![Jeff Moyer](/assets/img/avatar_default.png)
Commit 05f1dd5
("block: add queue flag for disabling SG merging")
introduced a new queue flag: QUEUE_FLAG_NO_SG_MERGE. This gets set by
default in blk_mq_init_queue for mq-enabled devices. The effect of
the flag is to bypass the SG segment merging. Instead, the
bio->bi_vcnt is used as the number of hardware segments.
With a device mapper target on top of a device with
QUEUE_FLAG_NO_SG_MERGE set, we can end up sending down more segments
than a driver is prepared to handle. I ran into this when backporting
the virtio_blk mq support. It triggerred this BUG_ON, in
virtio_queue_rq:
BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
The queue's max is set here:
blk_queue_max_segments(q, vblk->sg_elems-2);
Basically, what happens is that a bio is built up for the dm device
(which does not have the QUEUE_FLAG_NO_SG_MERGE flag set) using
bio_add_page. That path will call into __blk_recalc_rq_segments, so
what you end up with is bi_phys_segments being much smaller than bi_vcnt
(and bi_vcnt grows beyond the maximum sg elements). Then, when the bio
is submitted, it gets cloned. When the cloned bio is submitted, it will
end up in blk_recount_segments, here:
if (test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags))
bio->bi_phys_segments = bio->bi_vcnt;
and now we've set bio->bi_phys_segments to a number that is beyond what
was registered as queue_max_segments by the driver.
The right way to fix this is to propagate the queue flag up the stack.
The rules for propagating the flag are simple:
- if the flag is set for any underlying device, it must be set for the
upper device
- consequently, if the flag is not set for any underlying device, it
should not be set for the upper device.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # 3.16+
1689 lines
39 KiB
C
1689 lines
39 KiB
C
/*
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* Copyright (C) 2001 Sistina Software (UK) Limited.
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* Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
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*
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* This file is released under the GPL.
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*/
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#include "dm.h"
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#include <linux/module.h>
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#include <linux/vmalloc.h>
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#include <linux/blkdev.h>
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#include <linux/namei.h>
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#include <linux/ctype.h>
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#include <linux/string.h>
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#include <linux/slab.h>
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#include <linux/interrupt.h>
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#include <linux/mutex.h>
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#include <linux/delay.h>
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#include <linux/atomic.h>
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#define DM_MSG_PREFIX "table"
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#define MAX_DEPTH 16
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#define NODE_SIZE L1_CACHE_BYTES
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#define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
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#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
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struct dm_table {
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struct mapped_device *md;
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unsigned type;
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/* btree table */
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unsigned int depth;
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unsigned int counts[MAX_DEPTH]; /* in nodes */
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sector_t *index[MAX_DEPTH];
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unsigned int num_targets;
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unsigned int num_allocated;
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sector_t *highs;
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struct dm_target *targets;
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struct target_type *immutable_target_type;
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unsigned integrity_supported:1;
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unsigned singleton:1;
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/*
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* Indicates the rw permissions for the new logical
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* device. This should be a combination of FMODE_READ
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* and FMODE_WRITE.
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*/
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fmode_t mode;
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/* a list of devices used by this table */
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struct list_head devices;
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/* events get handed up using this callback */
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void (*event_fn)(void *);
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void *event_context;
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struct dm_md_mempools *mempools;
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struct list_head target_callbacks;
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};
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/*
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* Similar to ceiling(log_size(n))
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*/
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static unsigned int int_log(unsigned int n, unsigned int base)
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{
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int result = 0;
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while (n > 1) {
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n = dm_div_up(n, base);
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result++;
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}
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return result;
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}
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/*
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* Calculate the index of the child node of the n'th node k'th key.
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*/
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static inline unsigned int get_child(unsigned int n, unsigned int k)
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{
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return (n * CHILDREN_PER_NODE) + k;
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}
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/*
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* Return the n'th node of level l from table t.
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*/
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static inline sector_t *get_node(struct dm_table *t,
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unsigned int l, unsigned int n)
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{
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return t->index[l] + (n * KEYS_PER_NODE);
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}
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/*
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* Return the highest key that you could lookup from the n'th
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* node on level l of the btree.
