v4.19.13 snapshot.
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
new file mode 100644
index 0000000..3d0e2c1
--- /dev/null
+++ b/drivers/md/dm-table.c
@@ -0,0 +1,2104 @@
+/*
+ * Copyright (C) 2001 Sistina Software (UK) Limited.
+ * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
+ *
+ * This file is released under the GPL.
+ */
+
+#include "dm-core.h"
+
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/blkdev.h>
+#include <linux/namei.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/atomic.h>
+#include <linux/blk-mq.h>
+#include <linux/mount.h>
+#include <linux/dax.h>
+
+#define DM_MSG_PREFIX "table"
+
+#define MAX_DEPTH 16
+#define NODE_SIZE L1_CACHE_BYTES
+#define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
+#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
+
+struct dm_table {
+ struct mapped_device *md;
+ enum dm_queue_mode type;
+
+ /* btree table */
+ unsigned int depth;
+ unsigned int counts[MAX_DEPTH]; /* in nodes */
+ sector_t *index[MAX_DEPTH];
+
+ unsigned int num_targets;
+ unsigned int num_allocated;
+ sector_t *highs;
+ struct dm_target *targets;
+
+ struct target_type *immutable_target_type;
+
+ bool integrity_supported:1;
+ bool singleton:1;
+ bool all_blk_mq:1;
+ unsigned integrity_added:1;
+
+ /*
+ * Indicates the rw permissions for the new logical
+ * device. This should be a combination of FMODE_READ
+ * and FMODE_WRITE.
+ */
+ fmode_t mode;
+
+ /* a list of devices used by this table */
+ struct list_head devices;
+
+ /* events get handed up using this callback */
+ void (*event_fn)(void *);
+ void *event_context;
+
+ struct dm_md_mempools *mempools;
+
+ struct list_head target_callbacks;
+};
+
+/*
+ * Similar to ceiling(log_size(n))
+ */
+static unsigned int int_log(unsigned int n, unsigned int base)
+{
+ int result = 0;
+
+ while (n > 1) {
+ n = dm_div_up(n, base);
+ result++;
+ }
+
+ return result;
+}
+
+/*
+ * Calculate the index of the child node of the n'th node k'th key.
+ */
+static inline unsigned int get_child(unsigned int n, unsigned int k)
+{
+ return (n * CHILDREN_PER_NODE) + k;
+}
+
+/*
+ * Return the n'th node of level l from table t.
+ */
+static inline sector_t *get_node(struct dm_table *t,
+ unsigned int l, unsigned int n)
+{
+ return t->index[l] + (n * KEYS_PER_NODE);
+}
+
+/*
+ * Return the highest key that you could lookup from the n'th
+ * node on level l of the btree.
+ */
+static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
+{
+ for (; l < t->depth - 1; l++)
+ n = get_child(n, CHILDREN_PER_NODE - 1);
+
+ if (n >= t->counts[l])
+ return (sector_t) - 1;
+
+ return get_node(t, l, n)[KEYS_PER_NODE - 1];
+}
+
+/*
+ * Fills in a level of the btree based on the highs of the level
+ * below it.
+ */
+static int setup_btree_index(unsigned int l, struct dm_table *t)
+{
+ unsigned int n, k;
+ sector_t *node;
+
+ for (n = 0U; n < t->counts[l]; n++) {
+ node = get_node(t, l, n);
+
+ for (k = 0U; k < KEYS_PER_NODE; k++)
+ node[k] = high(t, l + 1, get_child(n, k));
+ }
+
+ return 0;
+}
+
+void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size)
+{
+ unsigned long size;
+ void *addr;
+
+ /*
+ * Check that we're not going to overflow.
+ */
+ if (nmemb > (ULONG_MAX / elem_size))
+ return NULL;
+
+ size = nmemb * elem_size;
+ addr = vzalloc(size);
+
+ return addr;
+}
+EXPORT_SYMBOL(dm_vcalloc);
+
+/*
+ * highs, and targets are managed as dynamic arrays during a
+ * table load.
+ */
+static int alloc_targets(struct dm_table *t, unsigned int num)
+{
+ sector_t *n_highs;
+ struct dm_target *n_targets;
+
+ /*
+ * Allocate both the target array and offset array at once.
+ * Append an empty entry to catch sectors beyond the end of
+ * the device.
+ */
+ n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) +
+ sizeof(sector_t));
+ if (!n_highs)
+ return -ENOMEM;
+
+ n_targets = (struct dm_target *) (n_highs + num);
+
+ memset(n_highs, -1, sizeof(*n_highs) * num);
+ vfree(t->highs);
+
+ t->num_allocated = num;
+ t->highs = n_highs;
+ t->targets = n_targets;
+
+ return 0;
+}
+
+int dm_table_create(struct dm_table **result, fmode_t mode,
+ unsigned num_targets, struct mapped_device *md)
+{
+ struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
+
+ if (!t)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&t->devices);
+ INIT_LIST_HEAD(&t->target_callbacks);
+
+ if (!num_targets)
+ num_targets = KEYS_PER_NODE;
+
+ num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
+
+ if (!num_targets) {
+ kfree(t);
+ return -ENOMEM;
+ }
+
+ if (alloc_targets(t, num_targets)) {
+ kfree(t);
+ return -ENOMEM;
+ }
+
+ t->type = DM_TYPE_NONE;
+ t->mode = mode;
+ t->md = md;
+ *result = t;
+ return 0;
+}
+
+static void free_devices(struct list_head *devices, struct mapped_device *md)
+{
+ struct list_head *tmp, *next;
+
+ list_for_each_safe(tmp, next, devices) {
+ struct dm_dev_internal *dd =
+ list_entry(tmp, struct dm_dev_internal, list);
+ DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s",
+ dm_device_name(md), dd->dm_dev->name);
+ dm_put_table_device(md, dd->dm_dev);
+ kfree(dd);
+ }
+}
+
+void dm_table_destroy(struct dm_table *t)
+{
+ unsigned int i;
+
+ if (!t)
+ return;
+
+ /* free the indexes */
+ if (t->depth >= 2)
+ vfree(t->index[t->depth - 2]);
+
+ /* free the targets */
+ for (i = 0; i < t->num_targets; i++) {
+ struct dm_target *tgt = t->targets + i;
+
+ if (tgt->type->dtr)
+ tgt->type->dtr(tgt);
+
+ dm_put_target_type(tgt->type);
+ }
+
+ vfree(t->highs);
+
+ /* free the device list */
+ free_devices(&t->devices, t->md);
+
+ dm_free_md_mempools(t->mempools);
+
+ kfree(t);
+}
+
+/*
+ * See if we've already got a device in the list.
+ */
+static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
+{
+ struct dm_dev_internal *dd;
+
+ list_for_each_entry (dd, l, list)
+ if (dd->dm_dev->bdev->bd_dev == dev)
+ return dd;
+
+ return NULL;
+}
+
+/*
+ * If possible, this checks an area of a destination device is invalid.
+ */
+static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q;
+ struct queue_limits *limits = data;
+ struct block_device *bdev = dev->bdev;
+ sector_t dev_size =
+ i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
+ unsigned short logical_block_size_sectors =
+ limits->logical_block_size >> SECTOR_SHIFT;
+ char b[BDEVNAME_SIZE];
+
+ /*
+ * Some devices exist without request functions,
+ * such as loop devices not yet bound to backing files.
