From cfe30b872058f211630eda7f65fb19d83beaaa3c Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Thu, 3 Mar 2016 09:38:00 -0800 Subject: [PATCH] libnvdimm, pmem: adjust for section collisions with 'System RAM' On a platform where 'Persistent Memory' and 'System RAM' are mixed within a given sparsemem section, trim the namespace and notify about the sub-optimal alignment. Cc: Toshi Kani Cc: Ross Zwisler Signed-off-by: Dan Williams --- drivers/nvdimm/namespace_devs.c | 7 ++ drivers/nvdimm/pfn.h | 10 ++- drivers/nvdimm/pfn_devs.c | 5 ++ drivers/nvdimm/pmem.c | 125 +++++++++++++++++++++++--------- 4 files changed, 111 insertions(+), 36 deletions(-) diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c index 9edf7eb7d17c..f5cb88601359 100644 --- a/drivers/nvdimm/namespace_devs.c +++ b/drivers/nvdimm/namespace_devs.c @@ -133,6 +133,7 @@ bool nd_is_uuid_unique(struct device *dev, u8 *uuid) bool pmem_should_map_pages(struct device *dev) { struct nd_region *nd_region = to_nd_region(dev->parent); + struct nd_namespace_io *nsio; if (!IS_ENABLED(CONFIG_ZONE_DEVICE)) return false; @@ -143,6 +144,12 @@ bool pmem_should_map_pages(struct device *dev) if (is_nd_pfn(dev) || is_nd_btt(dev)) return false; + nsio = to_nd_namespace_io(dev); + if (region_intersects(nsio->res.start, resource_size(&nsio->res), + IORESOURCE_SYSTEM_RAM, + IORES_DESC_NONE) == REGION_MIXED) + return false; + #ifdef ARCH_MEMREMAP_PMEM return ARCH_MEMREMAP_PMEM == MEMREMAP_WB; #else diff --git a/drivers/nvdimm/pfn.h b/drivers/nvdimm/pfn.h index 6ee707e5b279..8e343a3ca873 100644 --- a/drivers/nvdimm/pfn.h +++ b/drivers/nvdimm/pfn.h @@ -27,10 +27,13 @@ struct nd_pfn_sb { __le32 flags; __le16 version_major; __le16 version_minor; - __le64 dataoff; + __le64 dataoff; /* relative to namespace_base + start_pad */ __le64 npfns; __le32 mode; - u8 padding[4012]; + /* minor-version-1 additions for section alignment */ + __le32 start_pad; + __le32 end_trunc; + u8 padding[4004]; __le64 checksum; }; @@ -45,4 +48,7 @@ struct nd_pfn_sb { #define PFN_SECTION_ALIGN_DOWN(x) (x) #define PFN_SECTION_ALIGN_UP(x) (x) #endif + +#define PHYS_SECTION_ALIGN_DOWN(x) PFN_PHYS(PFN_SECTION_ALIGN_DOWN(PHYS_PFN(x))) +#define PHYS_SECTION_ALIGN_UP(x) PFN_PHYS(PFN_SECTION_ALIGN_UP(PHYS_PFN(x))) #endif /* __NVDIMM_PFN_H */ diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index ae81a2f1da50..75a31a7359fb 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -299,6 +299,11 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn) if (memcmp(pfn_sb->parent_uuid, parent_uuid, 16) != 0) return -ENODEV; + if (__le16_to_cpu(pfn_sb->version_minor) < 1) { + pfn_sb->start_pad = 0; + pfn_sb->end_trunc = 0; + } + switch (le32_to_cpu(pfn_sb->mode)) { case PFN_MODE_RAM: case PFN_MODE_PMEM: diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 59d568ab7556..0cb450e1b400 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -43,7 +43,10 @@ struct pmem_device { phys_addr_t data_offset; u64 pfn_flags; void __pmem *virt_addr; + /* immutable base size of the namespace */ size_t size; + /* trim size when namespace capacity has been section aligned */ + u32 pfn_pad; struct badblocks bb; }; @@ -145,7 +148,7 @@ static long pmem_direct_access(struct block_device *bdev, sector_t sector, *kaddr = pmem->virt_addr + offset; *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); - return pmem->size - offset; + return pmem->size - pmem->pfn_pad - offset; } static const struct block_device_operations pmem_fops = { @@ -236,7 +239,8 @@ static int