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*/
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static sector_t high(struct dm_table *t, unsigned int l, unsigned int n)
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{
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for (; l < t->depth - 1; l++)
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n = get_child(n, CHILDREN_PER_NODE - 1);
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if (n >= t->counts[l])
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return (sector_t) - 1;
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return get_node(t, l, n)[KEYS_PER_NODE - 1];
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}
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/*
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* Fills in a level of the btree based on the highs of the level
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* below it.
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*/
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static int setup_btree_index(unsigned int l, struct dm_table *t)
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{
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unsigned int n, k;
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sector_t *node;
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for (n = 0U; n < t->counts[l]; n++) {
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node = get_node(t, l, n);
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for (k = 0U; k < KEYS_PER_NODE; k++)
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node[k] = high(t, l + 1, get_child(n, k));
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}
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return 0;
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}
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void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size)
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{
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unsigned long size;
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void *addr;
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/*
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* Check that we're not going to overflow.
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*/
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if (nmemb > (ULONG_MAX / elem_size))
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return NULL;
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size = nmemb * elem_size;
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addr = vzalloc(size);
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return addr;
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}
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EXPORT_SYMBOL(dm_vcalloc);
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/*
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* highs, and targets are managed as dynamic arrays during a
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* table load.
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*/
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static int alloc_targets(struct dm_table *t, unsigned int num)
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{
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sector_t *n_highs;
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struct dm_target *n_targets;
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/*
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* Allocate both the target array and offset array at once.
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* Append an empty entry to catch sectors beyond the end of
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* the device.
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*/
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n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) +
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sizeof(sector_t));
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if (!n_highs)
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return -ENOMEM;
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n_targets = (struct dm_target *) (n_highs + num);
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memset(n_highs, -1, sizeof(*n_highs) * num);
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vfree(t->highs);
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t->num_allocated = num;
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t->highs = n_highs;
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t->targets = n_targets;
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return 0;
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}
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int dm_table_create(struct dm_table **result, fmode_t mode,
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unsigned num_targets, struct mapped_device *md)
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{
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struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
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if (!t)
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return -ENOMEM;
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INIT_LIST_HEAD(&t->devices);
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INIT_LIST_HEAD(&t->target_callbacks);
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if (!num_targets)
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num_targets = KEYS_PER_NODE;
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num_targets = dm_round_up(num_targets, KEYS_PER_NODE);
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if (!num_targets) {
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kfree(t);
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return -ENOMEM;
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}
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if (alloc_targets(t, num_targets)) {
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kfree(t);
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return -ENOMEM;
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}
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t->mode = mode;
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t->md = md;
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*result = t;
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return 0;
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}
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static void free_devices(struct list_head *devices)
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{
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struct list_head *tmp, *next;
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list_for_each_safe(tmp, next, devices) {
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struct dm_dev_internal *dd =
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list_entry(tmp, struct dm_dev_internal, list);
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DMWARN("dm_table_destroy: dm_put_device call missing for %s",
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dd->dm_dev.name);
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kfree(dd);
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}
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}
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void dm_table_destroy(struct dm_table *t)
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{
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unsigned int i;
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if (!t)
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return;
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/* free the indexes */
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if (t->depth >= 2)
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vfree(t->index[t->depth - 2]);
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/* free the targets */
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for (i = 0; i < t->num_targets; i++) {
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struct dm_target *tgt = t->targets + i;
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if (tgt->type->dtr)
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tgt->type->dtr(tgt);
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dm_put_target_type(tgt->type);
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}
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vfree(t->highs);
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/* free the device list */
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free_devices(&t->devices);
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dm_free_md_mempools(t->mempools);
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kfree(t);
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}
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/*
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* See if we've already got a device in the list.
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*/
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static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev)
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{
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struct dm_dev_internal *dd;
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list_for_each_entry (dd, l, list)
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if (dd->dm_dev.bdev->bd_dev == dev)
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return dd;
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return NULL;
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}
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/*
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* Open a device so we can use it as a map destination.
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*/
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static int open_dev(struct dm_dev_internal *d, dev_t dev,
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struct mapped_device *md)
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{
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static char *_claim_ptr = "I belong to device-mapper";
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struct block_device *bdev;
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int r;
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BUG_ON(d->dm_dev.bdev);
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bdev = blkdev_get_by_dev(dev, d->dm_dev.mode | FMODE_EXCL, _claim_ptr);
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if (IS_ERR(bdev))
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return PTR_ERR(bdev);
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r = bd_link_disk_holder(bdev, dm_disk(md));
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if (r) {
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blkdev_put(bdev, d->dm_dev.mode | FMODE_EXCL);
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return r;
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}
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d->dm_dev.bdev = bdev;
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return 0;
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}
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/*
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* Close a device that we've been using.