+ * Forbid the use of such devices.
+ */
+ q = bdev_get_queue(bdev);
+ if (!q || !q->make_request_fn) {
+ DMWARN("%s: %s is not yet initialised: "
+ "start=%llu, len=%llu, dev_size=%llu",
+ dm_device_name(ti->table->md), bdevname(bdev, b),
+ (unsigned long long)start,
+ (unsigned long long)len,
+ (unsigned long long)dev_size);
+ return 1;
+ }
+
+ if (!dev_size)
+ return 0;
+
+ if ((start >= dev_size) || (start + len > dev_size)) {
+ DMWARN("%s: %s too small for target: "
+ "start=%llu, len=%llu, dev_size=%llu",
+ dm_device_name(ti->table->md), bdevname(bdev, b),
+ (unsigned long long)start,
+ (unsigned long long)len,
+ (unsigned long long)dev_size);
+ return 1;
+ }
+
+ /*
+ * If the target is mapped to zoned block device(s), check
+ * that the zones are not partially mapped.
+ */
+ if (bdev_zoned_model(bdev) != BLK_ZONED_NONE) {
+ unsigned int zone_sectors = bdev_zone_sectors(bdev);
+
+ if (start & (zone_sectors - 1)) {
+ DMWARN("%s: start=%llu not aligned to h/w zone size %u of %s",
+ dm_device_name(ti->table->md),
+ (unsigned long long)start,
+ zone_sectors, bdevname(bdev, b));
+ return 1;
+ }
+
+ /*
+ * Note: The last zone of a zoned block device may be smaller
+ * than other zones. So for a target mapping the end of a
+ * zoned block device with such a zone, len would not be zone
+ * aligned. We do not allow such last smaller zone to be part
+ * of the mapping here to ensure that mappings with multiple
+ * devices do not end up with a smaller zone in the middle of
+ * the sector range.
+ */
+ if (len & (zone_sectors - 1)) {
+ DMWARN("%s: len=%llu not aligned to h/w zone size %u of %s",
+ dm_device_name(ti->table->md),
+ (unsigned long long)len,
+ zone_sectors, bdevname(bdev, b));
+ return 1;
+ }
+ }
+
+ if (logical_block_size_sectors <= 1)
+ return 0;
+
+ if (start & (logical_block_size_sectors - 1)) {
+ DMWARN("%s: start=%llu not aligned to h/w "
+ "logical block size %u of %s",
+ dm_device_name(ti->table->md),
+ (unsigned long long)start,
+ limits->logical_block_size, bdevname(bdev, b));
+ return 1;
+ }
+
+ if (len & (logical_block_size_sectors - 1)) {
+ DMWARN("%s: len=%llu not aligned to h/w "
+ "logical block size %u of %s",
+ dm_device_name(ti->table->md),
+ (unsigned long long)len,
+ limits->logical_block_size, bdevname(bdev, b));
+ return 1;
+ }
+
+ return 0;
+}
+
+/*
+ * This upgrades the mode on an already open dm_dev, being
+ * careful to leave things as they were if we fail to reopen the
+ * device and not to touch the existing bdev field in case
+ * it is accessed concurrently inside dm_table_any_congested().
+ */
+static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
+ struct mapped_device *md)
+{
+ int r;
+ struct dm_dev *old_dev, *new_dev;
+
+ old_dev = dd->dm_dev;
+
+ r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev,
+ dd->dm_dev->mode | new_mode, &new_dev);
+ if (r)
+ return r;
+
+ dd->dm_dev = new_dev;
+ dm_put_table_device(md, old_dev);
+
+ return 0;
+}
+
+/*
+ * Convert the path to a device
+ */
+dev_t dm_get_dev_t(const char *path)
+{
+ dev_t dev;
+ struct block_device *bdev;
+
+ bdev = lookup_bdev(path);
+ if (IS_ERR(bdev))
+ dev = name_to_dev_t(path);
+ else {
+ dev = bdev->bd_dev;
+ bdput(bdev);
+ }
+
+ return dev;
+}
+EXPORT_SYMBOL_GPL(dm_get_dev_t);
+
+/*
+ * Add a device to the list, or just increment the usage count if
+ * it's already present.
+ */
+int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
+ struct dm_dev **result)
+{
+ int r;
+ dev_t dev;
+ struct dm_dev_internal *dd;
+ struct dm_table *t = ti->table;
+
+ BUG_ON(!t);
+
+ dev = dm_get_dev_t(path);
+ if (!dev)
+ return -ENODEV;
+
+ dd = find_device(&t->devices, dev);
+ if (!dd) {
+ dd = kmalloc(sizeof(*dd), GFP_KERNEL);
+ if (!dd)
+ return -ENOMEM;
+
+ if ((r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev))) {
+ kfree(dd);
+ return r;
+ }
+
+ refcount_set(&dd->count, 1);
+ list_add(&dd->list, &t->devices);
+ goto out;
+
+ } else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) {
+ r = upgrade_mode(dd, mode, t->md);
+ if (r)
+ return r;
+ }
+ refcount_inc(&dd->count);
+out:
+ *result = dd->dm_dev;
+ return 0;
+}
+EXPORT_SYMBOL(dm_get_device);
+
+static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct queue_limits *limits = data;
+ struct block_device *bdev = dev->bdev;
+ struct request_queue *q = bdev_get_queue(bdev);
+ char b[BDEVNAME_SIZE];
+
+ if (unlikely(!q)) {
+ DMWARN("%s: Cannot set limits for nonexistent device %s",
+ dm_device_name(ti->table->md), bdevname(bdev, b));
+ return 0;
+ }
+
+ if (bdev_stack_limits(limits, bdev, start) < 0)
+ DMWARN("%s: adding target device %s caused an alignment inconsistency: "
+ "physical_block_size=%u, logical_block_size=%u, "
+ "alignment_offset=%u, start=%llu",
+ dm_device_name(ti->table->md), bdevname(bdev, b),
+ q->limits.physical_block_size,
+ q->limits.logical_block_size,
+ q->limits.alignment_offset,
+ (unsigned long long) start << SECTOR_SHIFT);
+
+ limits->zoned = blk_queue_zoned_model(q);
+
+ return 0;
+}
+
+/*
+ * Decrement a device's use count and remove it if necessary.
+ */
+void dm_put_device(struct dm_target *ti, struct dm_dev *d)
+{
+ int found = 0;
+ struct list_head *devices = &ti->table->devices;
+ struct dm_dev_internal *dd;
+
+ list_for_each_entry(dd, devices, list) {
+ if (dd->dm_dev == d) {
+ found = 1;
+ break;
+ }
+ }
+ if (!found) {
+ DMWARN("%s: device %s not in table devices list",
+ dm_device_name(ti->table->md), d->name);
+ return;
+ }
+ if (refcount_dec_and_test(&dd->count)) {
+ dm_put_table_device(ti->table->md, d);
+ list_del(&dd->list);
+ kfree(dd);
+ }
+}
+EXPORT_SYMBOL(dm_put_device);
+
+/*
+ * Checks to see if the target joins onto the end of the table.
