1175 lines
31 KiB
C
1175 lines
31 KiB
C
/*
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* Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of version 2 of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*/
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#include <linux/device.h>
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#include <linux/ndctl.h>
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#include <linux/uuid.h>
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#include <linux/slab.h>
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#include <linux/io.h>
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#include <linux/nd.h>
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#include "nd-core.h"
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#include "label.h"
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#include "nd.h"
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static guid_t nvdimm_btt_guid;
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static guid_t nvdimm_btt2_guid;
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static guid_t nvdimm_pfn_guid;
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static guid_t nvdimm_dax_guid;
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static u32 best_seq(u32 a, u32 b)
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{
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a &= NSINDEX_SEQ_MASK;
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b &= NSINDEX_SEQ_MASK;
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if (a == 0 || a == b)
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return b;
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else if (b == 0)
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return a;
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else if (nd_inc_seq(a) == b)
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return b;
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else
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return a;
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}
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unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd)
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{
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return ndd->nslabel_size;
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}
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int nvdimm_num_label_slots(struct nvdimm_drvdata *ndd)
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{
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return ndd->nsarea.config_size / (sizeof_namespace_label(ndd) + 1);
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}
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size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd)
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{
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u32 nslot, space, size;
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/*
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* The minimum index space is 512 bytes, with that amount of
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* index we can describe ~1400 labels which is less than a byte
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* of overhead per label. Round up to a byte of overhead per
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* label and determine the size of the index region. Yes, this
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* starts to waste space at larger config_sizes, but it's
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* unlikely we'll ever see anything but 128K.
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*/
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nslot = nvdimm_num_label_slots(ndd);
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space = ndd->nsarea.config_size - nslot * sizeof_namespace_label(ndd);
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size = ALIGN(sizeof(struct nd_namespace_index) + DIV_ROUND_UP(nslot, 8),
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NSINDEX_ALIGN) * 2;
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if (size <= space)
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return size / 2;
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dev_err(ndd->dev, "label area (%d) too small to host (%d byte) labels\n",
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ndd->nsarea.config_size, sizeof_namespace_label(ndd));
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return 0;
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}
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static int __nd_label_validate(struct nvdimm_drvdata *ndd)
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{
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/*
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* On media label format consists of two index blocks followed
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* by an array of labels. None of these structures are ever
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* updated in place. A sequence number tracks the current
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* active index and the next one to write, while labels are
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* written to free slots.
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*
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* +------------+
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* | |
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* | nsindex0 |
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* | |
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* +------------+
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* | |
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* | nsindex1 |
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* | |
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* +------------+
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* | label0 |
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* +------------+
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* | label1 |
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* +------------+
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* | |
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* ....nslot...
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* | |
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* +------------+
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* | labelN |
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* +------------+
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*/
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struct nd_namespace_index *nsindex[] = {
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to_namespace_index(ndd, 0),
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to_namespace_index(ndd, 1),
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};
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const int num_index = ARRAY_SIZE(nsindex);
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struct device *dev = ndd->dev;
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bool valid[2] = { 0 };
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int i, num_valid = 0;
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u32 seq;
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for (i = 0; i < num_index; i++) {
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u32 nslot;
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u8 sig[NSINDEX_SIG_LEN];
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u64 sum_save, sum, size;
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unsigned int version, labelsize;
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memcpy(sig, nsindex[i]->sig, NSINDEX_SIG_LEN);
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if (memcmp(sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN) != 0) {
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dev_dbg(dev, "%s: nsindex%d signature invalid\n",
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__func__, i);
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continue;
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}
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/* label sizes larger than 128 arrived with v1.2 */
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version = __le16_to_cpu(nsindex[i]->major) * 100
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+ __le16_to_cpu(nsindex[i]->minor);
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if (version >= 102)
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labelsize = 1 << (7 + nsindex[i]->labelsize);
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else
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labelsize = 128;
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if (labelsize != sizeof_namespace_label(ndd)) {
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dev_dbg(dev, "%s: nsindex%d labelsize %d invalid\n",
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__func__, i, nsindex[i]->labelsize);
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continue;
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}