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*/
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static void close_dev(struct dm_dev_internal *d, struct mapped_device *md)
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{
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if (!d->dm_dev.bdev)
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return;
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bd_unlink_disk_holder(d->dm_dev.bdev, dm_disk(md));
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blkdev_put(d->dm_dev.bdev, d->dm_dev.mode | FMODE_EXCL);
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d->dm_dev.bdev = NULL;
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}
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/*
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* If possible, this checks an area of a destination device is invalid.
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*/
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static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev,
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sector_t start, sector_t len, void *data)
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{
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struct request_queue *q;
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struct queue_limits *limits = data;
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struct block_device *bdev = dev->bdev;
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sector_t dev_size =
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i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
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unsigned short logical_block_size_sectors =
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limits->logical_block_size >> SECTOR_SHIFT;
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char b[BDEVNAME_SIZE];
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/*
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* Some devices exist without request functions,
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* such as loop devices not yet bound to backing files.
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* Forbid the use of such devices.
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*/
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q = bdev_get_queue(bdev);
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if (!q || !q->make_request_fn) {
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DMWARN("%s: %s is not yet initialised: "
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"start=%llu, len=%llu, dev_size=%llu",
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dm_device_name(ti->table->md), bdevname(bdev, b),
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(unsigned long long)start,
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(unsigned long long)len,
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(unsigned long long)dev_size);
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return 1;
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}
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if (!dev_size)
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return 0;
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if ((start >= dev_size) || (start + len > dev_size)) {
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DMWARN("%s: %s too small for target: "
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"start=%llu, len=%llu, dev_size=%llu",
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dm_device_name(ti->table->md), bdevname(bdev, b),
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(unsigned long long)start,
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(unsigned long long)len,
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(unsigned long long)dev_size);
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return 1;
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}
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if (logical_block_size_sectors <= 1)
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return 0;
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if (start & (logical_block_size_sectors - 1)) {
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DMWARN("%s: start=%llu not aligned to h/w "
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"logical block size %u of %s",
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dm_device_name(ti->table->md),
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(unsigned long long)start,
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limits->logical_block_size, bdevname(bdev, b));
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return 1;
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}
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if (len & (logical_block_size_sectors - 1)) {
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DMWARN("%s: len=%llu not aligned to h/w "
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"logical block size %u of %s",
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dm_device_name(ti->table->md),
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(unsigned long long)len,
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limits->logical_block_size, bdevname(bdev, b));
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return 1;
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}
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return 0;
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}
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/*
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* This upgrades the mode on an already open dm_dev, being
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* careful to leave things as they were if we fail to reopen the
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* device and not to touch the existing bdev field in case
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* it is accessed concurrently inside dm_table_any_congested().
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*/
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static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
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struct mapped_device *md)
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{
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int r;
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struct dm_dev_internal dd_new, dd_old;
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dd_new = dd_old = *dd;
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dd_new.dm_dev.mode |= new_mode;
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dd_new.dm_dev.bdev = NULL;
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r = open_dev(&dd_new, dd->dm_dev.bdev->bd_dev, md);
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if (r)
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return r;
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dd->dm_dev.mode |= new_mode;
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close_dev(&dd_old, md);
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return 0;
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}
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/*
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* Add a device to the list, or just increment the usage count if
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* it's already present.
