Merge branch 'blktrace' of git://brick.kernel.dk/data/git/linux-2.6-block
* 'blktrace' of git://brick.kernel.dk/data/git/linux-2.6-block: [PATCH] Block queue IO tracing support (blktrace) as of 2006-03-23 [PATCH] relay: consolidate sendfile() and read() code [PATCH] relay: add sendfile() support [PATCH] relay: migrate from relayfs to a generic relay API
This commit is contained in:
commit
cec6062037
@ -11,4 +11,16 @@ config LBD
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your machine, or if you want to have a raid or loopback device
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bigger than 2TB. Otherwise say N.
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config BLK_DEV_IO_TRACE
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bool "Support for tracing block io actions"
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select RELAY
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select DEBUG_FS
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help
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Say Y here, if you want to be able to trace the block layer actions
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on a given queue. Tracing allows you to see any traffic happening
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on a block device queue. For more information (and the user space
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support tools needed), fetch the blktrace app from:
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git://brick.kernel.dk/data/git/blktrace.git
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source block/Kconfig.iosched
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|
@ -8,3 +8,5 @@ obj-$(CONFIG_IOSCHED_NOOP) += noop-iosched.o
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obj-$(CONFIG_IOSCHED_AS) += as-iosched.o
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obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o
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obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o
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obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o
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|
538
block/blktrace.c
Normal file
538
block/blktrace.c
Normal file
@ -0,0 +1,538 @@
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/*
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* Copyright (C) 2006 Jens Axboe <axboe@suse.de>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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||||
* You should have received a copy of the GNU General Public License
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||||
* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*
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*/
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#include <linux/config.h>
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#include <linux/kernel.h>
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#include <linux/blkdev.h>
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#include <linux/blktrace_api.h>
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#include <linux/percpu.h>
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#include <linux/init.h>
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#include <linux/mutex.h>
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#include <linux/debugfs.h>
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#include <asm/uaccess.h>
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static DEFINE_PER_CPU(unsigned long long, blk_trace_cpu_offset) = { 0, };
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static unsigned int blktrace_seq __read_mostly = 1;
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/*
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* Send out a notify for this process, if we haven't done so since a trace
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* started
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*/
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static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk)
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{
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struct blk_io_trace *t;
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t = relay_reserve(bt->rchan, sizeof(*t) + sizeof(tsk->comm));
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if (t) {
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t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION;
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t->device = bt->dev;
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t->action = BLK_TC_ACT(BLK_TC_NOTIFY);
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t->pid = tsk->pid;
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t->cpu = smp_processor_id();
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t->pdu_len = sizeof(tsk->comm);
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memcpy((void *) t + sizeof(*t), tsk->comm, t->pdu_len);
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tsk->btrace_seq = blktrace_seq;
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}
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}
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static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector,
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pid_t pid)
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{
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if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0)
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return 1;
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if (sector < bt->start_lba || sector > bt->end_lba)
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return 1;
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if (bt->pid && pid != bt->pid)
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return 1;
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return 0;
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}
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/*
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* Data direction bit lookup
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*/
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static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK_TC_WRITE) };
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/*
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* Bio action bits of interest
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*/
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static u32 bio_act[3] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_ACT(BLK_TC_SYNC) };
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/*
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* More could be added as needed, taking care to increment the decrementer
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* to get correct indexing
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*/
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#define trace_barrier_bit(rw) \
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(((rw) & (1 << BIO_RW_BARRIER)) >> (BIO_RW_BARRIER - 0))
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#define trace_sync_bit(rw) \
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(((rw) & (1 << BIO_RW_SYNC)) >> (BIO_RW_SYNC - 1))
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/*
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* The worker for the various blk_add_trace*() types. Fills out a
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* blk_io_trace structure and places it in a per-cpu subbuffer.