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sum_save = __le64_to_cpu(nsindex[i]->checksum);
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nsindex[i]->checksum = __cpu_to_le64(0);
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sum = nd_fletcher64(nsindex[i], sizeof_namespace_index(ndd), 1);
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nsindex[i]->checksum = __cpu_to_le64(sum_save);
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if (sum != sum_save) {
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dev_dbg(dev, "%s: nsindex%d checksum invalid\n",
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__func__, i);
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continue;
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}
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seq = __le32_to_cpu(nsindex[i]->seq);
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if ((seq & NSINDEX_SEQ_MASK) == 0) {
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dev_dbg(dev, "%s: nsindex%d sequence: %#x invalid\n",
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__func__, i, seq);
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continue;
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}
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/* sanity check the index against expected values */
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if (__le64_to_cpu(nsindex[i]->myoff)
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!= i * sizeof_namespace_index(ndd)) {
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dev_dbg(dev, "%s: nsindex%d myoff: %#llx invalid\n",
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__func__, i, (unsigned long long)
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__le64_to_cpu(nsindex[i]->myoff));
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continue;
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}
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if (__le64_to_cpu(nsindex[i]->otheroff)
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!= (!i) * sizeof_namespace_index(ndd)) {
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dev_dbg(dev, "%s: nsindex%d otheroff: %#llx invalid\n",
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__func__, i, (unsigned long long)
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__le64_to_cpu(nsindex[i]->otheroff));
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continue;
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}
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size = __le64_to_cpu(nsindex[i]->mysize);
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if (size > sizeof_namespace_index(ndd)
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|| size < sizeof(struct nd_namespace_index)) {
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dev_dbg(dev, "%s: nsindex%d mysize: %#llx invalid\n",
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__func__, i, size);
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continue;
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}
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nslot = __le32_to_cpu(nsindex[i]->nslot);
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if (nslot * sizeof_namespace_label(ndd)
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+ 2 * sizeof_namespace_index(ndd)
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> ndd->nsarea.config_size) {
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dev_dbg(dev, "%s: nsindex%d nslot: %u invalid, config_size: %#x\n",
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__func__, i, nslot,
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ndd->nsarea.config_size);
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continue;
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}
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valid[i] = true;
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num_valid++;
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}
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switch (num_valid) {
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case 0:
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break;
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case 1:
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for (i = 0; i < num_index; i++)
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if (valid[i])
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return i;
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/* can't have num_valid > 0 but valid[] = { false, false } */
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WARN_ON(1);
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break;
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default:
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/* pick the best index... */
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seq = best_seq(__le32_to_cpu(nsindex[0]->seq),
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__le32_to_cpu(nsindex[1]->seq));
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if (seq == (__le32_to_cpu(nsindex[1]->seq) & NSINDEX_SEQ_MASK))
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return 1;
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else
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return 0;
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break;
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}
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return -1;
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}
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int nd_label_validate(struct nvdimm_drvdata *ndd)
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{
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/*
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* In order to probe for and validate namespace index blocks we
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* need to know the size of the labels, and we can't trust the
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* size of the labels until we validate the index blocks.
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* Resolve this dependency loop by probing for known label
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* sizes, but default to v1.2 256-byte namespace labels if
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* discovery fails.
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*/
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int label_size[] = { 128, 256 };
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int i, rc;
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for (i = 0; i < ARRAY_SIZE(label_size); i++) {
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ndd->nslabel_size = label_size[i];
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rc = __nd_label_validate(ndd);
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if (rc >= 0)
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return rc;
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}
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return -1;
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}
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void nd_label_copy(struct nvdimm_drvdata *ndd, struct nd_namespace_index *dst,
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struct nd_namespace_index *src)
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{
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if (dst && src)
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/* pass */;
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else
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return;
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memcpy(dst, src, sizeof_namespace_index(ndd));
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}
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static struct nd_namespace_label *nd_label_base(struct nvdimm_drvdata *ndd)
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{
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void *base = to_namespace_index(ndd, 0);
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return base + 2 * sizeof_namespace_index(ndd);
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}
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static int to_slot(struct nvdimm_drvdata *ndd,
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struct nd_namespace_label *nd_label)
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{
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unsigned long label, base;
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label = (unsigned long) nd_label;
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base = (unsigned long) nd_label_base(ndd);
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return (label - base) / sizeof_namespace_label(ndd);
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}
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static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
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{
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unsigned long label, base;
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base = (unsigned long) nd_label_base(ndd);
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label = base + sizeof_namespace_label(ndd) * slot;