+ */
+static int adjoin(struct dm_table *table, struct dm_target *ti)
+{
+ struct dm_target *prev;
+
+ if (!table->num_targets)
+ return !ti->begin;
+
+ prev = &table->targets[table->num_targets - 1];
+ return (ti->begin == (prev->begin + prev->len));
+}
+
+/*
+ * Used to dynamically allocate the arg array.
+ *
+ * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must
+ * process messages even if some device is suspended. These messages have a
+ * small fixed number of arguments.
+ *
+ * On the other hand, dm-switch needs to process bulk data using messages and
+ * excessive use of GFP_NOIO could cause trouble.
+ */
+static char **realloc_argv(unsigned *size, char **old_argv)
+{
+ char **argv;
+ unsigned new_size;
+ gfp_t gfp;
+
+ if (*size) {
+ new_size = *size * 2;
+ gfp = GFP_KERNEL;
+ } else {
+ new_size = 8;
+ gfp = GFP_NOIO;
+ }
+ argv = kmalloc_array(new_size, sizeof(*argv), gfp);
+ if (argv) {
+ memcpy(argv, old_argv, *size * sizeof(*argv));
+ *size = new_size;
+ }
+
+ kfree(old_argv);
+ return argv;
+}
+
+/*
+ * Destructively splits up the argument list to pass to ctr.
+ */
+int dm_split_args(int *argc, char ***argvp, char *input)
+{
+ char *start, *end = input, *out, **argv = NULL;
+ unsigned array_size = 0;
+
+ *argc = 0;
+
+ if (!input) {
+ *argvp = NULL;
+ return 0;
+ }
+
+ argv = realloc_argv(&array_size, argv);
+ if (!argv)
+ return -ENOMEM;
+
+ while (1) {
+ /* Skip whitespace */
+ start = skip_spaces(end);
+
+ if (!*start)
+ break; /* success, we hit the end */
+
+ /* 'out' is used to remove any back-quotes */
+ end = out = start;
+ while (*end) {
+ /* Everything apart from '\0' can be quoted */
+ if (*end == '\\' && *(end + 1)) {
+ *out++ = *(end + 1);
+ end += 2;
+ continue;
+ }
+
+ if (isspace(*end))
+ break; /* end of token */
+
+ *out++ = *end++;
+ }
+
+ /* have we already filled the array ? */
+ if ((*argc + 1) > array_size) {
+ argv = realloc_argv(&array_size, argv);
+ if (!argv)
+ return -ENOMEM;
+ }
+
+ /* we know this is whitespace */
+ if (*end)
+ end++;
+
+ /* terminate the string and put it in the array */
+ *out = '\0';
+ argv[*argc] = start;
+ (*argc)++;
+ }
+
+ *argvp = argv;
+ return 0;
+}
+
+/*
+ * Impose necessary and sufficient conditions on a devices's table such
+ * that any incoming bio which respects its logical_block_size can be
+ * processed successfully. If it falls across the boundary between
+ * two or more targets, the size of each piece it gets split into must
+ * be compatible with the logical_block_size of the target processing it.
+ */
+static int validate_hardware_logical_block_alignment(struct dm_table *table,
+ struct queue_limits *limits)
+{
+ /*
+ * This function uses arithmetic modulo the logical_block_size
+ * (in units of 512-byte sectors).
+ */
+ unsigned short device_logical_block_size_sects =
+ limits->logical_block_size >> SECTOR_SHIFT;
+
+ /*
+ * Offset of the start of the next table entry, mod logical_block_size.
+ */
+ unsigned short next_target_start = 0;
+
+ /*
+ * Given an aligned bio that extends beyond the end of a
+ * target, how many sectors must the next target handle?
+ */
+ unsigned short remaining = 0;
+
+ struct dm_target *uninitialized_var(ti);
+ struct queue_limits ti_limits;
+ unsigned i;
+
+ /*
+ * Check each entry in the table in turn.
+ */
+ for (i = 0; i < dm_table_get_num_targets(table); i++) {
+ ti = dm_table_get_target(table, i);
+
+ blk_set_stacking_limits(&ti_limits);
+
+ /* combine all target devices' limits */
+ if (ti->type->iterate_devices)
+ ti->type->iterate_devices(ti, dm_set_device_limits,
+ &ti_limits);
+
+ /*
+ * If the remaining sectors fall entirely within this
+ * table entry are they compatible with its logical_block_size?
+ */
+ if (remaining < ti->len &&
+ remaining & ((ti_limits.logical_block_size >>
+ SECTOR_SHIFT) - 1))
+ break; /* Error */
+
+ next_target_start =
+ (unsigned short) ((next_target_start + ti->len) &
+ (device_logical_block_size_sects - 1));
+ remaining = next_target_start ?
+ device_logical_block_size_sects - next_target_start : 0;
+ }
+
+ if (remaining) {
+ DMWARN("%s: table line %u (start sect %llu len %llu) "
+ "not aligned to h/w logical block size %u",
+ dm_device_name(table->md), i,
+ (unsigned long long) ti->begin,
+ (unsigned long long) ti->len,
+ limits->logical_block_size);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+int dm_table_add_target(struct dm_table *t, const char *type,
+ sector_t start, sector_t len, char *params)
+{
+ int r = -EINVAL, argc;
+ char **argv;
+ struct dm_target *tgt;
+
+ if (t->singleton) {
+ DMERR("%s: target type %s must appear alone in table",
+ dm_device_name(t->md), t->targets->type->name);
+ return -EINVAL;
+ }
+
+ BUG_ON(t->num_targets >= t->num_allocated);
+
+ tgt = t->targets + t->num_targets;
+ memset(tgt, 0, sizeof(*tgt));
+
+ if (!len) {
+ DMERR("%s: zero-length target", dm_device_name(t->md));
+ return -EINVAL;
+ }
+
+ tgt->type = dm_get_target_type(type);
+ if (!tgt->type) {
+ DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
+ return -EINVAL;
+ }
+
+ if (dm_target_needs_singleton(tgt->type)) {
+ if (t->num_targets) {
+ tgt->error = "singleton target type must appear alone in table";
+ goto bad;
+ }
+ t->singleton = true;
+ }
+
+ if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) {
+ tgt->error = "target type may not be included in a read-only table";
+ goto bad;
+ }
+
+ if (t->immutable_target_type) {
+ if (t->immutable_target_type != tgt->type) {
+ tgt->error = "immutable target type cannot be mixed with other target types";
+ goto bad;
+ }
+ } else if (dm_target_is_immutable(tgt->type)) {
+ if (t->num_targets) {
+ tgt->error = "immutable target type cannot be mixed with other target types";
+ goto bad;
+ }
+ t->immutable_target_type = tgt->type;
+ }
+
+ if (dm_target_has_integrity(tgt->type))
+ t->integrity_added = 1;
+
+ tgt->table = t;
+ tgt->begin = start;
+ tgt->len = len;
+ tgt->error = "Unknown error";
+
+ /*
+ * Does this target adjoin the previous one ?