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*/
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void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
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int rw, u32 what, int error, int pdu_len, void *pdu_data)
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{
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struct task_struct *tsk = current;
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struct blk_io_trace *t;
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unsigned long flags;
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unsigned long *sequence;
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pid_t pid;
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int cpu;
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if (unlikely(bt->trace_state != Blktrace_running))
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return;
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what |= ddir_act[rw & WRITE];
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what |= bio_act[trace_barrier_bit(rw)];
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what |= bio_act[trace_sync_bit(rw)];
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pid = tsk->pid;
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if (unlikely(act_log_check(bt, what, sector, pid)))
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return;
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/*
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* A word about the locking here - we disable interrupts to reserve
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* some space in the relay per-cpu buffer, to prevent an irq
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* from coming in and stepping on our toes. Once reserved, it's
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* enough to get preemption disabled to prevent read of this data
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* before we are through filling it. get_cpu()/put_cpu() does this
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* for us
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*/
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local_irq_save(flags);
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if (unlikely(tsk->btrace_seq != blktrace_seq))
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trace_note_tsk(bt, tsk);
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t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len);
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if (t) {
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cpu = smp_processor_id();
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sequence = per_cpu_ptr(bt->sequence, cpu);
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t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION;
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t->sequence = ++(*sequence);
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t->time = sched_clock() - per_cpu(blk_trace_cpu_offset, cpu);
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t->sector = sector;
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t->bytes = bytes;
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t->action = what;
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t->pid = pid;
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t->device = bt->dev;
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t->cpu = cpu;
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t->error = error;
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t->pdu_len = pdu_len;
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if (pdu_len)
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memcpy((void *) t + sizeof(*t), pdu_data, pdu_len);
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}
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local_irq_restore(flags);
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}
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EXPORT_SYMBOL_GPL(__blk_add_trace);
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static struct dentry *blk_tree_root;
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static struct mutex blk_tree_mutex;
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static unsigned int root_users;
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static inline void blk_remove_root(void)
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||||
{
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||||
if (blk_tree_root) {
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||||
debugfs_remove(blk_tree_root);
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blk_tree_root = NULL;
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||||
}
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||||
}
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||||
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||||
static void blk_remove_tree(struct dentry *dir)
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||||
{
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mutex_lock(&blk_tree_mutex);
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debugfs_remove(dir);
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||||
if (--root_users == 0)
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blk_remove_root();
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mutex_unlock(&blk_tree_mutex);
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}
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static struct dentry *blk_create_tree(const char *blk_name)
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{
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struct dentry *dir = NULL;
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||||
mutex_lock(&blk_tree_mutex);
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if (!blk_tree_root) {
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blk_tree_root = debugfs_create_dir("block", NULL);
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||||
if (!blk_tree_root)
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goto err;
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||||
}
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dir = debugfs_create_dir(blk_name, blk_tree_root);
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if (dir)
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root_users++;
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else
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blk_remove_root();
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err:
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mutex_unlock(&blk_tree_mutex);
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return dir;
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}
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static void blk_trace_cleanup(struct blk_trace *bt)
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{
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relay_close(bt->rchan);
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debugfs_remove(bt->dropped_file);
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blk_remove_tree(bt->dir);
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free_percpu(bt->sequence);
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kfree(bt);
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}
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static int blk_trace_remove(request_queue_t *q)
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{
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struct blk_trace *bt;
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bt = xchg(&q->blk_trace, NULL);
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if (!bt)
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return -EINVAL;
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if (bt->trace_state == Blktrace_setup ||
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bt->trace_state == Blktrace_stopped)
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blk_trace_cleanup(bt);
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return 0;
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}
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static int blk_dropped_open(struct inode *inode, struct file *filp)
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{
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filp->private_data = inode->u.generic_ip;
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return 0;
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}
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static ssize_t blk_dropped_read(struct file *filp, char __user *buffer,
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size_t count, loff_t *ppos)
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{
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struct blk_trace *bt = filp->private_data;
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char buf[16];
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snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped));
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return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf));
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}
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static struct file_operations blk_dropped_fops = {
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||||
.owner = THIS_MODULE,
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.open = blk_dropped_open,
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.read = blk_dropped_read,
|
||||
};
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||||
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||||
/*
|
||||
* Keep track of how many times we encountered a full subbuffer, to aid
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* the user space app in telling how many lost events there were.