pmem_attach_disk(struct device *dev, disk->flags = GENHD_FL_EXT_DEVT; nvdimm_namespace_disk_name(ndns, disk->disk_name); disk->driverfs_dev = dev; - set_capacity(disk, (pmem->size - pmem->data_offset) / 512); + set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset) + / 512); pmem->pmem_disk = disk; devm_exit_badblocks(dev, &pmem->bb); if (devm_init_badblocks(dev, &pmem->bb)) @@ -279,6 +283,9 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn) struct nd_pfn_sb *pfn_sb = kzalloc(sizeof(*pfn_sb), GFP_KERNEL); struct pmem_device *pmem = dev_get_drvdata(&nd_pfn->dev); struct nd_namespace_common *ndns = nd_pfn->ndns; + u32 start_pad = 0, end_trunc = 0; + resource_size_t start, size; + struct nd_namespace_io *nsio; struct nd_region *nd_region; unsigned long npfns; phys_addr_t offset; @@ -304,21 +311,56 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn) } memset(pfn_sb, 0, sizeof(*pfn_sb)); - npfns = (pmem->size - SZ_8K) / SZ_4K; + + /* + * Check if pmem collides with 'System RAM' when section aligned and + * trim it accordingly + */ + nsio = to_nd_namespace_io(&ndns->dev); + start = PHYS_SECTION_ALIGN_DOWN(nsio->res.start); + size = resource_size(&nsio->res); + if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM, + IORES_DESC_NONE) == REGION_MIXED) { + + start = nsio->res.start; + start_pad = PHYS_SECTION_ALIGN_UP(start) - start; + } + + start = nsio->res.start; + size = PHYS_SECTION_ALIGN_UP(start + size) - start; + if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM, + IORES_DESC_NONE) == REGION_MIXED) { + size = resource_size(&nsio->res); + end_trunc = start + size - PHYS_SECTION_ALIGN_DOWN(start + size); + } + + if (start_pad + end_trunc) + dev_info(&nd_pfn->dev, "%s section collision, truncate %d bytes\n", + dev_name(&ndns->dev), start_pad + end_trunc); + /* * Note, we use 64 here for the standard size of struct page, * debugging options may cause it to be larger in which case the * implementation will limit the pfns advertised through * ->direct_access() to those that are included in the memmap. */ + start += start_pad; + npfns = (pmem->size - start_pad - end_trunc - SZ_8K) / SZ_4K; if (nd_pfn->mode == PFN_MODE_PMEM) - offset = ALIGN(SZ_8K + 64 * npfns, nd_pfn->align); + offset = ALIGN(start + SZ_8K + 64 * npfns, nd_pfn->align) + - start; else if (nd_pfn->mode == PFN_MODE_RAM) - offset = ALIGN(SZ_8K, nd_pfn->align); + offset = ALIGN(start + SZ_8K, nd_pfn->align) - start; else goto err; - npfns = (pmem->size - offset) / SZ_4K; + if (offset + start_pad + end_trunc >= pmem->size) { + dev_err(&nd_pfn->dev, "%s unable to satisfy requested alignment\n", + dev_name(&ndns->dev)); + goto err; + } + + npfns = (pmem->size - offset - start_pad - end_trunc) / SZ_4K; pfn_sb->mode = cpu_to_le32(nd_pfn->mode); pfn_sb->dataoff = cpu_to_le64(offset); pfn_sb->npfns = cpu_to_le64(npfns); @@ -326,6 +368,9 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn) memcpy(pfn_sb->uuid, nd_pfn->uuid, 16); memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16); pfn_sb->version_major = cpu_to_le16(1); + pfn_sb->version_minor = cpu_to_le16(1); + pfn_sb->start_pad = cpu_to_le32(start_pad); + pfn_sb->end_trunc = cpu_to_le32(end_trunc); checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb); pfn_sb->checksum = cpu_to_le64(checksum); @@ -376,41 +421,36 @@ static unsigned long init_altmap_reserve(resource_size_t base) return reserve; } -static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns) +static int __nvdimm_namespace_attach_pfn(struct nd_pfn *nd_pfn) { - struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); - struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim); - struct device *dev = &nd_pfn->dev; - struct nd_region *nd_region; - struct vmem_altmap *altmap; - struct nd_pfn_sb *pfn_sb; - struct pmem_device *pmem; - struct request_queue *q; - phys_addr_t offset; int rc; + struct resource res; + struct request_queue *q; + struct pmem_device *pmem; + struct vmem_altmap *altmap; + struct device *dev = &nd_pfn->dev; + struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; + struct nd_namespace_common *ndns = nd_pfn->ndns; + u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); + u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc); + struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); + resource_size_t base = nsio->res.start + start_pad; struct vmem_altmap __altmap = { - .base_pfn = init_altmap_base(nsio->res.start), - .reserve = init_altmap_reserve(nsio->res.start), + .base_pfn = init_altmap_base(base), + .reserve = init_altmap_reserve(base), }; - if (!nd_pfn->uuid || !nd_pfn->ndns) - return -ENODEV; - - nd_region = to_nd_region(dev->parent); - rc = nd_pfn_init(nd_pfn); - if (rc) - return rc; - - pfn_sb = nd_pfn->pfn_sb; - offset = le64_to_cpu(pfn_sb->dataoff); + pmem = dev_get_drvdata(dev); + pmem->data_offset = le64_to_cpu(pfn_sb->dataoff); + pmem->pfn_pad = start_pad + end_trunc; nd_pfn->mode = le32_to_cpu(nd_pfn->pfn_sb->mode); if (nd_pfn->mode == PFN_MODE_RAM) { - if (offset < SZ_8K) + if (pmem->data_offset < SZ_8K) return -EINVAL; nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns); altmap = NULL; } else if (nd_pfn->mode == PFN_MODE_PMEM) { - nd_pfn->npfns = (resource_size(&nsio->res) - offset) + nd_pfn->npfns = (pmem->size - pmem->pfn_pad - pmem->data_offset) / PAGE_SIZE; if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns) dev_info(&nd_pfn->dev, @@ -418,7 +458,7 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns) le64_to_cpu(nd_pfn->pfn_sb->npfns), nd_pfn->npfns); altmap = & __altmap; - altmap->free = __phys_to_pfn(offset - SZ_8K); + altmap->free = __phys_to_pfn(pmem->data_offset - SZ_8K); altmap->alloc = 0; } else { rc = -ENXIO; @@ -426,10 +466,12 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns) } /* establish pfn range for lookup, and switch to direct map */ - pmem = dev_get_drvdata(dev); q = pmem->pmem_queue; + memcpy(&res, &nsio->res, sizeof(res)); + res.start += start_pad; + res.end -= end_trunc; devm_memunmap(dev, (void __force *) pmem->virt_addr); - pmem->virt_addr = (void __pmem *) devm_memremap_pages(dev, &nsio->res, + pmem->virt_addr = (void __pmem *) devm_memremap_pages(dev, &res, &q->q_usage_counter, altmap); pmem->pfn_flags |= PFN_MAP; if (IS_ERR(pmem->virt_addr)) { @@ -438,7 +480,6 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns) } /* attach pmem disk in "pfn-mode" */ - pmem->data_offset = offset; rc = pmem_attach_disk(dev, ndns, pmem); if (rc) goto err; @@ -447,6 +488,22 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns) err: nvdimm_namespace_detach_pfn(ndns); return rc; + +} + +static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns) +{ + struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim); + int rc; + + if (!nd_pfn->uuid || !nd_pfn->ndns) + return -ENODEV; + + rc = nd_pfn_init(nd_pfn); + if (rc) + return rc; + /* we need a valid pfn_sb before we can init a vmem_altmap */ + return __nvdimm_namespace_attach_pfn(nd_pfn); } static int nd_pmem_probe(struct device *dev) -- 2.20.1