Revision 73223e4e2e3867ebf033a5a8eb2e5df0158ccc99 authored by zhong jiang on 18 August 2017, 22:16:24 UTC, committed by Linus Torvalds on 18 August 2017, 22:32:02 UTC
I hit a use after free issue when executing trinity and repoduced it with KASAN enabled. The related call trace is as follows. BUG: KASan: use after free in SyS_get_mempolicy+0x3c8/0x960 at addr ffff8801f582d766 Read of size 2 by task syz-executor1/798 INFO: Allocated in mpol_new.part.2+0x74/0x160 age=3 cpu=1 pid=799 __slab_alloc+0x768/0x970 kmem_cache_alloc+0x2e7/0x450 mpol_new.part.2+0x74/0x160 mpol_new+0x66/0x80 SyS_mbind+0x267/0x9f0 system_call_fastpath+0x16/0x1b INFO: Freed in __mpol_put+0x2b/0x40 age=4 cpu=1 pid=799 __slab_free+0x495/0x8e0 kmem_cache_free+0x2f3/0x4c0 __mpol_put+0x2b/0x40 SyS_mbind+0x383/0x9f0 system_call_fastpath+0x16/0x1b INFO: Slab 0xffffea0009cb8dc0 objects=23 used=8 fp=0xffff8801f582de40 flags=0x200000000004080 INFO: Object 0xffff8801f582d760 @offset=5984 fp=0xffff8801f582d600 Bytes b4 ffff8801f582d750: ae 01 ff ff 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a ........ZZZZZZZZ Object ffff8801f582d760: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff8801f582d770: 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkk. Redzone ffff8801f582d778: bb bb bb bb bb bb bb bb ........ Padding ffff8801f582d8b8: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ Memory state around the buggy address: ffff8801f582d600: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801f582d680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8801f582d700: fc fc fc fc fc fc fc fc fc fc fc fc fb fb fb fc !shared memory policy is not protected against parallel removal by other thread which is normally protected by the mmap_sem. do_get_mempolicy, however, drops the lock midway while we can still access it later. Early premature up_read is a historical artifact from times when put_user was called in this path see https://lwn.net/Articles/124754/ but that is gone since 8bccd85ffbaf ("[PATCH] Implement sys_* do_* layering in the memory policy layer."). but when we have the the current mempolicy ref count model. The issue was introduced accordingly. Fix the issue by removing the premature release. Link: http://lkml.kernel.org/r/1502950924-27521-1-git-send-email-zhongjiang@huawei.com Signed-off-by: zhong jiang <zhongjiang@huawei.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: <stable@vger.kernel.org> [2.6+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent da094e4
blk-mq-debugfs.c
/*
* Copyright (C) 2017 Facebook
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include <linux/kernel.h>
#include <linux/blkdev.h>
#include <linux/debugfs.h>
#include <linux/blk-mq.h>
#include "blk.h"
#include "blk-mq.h"
#include "blk-mq-debugfs.h"
#include "blk-mq-tag.h"
static int blk_flags_show(struct seq_file *m, const unsigned long flags,
const char *const *flag_name, int flag_name_count)
{
bool sep = false;
int i;
for (i = 0; i < sizeof(flags) * BITS_PER_BYTE; i++) {