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||||
*/
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||||
static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf,
|
||||
void *prev_subbuf, size_t prev_padding)
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||||
{
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||||
struct blk_trace *bt;
|
||||
|
||||
if (!relay_buf_full(buf))
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||||
return 1;
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||||
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||||
bt = buf->chan->private_data;
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||||
atomic_inc(&bt->dropped);
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||||
return 0;
|
||||
}
|
||||
|
||||
static int blk_remove_buf_file_callback(struct dentry *dentry)
|
||||
{
|
||||
debugfs_remove(dentry);
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||||
return 0;
|
||||
}
|
||||
|
||||
static struct dentry *blk_create_buf_file_callback(const char *filename,
|
||||
struct dentry *parent,
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||||
int mode,
|
||||
struct rchan_buf *buf,
|
||||
int *is_global)
|
||||
{
|
||||
return debugfs_create_file(filename, mode, parent, buf,
|
||||
&relay_file_operations);
|
||||
}
|
||||
|
||||
static struct rchan_callbacks blk_relay_callbacks = {
|
||||
.subbuf_start = blk_subbuf_start_callback,
|
||||
.create_buf_file = blk_create_buf_file_callback,
|
||||
.remove_buf_file = blk_remove_buf_file_callback,
|
||||
};
|
||||
|
||||
/*
|
||||
* Setup everything required to start tracing
|
||||
*/
|
||||
static int blk_trace_setup(request_queue_t *q, struct block_device *bdev,
|
||||
char __user *arg)
|
||||
{
|
||||
struct blk_user_trace_setup buts;
|
||||
struct blk_trace *old_bt, *bt = NULL;
|
||||
struct dentry *dir = NULL;
|
||||
char b[BDEVNAME_SIZE];
|
||||
int ret, i;
|
||||
|
||||
if (copy_from_user(&buts, arg, sizeof(buts)))
|
||||
return -EFAULT;
|
||||
|
||||
if (!buts.buf_size || !buts.buf_nr)
|
||||
return -EINVAL;
|
||||
|
||||
strcpy(buts.name, bdevname(bdev, b));
|
||||
|
||||
/*
|
||||
* some device names have larger paths - convert the slashes
|
||||
* to underscores for this to work as expected
|
||||
*/
|
||||
for (i = 0; i < strlen(buts.name); i++)
|
||||
if (buts.name[i] == '/')
|
||||
buts.name[i] = '_';
|
||||
|
||||
if (copy_to_user(arg, &buts, sizeof(buts)))
|
||||
return -EFAULT;
|
||||
|
||||
ret = -ENOMEM;
|
||||
bt = kzalloc(sizeof(*bt), GFP_KERNEL);
|
||||
if (!bt)
|
||||
goto err;
|
||||
|
||||
bt->sequence = alloc_percpu(unsigned long);
|
||||
if (!bt->sequence)
|
||||
goto err;
|
||||
|
||||
ret = -ENOENT;
|
||||
dir = blk_create_tree(buts.name);
|
||||
if (!dir)
|
||||
goto err;
|
||||
|
||||
bt->dir = dir;
|
||||
bt->dev = bdev->bd_dev;
|
||||
atomic_set(&bt->dropped, 0);
|
||||
|
||||
ret = -EIO;
|
||||
bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, &blk_dropped_fops);
|
||||
if (!bt->dropped_file)
|
||||
goto err;
|
||||
|
||||
bt->rchan = relay_open("trace", dir, buts.buf_size, buts.buf_nr, &blk_relay_callbacks);
|
||||
if (!bt->rchan)
|
||||
goto err;
|
||||
bt->rchan->private_data = bt;
|
||||
|
||||
bt->act_mask = buts.act_mask;
|
||||
if (!bt->act_mask)
|
||||
bt->act_mask = (u16) -1;
|
||||
|
||||
bt->start_lba = buts.start_lba;
|
||||
bt->end_lba = buts.end_lba;