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return (struct nd_namespace_label *) label;
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}
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#define for_each_clear_bit_le(bit, addr, size) \
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for ((bit) = find_next_zero_bit_le((addr), (size), 0); \
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(bit) < (size); \
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(bit) = find_next_zero_bit_le((addr), (size), (bit) + 1))
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/**
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* preamble_index - common variable initialization for nd_label_* routines
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* @ndd: dimm container for the relevant label set
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* @idx: namespace_index index
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* @nsindex_out: on return set to the currently active namespace index
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* @free: on return set to the free label bitmap in the index
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* @nslot: on return set to the number of slots in the label space
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*/
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static bool preamble_index(struct nvdimm_drvdata *ndd, int idx,
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struct nd_namespace_index **nsindex_out,
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unsigned long **free, u32 *nslot)
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{
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struct nd_namespace_index *nsindex;
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nsindex = to_namespace_index(ndd, idx);
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if (nsindex == NULL)
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return false;
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*free = (unsigned long *) nsindex->free;
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*nslot = __le32_to_cpu(nsindex->nslot);
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*nsindex_out = nsindex;
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return true;
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}
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char *nd_label_gen_id(struct nd_label_id *label_id, u8 *uuid, u32 flags)
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{
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if (!label_id || !uuid)
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return NULL;
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snprintf(label_id->id, ND_LABEL_ID_SIZE, "%s-%pUb",
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flags & NSLABEL_FLAG_LOCAL ? "blk" : "pmem", uuid);
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return label_id->id;
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}
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static bool preamble_current(struct nvdimm_drvdata *ndd,
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struct nd_namespace_index **nsindex,
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unsigned long **free, u32 *nslot)
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{
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return preamble_index(ndd, ndd->ns_current, nsindex,
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free, nslot);
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}
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static bool preamble_next(struct nvdimm_drvdata *ndd,
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struct nd_namespace_index **nsindex,
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unsigned long **free, u32 *nslot)
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{
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return preamble_index(ndd, ndd->ns_next, nsindex,
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free, nslot);
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}
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static bool slot_valid(struct nvdimm_drvdata *ndd,
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struct nd_namespace_label *nd_label, u32 slot)
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{
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/* check that we are written where we expect to be written */
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if (slot != __le32_to_cpu(nd_label->slot))
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return false;
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/* check that DPA allocations are page aligned */
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if ((__le64_to_cpu(nd_label->dpa)
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| __le64_to_cpu(nd_label->rawsize)) % SZ_4K)
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return false;
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/* check checksum */
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if (namespace_label_has(ndd, checksum)) {
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u64 sum, sum_save;
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sum_save = __le64_to_cpu(nd_label->checksum);
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nd_label->checksum = __cpu_to_le64(0);
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sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
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nd_label->checksum = __cpu_to_le64(sum_save);
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if (sum != sum_save) {
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dev_dbg(ndd->dev, "%s fail checksum. slot: %d expect: %#llx\n",
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__func__, slot, sum);
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return false;
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}
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}
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return true;
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}
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int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
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{
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struct nd_namespace_index *nsindex;
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unsigned long *free;
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u32 nslot, slot;
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if (!preamble_current(ndd, &nsindex, &free, &nslot))
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return 0; /* no label, nothing to reserve */
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for_each_clear_bit_le(slot, free, nslot) {
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struct nd_namespace_label *nd_label;
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struct nd_region *nd_region = NULL;
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u8 label_uuid[NSLABEL_UUID_LEN];
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struct nd_label_id label_id;
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struct resource *res;
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u32 flags;
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nd_label = to_label(ndd, slot);
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if (!slot_valid(ndd, nd_label, slot))
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continue;
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memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
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flags = __le32_to_cpu(nd_label->flags);
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nd_label_gen_id(&label_id, label_uuid, flags);
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res = nvdimm_allocate_dpa(ndd, &label_id,
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__le64_to_cpu(nd_label->dpa),
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__le64_to_cpu(nd_label->rawsize));
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nd_dbg_dpa(nd_region, ndd, res, "reserve\n");
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if (!res)
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return -EBUSY;
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}
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return 0;
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}
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int nd_label_active_count(struct nvdimm_drvdata *ndd)
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{
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struct nd_namespace_index *nsindex;
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unsigned long *free;
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u32 nslot, slot;
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int count = 0;
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if (!preamble_current(ndd, &nsindex, &free, &nslot))
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return 0;
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for_each_clear_bit_le(slot, free, nslot) {