if (!(flags & BIT(i)))
continue;
if (sep)
seq_puts(m, "|");
sep = true;
if (i < flag_name_count && flag_name[i])
seq_puts(m, flag_name[i]);
else
seq_printf(m, "%d", i);
}
return 0;
}
#define QUEUE_FLAG_NAME(name) [QUEUE_FLAG_##name] = #name
static const char *const blk_queue_flag_name[] = {
QUEUE_FLAG_NAME(QUEUED),
QUEUE_FLAG_NAME(STOPPED),
QUEUE_FLAG_NAME(SYNCFULL),
QUEUE_FLAG_NAME(ASYNCFULL),
QUEUE_FLAG_NAME(DYING),
QUEUE_FLAG_NAME(BYPASS),
QUEUE_FLAG_NAME(BIDI),
QUEUE_FLAG_NAME(NOMERGES),
QUEUE_FLAG_NAME(SAME_COMP),
QUEUE_FLAG_NAME(FAIL_IO),
QUEUE_FLAG_NAME(STACKABLE),
QUEUE_FLAG_NAME(NONROT),
QUEUE_FLAG_NAME(IO_STAT),
QUEUE_FLAG_NAME(DISCARD),
QUEUE_FLAG_NAME(NOXMERGES),
QUEUE_FLAG_NAME(ADD_RANDOM),
QUEUE_FLAG_NAME(SECERASE),
QUEUE_FLAG_NAME(SAME_FORCE),
QUEUE_FLAG_NAME(DEAD),
QUEUE_FLAG_NAME(INIT_DONE),
QUEUE_FLAG_NAME(NO_SG_MERGE),
QUEUE_FLAG_NAME(POLL),
QUEUE_FLAG_NAME(WC),
QUEUE_FLAG_NAME(FUA),
QUEUE_FLAG_NAME(FLUSH_NQ),
QUEUE_FLAG_NAME(DAX),
QUEUE_FLAG_NAME(STATS),
QUEUE_FLAG_NAME(POLL_STATS),
QUEUE_FLAG_NAME(REGISTERED),
};
#undef QUEUE_FLAG_NAME
static int queue_state_show(void *data, struct seq_file *m)
{
struct request_queue *q = data;
blk_flags_show(m, q->queue_flags, blk_queue_flag_name,
ARRAY_SIZE(blk_queue_flag_name));
seq_puts(m, "\n");
return 0;
}
static ssize_t queue_state_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct request_queue *q = data;
char opbuf[16] = { }, *op;
/*
* The "state" attribute is removed after blk_cleanup_queue() has called
* blk_mq_free_queue(). Return if QUEUE_FLAG_DEAD has been set to avoid
* triggering a use-after-free.
*/
if (blk_queue_dead(q))
return -ENOENT;
if (count >= sizeof(opbuf)) {
pr_err("%s: operation too long\n", __func__);
goto inval;
}
if (copy_from_user(opbuf, buf, count))
return -EFAULT;
op = strstrip(opbuf);
if (strcmp(op, "run") == 0) {
blk_mq_run_hw_queues(q, true);
} else if (strcmp(op, "start") == 0) {
blk_mq_start_stopped_hw_queues(q, true);
} else if (strcmp(op, "kick") == 0) {
blk_mq_kick_requeue_list(q);
} else {
pr_err("%s: unsupported operation '%s'\n", __func__, op);
inval:
pr_err("%s: use 'run', 'start' or 'kick'\n", __func__);
return -EINVAL;
}
return count;
}
static void print_stat(struct seq_file *m, struct blk_rq_stat *stat)
{
if (stat->nr_samples) {
seq_printf(m, "samples=%d, mean=%lld, min=%llu, max=%llu",
stat->nr_samples, stat->mean, stat->min, stat->max);
} else {
seq_puts(m, "samples=0");
}
}
static int queue_write_hint_show(void *data, struct seq_file *m)
{
struct request_queue *q = data;
int i;
for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
seq_printf(m, "hint%d: %llu\n", i, q->write_hints[i]);
return 0;
}
static ssize_t queue_write_hint_store(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct request_queue *q = data;
int i;
for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
q->write_hints[i] = 0;
return count;
}
static int queue_poll_stat_show(void *data, struct seq_file *m)
{
struct request_queue *q = data;
int bucket;
