From adf6895754e2503d994a765535fd1813f8834674 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Thu, 30 Nov 2017 19:42:52 -0800 Subject: [PATCH 1/5] acpi, nfit: fix health event notification Integration testing with a BIOS that generates injected health event notifications fails to communicate those events to userspace. The nfit driver neglects to link the ACPI DIMM device with the necessary driver data so acpi_nvdimm_notify() fails this lookup: nfit_mem = dev_get_drvdata(dev); if (nfit_mem && nfit_mem->flags_attr) sysfs_notify_dirent(nfit_mem->flags_attr); Add the necessary linkage when installing the notification handler and clean it up when the nfit driver instance is torn down. Cc: Cc: Toshi Kani Cc: Vishal Verma Fixes: ba9c8dd3c222 ("acpi, nfit: add dimm device notification support") Reported-by: Daniel Osawa Tested-by: Daniel Osawa Signed-off-by: Dan Williams --- drivers/acpi/nfit/core.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index ff2580e7611d18..abeb4df4f22e43 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -1670,6 +1670,11 @@ static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc, dev_name(&adev_dimm->dev)); return -ENXIO; } + /* + * Record nfit_mem for the notification path to track back to + * the nfit sysfs attributes for this dimm device object. + */ + dev_set_drvdata(&adev_dimm->dev, nfit_mem); /* * Until standardization materializes we need to consider 4 @@ -1752,9 +1757,11 @@ static void shutdown_dimm_notify(void *data) sysfs_put(nfit_mem->flags_attr); nfit_mem->flags_attr = NULL; } - if (adev_dimm) + if (adev_dimm) { acpi_remove_notify_handler(adev_dimm->handle, ACPI_DEVICE_NOTIFY, acpi_nvdimm_notify); + dev_set_drvdata(&adev_dimm->dev, NULL); + } } mutex_unlock(&acpi_desc->init_mutex); } From 19deaa217bc04e83b59b5e8c8229eb0e53ad9efc Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 19 Dec 2017 15:07:10 -0800 Subject: [PATCH 2/5] libnvdimm, pfn: fix start_pad handling for aligned namespaces The alignment checks at pfn driver startup fail to properly account for the 'start_pad' in the case where the namespace is misaligned relative to its internal alignment. This is typically triggered in 1G aligned namespace, but could theoretically trigger with small namespace alignments. When this triggers the kernel reports messages of the form: dax2.1: bad offset: 0x3c000000 dax disabled align: 0x40000000 Cc: Fixes: 1ee6667cd8d1 ("libnvdimm, pfn, dax: fix initialization vs autodetect...") Reported-by: Jane Chu Signed-off-by: Dan Williams --- drivers/nvdimm/pfn_devs.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 65cc171c721de8..db2fc7c02e01c0 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -364,9 +364,9 @@ struct device *nd_pfn_create(struct nd_region *nd_region) int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig) { u64 checksum, offset; - unsigned long align; enum nd_pfn_mode mode; struct nd_namespace_io *nsio; + unsigned long align, start_pad; struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; struct nd_namespace_common *ndns = nd_pfn->ndns; const u8 *parent_uuid = nd_dev_to_uuid(&ndns->dev); @@ -410,6 +410,7 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig) align = le32_to_cpu(pfn_sb->align); offset = le64_to_cpu(pfn_sb->dataoff); + start_pad = le32_to_cpu(pfn_sb->start_pad); if (align == 0) align = 1UL << ilog2(offset); mode = le32_to_cpu(pfn_sb->mode); @@ -468,7 +469,7 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig) return -EBUSY; } - if ((align && !IS_ALIGNED(offset, align)) + if ((align && !IS_ALIGNED(nsio->res.start + offset + start_pad, align)) || !IS_ALIGNED(offset, PAGE_SIZE)) { dev_err(&nd_pfn->dev, "bad offset: %#llx dax disabled align: %#lx\n", From 41fce90f26333c4fa82e8e43b9ace86c4e8a0120 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 4 Dec 2017 14:07:43 -0800 Subject: [PATCH 3/5] libnvdimm, dax: fix 1GB-aligned namespaces vs physical misalignment The following namespace configuration attempt: # ndctl create-namespace -e namespace0.0 -m devdax -a 1G -f libndctl: ndctl_dax_enable: dax0.1: failed to enable Error: namespace0.0: failed to enable failed to reconfigure namespace: No such device or address ...fails when the backing memory range is not physically aligned to 1G: # cat /proc/iomem | grep Persistent 210000000-30fffffff : Persistent Memory (legacy) In the above example the 4G persistent memory range starts and ends on a 256MB boundary. We handle this case correctly when needing to handle cases that violate section alignment (128MB) collisions against "System RAM", and we simply need to extend that padding/truncation for the 1GB alignment use case. Cc: Fixes: 315c562536c4 ("libnvdimm, pfn: add 'align' attribute...") Reported-and-tested-by: Jane Chu Signed-off-by: Dan Williams --- drivers/nvdimm/pfn_devs.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index db2fc7c02e01c0..2adada1a585517 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -583,6 +583,12 @@ static struct vmem_altmap *__nvdimm_setup_pfn(struct nd_pfn *nd_pfn, return altmap; } +static u64 phys_pmem_align_down(struct nd_pfn *nd_pfn, u64 phys) +{ + return min_t(u64, PHYS_SECTION_ALIGN_DOWN(phys), + ALIGN_DOWN(phys, nd_pfn->align)); +} + static int nd_pfn_init(struct nd_pfn *nd_pfn) { u32 dax_label_reserve = is_nd_dax(&nd_pfn->dev) ? SZ_128K : 0; @@ -638,13 +644,16 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn) 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) { + IORES_DESC_NONE) == REGION_MIXED + || !IS_ALIGNED(start + resource_size(&nsio->res), + nd_pfn->align)) { size = resource_size(&nsio->res); - end_trunc = start + size - PHYS_SECTION_ALIGN_DOWN(start + size); + end_trunc = start + size - phys_pmem_align_down(nd_pfn, + start + size); } if (start_pad + end_trunc) - dev_info(&nd_pfn->dev, "%s section collision, truncate %d bytes\n", + dev_info(&nd_pfn->dev, "%s alignment collision, truncate %d bytes\n", dev_name(&ndns->dev), start_pad + end_trunc); /* From 13b7954c0b8dd2d6382b4ddb5053f09e389d5c6e Mon Sep 17 00:00:00 2001 From: Vishal Verma Date: Thu, 14 Dec 2017 17:26:13 -0700 Subject: [PATCH 4/5] libnvdimm, btt: add a couple of missing kernel-doc lines Recent updates to btt.h neglected to add corresponding kernel-doc lines for new structure members. Add them. Signed-off-by: Vishal Verma Signed-off-by: Dan Williams --- drivers/nvdimm/btt.