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struct nd_namespace_label *nd_label;
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nd_label = to_label(ndd, slot);
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if (!slot_valid(ndd, nd_label, slot)) {
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u32 label_slot = __le32_to_cpu(nd_label->slot);
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u64 size = __le64_to_cpu(nd_label->rawsize);
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u64 dpa = __le64_to_cpu(nd_label->dpa);
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dev_dbg(ndd->dev,
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"%s: slot%d invalid slot: %d dpa: %llx size: %llx\n",
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__func__, slot, label_slot, dpa, size);
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continue;
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}
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count++;
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}
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return count;
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}
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struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
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{
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struct nd_namespace_index *nsindex;
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unsigned long *free;
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u32 nslot, slot;
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if (!preamble_current(ndd, &nsindex, &free, &nslot))
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return NULL;
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for_each_clear_bit_le(slot, free, nslot) {
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struct nd_namespace_label *nd_label;
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nd_label = to_label(ndd, slot);
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if (!slot_valid(ndd, nd_label, slot))
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continue;
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if (n-- == 0)
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return to_label(ndd, slot);
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}
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return NULL;
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}
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u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd)
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{
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struct nd_namespace_index *nsindex;
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unsigned long *free;
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u32 nslot, slot;
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if (!preamble_next(ndd, &nsindex, &free, &nslot))
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return UINT_MAX;
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WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
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slot = find_next_bit_le(free, nslot, 0);
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if (slot == nslot)
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return UINT_MAX;
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clear_bit_le(slot, free);
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return slot;
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}
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bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot)
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{
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struct nd_namespace_index *nsindex;
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unsigned long *free;
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u32 nslot;
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if (!preamble_next(ndd, &nsindex, &free, &nslot))
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return false;
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WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
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if (slot < nslot)
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return !test_and_set_bit_le(slot, free);
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return false;
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}
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u32 nd_label_nfree(struct nvdimm_drvdata *ndd)
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{
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struct nd_namespace_index *nsindex;
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unsigned long *free;
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u32 nslot;
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WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
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if (!preamble_next(ndd, &nsindex, &free, &nslot))
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return nvdimm_num_label_slots(ndd);
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return bitmap_weight(free, nslot);
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}
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static int nd_label_write_index(struct nvdimm_drvdata *ndd, int index, u32 seq,
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unsigned long flags)
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{
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struct nd_namespace_index *nsindex;
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unsigned long offset;
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u64 checksum;
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u32 nslot;
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|
int rc;
|
|
|
|
nsindex = to_namespace_index(ndd, index);
|
|
if (flags & ND_NSINDEX_INIT)
|
|
nslot = nvdimm_num_label_slots(ndd);
|
|
else
|
|
nslot = __le32_to_cpu(nsindex->nslot);
|
|
|
|
memcpy(nsindex->sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN);
|
|
memset(&nsindex->flags, 0, 3);
|
|
nsindex->labelsize = sizeof_namespace_label(ndd) >> 8;
|
|
nsindex->seq = __cpu_to_le32(seq);
|
|
offset = (unsigned long) nsindex
|
|
- (unsigned long) to_namespace_index(ndd, 0);
|
|
nsindex->myoff = __cpu_to_le64(offset);
|
|
nsindex->mysize = __cpu_to_le64(sizeof_namespace_index(ndd));
|
|
offset = (unsigned long) to_namespace_index(ndd,
|
|
nd_label_next_nsindex(index))
|
|
- (unsigned long) to_namespace_index(ndd, 0);
|
|
nsindex->otheroff = __cpu_to_le64(offset);
|
|
offset = (unsigned long) nd_label_base(ndd)
|
|
- (unsigned long) to_namespace_index(ndd, 0);
|
|
nsindex->labeloff = __cpu_to_le64(offset);
|
|
nsindex->nslot = __cpu_to_le32(nslot);
|
|
nsindex->major = __cpu_to_le16(1);
|
|
if (sizeof_namespace_label(ndd) < 256)
|
|
nsindex->minor = __cpu_to_le16(1);
|
|
else
|
|
nsindex->minor = __cpu_to_le16(2);
|
|
nsindex->checksum = __cpu_to_le64(0);
|
|
if (flags & ND_NSINDEX_INIT) {
|
|
unsigned long *free = (unsigned long *) nsindex->free;
|
|
u32 nfree = ALIGN(nslot, BITS_PER_LONG);
|
|
int last_bits, i;
|
|
|
|
memset(nsindex->free, 0xff, nfree / 8);
|
|
for (i = 0, last_bits = nfree - nslot; i < last_bits; i++)
|
|
clear_bit_le(nslot + i, free);
|
|
}
|
|
checksum = nd_fletcher64(nsindex, sizeof_namespace_index(ndd), 1);
|
|
nsindex->checksum = __cpu_to_le64(checksum);
|
|
rc = nvdimm_set_config_data(ndd, __le64_to_cpu(nsindex->myoff),
|
|
nsindex, sizeof_namespace_index(ndd));
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
if (flags & ND_NSINDEX_INIT)
|
|
return 0;
|
|
|
|
/* copy the index we just wrote to the new 'next' */
|
|
WARN_ON(index != ndd->ns_next);
|
|
nd_label_copy(ndd, to_current_namespace_index(ndd), nsindex);
|
|
ndd->ns_current = nd_label_next_nsindex(ndd->ns_current);
|
|
ndd->ns_next = nd_label_next_nsindex(ndd->ns_next);
|
|
WARN_ON(ndd->ns_current == ndd->ns_next);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd,
|
|
struct nd_namespace_label *nd_label)
|
|
{
|
|
return (unsigned long) nd_label
|
|
- (unsigned long) to_namespace_index(ndd, 0);
|
|
}
|
|
|
|
enum nvdimm_claim_class to_nvdimm_cclass(guid_t *guid)
|
|
{
|
|
if (guid_equal(guid, &nvdimm_btt_guid))
|
|
return NVDIMM_CCLASS_BTT;
|
|
else if (guid_equal(guid, &nvdimm_btt2_guid))
|
|
return NVDIMM_CCLASS_BTT2;
|
|
else if (guid_equal(guid, &nvdimm_pfn_guid))
|
|
return NVDIMM_CCLASS_PFN;
|
|
else if (guid_equal(guid, &nvdimm_dax_guid))
|
|
return NVDIMM_CCLASS_DAX;
|
|
else if (guid_equal(guid, &guid_null))
|
|
return NVDIMM_CCLASS_NONE;
|
|
|
|
return NVDIMM_CCLASS_UNKNOWN;
|
|
}
|
|
|
|
static const guid_t *to_abstraction_guid(enum nvdimm_claim_class claim_class,
|
|
guid_t *target)
|
|
{
|
|
if (claim_class == NVDIMM_CCLASS_BTT)
|
|
return &nvdimm_btt_guid;
|
|
else if (claim_class == NVDIMM_CCLASS_BTT2)
|
|
return &nvdimm_btt2_guid;
|
|
else if (claim_class == NVDIMM_CCLASS_PFN)
|
|
return &nvdimm_pfn_guid;
|
|
else if (claim_class == NVDIMM_CCLASS_DAX)
|
|
return &nvdimm_dax_guid;
|
|
else if (claim_class == NVDIMM_CCLASS_UNKNOWN) {
|
|
/*
|
|
* If we're modifying a namespace for which we don't
|
|
* know the claim_class, don't touch the existing guid.