for (bucket = 0; bucket < BLK_MQ_POLL_STATS_BKTS/2; bucket++) {
seq_printf(m, "read (%d Bytes): ", 1 << (9+bucket));
print_stat(m, &q->poll_stat[2*bucket]);
seq_puts(m, "\n");
seq_printf(m, "write (%d Bytes): ", 1 << (9+bucket));
print_stat(m, &q->poll_stat[2*bucket+1]);
seq_puts(m, "\n");
}
return 0;
}
#define HCTX_STATE_NAME(name) [BLK_MQ_S_##name] = #name
static const char *const hctx_state_name[] = {
HCTX_STATE_NAME(STOPPED),
HCTX_STATE_NAME(TAG_ACTIVE),
HCTX_STATE_NAME(SCHED_RESTART),
HCTX_STATE_NAME(TAG_WAITING),
HCTX_STATE_NAME(START_ON_RUN),
};
#undef HCTX_STATE_NAME
static int hctx_state_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
blk_flags_show(m, hctx->state, hctx_state_name,
ARRAY_SIZE(hctx_state_name));
seq_puts(m, "\n");
return 0;
}
#define BLK_TAG_ALLOC_NAME(name) [BLK_TAG_ALLOC_##name] = #name
static const char *const alloc_policy_name[] = {
BLK_TAG_ALLOC_NAME(FIFO),
BLK_TAG_ALLOC_NAME(RR),
};
#undef BLK_TAG_ALLOC_NAME
#define HCTX_FLAG_NAME(name) [ilog2(BLK_MQ_F_##name)] = #name
static const char *const hctx_flag_name[] = {
HCTX_FLAG_NAME(SHOULD_MERGE),
HCTX_FLAG_NAME(TAG_SHARED),
HCTX_FLAG_NAME(SG_MERGE),
HCTX_FLAG_NAME(BLOCKING),
HCTX_FLAG_NAME(NO_SCHED),
};
#undef HCTX_FLAG_NAME
static int hctx_flags_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
const int alloc_policy = BLK_MQ_FLAG_TO_ALLOC_POLICY(hctx->flags);
seq_puts(m, "alloc_policy=");
if (alloc_policy < ARRAY_SIZE(alloc_policy_name) &&
alloc_policy_name[alloc_policy])
seq_puts(m, alloc_policy_name[alloc_policy]);
else
seq_printf(m, "%d", alloc_policy);
seq_puts(m, " ");
blk_flags_show(m,
hctx->flags ^ BLK_ALLOC_POLICY_TO_MQ_FLAG(alloc_policy),
hctx_flag_name, ARRAY_SIZE(hctx_flag_name));
seq_puts(m, "\n");
return 0;
}
#define REQ_OP_NAME(name) [REQ_OP_##name] = #name
static const char *const op_name[] = {
REQ_OP_NAME(READ),
REQ_OP_NAME(WRITE),
REQ_OP_NAME(FLUSH),
REQ_OP_NAME(DISCARD),
REQ_OP_NAME(ZONE_REPORT),
REQ_OP_NAME(SECURE_ERASE),
REQ_OP_NAME(ZONE_RESET),
REQ_OP_NAME(WRITE_SAME),
REQ_OP_NAME(WRITE_ZEROES),
REQ_OP_NAME(SCSI_IN),
REQ_OP_NAME(SCSI_OUT),
REQ_OP_NAME(DRV_IN),
REQ_OP_NAME(DRV_OUT),
};
#undef REQ_OP_NAME
#define CMD_FLAG_NAME(name) [__REQ_##name] = #name
static const char *const cmd_flag_name[] = {
CMD_FLAG_NAME(FAILFAST_DEV),
CMD_FLAG_NAME(FAILFAST_TRANSPORT),
CMD_FLAG_NAME(FAILFAST_DRIVER),
CMD_FLAG_NAME(SYNC),
CMD_FLAG_NAME(META),
CMD_FLAG_NAME(PRIO),
CMD_FLAG_NAME(NOMERGE),
CMD_FLAG_NAME(IDLE),
CMD_FLAG_NAME(INTEGRITY),
CMD_FLAG_NAME(FUA),
CMD_FLAG_NAME(PREFLUSH),
CMD_FLAG_NAME(RAHEAD),
CMD_FLAG_NAME(BACKGROUND),
CMD_FLAG_NAME(NOUNMAP),
};
#undef CMD_FLAG_NAME
#define RQF_NAME(name) [ilog2((__force u32)RQF_##name)] = #name
static const char *const rqf_name[] = {
RQF_NAME(SORTED),
RQF_NAME(STARTED),
RQF_NAME(QUEUED),
RQF_NAME(SOFTBARRIER),
RQF_NAME(FLUSH_SEQ),
RQF_NAME(MIXED_MERGE),
RQF_NAME(MQ_INFLIGHT),
RQF_NAME(DONTPREP),
RQF_NAME(PREEMPT),
RQF_NAME(COPY_USER),
RQF_NAME(FAILED),
RQF_NAME(QUIET),
RQF_NAME(ELVPRIV),
RQF_NAME(IO_STAT),