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*/
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int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
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struct dm_dev **result)
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{
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int r;
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dev_t uninitialized_var(dev);
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struct dm_dev_internal *dd;
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unsigned int major, minor;
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struct dm_table *t = ti->table;
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char dummy;
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BUG_ON(!t);
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if (sscanf(path, "%u:%u%c", &major, &minor, &dummy) == 2) {
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/* Extract the major/minor numbers */
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dev = MKDEV(major, minor);
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if (MAJOR(dev) != major || MINOR(dev) != minor)
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return -EOVERFLOW;
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} else {
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/* convert the path to a device */
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struct block_device *bdev = lookup_bdev(path);
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if (IS_ERR(bdev))
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return PTR_ERR(bdev);
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dev = bdev->bd_dev;
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bdput(bdev);
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}
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dd = find_device(&t->devices, dev);
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if (!dd) {
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dd = kmalloc(sizeof(*dd), GFP_KERNEL);
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if (!dd)
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return -ENOMEM;
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dd->dm_dev.mode = mode;
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dd->dm_dev.bdev = NULL;
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if ((r = open_dev(dd, dev, t->md))) {
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kfree(dd);
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return r;
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}
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format_dev_t(dd->dm_dev.name, dev);
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atomic_set(&dd->count, 0);
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list_add(&dd->list, &t->devices);
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} else if (dd->dm_dev.mode != (mode | dd->dm_dev.mode)) {
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r = upgrade_mode(dd, mode, t->md);
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if (r)
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return r;
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}
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atomic_inc(&dd->count);
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*result = &dd->dm_dev;
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return 0;
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}
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EXPORT_SYMBOL(dm_get_device);
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static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
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sector_t start, sector_t len, void *data)
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{
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struct queue_limits *limits = data;
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struct block_device *bdev = dev->bdev;
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struct request_queue *q = bdev_get_queue(bdev);
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char b[BDEVNAME_SIZE];
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if (unlikely(!q)) {
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DMWARN("%s: Cannot set limits for nonexistent device %s",
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dm_device_name(ti->table->md), bdevname(bdev, b));
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return 0;
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}
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if (bdev_stack_limits(limits, bdev, start) < 0)
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DMWARN("%s: adding target device %s caused an alignment inconsistency: "
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"physical_block_size=%u, logical_block_size=%u, "
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"alignment_offset=%u, start=%llu",
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dm_device_name(ti->table->md), bdevname(bdev, b),
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q->limits.physical_block_size,
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q->limits.logical_block_size,
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q->limits.alignment_offset,
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(unsigned long long) start << SECTOR_SHIFT);
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/*
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* Check if merge fn is supported.
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* If not we'll force DM to use PAGE_SIZE or
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* smaller I/O, just to be safe.
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*/
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if (dm_queue_merge_is_compulsory(q) && !ti->type->merge)
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blk_limits_max_hw_sectors(limits,
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(unsigned int) (PAGE_SIZE >> 9));
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return 0;
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}
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/*
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* Decrement a device's use count and remove it if necessary.
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*/
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void dm_put_device(struct dm_target *ti, struct dm_dev *d)
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{
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struct dm_dev_internal *dd = container_of(d, struct dm_dev_internal,
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dm_dev);
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|
|
if (atomic_dec_and_test(&dd->count)) {
|
|
close_dev(dd, ti->table->md);
|
|
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 *array_size, char **old_argv)
|
|
{
|
|
char **argv;
|
|
unsigned new_size;
|
|
gfp_t gfp;
|
|
|
|
if (*array_size) {
|
|
new_size = *array_size * 2;
|
|
gfp = GFP_KERNEL;
|
|
} else {
|
|
new_size = 8;
|
|
gfp = GFP_NOIO;
|
|
}
|
|
argv = kmalloc(new_size * sizeof(*argv), gfp);
|
|
if (argv) {
|
|
memcpy(argv, old_argv, *array_size * sizeof(*argv));
|
|
*array_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 = 0;
|
|
|
|
/*
|
|
* Check each entry in the table in turn.
|
|
*/
|
|
while (i < dm_table_get_num_targets(table)) {
|
|
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) {
|
|
DMERR("%s: target type %s must appear alone in table",
|
|
dm_device_name(t->md), type);
|
|
return -EINVAL;
|
|
}
|
|
t->singleton = 1;
|
|
}
|
|
|
|
if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) {
|
|
DMERR("%s: target type %s may not be included in read-only tables",
|
|
dm_device_name(t->md), type);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (t->immutable_target_type) {
|
|
if (t->immutable_target_type != tgt->type) {
|
|
DMERR("%s: immutable target type %s cannot be mixed with other target types",
|
|
dm_device_name(t->md), t->immutable_target_type->name);
|
|
return -EINVAL;
|
|
}
|
|
} else if (dm_target_is_immutable(tgt->type)) {
|
|
if (t->num_targets) {
|
|
DMERR("%s: immutable target type %s cannot be mixed with other target types",
|
|
dm_device_name(t->md), tgt->type->name);
|
|
return -EINVAL;
|
|
}
|
|
t->immutable_target_type = tgt->type;
|
|
}
|
|
|
|
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";
|
|
r = -EINVAL;
|
|
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(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(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(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 int dm_table_set_type(struct dm_table *t)
|
|
{
|
|
unsigned i;
|
|
unsigned bio_based = 0, request_based = 0, hybrid = 0;
|
|
struct dm_target *tgt;
|
|
struct dm_dev_internal *dd;
|
|
struct list_head *devices;
|
|
unsigned live_md_type;
|
|
|
|
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) {
|
|
DMWARN("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.