|
||||
if (!bt->end_lba)
|
||||
bt->end_lba = -1ULL;
|
||||
|
||||
bt->pid = buts.pid;
|
||||
bt->trace_state = Blktrace_setup;
|
||||
|
||||
ret = -EBUSY;
|
||||
old_bt = xchg(&q->blk_trace, bt);
|
||||
if (old_bt) {
|
||||
(void) xchg(&q->blk_trace, old_bt);
|
||||
goto err;
|
||||
}
|
||||
|
||||
return 0;
|
||||
err:
|
||||
if (dir)
|
||||
blk_remove_tree(dir);
|
||||
if (bt) {
|
||||
if (bt->dropped_file)
|
||||
debugfs_remove(bt->dropped_file);
|
||||
if (bt->sequence)
|
||||
free_percpu(bt->sequence);
|
||||
if (bt->rchan)
|
||||
relay_close(bt->rchan);
|
||||
kfree(bt);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int blk_trace_startstop(request_queue_t *q, int start)
|
||||
{
|
||||
struct blk_trace *bt;
|
||||
int ret;
|
||||
|
||||
if ((bt = q->blk_trace) == NULL)
|
||||
return -EINVAL;
|
||||
|
||||
/*
|
||||
* For starting a trace, we can transition from a setup or stopped
|
||||
* trace. For stopping a trace, the state must be running
|
||||
*/
|
||||
ret = -EINVAL;
|
||||
if (start) {
|
||||
if (bt->trace_state == Blktrace_setup ||
|
||||
bt->trace_state == Blktrace_stopped) {
|
||||
blktrace_seq++;
|
||||
smp_mb();
|
||||
bt->trace_state = Blktrace_running;
|
||||
ret = 0;
|
||||
}
|
||||
} else {
|
||||
if (bt->trace_state == Blktrace_running) {
|
||||
bt->trace_state = Blktrace_stopped;
|
||||
relay_flush(bt->rchan);
|
||||
ret = 0;
|
||||
}
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* blk_trace_ioctl: - handle the ioctls associated with tracing
|
||||
* @bdev: the block device
|
||||
* @cmd: the ioctl cmd
|
||||
* @arg: the argument data, if any
|
||||
*
|
||||
**/
|
||||
int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
|
||||
{
|
||||
request_queue_t *q;
|
||||
int ret, start = 0;
|
||||
|
||||
q = bdev_get_queue(bdev);
|
||||
if (!q)
|
||||
return -ENXIO;
|
||||
|
||||
mutex_lock(&bdev->bd_mutex);
|
||||
|
||||
switch (cmd) {
|
||||
case BLKTRACESETUP:
|
||||
ret = blk_trace_setup(q, bdev, arg);
|
||||
break;
|
||||
case BLKTRACESTART:
|
||||
start = 1;
|
||||
case BLKTRACESTOP:
|
||||
ret = blk_trace_startstop(q, start);
|
||||
break;
|
||||
case BLKTRACETEARDOWN:
|
||||
ret = blk_trace_remove(q);
|
||||
break;
|
||||
default:
|
||||
ret = -ENOTTY;
|
||||
break;
|
||||
}
|
||||
|
||||
mutex_unlock(&bdev->bd_mutex);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* blk_trace_shutdown: - stop and cleanup trace structures
|
||||
* @q: the request queue associated with the device
|
||||
*
|
||||
**/
|
||||
void blk_trace_shutdown(request_queue_t *q)
|
||||
{
|
||||
blk_trace_startstop(q, 0);
|
||||
blk_trace_remove(q);
|
||||
}
|
||||
|
||||
/*
|
||||
* Average offset over two calls to sched_clock() with a gettimeofday()
|
||||
* in the middle
|
||||
*/
|
||||
static void blk_check_time(unsigned long long *t)
|
||||
{
|
||||
unsigned long long a, b;
|
||||
struct timeval tv;
|
||||
|
||||
a = sched_clock();
|
||||
do_gettimeofday(&tv);
|
||||
b = sched_clock();
|
||||
|
||||
*t = tv.tv_sec * 1000000000 + tv.tv_usec * 1000;
|
||||
*t -= (a + b) / 2;
|
||||
}
|
||||
|
||||
static void blk_trace_check_cpu_time(void *data)
|
||||
{
|
||||
unsigned long long *t;
|
||||
int cpu = get_cpu();
|
||||
|
||||
t = &per_cpu(blk_trace_cpu_offset, cpu);
|
||||
|
||||
/*
|
||||
* Just call it twice, hopefully the second call will be cache hot
|
||||
* and a little more precise
|
||||
*/
|
||||