RQF_NAME(ALLOCED),
RQF_NAME(PM),
RQF_NAME(HASHED),
RQF_NAME(STATS),
RQF_NAME(SPECIAL_PAYLOAD),
};
#undef RQF_NAME
#define RQAF_NAME(name) [REQ_ATOM_##name] = #name
static const char *const rqaf_name[] = {
RQAF_NAME(COMPLETE),
RQAF_NAME(STARTED),
RQAF_NAME(POLL_SLEPT),
};
#undef RQAF_NAME
int __blk_mq_debugfs_rq_show(struct seq_file *m, struct request *rq)
{
const struct blk_mq_ops *const mq_ops = rq->q->mq_ops;
const unsigned int op = rq->cmd_flags & REQ_OP_MASK;
seq_printf(m, "%p {.op=", rq);
if (op < ARRAY_SIZE(op_name) && op_name[op])
seq_printf(m, "%s", op_name[op]);
else
seq_printf(m, "%d", op);
seq_puts(m, ", .cmd_flags=");
blk_flags_show(m, rq->cmd_flags & ~REQ_OP_MASK, cmd_flag_name,
ARRAY_SIZE(cmd_flag_name));
seq_puts(m, ", .rq_flags=");
blk_flags_show(m, (__force unsigned int)rq->rq_flags, rqf_name,
ARRAY_SIZE(rqf_name));
seq_puts(m, ", .atomic_flags=");
blk_flags_show(m, rq->atomic_flags, rqaf_name, ARRAY_SIZE(rqaf_name));
seq_printf(m, ", .tag=%d, .internal_tag=%d", rq->tag,
rq->internal_tag);
if (mq_ops->show_rq)
mq_ops->show_rq(m, rq);
seq_puts(m, "}\n");
return 0;
}
EXPORT_SYMBOL_GPL(__blk_mq_debugfs_rq_show);
int blk_mq_debugfs_rq_show(struct seq_file *m, void *v)
{
return __blk_mq_debugfs_rq_show(m, list_entry_rq(v));
}
EXPORT_SYMBOL_GPL(blk_mq_debugfs_rq_show);
static void *queue_requeue_list_start(struct seq_file *m, loff_t *pos)
__acquires(&q->requeue_lock)
{
struct request_queue *q = m->private;
spin_lock_irq(&q->requeue_lock);
return seq_list_start(&q->requeue_list, *pos);
}
static void *queue_requeue_list_next(struct seq_file *m, void *v, loff_t *pos)
{
struct request_queue *q = m->private;
return seq_list_next(v, &q->requeue_list, pos);
}
static void queue_requeue_list_stop(struct seq_file *m, void *v)
__releases(&q->requeue_lock)
{
struct request_queue *q = m->private;
spin_unlock_irq(&q->requeue_lock);
}
static const struct seq_operations queue_requeue_list_seq_ops = {
.start = queue_requeue_list_start,
.next = queue_requeue_list_next,
.stop = queue_requeue_list_stop,
.show = blk_mq_debugfs_rq_show,
};
static void *hctx_dispatch_start(struct seq_file *m, loff_t *pos)
__acquires(&hctx->lock)
{
struct blk_mq_hw_ctx *hctx = m->private;
spin_lock(&hctx->lock);
return seq_list_start(&hctx->dispatch, *pos);
}
static void *hctx_dispatch_next(struct seq_file *m, void *v, loff_t *pos)
{
struct blk_mq_hw_ctx *hctx = m->private;
return seq_list_next(v, &hctx->dispatch, pos);
}
static void hctx_dispatch_stop(struct seq_file *m, void *v)
__releases(&hctx->lock)
{
struct blk_mq_hw_ctx *hctx = m->private;
spin_unlock(&hctx->lock);
}
static const struct seq_operations hctx_dispatch_seq_ops = {
.start = hctx_dispatch_start,
.next = hctx_dispatch_next,
.stop = hctx_dispatch_stop,
.show = blk_mq_debugfs_rq_show,
};
struct show_busy_params {
struct seq_file *m;
struct blk_mq_hw_ctx *hctx;
};
/*
* Note: the state of a request may change while this function is in progress,
* e.g. due to a concurrent blk_mq_finish_request() call.