|
|
*/
|
|
return target;
|
|
} else
|
|
return &guid_null;
|
|
}
|
|
|
|
static int __pmem_label_update(struct nd_region *nd_region,
|
|
struct nd_mapping *nd_mapping, struct nd_namespace_pmem *nspm,
|
|
int pos)
|
|
{
|
|
struct nd_namespace_common *ndns = &nspm->nsio.common;
|
|
struct nd_interleave_set *nd_set = nd_region->nd_set;
|
|
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
|
|
struct nd_label_ent *label_ent, *victim = NULL;
|
|
struct nd_namespace_label *nd_label;
|
|
struct nd_namespace_index *nsindex;
|
|
struct nd_label_id label_id;
|
|
struct resource *res;
|
|
unsigned long *free;
|
|
u32 nslot, slot;
|
|
size_t offset;
|
|
u64 cookie;
|
|
int rc;
|
|
|
|
if (!preamble_next(ndd, &nsindex, &free, &nslot))
|
|
return -ENXIO;
|
|
|
|
cookie = nd_region_interleave_set_cookie(nd_region, nsindex);
|
|
nd_label_gen_id(&label_id, nspm->uuid, 0);
|
|
for_each_dpa_resource(ndd, res)
|
|
if (strcmp(res->name, label_id.id) == 0)
|
|
break;
|
|
|
|
if (!res) {
|
|
WARN_ON_ONCE(1);
|
|
return -ENXIO;
|
|
}
|
|
|
|
/* allocate and write the label to the staging (next) index */
|
|
slot = nd_label_alloc_slot(ndd);
|
|
if (slot == UINT_MAX)
|
|
return -ENXIO;
|
|
dev_dbg(ndd->dev, "%s: allocated: %d\n", __func__, slot);
|
|
|
|
nd_label = to_label(ndd, slot);
|
|
memset(nd_label, 0, sizeof_namespace_label(ndd));
|
|
memcpy(nd_label->uuid, nspm->uuid, NSLABEL_UUID_LEN);
|
|
if (nspm->alt_name)
|
|
memcpy(nd_label->name, nspm->alt_name, NSLABEL_NAME_LEN);
|
|
nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_UPDATING);
|
|
nd_label->nlabel = __cpu_to_le16(nd_region->ndr_mappings);
|
|
nd_label->position = __cpu_to_le16(pos);
|
|
nd_label->isetcookie = __cpu_to_le64(cookie);
|
|
nd_label->rawsize = __cpu_to_le64(resource_size(res));
|
|
nd_label->lbasize = __cpu_to_le64(nspm->lbasize);
|
|
nd_label->dpa = __cpu_to_le64(res->start);
|
|
nd_label->slot = __cpu_to_le32(slot);
|
|
if (namespace_label_has(ndd, type_guid))
|
|
guid_copy(&nd_label->type_guid, &nd_set->type_guid);
|
|
if (namespace_label_has(ndd, abstraction_guid))
|
|
guid_copy(&nd_label->abstraction_guid,
|
|
to_abstraction_guid(ndns->claim_class,
|
|
&nd_label->abstraction_guid));
|
|
if (namespace_label_has(ndd, checksum)) {
|
|
u64 sum;
|
|
|
|
nd_label->checksum = __cpu_to_le64(0);
|
|
sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
|
|
nd_label->checksum = __cpu_to_le64(sum);
|
|
}
|
|
nd_dbg_dpa(nd_region, ndd, res, "%s\n", __func__);
|
|
|
|
/* update label */
|
|
offset = nd_label_offset(ndd, nd_label);
|
|
rc = nvdimm_set_config_data(ndd, offset, nd_label,
|
|
sizeof_namespace_label(ndd));
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
/* Garbage collect the previous label */
|
|
mutex_lock(&nd_mapping->lock);
|
|
list_for_each_entry(label_ent, &nd_mapping->labels, list) {
|
|
if (!label_ent->label)
|
|
continue;
|
|
if (memcmp(nspm->uuid, label_ent->label->uuid,
|
|
NSLABEL_UUID_LEN) != 0)
|
|
continue;
|
|
victim = label_ent;
|
|
list_move_tail(&victim->list, &nd_mapping->labels);
|
|
break;
|
|
}
|
|
if (victim) {
|
|
dev_dbg(ndd->dev, "%s: free: %d\n", __func__, slot);
|
|
slot = to_slot(ndd, victim->label);
|
|
nd_label_free_slot(ndd, slot);
|
|
victim->label = NULL;
|
|
}
|
|
|
|
/* update index */
|
|
rc = nd_label_write_index(ndd, ndd->ns_next,
|
|
nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
|
|
if (rc == 0) {
|
|
list_for_each_entry(label_ent, &nd_mapping->labels, list)
|
|
if (!label_ent->label) {
|
|
label_ent->label = nd_label;
|
|
nd_label = NULL;
|
|
break;
|
|
}
|
|
dev_WARN_ONCE(&nspm->nsio.common.dev, nd_label,
|
|
"failed to track label: %d\n",
|
|
to_slot(ndd, nd_label));
|
|
if (nd_label)
|
|
rc = -ENXIO;
|
|
}
|
|
mutex_unlock(&nd_mapping->lock);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static bool is_old_resource(struct resource *res, struct resource **list, int n)
|
|
{
|
|
int i;
|
|
|
|
if (res->flags & DPA_RESOURCE_ADJUSTED)
|
|
return false;
|
|
for (i = 0; i < n; i++)
|
|
if (res == list[i])
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static struct resource *to_resource(struct nvdimm_drvdata *ndd,
|
|
struct nd_namespace_label *nd_label)
|
|
{
|
|
struct resource *res;
|
|
|
|
for_each_dpa_resource(ndd, res) {
|
|
if (res->start != __le64_to_cpu(nd_label->dpa))
|
|
continue;
|
|
if (resource_size(res) != __le64_to_cpu(nd_label->rawsize))
|
|
continue;
|
|
return res;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* 1/ Account all the labels that can be freed after this update
|
|
* 2/ Allocate and write the label to the staging (next) index
|
|
* 3/ Record the resources in the namespace device
|
|
*/
|
|
static int __blk_label_update(struct nd_region *nd_region,
|
|
struct nd_mapping *nd_mapping, struct nd_namespace_blk *nsblk,
|
|
int num_labels)
|
|
{
|
|
int i, alloc, victims, nfree, old_num_resources, nlabel, rc = -ENXIO;
|
|
struct nd_interleave_set *nd_set = nd_region->nd_set;
|
|
struct nd_namespace_common *ndns = &nsblk->common;
|
|
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
|
|
struct nd_namespace_label *nd_label;
|
|
struct nd_label_ent *label_ent, *e;
|
|
struct nd_namespace_index *nsindex;
|
|
unsigned long *free, *victim_map = NULL;
|
|
struct resource *res, **old_res_list;
|
|
struct nd_label_id label_id;
|
|
u8 uuid[NSLABEL_UUID_LEN];
|
|
int min_dpa_idx = 0;
|
|
LIST_HEAD(list);
|
|
u32 nslot, slot;
|
|
|
|
if (!preamble_next(ndd, &nsindex, &free, &nslot))
|
|
return -ENXIO;
|
|
|
|
old_res_list = nsblk->res;
|
|
nfree = nd_label_nfree(ndd);
|
|
old_num_resources = nsblk->num_resources;
|
|
nd_label_gen_id(&label_id, nsblk->uuid, NSLABEL_FLAG_LOCAL);
|
|
|
|
/*
|
|
* We need to loop over the old resources a few times, which seems a
|
|
* bit inefficient, but we need to know that we have the label
|
|
* space before we start mutating the tracking structures.