+ */
+ if (!adjoin(t, tgt)) {
+ tgt->error = "Gap in table";
+ goto bad;
+ }
+
+ r = dm_split_args(&argc, &argv, params);
+ if (r) {
+ tgt->error = "couldn't split parameters (insufficient memory)";
+ goto bad;
+ }
+
+ r = tgt->type->ctr(tgt, argc, argv);
+ kfree(argv);
+ if (r)
+ goto bad;
+
+ t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
+
+ if (!tgt->num_discard_bios && tgt->discards_supported)
+ DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.",
+ dm_device_name(t->md), type);
+
+ return 0;
+
+ bad:
+ DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error);
+ dm_put_target_type(tgt->type);
+ return r;
+}
+
+/*
+ * Target argument parsing helpers.
+ */
+static int validate_next_arg(const struct dm_arg *arg,
+ struct dm_arg_set *arg_set,
+ unsigned *value, char **error, unsigned grouped)
+{
+ const char *arg_str = dm_shift_arg(arg_set);
+ char dummy;
+
+ if (!arg_str ||
+ (sscanf(arg_str, "%u%c", value, &dummy) != 1) ||
+ (*value < arg->min) ||
+ (*value > arg->max) ||
+ (grouped && arg_set->argc < *value)) {
+ *error = arg->error;
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set,
+ unsigned *value, char **error)
+{
+ return validate_next_arg(arg, arg_set, value, error, 0);
+}
+EXPORT_SYMBOL(dm_read_arg);
+
+int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set,
+ unsigned *value, char **error)
+{
+ return validate_next_arg(arg, arg_set, value, error, 1);
+}
+EXPORT_SYMBOL(dm_read_arg_group);
+
+const char *dm_shift_arg(struct dm_arg_set *as)
+{
+ char *r;
+
+ if (as->argc) {
+ as->argc--;
+ r = *as->argv;
+ as->argv++;
+ return r;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL(dm_shift_arg);
+
+void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
+{
+ BUG_ON(as->argc < num_args);
+ as->argc -= num_args;
+ as->argv += num_args;
+}
+EXPORT_SYMBOL(dm_consume_args);
+
+static bool __table_type_bio_based(enum dm_queue_mode table_type)
+{
+ return (table_type == DM_TYPE_BIO_BASED ||
+ table_type == DM_TYPE_DAX_BIO_BASED ||
+ table_type == DM_TYPE_NVME_BIO_BASED);
+}
+
+static bool __table_type_request_based(enum dm_queue_mode table_type)
+{
+ return (table_type == DM_TYPE_REQUEST_BASED ||
+ table_type == DM_TYPE_MQ_REQUEST_BASED);
+}
+
+void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type)
+{
+ t->type = type;
+}
+EXPORT_SYMBOL_GPL(dm_table_set_type);
+
+static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ return bdev_dax_supported(dev->bdev, PAGE_SIZE);
+}
+
+static bool dm_table_supports_dax(struct dm_table *t)
+{
+ struct dm_target *ti;
+ unsigned i;
+
+ /* Ensure that all targets support DAX. */
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+
+ if (!ti->type->direct_access)
+ return false;
+
+ if (!ti->type->iterate_devices ||
+ !ti->type->iterate_devices(ti, device_supports_dax, NULL))
+ return false;
+ }
+
+ return true;
+}
+
+static bool dm_table_does_not_support_partial_completion(struct dm_table *t);
+
+struct verify_rq_based_data {
+ unsigned sq_count;
+ unsigned mq_count;
+};
+
+static int device_is_rq_based(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+ struct verify_rq_based_data *v = data;
+
+ if (q->mq_ops)
+ v->mq_count++;
+ else
+ v->sq_count++;
+
+ return queue_is_rq_based(q);
+}
+
+static int dm_table_determine_type(struct dm_table *t)
+{
+ unsigned i;
+ unsigned bio_based = 0, request_based = 0, hybrid = 0;
+ struct verify_rq_based_data v = {.sq_count = 0, .mq_count = 0};
+ struct dm_target *tgt;
+ struct list_head *devices = dm_table_get_devices(t);
+ enum dm_queue_mode live_md_type = dm_get_md_type(t->md);
+
+ if (t->type != DM_TYPE_NONE) {
+ /* target already set the table's type */
+ if (t->type == DM_TYPE_BIO_BASED) {
+ /* possibly upgrade to a variant of bio-based */
+ goto verify_bio_based;
+ }
+ BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
+ BUG_ON(t->type == DM_TYPE_NVME_BIO_BASED);
+ goto verify_rq_based;
+ }
+
+ for (i = 0; i < t->num_targets; i++) {
+ tgt = t->targets + i;
+ if (dm_target_hybrid(tgt))
+ hybrid = 1;
+ else if (dm_target_request_based(tgt))
+ request_based = 1;
+ else
+ bio_based = 1;
+
+ if (bio_based && request_based) {
+ DMERR("Inconsistent table: different target types"
+ " can't be mixed up");
+ return -EINVAL;
+ }
+ }
+
+ if (hybrid && !bio_based && !request_based) {
+ /*
+ * The targets can work either way.
+ * Determine the type from the live device.
+ * Default to bio-based if device is new.
+ */
+ if (__table_type_request_based(live_md_type))
+ request_based = 1;
+ else
+ bio_based = 1;
+ }
+
+ if (bio_based) {
+verify_bio_based:
+ /* We must use this table as bio-based */
+ t->type = DM_TYPE_BIO_BASED;
+ if (dm_table_supports_dax(t) ||
+ (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) {
+ t->type = DM_TYPE_DAX_BIO_BASED;
+ } else {
+ /* Check if upgrading to NVMe bio-based is valid or required */
+ tgt = dm_table_get_immutable_target(t);
+ if (tgt && !tgt->max_io_len && dm_table_does_not_support_partial_completion(t)) {
+ t->type = DM_TYPE_NVME_BIO_BASED;
+ goto verify_rq_based; /* must be stacked directly on NVMe (blk-mq) */
+ } else if (list_empty(devices) && live_md_type == DM_TYPE_NVME_BIO_BASED) {
+ t->type = DM_TYPE_NVME_BIO_BASED;
+ }
+ }
+ return 0;
+ }
+
+ BUG_ON(!request_based); /* No targets in this table */
+
+ /*
+ * The only way to establish DM_TYPE_MQ_REQUEST_BASED is by
+ * having a compatible target use dm_table_set_type.
+ */
+ t->type = DM_TYPE_REQUEST_BASED;
+
+verify_rq_based:
+ /*
+ * Request-based dm supports only tables that have a single target now.
+ * To support multiple targets, request splitting support is needed,
+ * and that needs lots of changes in the block-layer.
+ * (e.g. request completion process for partial completion.)