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/nvdimm/btt.h b/drivers/nvdimm/btt.h index 578c2057524d39..884fbbbdd18aa2 100644 --- a/drivers/nvdimm/btt.h +++ b/drivers/nvdimm/btt.h @@ -125,6 +125,7 @@ struct aligned_lock { * @list: List head for list of arenas * @debugfs_dir: Debugfs dentry * @flags: Arena flags - may signify error states. + * @err_lock: Mutex for synchronizing error clearing. * * arena_info is a per-arena handle. Once an arena is narrowed down for an * IO, this struct is passed around for the duration of the IO. @@ -176,6 +177,7 @@ struct arena_info { * @init_lock: Mutex used for the BTT initialization * @init_state: Flag describing the initialization state for the BTT * @num_arenas: Number of arenas in the BTT instance + * @phys_bb: Pointer to the namespace's badblocks structure */ struct btt { struct gendisk *btt_disk; From 24e3a7fb60a9187e5df90e5fa655ffc94b9c4f77 Mon Sep 17 00:00:00 2001 From: Vishal Verma Date: Mon, 18 Dec 2017 09:28:39 -0700 Subject: [PATCH 5/5] libnvdimm, btt: Fix an incompatibility in the log layout Due to a spec misinterpretation, the Linux implementation of the BTT log area had different padding scheme from other implementations, such as UEFI and NVML. This fixes the padding scheme, and defaults to it for new BTT layouts. We attempt to detect the padding scheme in use when probing for an existing BTT. If we detect the older/incompatible scheme, we continue using it. Reported-by: Juston Li Cc: Dan Williams Cc: Fixes: 5212e11fde4d ("nd_btt: atomic sector updates") Signed-off-by: Vishal Verma Signed-off-by: Dan Williams --- drivers/nvdimm/btt.c | 201 +++++++++++++++++++++++++++++++++++-------- drivers/nvdimm/btt.h | 45 +++++++++- 2 files changed, 211 insertions(+), 35 deletions(-) diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c index e949e3302af474..c586bcdb5190b1 100644 --- a/drivers/nvdimm/btt.c +++ b/drivers/nvdimm/btt.c @@ -211,12 +211,12 @@ static int btt_map_read(struct arena_info *arena, u32 lba, u32 *mapping, return ret; } -static int btt_log_read_pair(struct arena_info *arena, u32 lane, - struct log_entry *ent) +static int btt_log_group_read(struct arena_info *arena, u32 lane, + struct log_group *log) { return arena_read_bytes(arena, - arena->logoff + (2 * lane * LOG_ENT_SIZE), ent, - 2 * LOG_ENT_SIZE, 0); + arena->logoff + (lane * LOG_GRP_SIZE), log, + LOG_GRP_SIZE, 0); } static struct dentry *debugfs_root; @@ -256,6 +256,8 @@ static void arena_debugfs_init(struct arena_info *a, struct dentry *parent, debugfs_create_x64("logoff", S_IRUGO, d, &a->logoff); debugfs_create_x64("info2off", S_IRUGO, d, &a->info2off); debugfs_create_x32("flags", S_IRUGO, d, &a->flags); + debugfs_create_u32("log_index_0", S_IRUGO, d, &a->log_index[0]); + debugfs_create_u32("log_index_1", S_IRUGO, d, &a->log_index[1]); } static void btt_debugfs_init(struct btt *btt) @@ -274,6 +276,11 @@ static void btt_debugfs_init(struct btt *btt) } } +static u32 log_seq(struct log_group *log, int log_idx) +{ + return le32_to_cpu(log->ent[log_idx].seq); +} + /* * This function accepts two log entries, and uses the * sequence number to find the 'older' entry. @@ -283,8 +290,10 @@ static void btt_debugfs_init(struct btt *btt) * * TODO The logic feels a bit kludge-y. make it better.. */ -static int btt_log_get_old(struct log_entry *ent) +static int btt_log_get_old(struct arena_info *a, struct log_group *log) { + int idx0 = a->log_index[0]; + int idx1 = a->log_index[1]; int old; /* @@ -292,23 +301,23 @@ static int btt_log_get_old(struct log_entry *ent) * the next time, the following logic works out to put this * (next) entry into [1] */ - if (ent[0].seq == 0) { - ent[0].seq = cpu_to_le32(1); + if (log_seq(log, idx0) == 0) { + log->ent[idx0].seq = cpu_to_le32(1); return 0; } - if (ent[0].seq == ent[1].seq) + if (log_seq(log, idx0) == log_seq(log, idx1)) return -EINVAL; - if (le32_to_cpu(ent[0].seq) + le32_to_cpu(ent[1].seq) > 5) + if (log_seq(log, idx0) + log_seq(log, idx1) > 5) return -EINVAL; - if (le32_to_cpu(ent[0].seq) < le32_to_cpu(ent[1].seq)) { - if (le32_to_cpu(ent[1].seq) - le32_to_cpu(ent[0].seq) == 1) + if (log_seq(log, idx0) < log_seq(log, idx1)) { + if ((log_seq(log, idx1) - log_seq(log, idx0)) == 1) old = 0; else old = 1; } else { - if (le32_to_cpu(ent[0].seq) - le32_to_cpu(ent[1].seq) == 1) + if ((log_seq(log, idx0) - log_seq(log, idx1)) == 1) old = 1; else old = 0; @@ -328,17 +337,18 @@ static int btt_log_read(struct arena_info *arena, u32 lane, { int ret; int old_ent, ret_ent; - struct log_entry log[2]; + struct log_group log; - ret = btt_log_read_pair(arena, lane, log); + ret = btt_log_group_read(arena, lane, &log); if (ret) return -EIO; - old_ent = btt_log_get_old(log); + old_ent = btt_log_get_old(arena, &log); if (old_ent < 0 || old_ent > 1) { dev_err(to_dev(arena), "log corruption (%d): lane %d seq [%d, %d]\n", - old_ent, lane, log[0].seq, log[1].seq); + old_ent, lane, log.ent[arena->log_index[0]].seq, + log.ent[arena->log_index[1]].seq); /* TODO set error state? */ return -EIO; } @@ -346,7 +356,7 @@ static int btt_log_read(struct arena_info *arena, u32 lane, ret_ent = (old_flag ? old_ent : (1 - old_ent)); if (ent != NULL) - memcpy(ent, &log[ret_ent], LOG_ENT_SIZE); + memcpy(ent, &log.ent[arena->log_index[ret_ent]], LOG_ENT_SIZE); return ret_ent; } @@ -360,17 +370,13 @@ static int __btt_log_write(struct arena_info *arena, u32 lane, u32 sub, struct log_entry *ent, unsigned long flags) { int ret; - /* - * Ignore the padding in log_entry for calculating log_half. - * The entry is 'committed' when we write the sequence number, - * and we want to ensure that that is the last thing written. - * We don't bother writing the padding as that would be extra - * media wear and write amplification - */ - unsigned int log_half = (LOG_ENT_SIZE - 2 * sizeof(u64)) / 2; - u64 ns_off = arena->logoff + (((2 * lane) + sub) * LOG_ENT_SIZE); + u32 group_slot = arena->log_index[sub]; + unsigned int log_half = LOG_ENT_SIZE / 2; void *src = ent; + u64 ns_off; + ns_off = arena->logoff + (lane * LOG_GRP_SIZE) + + (group_slot * LOG_ENT_SIZE); /* split the 16B write into atomic, durable halves */ ret = arena_write_bytes(arena, ns_off, src, log_half, flags); if (ret) @@ -453,7 +459,7 @@ static int btt_log_init(struct arena_info *arena) { size_t logsize = arena->info2off - arena->logoff; size_t chunk_size = SZ_4K, offset = 0; - struct log_entry log; + struct log_entry ent; void *zerobuf; int ret; u32 i; @@ -485,11 +491,11 @@ static int btt_log_init(struct arena_info *arena) } for (i = 0; i < arena->nfree; i++) { - log.lba = cpu_to_le32(i); - log.old_map = cpu_to_le32(arena->external_nlba + i); - log.new_map = cpu_to_le32(arena->external_nlba + i); - log.seq = cpu_to_le32(LOG_SEQ_INIT); - ret = __btt_log_write(arena, i, 0, &log, 0); + ent.lba = cpu_to_le32(i); + ent.old_map = cpu_to_le32(arena->external_nlba + i); + ent.new_map = cpu_to_le32(arena->external_nlba + i); + ent.seq = cpu_to_le32(LOG_SEQ_INIT); + ret = __btt_log_write(arena, i, 0, &ent, 0); if (ret) goto free; } @@ -594,6 +600,123 @@ static int btt_freelist_init(struct arena_info *arena) return 0; } +static bool ent_is_padding(struct log_entry *ent) +{ + return (ent->lba == 0) && (ent->old_map == 0) && (ent->new_map == 0) + && (ent->seq == 0); +} + +/* + * Detecting valid log indices: We read a log group (see the comments in btt.h + * for a description of a 'log_group' and its 'slots'), and iterate over its + * four slots. We expect that a padding slot will be all-zeroes, and use this + * to detect a padding slot vs. an actual entry. + * + * If a log_group is in the initial state, i.e. hasn't been used since the + * creation of this BTT layout, it will have three of the four slots with + * zeroes. We skip over these log_groups for the detection of log_index. If + * all log_groups are in the initial state (i.e. the BTT has never been + * written to), it is safe to assume the 'new format' of log entries in slots + * (0, 1). + */ +static int log_set_indices(struct arena_info *arena) +{ + bool idx_set = false, initial_state = true; + int ret, log_index[2] = {-1, -1}; + u32 i, j, next_idx = 0; + struct log_group log; + u32 pad_count = 0; + + for (i = 0; i < arena->nfree; i++) { + ret = btt_log_group_read(arena, i, &log); + if (ret < 0) + return ret; + + for (j = 0; j < 4; j++) { + if (!idx_set) { + if (ent_is_padding(&log.ent[j])) { + pad_count++; + continue; + } else { + /* Skip if index has been recorded */ + if ((next_idx == 1) && + (j == log_index[0])) + continue; + /* valid entry, record index */ + log_index[next_idx] = j; + next_idx++; + } + if (next_idx == 2) { + /* two valid entries found */ + idx_set = true; + } else if (next_idx > 2) { + /* too many valid indices */ + return -ENXIO; + } + } else { + /* + * once the indices have been set, just verify + * that all subsequent log groups are either in + * their initial state or follow the same + * indices. + */ + if (j == log_index[0]) { + /* entry must be 'valid' */ + if (ent_is_padding(&log.ent[j])) + return -ENXIO; + } else if (j == log_index[1]) { + ; + /* + * log_index[1] can be padding if the + * lane never got used and it is still + * in the initial state (three 'padding' + * entries) + */ + } else { + /* entry must be invalid (padding) */ + if (!ent_is_padding(&log.ent[j])) + return -ENXIO; + } + } + } + /* + * If any of the log_groups have more than one valid, + * non-padding entry, then the we are no longer in the + * initial_state + */ + if (pad_count < 3) + initial_state = false; + pad_count = 0; + } + + if (!initial_state && !idx_set) + return -ENXIO; + + /* + * If all the entries in the log were in the initial state, + * assume new padding scheme + */ + if (initial_state) + log_index[1] = 1; + + /* + * Only allow the known permutations of log/padding indices, + * i.e. (0, 1), and (0, 2) + */ + if ((log_index[0] == 0) && ((log_index[1] == 1) || (log_index[1] == 2))) + ; /* known index possibilities */ + else { + dev_err(to_dev(arena), "Found an unknown padding scheme\n"); + return -ENXIO; + } + + arena->log_index[0] = log_index[0]; + arena->log_index[1] = log_index[1]; + dev_dbg(to_dev(arena), "log_index_0 = %d\n", log_index[0]); + dev_dbg(to_dev(arena), "log_index_1 = %d\n", log_index[1]); + return 0; +} + static int btt_rtt_init(struct arena_info *arena) { arena->rtt = kcalloc(arena->nfree, sizeof(u32), GFP_KERNEL); @@ -650,8 +773,7 @@ static struct arena_info *alloc_arena(struct btt *btt, size_t size, available -= 2 * BTT_PG_SIZE; /* The log takes a fixed amount of space based on nfree */ - logsize = roundup(2 * arena->nfree * sizeof(struct log_entry), - BTT_PG_SIZE); + logsize = roundup(arena->nfree * LOG_GRP_SIZE, BTT_PG_SIZE); available -= logsize; /* Calculate optimal split between map and data area */ @@ -668,6 +790,10 @@ static struct arena_info *alloc_arena(struct btt *btt, size_t size, arena->mapoff = arena->dataoff + datasize; arena->logoff = arena->mapoff + mapsize; arena->info2off = arena->logoff + logsize; + + /* Default log indices are (0,1) */ + arena->log_index[0] = 0; + arena->log_index[1] = 1; return arena; } @@ -758,6 +884,13 @@ static int discover_arenas(struct btt *btt) arena->external_lba_start = cur_nlba; parse_arena_meta(arena, super, cur_off); + ret = log_set_indices(arena); + if (ret) { + dev_err(to_dev(arena), + "Unable to deduce log/padding indices\n"); + goto out; + } + mutex_init(&arena->err_lock); ret = btt_freelist_init(arena); if (ret) diff --git a/drivers/nvdimm/btt.h b/drivers/nvdimm/btt.h index 884fbbbdd18aa2..db3cb6d4d0d495 100644 --- a/drivers/nvdimm/btt.h +++ b/drivers/nvdimm/btt.h @@ -27,6 +27,7 @@ #define MAP_ERR_MASK (1 << MAP_ERR_SHIFT) #define MAP_LBA_MASK (~((1 << MAP_TRIM_SHIFT) | (1 << MAP_ERR_SHIFT))) #define MAP_ENT_NORMAL 0xC0000000 +#define LOG_GRP_SIZE sizeof(struct log_group) #define LOG_ENT_SIZE sizeof(struct log_entry) #define ARENA_MIN_SIZE (1UL << 24) /* 16 MB */ #define ARENA_MAX_SIZE (1ULL << 39) /* 512 GB */ @@ -50,12 +51,52 @@ enum btt_init_state { INIT_READY }; +/* + * A log group represents one log 'lane', and consists of four log entries. + * Two of the four entries are valid entries, and the remaining two are + * padding. Due to an old bug in the padding location, we need to perform a + * test to determine the padding scheme being used, and use that scheme + * thereafter. + * + * In kernels prior to 4.15, 'log group' would have actual log entries at + * indices (0, 2) and padding at indices (1, 3), where as the correct/updated + * format has log entries at indices (0, 1) and padding at indices (2, 3). + * + * Old (pre 4.15) format: + * +-----------------+-----------------+ + * | ent[0] | ent[1] | + * | 16B | 16B | + * | lba/old/new/seq | pad | + * +-----------------------------------+ + * | ent[2] | ent[3] | + * | 16B | 16B | + * | lba/old/new/seq | pad | + * +-----------------+-----------------+ + * + * New format: + * +-----------------+-----------------+ + * | ent[0] | ent[1] | + * | 16B | 16B | + * | lba/old/new/seq | lba/old/new/seq | + * +-----------------------------------+ + * | ent[2] | ent[3] | + * | 16B | 16B | + * | pad | pad | + * +-----------------+-----------------+ + * + * We detect during start-up which format is in use, and set + * arena->log_index[(0, 1)] with the detected format. + */ + struct log_entry { __le32 lba; __le32 old_map; __le32 new_map; __le32 seq; - __le64 padding[2]; +}; + +struct log_group { + struct log_entry ent[4]; }; struct btt_sb { @@ -126,6 +167,7 @@ struct aligned_lock { * @debugfs_dir: Debugfs dentry * @flags: Arena flags - may signify error states. * @err_lock: Mutex for synchronizing error clearing. + * @log_index: Indices of the valid log entries in a log_group * * arena_info is a per-arena handle. Once an arena is narrowed down for an * IO, this struct is passed around for the duration of the IO. @@ -158,6 +200,7 @@ struct arena_info { /* Arena flags */ u32 flags; struct mutex err_lock; + int log_index[2]; }; /**