blk_check_time(t);
|
||||
blk_check_time(t);
|
||||
|
||||
put_cpu();
|
||||
}
|
||||
|
||||
/*
|
||||
* Call blk_trace_check_cpu_time() on each CPU to calibrate our inter-CPU
|
||||
* timings
|
||||
*/
|
||||
static void blk_trace_calibrate_offsets(void)
|
||||
{
|
||||
unsigned long flags;
|
||||
|
||||
smp_call_function(blk_trace_check_cpu_time, NULL, 1, 1);
|
||||
local_irq_save(flags);
|
||||
blk_trace_check_cpu_time(NULL);
|
||||
local_irq_restore(flags);
|
||||
}
|
||||
|
||||
static void blk_trace_set_ht_offsets(void)
|
||||
{
|
||||
#if defined(CONFIG_SCHED_SMT)
|
||||
int cpu, i;
|
||||
|
||||
/*
|
||||
* now make sure HT siblings have the same time offset
|
||||
*/
|
||||
preempt_disable();
|
||||
for_each_online_cpu(cpu) {
|
||||
unsigned long long *cpu_off, *sibling_off;
|
||||
|
||||
for_each_cpu_mask(i, cpu_sibling_map[cpu]) {
|
||||
if (i == cpu)
|
||||
continue;
|
||||
|
||||
cpu_off = &per_cpu(blk_trace_cpu_offset, cpu);
|
||||
sibling_off = &per_cpu(blk_trace_cpu_offset, i);
|
||||
*sibling_off = *cpu_off;
|
||||
}
|
||||
}
|
||||
preempt_enable();
|
||||
#endif
|
||||
}
|
||||
|
||||
static __init int blk_trace_init(void)
|
||||
{
|
||||
mutex_init(&blk_tree_mutex);
|
||||
blk_trace_calibrate_offsets();
|
||||
blk_trace_set_ht_offsets();
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
module_init(blk_trace_init);
|
||||
|
@ -33,6 +33,7 @@
|
||||
#include <linux/init.h>
|
||||
#include <linux/compiler.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/blktrace_api.h>
|
||||
|
||||
#include <asm/uaccess.h>
|
||||
|
||||
@ -333,6 +334,8 @@ void elv_insert(request_queue_t *q, struct request *rq, int where)
|
||||
struct list_head *pos;
|
||||
unsigned ordseq;
|
||||
|
||||
blk_add_trace_rq(q, rq, BLK_TA_INSERT);
|
||||
|
||||
rq->q = q;
|
||||
|
||||
switch (where) {
|
||||
@ -499,6 +502,7 @@ struct request *elv_next_request(request_queue_t *q)
|
||||
* not be passed by new incoming requests
|
||||
*/
|
||||
rq->flags |= REQ_STARTED;
|
||||
blk_add_trace_rq(q, rq, BLK_TA_ISSUE);
|
||||
}
|
||||
|
||||
if (!q->boundary_rq || q->boundary_rq == rq) {
|
||||
|
@ -5,6 +5,7 @@
|
||||
#include <linux/backing-dev.h>
|
||||
#include <linux/buffer_head.h>
|
||||
#include <linux/smp_lock.h>
|
||||
#include <linux/blktrace_api.h>
|
||||
#include <asm/uaccess.h>
|
||||
|
||||
static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
|
||||
@ -189,6 +190,11 @@ static int blkdev_locked_ioctl(struct file *file, struct block_device *bdev,
|
||||
return put_ulong(arg, bdev->bd_inode->i_size >> 9);
|
||||
case BLKGETSIZE64:
|
||||
return put_u64(arg, bdev->bd_inode->i_size);
|
||||
case BLKTRACESTART:
|
||||
case BLKTRACESTOP:
|
||||
case BLKTRACESETUP:
|
||||
case BLKTRACETEARDOWN:
|
||||
return blk_trace_ioctl(bdev, cmd, (char __user *) arg);
|
||||
}
|
||||
return -ENOIOCTLCMD;
|
||||
}
|
||||
|
@ -28,6 +28,7 @@
|
||||
#include <linux/writeback.h>
|
||||
#include <linux/interrupt.h>
|
||||
#include <linux/cpu.h>
|
||||
#include <linux/blktrace_api.h>
|
||||
|
||||
/*
|
||||
* for max sense size
|
||||
@ -1556,8 +1557,10 @@ void blk_plug_device(request_queue_t *q)
|
||||
if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags))
|
||||
return;
|
||||
|
||||
if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags))
|
||||
if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) {
|
||||
mod_timer(&q->unplug_timer, jiffies + q->unplug_delay);