*/
static void hctx_show_busy_rq(struct request *rq, void *data, bool reserved)
{
const struct show_busy_params *params = data;
if (blk_mq_map_queue(rq->q, rq->mq_ctx->cpu) == params->hctx &&
test_bit(REQ_ATOM_STARTED, &rq->atomic_flags))
__blk_mq_debugfs_rq_show(params->m,
list_entry_rq(&rq->queuelist));
}
static int hctx_busy_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
struct show_busy_params params = { .m = m, .hctx = hctx };
blk_mq_tagset_busy_iter(hctx->queue->tag_set, hctx_show_busy_rq,
¶ms);
return 0;
}
static int hctx_ctx_map_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
sbitmap_bitmap_show(&hctx->ctx_map, m);
return 0;
}
static void blk_mq_debugfs_tags_show(struct seq_file *m,
struct blk_mq_tags *tags)
{
seq_printf(m, "nr_tags=%u\n", tags->nr_tags);
seq_printf(m, "nr_reserved_tags=%u\n", tags->nr_reserved_tags);
seq_printf(m, "active_queues=%d\n",
atomic_read(&tags->active_queues));
seq_puts(m, "\nbitmap_tags:\n");
sbitmap_queue_show(&tags->bitmap_tags, m);
if (tags->nr_reserved_tags) {
seq_puts(m, "\nbreserved_tags:\n");
sbitmap_queue_show(&tags->breserved_tags, m);
}
}
static int hctx_tags_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
struct request_queue *q = hctx->queue;
int res;
res = mutex_lock_interruptible(&q->sysfs_lock);
if (res)
goto out;
if (hctx->tags)
blk_mq_debugfs_tags_show(m, hctx->tags);
mutex_unlock(&q->sysfs_lock);
out:
return res;
}
static int hctx_tags_bitmap_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
struct request_queue *q = hctx->queue;
int res;
res = mutex_lock_interruptible(&q->sysfs_lock);
if (res)
goto out;
if (hctx->tags)
sbitmap_bitmap_show(&hctx->tags->bitmap_tags.sb, m);
mutex_unlock(&q->sysfs_lock);
out:
return res;
}
static int hctx_sched_tags_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
struct request_queue *q = hctx->queue;
int res;
res = mutex_lock_interruptible(&q->sysfs_lock);
if (res)
goto out;
if (hctx->sched_tags)
blk_mq_debugfs_tags_show(m, hctx->sched_tags);
mutex_unlock(&q->sysfs_lock);
out:
return res;
}
static int hctx_sched_tags_bitmap_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
struct request_queue *q = hctx->queue;
int res;
res = mutex_lock_interruptible(&q->sysfs_lock);
if (res)
goto out;
if (hctx->sched_tags)
sbitmap_bitmap_show(&hctx->sched_tags->bitmap_tags.sb, m);
mutex_unlock(&q->sysfs_lock);
out:
return res;
}
static int hctx_io_poll_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
seq_printf(m, "considered=%lu\n", hctx->poll_considered);
seq_printf(m, "invoked=%lu\n", hctx->poll_invoked);
seq_printf(m, "success=%lu\n", hctx->poll_success);
return 0;
}
static ssize_t hctx_io_poll_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_hw_ctx *hctx = data;
hctx->poll_considered = hctx->poll_invoked = hctx->poll_success = 0;
return count;
}
static int hctx_dispatched_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
int i;
seq_printf(m, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER - 1; i++) {
unsigned int d = 1U << (i - 1);
seq_printf(m, "%8u\t%lu\n", d, hctx->dispatched[i]);