+ */
+ if (t->num_targets > 1) {
+ DMERR("%s DM doesn't support multiple targets",
+ t->type == DM_TYPE_NVME_BIO_BASED ? "nvme bio-based" : "request-based");
+ return -EINVAL;
+ }
+
+ if (list_empty(devices)) {
+ int srcu_idx;
+ struct dm_table *live_table = dm_get_live_table(t->md, &srcu_idx);
+
+ /* inherit live table's type and all_blk_mq */
+ if (live_table) {
+ t->type = live_table->type;
+ t->all_blk_mq = live_table->all_blk_mq;
+ }
+ dm_put_live_table(t->md, srcu_idx);
+ return 0;
+ }
+
+ tgt = dm_table_get_immutable_target(t);
+ if (!tgt) {
+ DMERR("table load rejected: immutable target is required");
+ return -EINVAL;
+ } else if (tgt->max_io_len) {
+ DMERR("table load rejected: immutable target that splits IO is not supported");
+ return -EINVAL;
+ }
+
+ /* Non-request-stackable devices can't be used for request-based dm */
+ if (!tgt->type->iterate_devices ||
+ !tgt->type->iterate_devices(tgt, device_is_rq_based, &v)) {
+ DMERR("table load rejected: including non-request-stackable devices");
+ return -EINVAL;
+ }
+ if (v.sq_count && v.mq_count) {
+ DMERR("table load rejected: not all devices are blk-mq request-stackable");
+ return -EINVAL;
+ }
+ t->all_blk_mq = v.mq_count > 0;
+
+ if (!t->all_blk_mq &&
+ (t->type == DM_TYPE_MQ_REQUEST_BASED || t->type == DM_TYPE_NVME_BIO_BASED)) {
+ DMERR("table load rejected: all devices are not blk-mq request-stackable");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+enum dm_queue_mode dm_table_get_type(struct dm_table *t)
+{
+ return t->type;
+}
+
+struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
+{
+ return t->immutable_target_type;
+}
+
+struct dm_target *dm_table_get_immutable_target(struct dm_table *t)
+{
+ /* Immutable target is implicitly a singleton */
+ if (t->num_targets > 1 ||
+ !dm_target_is_immutable(t->targets[0].type))
+ return NULL;
+
+ return t->targets;
+}
+
+struct dm_target *dm_table_get_wildcard_target(struct dm_table *t)
+{
+ struct dm_target *ti;
+ unsigned i;
+
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+ if (dm_target_is_wildcard(ti->type))
+ return ti;
+ }
+
+ return NULL;
+}
+
+bool dm_table_bio_based(struct dm_table *t)
+{
+ return __table_type_bio_based(dm_table_get_type(t));
+}
+
+bool dm_table_request_based(struct dm_table *t)
+{
+ return __table_type_request_based(dm_table_get_type(t));
+}
+
+bool dm_table_all_blk_mq_devices(struct dm_table *t)
+{
+ return t->all_blk_mq;
+}
+
+static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md)
+{
+ enum dm_queue_mode type = dm_table_get_type(t);
+ unsigned per_io_data_size = 0;
+ unsigned min_pool_size = 0;
+ struct dm_target *ti;
+ unsigned i;
+
+ if (unlikely(type == DM_TYPE_NONE)) {
+ DMWARN("no table type is set, can't allocate mempools");
+ return -EINVAL;
+ }
+
+ if (__table_type_bio_based(type))
+ for (i = 0; i < t->num_targets; i++) {
+ ti = t->targets + i;
+ per_io_data_size = max(per_io_data_size, ti->per_io_data_size);
+ min_pool_size = max(min_pool_size, ti->num_flush_bios);
+ }
+
+ t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported,
+ per_io_data_size, min_pool_size);
+ if (!t->mempools)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void dm_table_free_md_mempools(struct dm_table *t)
+{
+ dm_free_md_mempools(t->mempools);
+ t->mempools = NULL;
+}
+
+struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
+{
+ return t->mempools;
+}
+
+static int setup_indexes(struct dm_table *t)
+{
+ int i;
+ unsigned int total = 0;
+ sector_t *indexes;
+
+ /* allocate the space for *all* the indexes */
+ for (i = t->depth - 2; i >= 0; i--) {
+ t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE);
+ total += t->counts[i];
+ }
+
+ indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE);
+ if (!indexes)
+ return -ENOMEM;
+
+ /* set up internal nodes, bottom-up */
+ for (i = t->depth - 2; i >= 0; i--) {
+ t->index[i] = indexes;
+ indexes += (KEYS_PER_NODE * t->counts[i]);
+ setup_btree_index(i, t);
+ }
+
+ return 0;
+}
+
+/*
+ * Builds the btree to index the map.
+ */
+static int dm_table_build_index(struct dm_table *t)
+{
+ int r = 0;
+ unsigned int leaf_nodes;
+
+ /* how many indexes will the btree have ? */
+ leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
+ t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
+
+ /* leaf layer has already been set up */
+ t->counts[t->depth - 1] = leaf_nodes;
+ t->index[t->depth - 1] = t->highs;
+
+ if (t->depth >= 2)
+ r = setup_indexes(t);
+
+ return r;
+}
+
+static bool integrity_profile_exists(struct gendisk *disk)
+{
+ return !!blk_get_integrity(disk);
+}
+
+/*
+ * Get a disk whose integrity profile reflects the table's profile.
+ * Returns NULL if integrity support was inconsistent or unavailable.
+ */
+static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t)
+{
+ struct list_head *devices = dm_table_get_devices(t);
+ struct dm_dev_internal *dd = NULL;
+ struct gendisk *prev_disk = NULL, *template_disk = NULL;
+ unsigned i;
+
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ struct dm_target *ti = dm_table_get_target(t, i);
+ if (!dm_target_passes_integrity(ti->type))
+ goto no_integrity;
+ }
+
+ list_for_each_entry(dd, devices, list) {
+ template_disk = dd->dm_dev->bdev->bd_disk;
+ if (!integrity_profile_exists(template_disk))
+ goto no_integrity;
+ else if (prev_disk &&
+ blk_integrity_compare(prev_disk, template_disk) < 0)
+ goto no_integrity;
+ prev_disk = template_disk;
+ }
+
+ return template_disk;
+
+no_integrity:
+ if (prev_disk)
+ DMWARN("%s: integrity not set: %s and %s profile mismatch",
+ dm_device_name(t->md),
+ prev_disk->disk_name,
+ template_disk->disk_name);
+ return NULL;
+}
+
+/*
+ * Register the mapped device for blk_integrity support if the
+ * underlying devices have an integrity profile. But all devices may
+ * not have matching profiles (checking all devices isn't reliable
+ * during table load because this table may use other DM device(s) which
+ * must be resumed before they will have an initialized integity
+ * profile). Consequently, stacked DM devices force a 2 stage integrity
+ * profile validation: First pass during table load, final pass during
+ * resume.
+ */
+static int dm_table_register_integrity(struct dm_table *t)
+{
+ struct mapped_device *md = t->md;
+ struct gendisk *template_disk = NULL;
+
+ /* If target handles integrity itself do not register it here. */
+ if (t->integrity_added)
+ return 0;
+
+ template_disk = dm_table_get_integrity_disk(t);
+ if (!template_disk)
+ return 0;
+
+ if (!integrity_profile_exists(dm_disk(md))) {
+ t->integrity_supported = true;
+ /*
+ * Register integrity profile during table load; we can do
+ * this because the final profile must match during resume.
+ */
+ blk_integrity_register(dm_disk(md),
+ blk_get_integrity(template_disk));
+ return 0;
+ }
+
+ /*
+ * If DM device already has an initialized integrity
+ * profile the new profile should not conflict.
