| /* |
| * Copyright(c) 2013-2015 Intel Corporation. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of version 2 of the GNU General Public License as |
| * published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| */ |
| #include <linux/device.h> |
| #include <linux/ndctl.h> |
| #include <linux/io.h> |
| #include <linux/nd.h> |
| #include "nd-core.h" |
| #include "label.h" |
| #include "nd.h" |
| |
| static u32 best_seq(u32 a, u32 b) |
| { |
| a &= NSINDEX_SEQ_MASK; |
| b &= NSINDEX_SEQ_MASK; |
| |
| if (a == 0 || a == b) |
| return b; |
| else if (b == 0) |
| return a; |
| else if (nd_inc_seq(a) == b) |
| return b; |
| else |
| return a; |
| } |
| |
| size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd) |
| { |
| u32 index_span; |
| |
| if (ndd->nsindex_size) |
| return ndd->nsindex_size; |
| |
| /* |
| * The minimum index space is 512 bytes, with that amount of |
| * index we can describe ~1400 labels which is less than a byte |
| * of overhead per label. Round up to a byte of overhead per |
| * label and determine the size of the index region. Yes, this |
| * starts to waste space at larger config_sizes, but it's |
| * unlikely we'll ever see anything but 128K. |
| */ |
| index_span = ndd->nsarea.config_size / 129; |
| index_span /= NSINDEX_ALIGN * 2; |
| ndd->nsindex_size = index_span * NSINDEX_ALIGN; |
| |
| return ndd->nsindex_size; |
| } |
| |
| int nd_label_validate(struct nvdimm_drvdata *ndd) |
| { |
| /* |
| * On media label format consists of two index blocks followed |
| * by an array of labels. None of these structures are ever |
| * updated in place. A sequence number tracks the current |
| * active index and the next one to write, while labels are |
| * written to free slots. |
| * |
| * +------------+ |
| * | | |
| * | nsindex0 | |
| * | | |
| * +------------+ |
| * | | |
| * | nsindex1 | |
| * | | |
| * +------------+ |
| * | label0 | |
| * +------------+ |
| * | label1 | |
| * +------------+ |
| * | | |
| * ....nslot... |
| * | | |
| * +------------+ |
| * | labelN | |
| * +------------+ |
| */ |
| struct nd_namespace_index *nsindex[] = { |
| to_namespace_index(ndd, 0), |
| to_namespace_index(ndd, 1), |
| }; |
| const int num_index = ARRAY_SIZE(nsindex); |
| struct device *dev = ndd->dev; |
| bool valid[2] = { 0 }; |
| int i, num_valid = 0; |
| u32 seq; |
| |
| for (i = 0; i < num_index; i++) { |
| u32 nslot; |
| u8 sig[NSINDEX_SIG_LEN]; |
| u64 sum_save, sum, size; |
| |
| memcpy(sig, nsindex[i]->sig, NSINDEX_SIG_LEN); |
| if (memcmp(sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN) != 0) { |
| dev_dbg(dev, "%s: nsindex%d signature invalid\n", |
| __func__, i); |
| continue; |
| } |
| sum_save = __le64_to_cpu(nsindex[i]->checksum); |
| nsindex[i]->checksum = __cpu_to_le64(0); |
| sum = nd_fletcher64(nsindex[i], sizeof_namespace_index(ndd), 1); |
| nsindex[i]->checksum = __cpu_to_le64(sum_save); |
| if (sum != sum_save) { |
| dev_dbg(dev, "%s: nsindex%d checksum invalid\n", |
| __func__, i); |
| continue; |
| } |
| |
| seq = __le32_to_cpu(nsindex[i]->seq); |
| if ((seq & NSINDEX_SEQ_MASK) == 0) { |