|
||||
blk_add_trace_generic(q, NULL, 0, BLK_TA_PLUG);
|
||||
}
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(blk_plug_device);
|
||||
@ -1621,14 +1624,21 @@ static void blk_backing_dev_unplug(struct backing_dev_info *bdi,
|
||||
/*
|
||||
* devices don't necessarily have an ->unplug_fn defined
|
||||
*/
|
||||
if (q->unplug_fn)
|
||||
if (q->unplug_fn) {
|
||||
blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL,
|
||||
q->rq.count[READ] + q->rq.count[WRITE]);
|
||||
|
||||
q->unplug_fn(q);
|
||||
}
|
||||
}
|
||||
|
||||
static void blk_unplug_work(void *data)
|
||||
{
|
||||
request_queue_t *q = data;
|
||||
|
||||
blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL,
|
||||
q->rq.count[READ] + q->rq.count[WRITE]);
|
||||
|
||||
q->unplug_fn(q);
|
||||
}
|
||||
|
||||
@ -1636,6 +1646,9 @@ static void blk_unplug_timeout(unsigned long data)
|
||||
{
|
||||
request_queue_t *q = (request_queue_t *)data;
|
||||
|
||||
blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_TIMER, NULL,
|
||||
q->rq.count[READ] + q->rq.count[WRITE]);
|
||||
|
||||
kblockd_schedule_work(&q->unplug_work);
|
||||
}
|
||||
|
||||
@ -1753,6 +1766,9 @@ static void blk_release_queue(struct kobject *kobj)
|
||||
if (q->queue_tags)
|
||||
__blk_queue_free_tags(q);
|
||||
|
||||
if (q->blk_trace)
|
||||
blk_trace_shutdown(q);
|
||||
|
||||
kmem_cache_free(requestq_cachep, q);
|
||||
}
|
||||
|
||||
@ -2129,6 +2145,8 @@ static struct request *get_request(request_queue_t *q, int rw, struct bio *bio,
|
||||
|
||||
rq_init(q, rq);
|
||||
rq->rl = rl;
|
||||
|
||||
blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ);
|
||||
out:
|
||||
return rq;
|
||||
}
|
||||
@ -2157,6 +2175,8 @@ static struct request *get_request_wait(request_queue_t *q, int rw,
|
||||
if (!rq) {
|
||||
struct io_context *ioc;
|
||||
|
||||
blk_add_trace_generic(q, bio, rw, BLK_TA_SLEEPRQ);
|
||||
|
||||
__generic_unplug_device(q);
|
||||
spin_unlock_irq(q->queue_lock);
|
||||
io_schedule();
|
||||
@ -2210,6 +2230,8 @@ EXPORT_SYMBOL(blk_get_request);
|
||||
*/
|
||||
void blk_requeue_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
blk_add_trace_rq(q, rq, BLK_TA_REQUEUE);
|
||||
|
||||
if (blk_rq_tagged(rq))
|
||||
blk_queue_end_tag(q, rq);
|
||||
|
||||
@ -2844,6 +2866,8 @@ static int __make_request(request_queue_t *q, struct bio *bio)
|
||||
if (!q->back_merge_fn(q, req, bio))
|
||||
break;
|
||||
|
||||
blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE);
|
||||
|
||||
req->biotail->bi_next = bio;
|
||||
req->biotail = bio;
|
||||
req->nr_sectors = req->hard_nr_sectors += nr_sectors;
|
||||
@ -2859,6 +2883,8 @@ static int __make_request(request_queue_t *q, struct bio *bio)
|
||||
if (!q->front_merge_fn(q, req, bio))
|
||||
break;
|
||||
|
||||
blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE);
|
||||
|
||||
bio->bi_next = req->bio;
|
||||
req->bio = bio;
|
||||
|
||||
@ -2976,6 +3002,7 @@ void generic_make_request(struct bio *bio)
|
||||
request_queue_t *q;
|
||||
sector_t maxsector;
|
||||
int ret, nr_sectors = bio_sectors(bio);
|
||||
dev_t old_dev;
|
||||
|
||||
might_sleep();
|
||||
/* Test device or partition size, when known. */
|
||||
@ -3002,6 +3029,8 @@ void generic_make_request(struct bio *bio)
|
||||
* NOTE: we don't repeat the blk_size check for each new device.
|
||||
* Stacking drivers are expected to know what they are doing.