+ */
+ if (blk_integrity_compare(dm_disk(md), template_disk) < 0) {
+ DMWARN("%s: conflict with existing integrity profile: "
+ "%s profile mismatch",
+ dm_device_name(t->md),
+ template_disk->disk_name);
+ return 1;
+ }
+
+ /* Preserve existing integrity profile */
+ t->integrity_supported = true;
+ return 0;
+}
+
+/*
+ * Prepares the table for use by building the indices,
+ * setting the type, and allocating mempools.
+ */
+int dm_table_complete(struct dm_table *t)
+{
+ int r;
+
+ r = dm_table_determine_type(t);
+ if (r) {
+ DMERR("unable to determine table type");
+ return r;
+ }
+
+ r = dm_table_build_index(t);
+ if (r) {
+ DMERR("unable to build btrees");
+ return r;
+ }
+
+ r = dm_table_register_integrity(t);
+ if (r) {
+ DMERR("could not register integrity profile.");
+ return r;
+ }
+
+ r = dm_table_alloc_md_mempools(t, t->md);
+ if (r)
+ DMERR("unable to allocate mempools");
+
+ return r;
+}
+
+static DEFINE_MUTEX(_event_lock);
+void dm_table_event_callback(struct dm_table *t,
+ void (*fn)(void *), void *context)
+{
+ mutex_lock(&_event_lock);
+ t->event_fn = fn;
+ t->event_context = context;
+ mutex_unlock(&_event_lock);
+}
+
+void dm_table_event(struct dm_table *t)
+{
+ /*
+ * You can no longer call dm_table_event() from interrupt
+ * context, use a bottom half instead.
+ */
+ BUG_ON(in_interrupt());
+
+ mutex_lock(&_event_lock);
+ if (t->event_fn)
+ t->event_fn(t->event_context);
+ mutex_unlock(&_event_lock);
+}
+EXPORT_SYMBOL(dm_table_event);
+
+sector_t dm_table_get_size(struct dm_table *t)
+{
+ return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
+}
+EXPORT_SYMBOL(dm_table_get_size);
+
+struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
+{
+ if (index >= t->num_targets)
+ return NULL;
+
+ return t->targets + index;
+}
+
+/*
+ * Search the btree for the correct target.
+ *
+ * Caller should check returned pointer with dm_target_is_valid()
+ * to trap I/O beyond end of device.
+ */
+struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
+{
+ unsigned int l, n = 0, k = 0;
+ sector_t *node;
+
+ for (l = 0; l < t->depth; l++) {
+ n = get_child(n, k);
+ node = get_node(t, l, n);
+
+ for (k = 0; k < KEYS_PER_NODE; k++)
+ if (node[k] >= sector)
+ break;
+ }
+
+ return &t->targets[(KEYS_PER_NODE * n) + k];
+}
+
+static int count_device(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ unsigned *num_devices = data;
+
+ (*num_devices)++;
+
+ return 0;
+}
+
+/*
+ * Check whether a table has no data devices attached using each
+ * target's iterate_devices method.
+ * Returns false if the result is unknown because a target doesn't
+ * support iterate_devices.
+ */
+bool dm_table_has_no_data_devices(struct dm_table *table)
+{
+ struct dm_target *ti;
+ unsigned i, num_devices;
+
+ for (i = 0; i < dm_table_get_num_targets(table); i++) {
+ ti = dm_table_get_target(table, i);
+
+ if (!ti->type->iterate_devices)
+ return false;
+
+ num_devices = 0;
+ ti->type->iterate_devices(ti, count_device, &num_devices);
+ if (num_devices)
+ return false;
+ }
+
+ return true;
+}
+
+static int device_is_zoned_model(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+ enum blk_zoned_model *zoned_model = data;
+
+ return q && blk_queue_zoned_model(q) == *zoned_model;
+}
+
+static bool dm_table_supports_zoned_model(struct dm_table *t,
+ enum blk_zoned_model zoned_model)
+{
+ struct dm_target *ti;
+ unsigned i;
+
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+
+ if (zoned_model == BLK_ZONED_HM &&
+ !dm_target_supports_zoned_hm(ti->type))
+ return false;
+
+ if (!ti->type->iterate_devices ||
+ !ti->type->iterate_devices(ti, device_is_zoned_model, &zoned_model))
+ return false;
+ }
+
+ return true;
+}
+
+static int device_matches_zone_sectors(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+ unsigned int *zone_sectors = data;
+
+ return q && blk_queue_zone_sectors(q) == *zone_sectors;
+}
+
+static bool dm_table_matches_zone_sectors(struct dm_table *t,
+ unsigned int zone_sectors)
+{
+ struct dm_target *ti;
+ unsigned i;
+
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+
+ if (!ti->type->iterate_devices ||
+ !ti->type->iterate_devices(ti, device_matches_zone_sectors, &zone_sectors))
+ return false;
+ }
+
+ return true;
+}
+
+static int validate_hardware_zoned_model(struct dm_table *table,
+ enum blk_zoned_model zoned_model,
+ unsigned int zone_sectors)
+{
+ if (zoned_model == BLK_ZONED_NONE)
+ return 0;
+
+ if (!dm_table_supports_zoned_model(table, zoned_model)) {
+ DMERR("%s: zoned model is not consistent across all devices",
+ dm_device_name(table->md));
+ return -EINVAL;
+ }
+
+ /* Check zone size validity and compatibility */
+ if (!zone_sectors || !is_power_of_2(zone_sectors))
+ return -EINVAL;
+
+ if (!dm_table_matches_zone_sectors(table, zone_sectors)) {
+ DMERR("%s: zone sectors is not consistent across all devices",
+ dm_device_name(table->md));
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * Establish the new table's queue_limits and validate them.
+ */
+int dm_calculate_queue_limits(struct dm_table *table,
+ struct queue_limits *limits)
+{
+ struct dm_target *ti;
+ struct queue_limits ti_limits;
+ unsigned i;
+ enum blk_zoned_model zoned_model = BLK_ZONED_NONE;
+ unsigned int zone_sectors = 0;
+
+ blk_set_stacking_limits(limits);
+
+ for (i = 0; i < dm_table_get_num_targets(table); i++) {
+ blk_set_stacking_limits(&ti_limits);
+
+ ti = dm_table_get_target(table, i);
+
+ if (!ti->type->iterate_devices)
+ goto combine_limits;
+
+ /*
+ * Combine queue limits of all the devices this target uses.
+ */
+ ti->type->iterate_devices(ti, dm_set_device_limits,
+ &ti_limits);
+
+ if (zoned_model == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) {
+ /*
+ * After stacking all limits, validate all devices
+ * in table support this zoned model and zone sectors.
+ */
+ zoned_model = ti_limits.zoned;
+ zone_sectors = ti_limits.chunk_sectors;
+ }
+
+ /* Set I/O hints portion of queue limits */
+ if (ti->type->io_hints)
+ ti->type->io_hints(ti, &ti_limits);
+
+ /*
+ * Check each device area is consistent with the target's
+ * overall queue limits.
+ */
+ if (ti->type->iterate_devices(ti, device_area_is_invalid,
+ &ti_limits))
+ return -EINVAL;
+
+combine_limits:
+ /*
+ * Merge this target's queue limits into the overall limits
+ * for the table.