|
|
* Otherwise the recovery method of last resort for userspace is
|
|
* disable and re-enable the parent region.
|
|
*/
|
|
alloc = 0;
|
|
for_each_dpa_resource(ndd, res) {
|
|
if (strcmp(res->name, label_id.id) != 0)
|
|
continue;
|
|
if (!is_old_resource(res, old_res_list, old_num_resources))
|
|
alloc++;
|
|
}
|
|
|
|
victims = 0;
|
|
if (old_num_resources) {
|
|
/* convert old local-label-map to dimm-slot victim-map */
|
|
victim_map = kcalloc(BITS_TO_LONGS(nslot), sizeof(long),
|
|
GFP_KERNEL);
|
|
if (!victim_map)
|
|
return -ENOMEM;
|
|
|
|
/* mark unused labels for garbage collection */
|
|
for_each_clear_bit_le(slot, free, nslot) {
|
|
nd_label = to_label(ndd, slot);
|
|
memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
|
|
if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
|
|
continue;
|
|
res = to_resource(ndd, nd_label);
|
|
if (res && is_old_resource(res, old_res_list,
|
|
old_num_resources))
|
|
continue;
|
|
slot = to_slot(ndd, nd_label);
|
|
set_bit(slot, victim_map);
|
|
victims++;
|
|
}
|
|
}
|
|
|
|
/* don't allow updates that consume the last label */
|
|
if (nfree - alloc < 0 || nfree - alloc + victims < 1) {
|
|
dev_info(&nsblk->common.dev, "insufficient label space\n");
|
|
kfree(victim_map);
|
|
return -ENOSPC;
|
|
}
|
|
/* from here on we need to abort on error */
|
|
|
|
|
|
/* assign all resources to the namespace before writing the labels */
|
|
nsblk->res = NULL;
|
|
nsblk->num_resources = 0;
|
|
for_each_dpa_resource(ndd, res) {
|
|
if (strcmp(res->name, label_id.id) != 0)
|
|
continue;
|
|
if (!nsblk_add_resource(nd_region, ndd, nsblk, res->start)) {
|
|
rc = -ENOMEM;
|
|
goto abort;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Find the resource associated with the first label in the set
|
|
* per the v1.2 namespace specification.
|
|
*/
|
|
for (i = 0; i < nsblk->num_resources; i++) {
|
|
struct resource *min = nsblk->res[min_dpa_idx];
|
|
|
|
res = nsblk->res[i];
|
|
if (res->start < min->start)
|
|
min_dpa_idx = i;
|
|
}
|
|
|
|
for (i = 0; i < nsblk->num_resources; i++) {
|
|
size_t offset;
|
|
|
|
res = nsblk->res[i];
|
|
if (is_old_resource(res, old_res_list, old_num_resources))
|
|
continue; /* carry-over */
|
|
slot = nd_label_alloc_slot(ndd);
|
|
if (slot == UINT_MAX)
|
|
goto abort;
|
|
dev_dbg(ndd->dev, "%s: allocated: %d\n", __func__, slot);
|
|
|
|
nd_label = to_label(ndd, slot);
|
|
memset(nd_label, 0, sizeof_namespace_label(ndd));
|
|
memcpy(nd_label->uuid, nsblk->uuid, NSLABEL_UUID_LEN);
|
|
if (nsblk->alt_name)
|
|
memcpy(nd_label->name, nsblk->alt_name,
|
|
NSLABEL_NAME_LEN);
|
|
nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_LOCAL);
|
|
|
|
/*
|
|
* Use the presence of the type_guid as a flag to
|
|
* determine isetcookie usage and nlabel + position
|
|
* policy for blk-aperture namespaces.