}
seq_printf(m, "%8u+\t%lu\n", 1U << (i - 1), hctx->dispatched[i]);
return 0;
}
static ssize_t hctx_dispatched_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_hw_ctx *hctx = data;
int i;
for (i = 0; i < BLK_MQ_MAX_DISPATCH_ORDER; i++)
hctx->dispatched[i] = 0;
return count;
}
static int hctx_queued_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
seq_printf(m, "%lu\n", hctx->queued);
return 0;
}
static ssize_t hctx_queued_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_hw_ctx *hctx = data;
hctx->queued = 0;
return count;
}
static int hctx_run_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
seq_printf(m, "%lu\n", hctx->run);
return 0;
}
static ssize_t hctx_run_write(void *data, const char __user *buf, size_t count,
loff_t *ppos)
{
struct blk_mq_hw_ctx *hctx = data;
hctx->run = 0;
return count;
}
static int hctx_active_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
seq_printf(m, "%d\n", atomic_read(&hctx->nr_active));
return 0;
}
static void *ctx_rq_list_start(struct seq_file *m, loff_t *pos)
__acquires(&ctx->lock)
{
struct blk_mq_ctx *ctx = m->private;
spin_lock(&ctx->lock);
return seq_list_start(&ctx->rq_list, *pos);
}
static void *ctx_rq_list_next(struct seq_file *m, void *v, loff_t *pos)
{
struct blk_mq_ctx *ctx = m->private;
return seq_list_next(v, &ctx->rq_list, pos);
}
static void ctx_rq_list_stop(struct seq_file *m, void *v)
__releases(&ctx->lock)
{
struct blk_mq_ctx *ctx = m->private;
spin_unlock(&ctx->lock);
}
static const struct seq_operations ctx_rq_list_seq_ops = {
.start = ctx_rq_list_start,
.next = ctx_rq_list_next,
.stop = ctx_rq_list_stop,
.show = blk_mq_debugfs_rq_show,
};
static int ctx_dispatched_show(void *data, struct seq_file *m)
{
struct blk_mq_ctx *ctx = data;
seq_printf(m, "%lu %lu\n", ctx->rq_dispatched[1], ctx->rq_dispatched[0]);
return 0;
}
static ssize_t ctx_dispatched_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_ctx *ctx = data;
ctx->rq_dispatched[0] = ctx->rq_dispatched[1] = 0;
return count;
}
static int ctx_merged_show(void *data, struct seq_file *m)
{
struct blk_mq_ctx *ctx = data;
seq_printf(m, "%lu\n", ctx->rq_merged);
return 0;
}
static ssize_t ctx_merged_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_ctx *ctx = data;
ctx->rq_merged = 0;
return count;
}
static int ctx_completed_show(void *data, struct seq_file *m)
{
struct blk_mq_ctx *ctx = data;
seq_printf(m, "%lu %lu\n", ctx->rq_completed[1], ctx->rq_completed[0]);
return 0;
}
static ssize_t ctx_completed_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_ctx *ctx = data;
ctx->rq_completed[0] = ctx->rq_completed[1] = 0;
return count;
}
static int blk_mq_debugfs_show(struct seq_file *m, void *v)
{
const struct blk_mq_debugfs_attr *attr = m->private;
void *data = d_inode(m->file->f_path.dentry->d_parent)->i_private;
return attr->show(data, m);
}
static ssize_t blk_mq_debugfs_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
const struct blk_mq_debugfs_attr *attr = m->private;
void *data = d_inode(file->f_path.dentry->d_parent)->i_private;
if (!attr->write)