+ */
+ if (blk_stack_limits(limits, &ti_limits, 0) < 0)
+ DMWARN("%s: adding target device "
+ "(start sect %llu len %llu) "
+ "caused an alignment inconsistency",
+ dm_device_name(table->md),
+ (unsigned long long) ti->begin,
+ (unsigned long long) ti->len);
+
+ /*
+ * FIXME: this should likely be moved to blk_stack_limits(), would
+ * also eliminate limits->zoned stacking hack in dm_set_device_limits()
+ */
+ if (limits->zoned == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) {
+ /*
+ * By default, the stacked limits zoned model is set to
+ * BLK_ZONED_NONE in blk_set_stacking_limits(). Update
+ * this model using the first target model reported
+ * that is not BLK_ZONED_NONE. This will be either the
+ * first target device zoned model or the model reported
+ * by the target .io_hints.
+ */
+ limits->zoned = ti_limits.zoned;
+ }
+ }
+
+ /*
+ * Verify that the zoned model and zone sectors, as determined before
+ * any .io_hints override, are the same across all devices in the table.
+ * - this is especially relevant if .io_hints is emulating a disk-managed
+ * zoned model (aka BLK_ZONED_NONE) on host-managed zoned block devices.
+ * BUT...
+ */
+ if (limits->zoned != BLK_ZONED_NONE) {
+ /*
+ * ...IF the above limits stacking determined a zoned model
+ * validate that all of the table's devices conform to it.
+ */
+ zoned_model = limits->zoned;
+ zone_sectors = limits->chunk_sectors;
+ }
+ if (validate_hardware_zoned_model(table, zoned_model, zone_sectors))
+ return -EINVAL;
+
+ return validate_hardware_logical_block_alignment(table, limits);
+}
+
+/*
+ * Verify that all devices have an integrity profile that matches the
+ * DM device's registered integrity profile. If the profiles don't
+ * match then unregister the DM device's integrity profile.
+ */
+static void dm_table_verify_integrity(struct dm_table *t)
+{
+ struct gendisk *template_disk = NULL;
+
+ if (t->integrity_added)
+ return;
+
+ if (t->integrity_supported) {
+ /*
+ * Verify that the original integrity profile
+ * matches all the devices in this table.
+ */
+ template_disk = dm_table_get_integrity_disk(t);
+ if (template_disk &&
+ blk_integrity_compare(dm_disk(t->md), template_disk) >= 0)
+ return;
+ }
+
+ if (integrity_profile_exists(dm_disk(t->md))) {
+ DMWARN("%s: unable to establish an integrity profile",
+ dm_device_name(t->md));
+ blk_integrity_unregister(dm_disk(t->md));
+ }
+}
+
+static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ unsigned long flush = (unsigned long) data;
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && (q->queue_flags & flush);
+}
+
+static bool dm_table_supports_flush(struct dm_table *t, unsigned long flush)
+{
+ struct dm_target *ti;
+ unsigned i;
+
+ /*
+ * Require at least one underlying device to support flushes.
+ * t->devices includes internal dm devices such as mirror logs
+ * so we need to use iterate_devices here, which targets
+ * supporting flushes must provide.
+ */
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+
+ if (!ti->num_flush_bios)
+ continue;
+
+ if (ti->flush_supported)
+ return true;
+
+ if (ti->type->iterate_devices &&
+ ti->type->iterate_devices(ti, device_flush_capable, (void *) flush))
+ return true;
+ }
+
+ return false;
+}
+
+static int device_dax_write_cache_enabled(struct dm_target *ti,
+ struct dm_dev *dev, sector_t start,
+ sector_t len, void *data)
+{
+ struct dax_device *dax_dev = dev->dax_dev;
+
+ if (!dax_dev)
+ return false;
+
+ if (dax_write_cache_enabled(dax_dev))
+ return true;
+ return false;
+}
+
+static int dm_table_supports_dax_write_cache(struct dm_table *t)
+{
+ struct dm_target *ti;
+ unsigned i;
+
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+
+ if (ti->type->iterate_devices &&
+ ti->type->iterate_devices(ti,
+ device_dax_write_cache_enabled, NULL))
+ return true;
+ }
+
+ return false;
+}
+
+static int device_is_nonrot(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && blk_queue_nonrot(q);
+}
+
+static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && !blk_queue_add_random(q);
+}
+
+static int queue_supports_sg_merge(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && !test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags);
+}
+
+static bool dm_table_all_devices_attribute(struct dm_table *t,
+ iterate_devices_callout_fn func)
+{
+ struct dm_target *ti;
+ unsigned i;
+
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+
+ if (!ti->type->iterate_devices ||
+ !ti->type->iterate_devices(ti, func, NULL))
+ return false;
+ }
+
+ return true;
+}
+
+static int device_no_partial_completion(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ char b[BDEVNAME_SIZE];
+
+ /* For now, NVMe devices are the only devices of this class */
+ return (strncmp(bdevname(dev->bdev, b), "nvme", 4) == 0);
+}
+
+static bool dm_table_does_not_support_partial_completion(struct dm_table *t)
+{
+ return dm_table_all_devices_attribute(t, device_no_partial_completion);
+}
+
+static int device_not_write_same_capable(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && !q->limits.max_write_same_sectors;
+}
+
+static bool dm_table_supports_write_same(struct dm_table *t)
+{
+ struct dm_target *ti;
+ unsigned i;
+
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+
+ if (!ti->num_write_same_bios)
+ return false;
+
+ if (!ti->type->iterate_devices ||
+ ti->type->iterate_devices(ti, device_not_write_same_capable, NULL))
+ return false;
+ }
+
+ return true;
+}
+
+static int device_not_write_zeroes_capable(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && !q->limits.max_write_zeroes_sectors;
+}
+
+static bool dm_table_supports_write_zeroes(struct dm_table *t)
+{
+ struct dm_target *ti;
+ unsigned i = 0;
+
+ while (i < dm_table_get_num_targets(t)) {
+ ti = dm_table_get_target(t, i++);
+
+ if (!ti->num_write_zeroes_bios)
+ return false;
+
+ if (!ti->type->iterate_devices ||
+ ti->type->iterate_devices(ti, device_not_write_zeroes_capable, NULL))
+ return false;
+ }
+
+ return true;
+}
+
+static int device_not_discard_capable(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && !blk_queue_discard(q);
+}
+
+static bool dm_table_supports_discards(struct dm_table *t)
+{
+ struct dm_target *ti;
+ unsigned i;
+
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+
+ if (!ti->num_discard_bios)
+ return false;
+
+ /*
+ * Either the target provides discard support (as implied by setting
+ * 'discards_supported') or it relies on _all_ data devices having
+ * discard support.