|
|
*/
|
|
live_md_type = dm_get_md_type(t->md);
|
|
if (live_md_type == DM_TYPE_REQUEST_BASED)
|
|
request_based = 1;
|
|
else
|
|
bio_based = 1;
|
|
}
|
|
|
|
if (bio_based) {
|
|
/* We must use this table as bio-based */
|
|
t->type = DM_TYPE_BIO_BASED;
|
|
return 0;
|
|
}
|
|
|
|
BUG_ON(!request_based); /* No targets in this table */
|
|
|
|
/* Non-request-stackable devices can't be used for request-based dm */
|
|
devices = dm_table_get_devices(t);
|
|
list_for_each_entry(dd, devices, list) {
|
|
if (!blk_queue_stackable(bdev_get_queue(dd->dm_dev.bdev))) {
|
|
DMWARN("table load rejected: including"
|
|
" non-request-stackable devices");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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) {
|
|
DMWARN("Request-based dm doesn't support multiple targets yet");
|
|
return -EINVAL;
|
|
}
|
|
|
|
t->type = DM_TYPE_REQUEST_BASED;
|
|
|
|
return 0;
|
|
}
|
|
|
|
unsigned 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;
|
|
}
|
|
|
|
bool dm_table_request_based(struct dm_table *t)
|
|
{
|
|
return dm_table_get_type(t) == DM_TYPE_REQUEST_BASED;
|
|
}
|
|
|
|
static int dm_table_alloc_md_mempools(struct dm_table *t)
|
|
{
|
|
unsigned type = dm_table_get_type(t);
|
|
unsigned per_bio_data_size = 0;
|
|
struct dm_target *tgt;
|
|
unsigned i;
|
|
|
|
if (unlikely(type == DM_TYPE_NONE)) {
|
|
DMWARN("no table type is set, can't allocate mempools");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (type == DM_TYPE_BIO_BASED)
|
|
for (i = 0; i < t->num_targets; i++) {
|
|
tgt = t->targets + i;
|
|
per_bio_data_size = max(per_bio_data_size, tgt->per_bio_data_size);
|
|
}
|
|
|
|
t->mempools = dm_alloc_md_mempools(type, t->integrity_supported, per_bio_data_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;
|
|
}
|
|
|
|
/*
|
|
* Get a disk whose integrity profile reflects the table's profile.
|
|
* If %match_all is true, all devices' profiles must match.
|
|
* If %match_all is false, all devices must at least have an
|
|
* allocated integrity profile; but uninitialized is ok.
|
|
* Returns NULL if integrity support was inconsistent or unavailable.
|
|
*/
|
|
static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t,
|
|
bool match_all)
|
|
{
|
|
struct list_head *devices = dm_table_get_devices(t);
|
|
struct dm_dev_internal *dd = NULL;
|
|
struct gendisk *prev_disk = NULL, *template_disk = NULL;
|
|
|
|
list_for_each_entry(dd, devices, list) {
|
|
template_disk = dd->dm_dev.bdev->bd_disk;
|
|
if (!blk_get_integrity(template_disk))
|
|
goto no_integrity;
|
|
if (!match_all && !blk_integrity_is_initialized(template_disk))
|
|
continue; /* skip uninitialized profiles */
|
|
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).
|
|
* Stacked DM devices force a 2 stage integrity profile validation:
|
|
* 1 - during load, validate all initialized integrity profiles match
|
|
* 2 - during resume, validate all integrity profiles match
|
|
*/
|
|
static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md)
|
|
{
|
|
struct gendisk *template_disk = NULL;
|
|
|
|
template_disk = dm_table_get_integrity_disk(t, false);
|
|
if (!template_disk)
|
|
return 0;
|
|
|
|
if (!blk_integrity_is_initialized(dm_disk(md))) {
|
|
t->integrity_supported = 1;
|
|
return blk_integrity_register(dm_disk(md), NULL);
|
|
}
|
|
|
|
/*
|
|
* If DM device already has an initalized integrity
|
|
* profile the new profile should not conflict.
