal
'sector size' of pmem devices, a clarification of the usage of the
ACPI '_STA' (status) property for DIMM devices, and other minor
fixes"
* tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (34 commits)
libnvdimm, pmem: direct map legacy pmem by default
libnvdimm, pmem: 'struct page' for pmem
libnvdimm, pfn: 'struct page' provider infrastructure
x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB
add devm_memremap_pages
mm: ZONE_DEVICE for "device memory"
mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h
dax: drop size parameter to ->direct_access()
nd_blk: change aperture mapping from WC to WB
nvdimm: change to use generic kvfree()
pmem, dax: have direct_access use __pmem annotation
dax: update I/O path to do proper PMEM flushing
pmem: add copy_from_iter_pmem() and clear_pmem()
pmem, x86: clean up conditional pmem includes
pmem: remove layer when calling arch_has_wmb_pmem()
pmem, x86: move x86 PMEM API to new pmem.h header
libnvdimm, e820: make CONFIG_X86_PMEM_LEGACY a tristate option
pmem: switch to devm_ allocations
devres: add devm_memremap
libnvdimm, btt: write and validate parent_uuid
...
Diffstat (limited to 'fs/dax.c')
-rw-r--r-- | fs/dax.c | 62 |
1 files changed, 38 insertions, 24 deletions
@@ -23,6 +23,7 @@ #include <linux/memcontrol.h> #include <linux/mm.h> #include <linux/mutex.h> +#include <linux/pmem.h> #include <linux/sched.h> #include <linux/uio.h> #include <linux/vmstat.h> @@ -34,7 +35,7 @@ int dax_clear_blocks(struct inode *inode, sector_t block, long size) might_sleep(); do { - void *addr; + void __pmem *addr; unsigned long pfn; long count; @@ -46,10 +47,7 @@ int dax_clear_blocks(struct inode *inode, sector_t block, long size) unsigned pgsz = PAGE_SIZE - offset_in_page(addr); if (pgsz > count) pgsz = count; - if (pgsz < PAGE_SIZE) - memset(addr, 0, pgsz); - else - clear_page(addr); + clear_pmem(addr, pgsz); addr += pgsz; size -= pgsz; count -= pgsz; @@ -59,26 +57,29 @@ int dax_clear_blocks(struct inode *inode, sector_t block, long size) } } while (size); + wmb_pmem(); return 0; } EXPORT_SYMBOL_GPL(dax_clear_blocks); -static long dax_get_addr(struct buffer_head *bh, void **addr, unsigned blkbits) +static long dax_get_addr(struct buffer_head *bh, void __pmem **addr, + unsigned blkbits) { unsigned long pfn; sector_t sector = bh->b_blocknr << (blkbits - 9); return bdev_direct_access(bh->b_bdev, sector, addr, &pfn, bh->b_size); } -static void dax_new_buf(void *addr, unsigned size, unsigned first, loff_t pos, - loff_t end) +/* the clear_pmem() calls are ordered by a wmb_pmem() in the caller */ +static void dax_new_buf(void __pmem *addr, unsigned size, unsigned first, + loff_t pos, loff_t end) { loff_t final = end - pos + first; /* The final byte of the buffer */ if (first > 0) - memset(addr, 0, first); + clear_pmem(addr, first); if (final < size) - memset(addr + final, 0, size - final); + clear_pmem(addr + final, size - final); } static bool buffer_written(struct buffer_head *bh) @@ -106,14 +107,15 @@ static ssize_t dax_io(struct inode *inode, struct iov_iter *iter, loff_t pos = start; loff_t max = start; loff_t bh_max = start; - void *addr; + void __pmem *addr; bool hole = false; + bool need_wmb = false; if (iov_iter_rw(iter) != WRITE) end = min(end, i_size_read(inode)); while (pos < end) { - unsigned len; + size_t len; if (pos == max) { unsigned blkbits = inode->i_blkbits; sector_t block = pos >> blkbits; @@ -145,19 +147,23 @@ static ssize_t dax_io(struct inode *inode, struct iov_iter *iter, retval = dax_get_addr(bh, &addr, blkbits); if (retval < 0) break; - if (buffer_unwritten(bh) || buffer_new(bh)) + if (buffer_unwritten(bh) || buffer_new(bh)) { dax_new_buf(addr, retval, first, pos, end); + need_wmb = true; + } addr += first; size = retval - first; } max = min(pos + size, end); } - if (iov_iter_rw(iter) == WRITE) - len = copy_from_iter_nocache(addr, max - pos, iter); - else if (!hole) - len = copy_to_iter(addr, max - pos, iter); + if (iov_iter_rw(iter) == WRITE) { + len = copy_from_iter_pmem(addr, max - pos, iter); + need_wmb = true; + } else if (!hole) + len = copy_to_iter((void __force *)addr, max - pos, + iter); else len = iov_iter_zero(max - pos, iter); @@ -168,6 +174,9 @@ static ssize_t dax_io(struct inode *inode, struct iov_iter *iter, addr += len; } + if (need_wmb) + wmb_pmem(); + return (pos == start) ? retval : pos - start; } @@ -260,11 +269,13 @@ static int dax_load_hole(struct address_space *mapping, struct page *page, static int copy_user_bh(struct page *to, struct buffer_head *bh, unsigned blkbits, unsigned long vaddr) { - void *vfrom, *vto; + void __pmem *vfrom; + void *vto; + if (dax_get_addr(bh, &vfrom, blkbits) < 0) return -EIO; vto = kmap_atomic(to); - copy_user_page(vto, vfrom, vaddr, to); + copy_user_page(vto, (void __force *)vfrom, vaddr, to); kunmap_atomic(vto); return 0; } @@ -275,7 +286,7 @@ static int dax_insert_mapping(struct inode *inode, struct buffer_head *bh, struct address_space *mapping = inode->i_mapping; sector_t sector = bh->b_blocknr << (inode->i_blkbits - 9); unsigned long vaddr = (unsigned long)vmf->virtual_address; - void *addr; + void __pmem *addr; unsigned long pfn; pgoff_t size; int error; @@ -303,8 +314,10 @@ static int dax_insert_mapping(struct inode *inode, struct buffer_head *bh, goto out; } - if (buffer_unwritten(bh) || buffer_new(bh)) - clear_page(addr); + if (buffer_unwritten(bh) || buffer_new(bh)) { + clear_pmem(addr, PAGE_SIZE); + wmb_pmem(); + } error = vm_insert_mixed(vma, vaddr, pfn); @@ -548,11 +561,12 @@ int dax_zero_page_range(struct inode *inode, loff_t from, unsigned length, if (err < 0) return err; if (buffer_written(&bh)) { - void *addr; + void __pmem *addr; err = dax_get_addr(&bh, &addr, inode->i_blkbits); if (err < 0) return err; - memset(addr + offset, 0, length); + clear_pmem(addr + offset, length); + wmb_pmem(); } return 0; |