return -EPERM;
return attr->write(data, buf, count, ppos);
}
static int blk_mq_debugfs_open(struct inode *inode, struct file *file)
{
const struct blk_mq_debugfs_attr *attr = inode->i_private;
void *data = d_inode(file->f_path.dentry->d_parent)->i_private;
struct seq_file *m;
int ret;
if (attr->seq_ops) {
ret = seq_open(file, attr->seq_ops);
if (!ret) {
m = file->private_data;
m->private = data;
}
return ret;
}
if (WARN_ON_ONCE(!attr->show))
return -EPERM;
return single_open(file, blk_mq_debugfs_show, inode->i_private);
}
static int blk_mq_debugfs_release(struct inode *inode, struct file *file)
{
const struct blk_mq_debugfs_attr *attr = inode->i_private;
if (attr->show)
return single_release(inode, file);
else
return seq_release(inode, file);
}
const struct file_operations blk_mq_debugfs_fops = {
.open = blk_mq_debugfs_open,
.read = seq_read,
.write = blk_mq_debugfs_write,
.llseek = seq_lseek,
.release = blk_mq_debugfs_release,
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_queue_attrs[] = {
{"poll_stat", 0400, queue_poll_stat_show},
{"requeue_list", 0400, .seq_ops = &queue_requeue_list_seq_ops},
{"state", 0600, queue_state_show, queue_state_write},
{"write_hints", 0600, queue_write_hint_show, queue_write_hint_store},
{},
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = {
{"state", 0400, hctx_state_show},
{"flags", 0400, hctx_flags_show},
{"dispatch", 0400, .seq_ops = &hctx_dispatch_seq_ops},
{"busy", 0400, hctx_busy_show},
{"ctx_map", 0400, hctx_ctx_map_show},
{"tags", 0400, hctx_tags_show},
{"tags_bitmap", 0400, hctx_tags_bitmap_show},
{"sched_tags", 0400, hctx_sched_tags_show},
{"sched_tags_bitmap", 0400, hctx_sched_tags_bitmap_show},
{"io_poll", 0600, hctx_io_poll_show, hctx_io_poll_write},
{"dispatched", 0600, hctx_dispatched_show, hctx_dispatched_write},
{"queued", 0600, hctx_queued_show, hctx_queued_write},
{"run", 0600, hctx_run_show, hctx_run_write},
{"active", 0400, hctx_active_show},
{},
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = {
{"rq_list", 0400, .seq_ops = &ctx_rq_list_seq_ops},
{"dispatched", 0600, ctx_dispatched_show, ctx_dispatched_write},
{"merged", 0600, ctx_merged_show, ctx_merged_write},
{"completed", 0600, ctx_completed_show, ctx_completed_write},
{},
};
static bool debugfs_create_files(struct dentry *parent, void *data,
const struct blk_mq_debugfs_attr *attr)
{
d_inode(parent)->i_private = data;
for (; attr->name; attr++) {
if (!debugfs_create_file(attr->name, attr->mode, parent,
(void *)attr, &blk_mq_debugfs_fops))
return false;
}
return true;
}
int blk_mq_debugfs_register(struct request_queue *q)
{
struct blk_mq_hw_ctx *hctx;
int i;
if (!blk_debugfs_root)
return -ENOENT;
q->debugfs_dir = debugfs_create_dir(kobject_name(q->kobj.parent),
blk_debugfs_root);
if (!q->debugfs_dir)
return -ENOMEM;
if (!debugfs_create_files(q->debugfs_dir, q,
blk_mq_debugfs_queue_attrs))
goto err;
/*
* blk_mq_init_hctx() attempted to do this already, but q->debugfs_dir
* didn't exist yet (because we don't know what to name the directory
* until the queue is registered to a gendisk).