|
|
*/
|
|
if (blk_integrity_is_initialized(template_disk) &&
|
|
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 initialized integrity profile */
|
|
t->integrity_supported = 1;
|
|
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_set_type(t);
|
|
if (r) {
|
|
DMERR("unable to set table type");
|
|
return r;
|
|
}
|
|
|
|
r = dm_table_build_index(t);
|
|
if (r) {
|
|
DMERR("unable to build btrees");
|
|
return r;
|
|
}
|
|
|
|
r = dm_table_prealloc_integrity(t, t->md);
|
|
if (r) {
|
|
DMERR("could not register integrity profile.");
|
|
return r;
|
|
}
|
|
|
|
r = dm_table_alloc_md_mempools(t);
|
|
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 *uninitialized_var(ti);
|
|
unsigned i = 0, num_devices = 0;
|
|
|
|
while (i < dm_table_get_num_targets(table)) {
|
|
ti = dm_table_get_target(table, i++);
|
|
|
|
if (!ti->type->iterate_devices)
|
|
return false;
|
|
|
|
ti->type->iterate_devices(ti, count_device, &num_devices);
|
|
if (num_devices)
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* 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 *uninitialized_var(ti);
|
|
struct queue_limits ti_limits;
|
|
unsigned i = 0;
|
|
|
|
blk_set_stacking_limits(limits);
|
|
|
|
while (i < dm_table_get_num_targets(table)) {
|
|
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);
|
|
|
|
/* 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);
|
|
}
|
|
|
|
return validate_hardware_logical_block_alignment(table, limits);
|
|
}
|
|
|
|
/*
|
|
* Set the integrity profile for this device if all devices used have
|
|
* matching profiles. We're quite deep in the resume path but still
|
|
* don't know if all devices (particularly DM devices this device
|
|
* may be stacked on) have matching profiles. Even if the profiles
|
|
* don't match we have no way to fail (to resume) at this point.
|
|
*/
|
|
static void dm_table_set_integrity(struct dm_table *t)
|
|
{
|
|
struct gendisk *template_disk = NULL;
|
|
|
|
if (!blk_get_integrity(dm_disk(t->md)))
|
|
return;
|
|
|
|
template_disk = dm_table_get_integrity_disk(t, true);
|
|
if (template_disk)
|
|
blk_integrity_register(dm_disk(t->md),
|
|
blk_get_integrity(template_disk));
|
|
else if (blk_integrity_is_initialized(dm_disk(t->md)))
|
|
DMWARN("%s: device no longer has a valid integrity profile",
|
|
dm_device_name(t->md));
|
|
else
|
|
DMWARN("%s: unable to establish an integrity profile",
|
|
dm_device_name(t->md));
|
|
}
|
|
|
|
static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
|
|
sector_t start, sector_t len, void *data)
|
|
{
|
|
unsigned flush = (*(unsigned *)data);
|
|
struct request_queue *q = bdev_get_queue(dev->bdev);
|
|
|
|
return q && (q->flush_flags & flush);
|
|
}
|
|
|
|
static bool dm_table_supports_flush(struct dm_table *t, unsigned flush)
|
|
{
|
|
struct dm_target *ti;
|
|
unsigned i = 0;
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
while (i < dm_table_get_num_targets(t)) {
|
|
ti = dm_table_get_target(t, i++);
|
|
|
|
if (!ti->num_flush_bios)
|
|
continue;
|
|
|
|
if (ti->flush_supported)
|
|
return 1;
|
|
|
|
if (ti->type->iterate_devices &&
|
|
ti->type->iterate_devices(ti, device_flush_capable, &flush))
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool dm_table_discard_zeroes_data(struct dm_table *t)
|
|
{
|
|
struct dm_target *ti;
|
|
unsigned i = 0;
|
|
|
|
/* Ensure that all targets supports discard_zeroes_data. */
|
|
while (i < dm_table_get_num_targets(t)) {
|
|
ti = dm_table_get_target(t, i++);
|
|
|
|
if (ti->discard_zeroes_data_unsupported)
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
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 = 0;
|
|
|
|
while (i < dm_table_get_num_targets(t)) {
|
|
ti = dm_table_get_target(t, i++);
|
|
|
|
if (!ti->type->iterate_devices ||
|
|
!ti->type->iterate_devices(ti, func, NULL))
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
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 = 0;
|
|
|
|
while (i < dm_table_get_num_targets(t)) {
|
|
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_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 = 0;
|
|
|
|
/*
|
|
* Unless any target used by the table set discards_supported,
|
|
* require at least one underlying device to support discards.