+ */
+ if (!ti->discards_supported &&
+ (!ti->type->iterate_devices ||
+ ti->type->iterate_devices(ti, device_not_discard_capable, NULL)))
+ return false;
+ }
+
+ return true;
+}
+
+static int device_not_secure_erase_capable(struct dm_target *ti,
+ struct dm_dev *dev, sector_t start,
+ sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && !blk_queue_secure_erase(q);
+}
+
+static bool dm_table_supports_secure_erase(struct dm_table *t)
+{
+ struct dm_target *ti;
+ unsigned int i;
+
+ for (i = 0; i < dm_table_get_num_targets(t); i++) {
+ ti = dm_table_get_target(t, i);
+
+ if (!ti->num_secure_erase_bios)
+ return false;
+
+ if (!ti->type->iterate_devices ||
+ ti->type->iterate_devices(ti, device_not_secure_erase_capable, NULL))
+ return false;
+ }
+
+ return true;
+}
+
+void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
+ struct queue_limits *limits)
+{
+ bool wc = false, fua = false;
+
+ /*
+ * Copy table's limits to the DM device's request_queue
+ */
+ q->limits = *limits;
+
+ if (!dm_table_supports_discards(t)) {
+ blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q);
+ /* Must also clear discard limits... */
+ q->limits.max_discard_sectors = 0;
+ q->limits.max_hw_discard_sectors = 0;
+ q->limits.discard_granularity = 0;
+ q->limits.discard_alignment = 0;
+ q->limits.discard_misaligned = 0;
+ } else
+ blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
+
+ if (dm_table_supports_secure_erase(t))
+ blk_queue_flag_set(QUEUE_FLAG_SECERASE, q);
+
+ if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_WC))) {
+ wc = true;
+ if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_FUA)))
+ fua = true;
+ }
+ blk_queue_write_cache(q, wc, fua);
+
+ if (dm_table_supports_dax(t))
+ blk_queue_flag_set(QUEUE_FLAG_DAX, q);
+ else
+ blk_queue_flag_clear(QUEUE_FLAG_DAX, q);
+
+ if (dm_table_supports_dax_write_cache(t))
+ dax_write_cache(t->md->dax_dev, true);
+
+ /* Ensure that all underlying devices are non-rotational. */
+ if (dm_table_all_devices_attribute(t, device_is_nonrot))
+ blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
+ else
+ blk_queue_flag_clear(QUEUE_FLAG_NONROT, q);
+
+ if (!dm_table_supports_write_same(t))
+ q->limits.max_write_same_sectors = 0;
+ if (!dm_table_supports_write_zeroes(t))
+ q->limits.max_write_zeroes_sectors = 0;
+
+ if (dm_table_all_devices_attribute(t, queue_supports_sg_merge))
+ blk_queue_flag_clear(QUEUE_FLAG_NO_SG_MERGE, q);
+ else
+ blk_queue_flag_set(QUEUE_FLAG_NO_SG_MERGE, q);
+
+ dm_table_verify_integrity(t);
+
+ /*
+ * Determine whether or not this queue's I/O timings contribute
+ * to the entropy pool, Only request-based targets use this.
+ * Clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not
+ * have it set.
+ */
+ if (blk_queue_add_random(q) && dm_table_all_devices_attribute(t, device_is_not_random))
+ blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q);
+}
+
+unsigned int dm_table_get_num_targets(struct dm_table *t)
+{
+ return t->num_targets;
+}
+
+struct list_head *dm_table_get_devices(struct dm_table *t)
+{
+ return &t->devices;
+}
+
+fmode_t dm_table_get_mode(struct dm_table *t)
+{
+ return t->mode;
+}
+EXPORT_SYMBOL(dm_table_get_mode);
+
+enum suspend_mode {
+ PRESUSPEND,
+ PRESUSPEND_UNDO,
+ POSTSUSPEND,
+};
+
+static void suspend_targets(struct dm_table *t, enum suspend_mode mode)
+{
+ int i = t->num_targets;
+ struct dm_target *ti = t->targets;
+
+ lockdep_assert_held(&t->md->suspend_lock);
+
+ while (i--) {
+ switch (mode) {
+ case PRESUSPEND:
+ if (ti->type->presuspend)
+ ti->type->presuspend(ti);
+ break;
+ case PRESUSPEND_UNDO:
+ if (ti->type->presuspend_undo)
+ ti->type->presuspend_undo(ti);
+ break;
+ case POSTSUSPEND:
+ if (ti->type->postsuspend)
+ ti->type->postsuspend(ti);
+ break;
+ }
+ ti++;
+ }
+}
+
+void dm_table_presuspend_targets(struct dm_table *t)
+{
+ if (!t)
+ return;
+
+ suspend_targets(t, PRESUSPEND);
+}
+
+void dm_table_presuspend_undo_targets(struct dm_table *t)
+{
+ if (!t)
+ return;
+
+ suspend_targets(t, PRESUSPEND_UNDO);
+}
+
+void dm_table_postsuspend_targets(struct dm_table *t)
+{
+ if (!t)
+ return;
+
+ suspend_targets(t, POSTSUSPEND);
+}
+
+int dm_table_resume_targets(struct dm_table *t)
+{
+ int i, r = 0;
+
+ lockdep_assert_held(&t->md->suspend_lock);
+
+ for (i = 0; i < t->num_targets; i++) {
+ struct dm_target *ti = t->targets + i;
+
+ if (!ti->type->preresume)
+ continue;
+
+ r = ti->type->preresume(ti);
+ if (r) {
+ DMERR("%s: %s: preresume failed, error = %d",
+ dm_device_name(t->md), ti->type->name, r);
+ return r;
+ }
+ }
+
+ for (i = 0; i < t->num_targets; i++) {
+ struct dm_target *ti = t->targets + i;
+
+ if (ti->type->resume)
+ ti->type->resume(ti);
+ }
+
+ return 0;
+}
+
+void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb)
+{
+ list_add(&cb->list, &t->target_callbacks);
+}
+EXPORT_SYMBOL_GPL(dm_table_add_target_callbacks);
+
+int dm_table_any_congested(struct dm_table *t, int bdi_bits)
+{
+ struct dm_dev_internal *dd;
+ struct list_head *devices = dm_table_get_devices(t);
+ struct dm_target_callbacks *cb;
+ int r = 0;
+
+ list_for_each_entry(dd, devices, list) {
+ struct request_queue *q = bdev_get_queue(dd->dm_dev->bdev);
+ char b[BDEVNAME_SIZE];
+
+ if (likely(q))
+ r |= bdi_congested(q->backing_dev_info, bdi_bits);
+ else
+ DMWARN_LIMIT("%s: any_congested: nonexistent device %s",
+ dm_device_name(t->md),
+ bdevname(dd->dm_dev->bdev, b));
+ }
+
+ list_for_each_entry(cb, &t->target_callbacks, list)
+ if (cb->congested_fn)
+ r |= cb->congested_fn(cb, bdi_bits);
+
+ return r;
+}
+
+struct mapped_device *dm_table_get_md(struct dm_table *t)
+{
+ return t->md;
+}
+EXPORT_SYMBOL(dm_table_get_md);
+
+void dm_table_run_md_queue_async(struct dm_table *t)
+{
+ struct mapped_device *md;
+ struct request_queue *queue;
+ unsigned long flags;
+
+ if (!dm_table_request_based(t))
+ return;
+
+ md = dm_table_get_md(t);
+ queue = dm_get_md_queue(md);
+ if (queue) {
+ if (queue->mq_ops)
+ blk_mq_run_hw_queues(queue, true);
+ else {
+ spin_lock_irqsave(queue->queue_lock, flags);
+ blk_run_queue_async(queue);
+ spin_unlock_irqrestore(queue->queue_lock, flags);
+ }
+ }
+}
+EXPORT_SYMBOL(dm_table_run_md_queue_async);
+