*/
queue_for_each_hw_ctx(q, hctx, i) {
if (!hctx->debugfs_dir && blk_mq_debugfs_register_hctx(q, hctx))
goto err;
if (q->elevator && !hctx->sched_debugfs_dir &&
blk_mq_debugfs_register_sched_hctx(q, hctx))
goto err;
}
return 0;
err:
blk_mq_debugfs_unregister(q);
return -ENOMEM;
}
void blk_mq_debugfs_unregister(struct request_queue *q)
{
debugfs_remove_recursive(q->debugfs_dir);
q->sched_debugfs_dir = NULL;
q->debugfs_dir = NULL;
}
static int blk_mq_debugfs_register_ctx(struct blk_mq_hw_ctx *hctx,
struct blk_mq_ctx *ctx)
{
struct dentry *ctx_dir;
char name[20];
snprintf(name, sizeof(name), "cpu%u", ctx->cpu);
ctx_dir = debugfs_create_dir(name, hctx->debugfs_dir);
if (!ctx_dir)
return -ENOMEM;
if (!debugfs_create_files(ctx_dir, ctx, blk_mq_debugfs_ctx_attrs))
return -ENOMEM;
return 0;
}
int blk_mq_debugfs_register_hctx(struct request_queue *q,
struct blk_mq_hw_ctx *hctx)
{
struct blk_mq_ctx *ctx;
char name[20];
int i;
if (!q->debugfs_dir)
return -ENOENT;
snprintf(name, sizeof(name), "hctx%u", hctx->queue_num);
hctx->debugfs_dir = debugfs_create_dir(name, q->debugfs_dir);
if (!hctx->debugfs_dir)
return -ENOMEM;
if (!debugfs_create_files(hctx->debugfs_dir, hctx,
blk_mq_debugfs_hctx_attrs))
goto err;
hctx_for_each_ctx(hctx, ctx, i) {
if (blk_mq_debugfs_register_ctx(hctx, ctx))
goto err;
}
return 0;
err:
blk_mq_debugfs_unregister_hctx(hctx);
return -ENOMEM;
}
void blk_mq_debugfs_unregister_hctx(struct blk_mq_hw_ctx *hctx)
{
debugfs_remove_recursive(hctx->debugfs_dir);
hctx->sched_debugfs_dir = NULL;
hctx->debugfs_dir = NULL;
}
int blk_mq_debugfs_register_hctxs(struct request_queue *q)
{
struct blk_mq_hw_ctx *hctx;
int i;
queue_for_each_hw_ctx(q, hctx, i) {
if (blk_mq_debugfs_register_hctx(q, hctx))
return -ENOMEM;
}
return 0;
}
void blk_mq_debugfs_unregister_hctxs(struct request_queue *q)
{
struct blk_mq_hw_ctx *hctx;
int i;
queue_for_each_hw_ctx(q, hctx, i)
blk_mq_debugfs_unregister_hctx(hctx);
}
int blk_mq_debugfs_register_sched(struct request_queue *q)
{
struct elevator_type *e = q->elevator->type;
if (!q->debugfs_dir)
return -ENOENT;
if (!e->queue_debugfs_attrs)
return 0;
q->sched_debugfs_dir = debugfs_create_dir("sched", q->debugfs_dir);
if (!q->sched_debugfs_dir)
return -ENOMEM;
if (!debugfs_create_files(q->sched_debugfs_dir, q,
e->queue_debugfs_attrs))
goto err;
return 0;
err:
blk_mq_debugfs_unregister_sched(q);
return -ENOMEM;
}
void blk_mq_debugfs_unregister_sched(struct request_queue *q)
{
debugfs_remove_recursive(q->sched_debugfs_dir);
q->sched_debugfs_dir = NULL;
}
int blk_mq_debugfs_register_sched_hctx(struct request_queue *q,
struct blk_mq_hw_ctx *hctx)
{
struct elevator_type *e = q->elevator->type;
if (!hctx->debugfs_dir)
return -ENOENT;
if (!e->hctx_debugfs_attrs)
return 0;
hctx->sched_debugfs_dir = debugfs_create_dir("sched",
hctx->debugfs_dir);
if (!hctx->sched_debugfs_dir)
return -ENOMEM;
if (!debugfs_create_files(hctx->sched_debugfs_dir, hctx,
e->hctx_debugfs_attrs))
return -ENOMEM;
return 0;
}
void blk_mq_debugfs_unregister_sched_hctx(struct blk_mq_hw_ctx *hctx)
{
debugfs_remove_recursive(hctx->sched_debugfs_dir);
hctx->sched_debugfs_dir = NULL;
}
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