|
|
* t->devices includes internal dm devices such as mirror logs
|
|
* so we need to use iterate_devices here, which targets
|
|
* supporting discard selectively must provide.
|
|
*/
|
|
while (i < dm_table_get_num_targets(t)) {
|
|
ti = dm_table_get_target(t, i++);
|
|
|
|
if (!ti->num_discard_bios)
|
|
continue;
|
|
|
|
if (ti->discards_supported)
|
|
return 1;
|
|
|
|
if (ti->type->iterate_devices &&
|
|
ti->type->iterate_devices(ti, device_discard_capable, NULL))
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
|
|
struct queue_limits *limits)
|
|
{
|
|
unsigned flush = 0;
|
|
|
|
/*
|
|
* Copy table's limits to the DM device's request_queue
|
|
*/
|
|
q->limits = *limits;
|
|
|
|
if (!dm_table_supports_discards(t))
|
|
queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
|
|
else
|
|
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
|
|
|
|
if (dm_table_supports_flush(t, REQ_FLUSH)) {
|
|
flush |= REQ_FLUSH;
|
|
if (dm_table_supports_flush(t, REQ_FUA))
|
|
flush |= REQ_FUA;
|
|
}
|
|
blk_queue_flush(q, flush);
|
|
|
|
if (!dm_table_discard_zeroes_data(t))
|
|
q->limits.discard_zeroes_data = 0;
|
|
|
|
/* Ensure that all underlying devices are non-rotational. */
|
|
if (dm_table_all_devices_attribute(t, device_is_nonrot))
|
|
queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
|
|
else
|
|
queue_flag_clear_unlocked(QUEUE_FLAG_NONROT, q);
|
|
|
|
if (!dm_table_supports_write_same(t))
|
|
q->limits.max_write_same_sectors = 0;
|
|
|
|
if (dm_table_all_devices_attribute(t, queue_supports_sg_merge))
|
|
queue_flag_clear_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);
|
|
else
|
|
queue_flag_set_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);
|
|
|
|
dm_table_set_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))
|
|
queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, q);
|
|
|
|
/*
|
|
* QUEUE_FLAG_STACKABLE must be set after all queue settings are
|
|
* visible to other CPUs because, once the flag is set, incoming bios
|
|
* are processed by request-based dm, which refers to the queue
|
|
* settings.
|
|
* Until the flag set, bios are passed to bio-based dm and queued to
|
|
* md->deferred where queue settings are not needed yet.
|
|
* Those bios are passed to request-based dm at the resume time.
|
|
*/
|
|
smp_mb();
|
|
if (dm_table_request_based(t))
|
|
queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, 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);
|
|
|
|
static void suspend_targets(struct dm_table *t, unsigned postsuspend)
|
|
{
|
|
int i = t->num_targets;
|
|
struct dm_target *ti = t->targets;
|
|
|
|
while (i--) {
|
|
if (postsuspend) {
|
|
if (ti->type->postsuspend)
|
|
ti->type->postsuspend(ti);
|
|
} else if (ti->type->presuspend)
|
|
ti->type->presuspend(ti);
|
|
|
|
ti++;
|
|
}
|
|
}
|
|
|
|
void dm_table_presuspend_targets(struct dm_table *t)
|
|
{
|
|
if (!t)
|
|
return;
|
|
|
|
suspend_targets(t, 0);
|
|
}
|
|
|
|
void dm_table_postsuspend_targets(struct dm_table *t)
|
|
{
|
|
if (!t)
|
|
return;
|
|
|
|
suspend_targets(t, 1);
|
|
}
|
|
|
|
int dm_table_resume_targets(struct dm_table *t)
|
|
{
|
|
int i, r = 0;
|
|
|
|
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;
|
|
}
|
|
|
|
int dm_table_any_busy_target(struct dm_table *t)
|
|
{
|
|
unsigned i;
|
|
struct dm_target *ti;
|
|
|
|
for (i = 0; i < t->num_targets; i++) {
|
|
ti = t->targets + i;
|
|
if (ti->type->busy && ti->type->busy(ti))
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
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) {
|
|
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);
|
|
|