|
||||
*/
|
||||
maxsector = -1;
|
||||
old_dev = 0;
|
||||
do {
|
||||
char b[BDEVNAME_SIZE];
|
||||
|
||||
@ -3034,6 +3063,15 @@ void generic_make_request(struct bio *bio)
|
||||
*/
|
||||
blk_partition_remap(bio);
|
||||
|
||||
if (maxsector != -1)
|
||||
blk_add_trace_remap(q, bio, old_dev, bio->bi_sector,
|
||||
maxsector);
|
||||
|
||||
blk_add_trace_bio(q, bio, BLK_TA_QUEUE);
|
||||
|
||||
maxsector = bio->bi_sector;
|
||||
old_dev = bio->bi_bdev->bd_dev;
|
||||
|
||||
ret = q->make_request_fn(q, bio);
|
||||
} while (ret);
|
||||
}
|
||||
@ -3153,6 +3191,8 @@ static int __end_that_request_first(struct request *req, int uptodate,
|
||||
int total_bytes, bio_nbytes, error, next_idx = 0;
|
||||
struct bio *bio;
|
||||
|
||||
blk_add_trace_rq(req->q, req, BLK_TA_COMPLETE);
|
||||
|
||||
/*
|
||||
* extend uptodate bool to allow < 0 value to be direct io error
|
||||
*/
|
||||
|
@ -38,6 +38,7 @@
|
||||
#include <linux/hdreg.h>
|
||||
#include <linux/spinlock.h>
|
||||
#include <linux/compat.h>
|
||||
#include <linux/blktrace_api.h>
|
||||
#include <asm/uaccess.h>
|
||||
#include <asm/io.h>
|
||||
|
||||
@ -2331,6 +2332,7 @@ static inline void complete_command( ctlr_info_t *h, CommandList_struct *cmd,
|
||||
|
||||
cmd->rq->completion_data = cmd;
|
||||
cmd->rq->errors = status;
|
||||
blk_add_trace_rq(cmd->rq->q, cmd->rq, BLK_TA_COMPLETE);
|
||||
blk_complete_request(cmd->rq);
|
||||
}
|
||||
|
||||
|
@ -17,6 +17,7 @@
|
||||
#include <linux/mempool.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/idr.h>
|
||||
#include <linux/blktrace_api.h>
|
||||
|
||||
static const char *_name = DM_NAME;
|
||||
|
||||
@ -334,6 +335,8 @@ static void dec_pending(struct dm_io *io, int error)
|
||||
/* nudge anyone waiting on suspend queue */
|
||||
wake_up(&io->md->wait);
|
||||
|
||||
blk_add_trace_bio(io->md->queue, io->bio, BLK_TA_COMPLETE);
|
||||
|
||||
bio_endio(io->bio, io->bio->bi_size, io->error);
|
||||
free_io(io->md, io);
|
||||
}
|
||||
@ -392,6 +395,7 @@ static void __map_bio(struct dm_target *ti, struct bio *clone,
|
||||
struct target_io *tio)
|
||||
{
|
||||
int r;
|
||||
sector_t sector;
|
||||
|
||||
/*
|
||||
* Sanity checks.
|
||||
@ -407,10 +411,17 @@ static void __map_bio(struct dm_target *ti, struct bio *clone,
|
||||
* this io.
|
||||
*/
|
||||
atomic_inc(&tio->io->io_count);
|
||||
sector = clone->bi_sector;
|
||||
r = ti->type->map(ti, clone, &tio->info);
|
||||
if (r > 0)
|
||||
if (r > 0) {
|
||||
/* the bio has been remapped so dispatch it */
|
||||
|
||||
blk_add_trace_remap(bdev_get_queue(clone->bi_bdev), clone,
|
||||
tio->io->bio->bi_bdev->bd_dev, sector,
|
||||
clone->bi_sector);
|
||||
|
||||
generic_make_request(clone);
|
||||
}
|
||||
|
||||
else if (r < 0) {
|
||||
/* error the io and bail out */
|
||||
|
12
fs/Kconfig
12
fs/Kconfig
@ -859,18 +859,6 @@ config RAMFS
|
||||
To compile this as a module, choose M here: the module will be called
|
||||
ramfs.
|
||||
|
||||
config RELAYFS_FS
|
||||
tristate "Relayfs file system support"
|
||||
---help---
|
||||
Relayfs is a high-speed data relay filesystem designed to provide
|
||||
an efficient mechanism for tools and facilities to relay large
|
||||
amounts of data from kernel space to user space.