|
|
*/
|
|
if (namespace_label_has(ndd, type_guid)) {
|
|
if (i == min_dpa_idx) {
|
|
nd_label->nlabel = __cpu_to_le16(nsblk->num_resources);
|
|
nd_label->position = __cpu_to_le16(0);
|
|
} else {
|
|
nd_label->nlabel = __cpu_to_le16(0xffff);
|
|
nd_label->position = __cpu_to_le16(0xffff);
|
|
}
|
|
nd_label->isetcookie = __cpu_to_le64(nd_set->cookie2);
|
|
} else {
|
|
nd_label->nlabel = __cpu_to_le16(0); /* N/A */
|
|
nd_label->position = __cpu_to_le16(0); /* N/A */
|
|
nd_label->isetcookie = __cpu_to_le64(0); /* N/A */
|
|
}
|
|
|
|
nd_label->dpa = __cpu_to_le64(res->start);
|
|
nd_label->rawsize = __cpu_to_le64(resource_size(res));
|
|
nd_label->lbasize = __cpu_to_le64(nsblk->lbasize);
|
|
nd_label->slot = __cpu_to_le32(slot);
|
|
if (namespace_label_has(ndd, type_guid))
|
|
guid_copy(&nd_label->type_guid, &nd_set->type_guid);
|
|
if (namespace_label_has(ndd, abstraction_guid))
|
|
guid_copy(&nd_label->abstraction_guid,
|
|
to_abstraction_guid(ndns->claim_class,
|
|
&nd_label->abstraction_guid));
|
|
|
|
if (namespace_label_has(ndd, checksum)) {
|
|
u64 sum;
|
|
|
|
nd_label->checksum = __cpu_to_le64(0);
|
|
sum = nd_fletcher64(nd_label,
|
|
sizeof_namespace_label(ndd), 1);
|
|
nd_label->checksum = __cpu_to_le64(sum);
|
|
}
|
|
|
|
/* update label */
|
|
offset = nd_label_offset(ndd, nd_label);
|
|
rc = nvdimm_set_config_data(ndd, offset, nd_label,
|
|
sizeof_namespace_label(ndd));
|
|
if (rc < 0)
|
|
goto abort;
|
|
}
|
|
|
|
/* free up now unused slots in the new index */
|
|
for_each_set_bit(slot, victim_map, victim_map ? nslot : 0) {
|
|
dev_dbg(ndd->dev, "%s: free: %d\n", __func__, slot);
|
|
nd_label_free_slot(ndd, slot);
|
|
}
|
|
|
|
/* update index */
|
|
rc = nd_label_write_index(ndd, ndd->ns_next,
|
|
nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
|
|
if (rc)
|
|
goto abort;
|
|
|
|
/*
|
|
* Now that the on-dimm labels are up to date, fix up the tracking
|
|
* entries in nd_mapping->labels
|
|
*/
|
|
nlabel = 0;
|
|
mutex_lock(&nd_mapping->lock);
|
|
list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
|
|
nd_label = label_ent->label;
|
|
if (!nd_label)
|
|
continue;
|
|
nlabel++;
|
|
memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
|
|
if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
|
|
continue;
|
|
nlabel--;
|
|
list_move(&label_ent->list, &list);
|
|
label_ent->label = NULL;
|
|
}
|
|
list_splice_tail_init(&list, &nd_mapping->labels);
|
|
mutex_unlock(&nd_mapping->lock);
|
|
|
|
if (nlabel + nsblk->num_resources > num_labels) {
|
|
/*
|
|
* Bug, we can't end up with more resources than
|
|
* available labels
|
|
*/
|
|
WARN_ON_ONCE(1);
|
|
rc = -ENXIO;
|
|
goto out;
|
|
}
|
|
|
|
mutex_lock(&nd_mapping->lock);
|
|
label_ent = list_first_entry_or_null(&nd_mapping->labels,
|
|
typeof(*label_ent), list);
|
|
if (!label_ent) {
|
|
WARN_ON(1);
|
|
mutex_unlock(&nd_mapping->lock);
|
|
rc = -ENXIO;
|
|
goto out;
|
|
}
|
|
for_each_clear_bit_le(slot, free, nslot) {
|
|
nd_label = to_label(ndd, slot);
|
|
memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
|
|
if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
|
|
continue;
|
|
res = to_resource(ndd, nd_label);
|
|
res->flags &= ~DPA_RESOURCE_ADJUSTED;
|
|
dev_vdbg(&nsblk->common.dev, "assign label slot: %d\n", slot);
|
|
list_for_each_entry_from(label_ent, &nd_mapping->labels, list) {
|
|
if (label_ent->label)
|
|
continue;
|
|
label_ent->label = nd_label;
|
|
nd_label = NULL;
|
|
break;
|
|
}
|
|
if (nd_label)
|
|
dev_WARN(&nsblk->common.dev,
|
|
"failed to track label slot%d\n", slot);
|
|
}
|
|
mutex_unlock(&nd_mapping->lock);
|
|
|
|
out:
|
|
kfree(old_res_list);
|
|
kfree(victim_map);
|
|
return rc;
|
|
|
|
abort:
|
|
/*
|
|
* 1/ repair the allocated label bitmap in the index
|
|
* 2/ restore the resource list
|
|
*/
|
|
nd_label_copy(ndd, nsindex, to_current_namespace_index(ndd));
|
|
kfree(nsblk->res);
|
|
nsblk->res = old_res_list;
|
|
nsblk->num_resources = old_num_resources;
|
|
old_res_list = NULL;
|
|
goto out;
|
|
}
|
|
|
|
static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
|
|
{
|
|
int i, old_num_labels = 0;
|
|
struct nd_label_ent *label_ent;
|
|
struct nd_namespace_index *nsindex;
|
|
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
|
|
|
|
mutex_lock(&nd_mapping->lock);
|
|
list_for_each_entry(label_ent, &nd_mapping->labels, list)
|
|
old_num_labels++;
|
|
mutex_unlock(&nd_mapping->lock);
|
|
|
|
/*
|
|
* We need to preserve all the old labels for the mapping so
|
|
* they can be garbage collected after writing the new labels.