| dev_dbg(dev, "%s: nsindex%d sequence: %#x invalid\n", |
| __func__, i, seq); |
| continue; |
| } |
| |
| /* sanity check the index against expected values */ |
| if (__le64_to_cpu(nsindex[i]->myoff) |
| != i * sizeof_namespace_index(ndd)) { |
| dev_dbg(dev, "%s: nsindex%d myoff: %#llx invalid\n", |
| __func__, i, (unsigned long long) |
| __le64_to_cpu(nsindex[i]->myoff)); |
| continue; |
| } |
| if (__le64_to_cpu(nsindex[i]->otheroff) |
| != (!i) * sizeof_namespace_index(ndd)) { |
| dev_dbg(dev, "%s: nsindex%d otheroff: %#llx invalid\n", |
| __func__, i, (unsigned long long) |
| __le64_to_cpu(nsindex[i]->otheroff)); |
| continue; |
| } |
| |
| size = __le64_to_cpu(nsindex[i]->mysize); |
| if (size > sizeof_namespace_index(ndd) |
| || size < sizeof(struct nd_namespace_index)) { |
| dev_dbg(dev, "%s: nsindex%d mysize: %#llx invalid\n", |
| __func__, i, size); |
| continue; |
| } |
| |
| nslot = __le32_to_cpu(nsindex[i]->nslot); |
| if (nslot * sizeof(struct nd_namespace_label) |
| + 2 * sizeof_namespace_index(ndd) |
| > ndd->nsarea.config_size) { |
| dev_dbg(dev, "%s: nsindex%d nslot: %u invalid, config_size: %#x\n", |
| __func__, i, nslot, |
| ndd->nsarea.config_size); |
| continue; |
| } |
| valid[i] = true; |
| num_valid++; |
| } |
| |
| switch (num_valid) { |
| case 0: |
| break; |
| case 1: |
| for (i = 0; i < num_index; i++) |
| if (valid[i]) |
| return i; |
| /* can't have num_valid > 0 but valid[] = { false, false } */ |
| WARN_ON(1); |
| break; |
| default: |
| /* pick the best index... */ |
| seq = best_seq(__le32_to_cpu(nsindex[0]->seq), |
| __le32_to_cpu(nsindex[1]->seq)); |
| if (seq == (__le32_to_cpu(nsindex[1]->seq) & NSINDEX_SEQ_MASK)) |
| return 1; |
| else |
| return 0; |
| break; |
| } |
| |
| return -1; |
| } |
| |
| void nd_label_copy(struct nvdimm_drvdata *ndd, struct nd_namespace_index *dst, |
| struct nd_namespace_index *src) |
| { |
| if (dst && src) |
| /* pass */; |
| else |
| return; |
| |
| memcpy(dst, src, sizeof_namespace_index(ndd)); |
| } |
| |
| static struct nd_namespace_label *nd_label_base(struct nvdimm_drvdata *ndd) |
| { |
| void *base = to_namespace_index(ndd, 0); |
| |
| return base + 2 * sizeof_namespace_index(ndd); |
| } |
| |
| #define for_each_clear_bit_le(bit, addr, size) \ |
| for ((bit) = find_next_zero_bit_le((addr), (size), 0); \ |
| (bit) < (size); \ |
| (bit) = find_next_zero_bit_le((addr), (size), (bit) + 1)) |
| |
| /** |
| * preamble_current - common variable initialization for nd_label_* routines |
| * @ndd: dimm container for the relevant label set |
| * @nsindex_out: on return set to the currently active namespace index |
| * @free: on return set to the free label bitmap in the index |
| * @nslot: on return set to the number of slots in the label space |
| */ |
| static bool preamble_current(struct nvdimm_drvdata *ndd, |
| struct nd_namespace_index **nsindex_out, |
| unsigned long **free, u32 *nslot) |
| { |
| struct nd_namespace_index *nsindex; |
| |
| nsindex = to_current_namespace_index(ndd); |
| if (nsindex == NULL) |
| return false; |
| |
| *free = (unsigned long *) nsindex->free; |
| *nslot = __le32_to_cpu(nsindex->nslot); |
| *nsindex_out = nsindex; |
| |
| return true; |
| } |
| |
| char *nd_label_gen_id(struct nd_label_id *label_id, u8 *uuid, u32 flags) |
| { |
| if (!label_id || !uuid) |
| return NULL; |
| snprintf(label_id->id, ND_LABEL_ID_SIZE, "%s-%pUb", |
| flags & NSLABEL_FLAG_LOCAL ? "blk" : "pmem", uuid); |
| return label_id->id; |
| } |
| |
| static bool slot_valid(struct nd_namespace_label *nd_label, u32 slot) |
| { |
| /* check that we are written where we expect to be written */ |
| if (slot != __le32_to_cpu(nd_label->slot)) |
| return false; |
| |
| /* check that DPA allocations are page aligned */ |
| if ((__le64_to_cpu(nd_label->dpa) |
| | __le64_to_cpu(nd_label->rawsize)) % SZ_4K) |
| return false; |
| |
| return true; |
| } |
| |
| int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd) |
| { |
| struct nd_namespace_index *nsindex; |
| unsigned long *free; |
| u32 nslot, slot; |
| |
| if (!preamble_current(ndd, &nsindex, &free, &nslot)) |
| return 0; /* no label, nothing to reserve */ |
| |
| for_each_clear_bit_le(slot, free, nslot) { |
| struct nd_namespace_label *nd_label; |
| struct nd_region *nd_region = NULL; |
| u8 label_uuid[NSLABEL_UUID_LEN]; |
| struct nd_label_id label_id; |
| struct resource *res; |
| u32 flags; |
| |
| nd_label = nd_label_base(ndd) + slot; |
| |
| if (!slot_valid(nd_label, slot)) |
| continue; |
| |
| memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN); |
| flags = __le32_to_cpu(nd_label->flags); |
| nd_label_gen_id(&label_id, label_uuid, flags); |
| res = nvdimm_allocate_dpa(ndd, &label_id, |
| __le64_to_cpu(nd_label->dpa), |
| __le64_to_cpu(nd_label->rawsize)); |
| nd_dbg_dpa(nd_region, ndd, res, "reserve\n"); |
| if (!res) |
| return -EBUSY; |
| } |
| |
| return 0; |
| } |
| |
| int nd_label_active_count(struct nvdimm_drvdata *ndd) |
| { |
| struct nd_namespace_index *nsindex; |
| unsigned long *free; |
| u32 nslot, slot; |
| int count = 0; |
| |
| if (!preamble_current(ndd, &nsindex, &free, &nslot)) |
| return 0; |
| |
| for_each_clear_bit_le(slot, free, nslot) { |
| struct nd_namespace_label *nd_label; |
| |
| nd_label = nd_label_base(ndd) + slot; |
| |
| if (!slot_valid(nd_label, slot)) { |
| u32 label_slot = __le32_to_cpu(nd_label->slot); |
| u64 size = __le64_to_cpu(nd_label->rawsize); |
| u64 dpa = __le64_to_cpu(nd_label->dpa); |
| |
| dev_dbg(ndd->dev, |
| "%s: slot%d invalid slot: %d dpa: %llx size: %llx\n", |
| __func__, slot, label_slot, dpa, size); |
| continue; |
| } |
| count++; |
| } |
| return count; |
| } |
| |
| struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n) |
| { |
| struct nd_namespace_index *nsindex; |
| unsigned long *free; |
| u32 nslot, slot; |
| |
| if (!preamble_current(ndd, &nsindex, &free, &nslot)) |
| return NULL; |
| |
| for_each_clear_bit_le(slot, free, nslot) { |
| struct nd_namespace_label *nd_label; |
| |
| nd_label = nd_label_base(ndd) + slot; |
| if (!slot_valid(nd_label, slot)) |
| continue; |
| |
| if (n-- == 0) |
| return nd_label_base(ndd) + slot; |
| } |
| |
| return NULL; |
| } |