|
|
*/
|
|
for (i = old_num_labels; i < num_labels; i++) {
|
|
label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
|
|
if (!label_ent)
|
|
return -ENOMEM;
|
|
mutex_lock(&nd_mapping->lock);
|
|
list_add_tail(&label_ent->list, &nd_mapping->labels);
|
|
mutex_unlock(&nd_mapping->lock);
|
|
}
|
|
|
|
if (ndd->ns_current == -1 || ndd->ns_next == -1)
|
|
/* pass */;
|
|
else
|
|
return max(num_labels, old_num_labels);
|
|
|
|
nsindex = to_namespace_index(ndd, 0);
|
|
memset(nsindex, 0, ndd->nsarea.config_size);
|
|
for (i = 0; i < 2; i++) {
|
|
int rc = nd_label_write_index(ndd, i, 3 - i, ND_NSINDEX_INIT);
|
|
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
ndd->ns_next = 1;
|
|
ndd->ns_current = 0;
|
|
|
|
return max(num_labels, old_num_labels);
|
|
}
|
|
|
|
static int del_labels(struct nd_mapping *nd_mapping, u8 *uuid)
|
|
{
|
|
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
|
|
struct nd_label_ent *label_ent, *e;
|
|
struct nd_namespace_index *nsindex;
|
|
u8 label_uuid[NSLABEL_UUID_LEN];
|
|
unsigned long *free;
|
|
LIST_HEAD(list);
|
|
u32 nslot, slot;
|
|
int active = 0;
|
|
|
|
if (!uuid)
|
|
return 0;
|
|
|
|
/* no index || no labels == nothing to delete */
|
|
if (!preamble_next(ndd, &nsindex, &free, &nslot))
|
|
return 0;
|
|
|
|
mutex_lock(&nd_mapping->lock);
|
|
list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
|
|
struct nd_namespace_label *nd_label = label_ent->label;
|
|
|
|
if (!nd_label)
|
|
continue;
|
|
active++;
|
|
memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
|
|
if (memcmp(label_uuid, uuid, NSLABEL_UUID_LEN) != 0)
|
|
continue;
|
|
active--;
|
|
slot = to_slot(ndd, nd_label);
|
|
nd_label_free_slot(ndd, slot);
|
|
dev_dbg(ndd->dev, "%s: free: %d\n", __func__, slot);
|
|
list_move_tail(&label_ent->list, &list);
|
|
label_ent->label = NULL;
|
|
}
|
|
list_splice_tail_init(&list, &nd_mapping->labels);
|
|
|
|
if (active == 0) {
|
|
nd_mapping_free_labels(nd_mapping);
|
|
dev_dbg(ndd->dev, "%s: no more active labels\n", __func__);
|
|
}
|
|
mutex_unlock(&nd_mapping->lock);
|
|
|
|
return nd_label_write_index(ndd, ndd->ns_next,
|
|
nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
|
|
}
|
|
|
|
int nd_pmem_namespace_label_update(struct nd_region *nd_region,
|
|
struct nd_namespace_pmem *nspm, resource_size_t size)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nd_region->ndr_mappings; i++) {
|
|
struct nd_mapping *nd_mapping = &nd_region->mapping[i];
|
|
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
|
|
struct resource *res;
|
|
int rc, count = 0;
|
|
|
|
if (size == 0) {
|
|
rc = del_labels(nd_mapping, nspm->uuid);
|
|
if (rc)
|
|
return rc;
|
|
continue;
|
|
}
|
|
|
|
for_each_dpa_resource(ndd, res)
|
|
if (strncmp(res->name, "pmem", 4) == 0)
|
|
count++;
|
|
WARN_ON_ONCE(!count);
|
|
|
|
rc = init_labels(nd_mapping, count);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
rc = __pmem_label_update(nd_region, nd_mapping, nspm, i);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int nd_blk_namespace_label_update(struct nd_region *nd_region,
|
|
struct nd_namespace_blk *nsblk, resource_size_t size)
|
|
{
|
|
struct nd_mapping *nd_mapping = &nd_region->mapping[0];
|
|
struct resource *res;
|
|
int count = 0;
|
|
|
|
if (size == 0)
|
|
return del_labels(nd_mapping, nsblk->uuid);
|
|
|
|
for_each_dpa_resource(to_ndd(nd_mapping), res)
|
|
count++;
|
|
|
|
count = init_labels(nd_mapping, count);
|
|
if (count < 0)
|
|
return count;
|
|
|
|
return __blk_label_update(nd_region, nd_mapping, nsblk, count);
|
|
}
|
|
|
|
int __init nd_label_init(void)
|
|
{
|
|
WARN_ON(guid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_guid));
|
|
WARN_ON(guid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_guid));
|
|
WARN_ON(guid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_guid));
|
|
WARN_ON(guid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_guid));
|
|
|
|
return 0;
|
|
}
|