|
||||
|
||||
To compile this code as a module, choose M here: the module will be
|
||||
called relayfs.
|
||||
|
||||
If unsure, say N.
|
||||
|
||||
config CONFIGFS_FS
|
||||
tristate "Userspace-driven configuration filesystem (EXPERIMENTAL)"
|
||||
depends on EXPERIMENTAL
|
||||
|
@ -91,7 +91,6 @@ obj-$(CONFIG_AUTOFS4_FS) += autofs4/
|
||||
obj-$(CONFIG_ADFS_FS) += adfs/
|
||||
obj-$(CONFIG_FUSE_FS) += fuse/
|
||||
obj-$(CONFIG_UDF_FS) += udf/
|
||||
obj-$(CONFIG_RELAYFS_FS) += relayfs/
|
||||
obj-$(CONFIG_SUN_OPENPROMFS) += openpromfs/
|
||||
obj-$(CONFIG_JFS_FS) += jfs/
|
||||
obj-$(CONFIG_XFS_FS) += xfs/
|
||||
|
4
fs/bio.c
4
fs/bio.c
@ -25,6 +25,7 @@
|
||||
#include <linux/module.h>
|
||||
#include <linux/mempool.h>
|
||||
#include <linux/workqueue.h>
|
||||
#include <linux/blktrace_api.h>
|
||||
#include <scsi/sg.h> /* for struct sg_iovec */
|
||||
|
||||
#define BIO_POOL_SIZE 256
|
||||
@ -1095,6 +1096,9 @@ struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors)
|
||||
if (!bp)
|
||||
return bp;
|
||||
|
||||
blk_add_trace_pdu_int(bdev_get_queue(bi->bi_bdev), BLK_TA_SPLIT, bi,
|
||||
bi->bi_sector + first_sectors);
|
||||
|
||||
BUG_ON(bi->bi_vcnt != 1);
|
||||
BUG_ON(bi->bi_idx != 0);
|
||||
atomic_set(&bp->cnt, 3);
|
||||
|
@ -72,6 +72,7 @@
|
||||
#include <linux/i2c-dev.h>
|
||||
#include <linux/wireless.h>
|
||||
#include <linux/atalk.h>
|
||||
#include <linux/blktrace_api.h>
|
||||
|
||||
#include <net/sock.h> /* siocdevprivate_ioctl */
|
||||
#include <net/bluetooth/bluetooth.h>
|
||||
|
@ -1,4 +0,0 @@
|
||||
obj-$(CONFIG_RELAYFS_FS) += relayfs.o
|
||||
|
||||
relayfs-y := relay.o inode.o buffers.o
|
||||
|
@ -1,190 +0,0 @@
|
||||
/*
|
||||
* RelayFS buffer management code.
|
||||
*
|
||||
* Copyright (C) 2002-2005 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp
|
||||
* Copyright (C) 1999-2005 - Karim Yaghmour (karim@opersys.com)
|
||||
*
|
||||
* This file is released under the GPL.
|
||||
*/
|
||||
|
||||
#include <linux/module.h>
|
||||
#include <linux/vmalloc.h>
|
||||
#include <linux/mm.h>
|
||||
#include <linux/relayfs_fs.h>
|
||||
#include "relay.h"
|
||||
#include "buffers.h"
|
||||
|
||||
/*
|
||||
* close() vm_op implementation for relayfs file mapping.
|
||||
*/
|
||||
static void relay_file_mmap_close(struct vm_area_struct *vma)
|
||||
{
|
||||
struct rchan_buf *buf = vma->vm_private_data;
|
||||
buf->chan->cb->buf_unmapped(buf, vma->vm_file);
|
||||
}
|
||||
|
||||
/*
|
||||
* nopage() vm_op implementation for relayfs file mapping.
|
||||
*/
|
||||
static struct page *relay_buf_nopage(struct vm_area_struct *vma,
|
||||
unsigned long address,
|
||||
int *type)
|
||||
{
|
||||
struct page *page;
|
||||
struct rchan_buf *buf = vma->vm_private_data;
|
||||
unsigned long offset = address - vma->vm_start;
|
||||
|
||||
if (address > vma->vm_end)
|
||||
return NOPAGE_SIGBUS; /* Disallow mremap */
|
||||
if (!buf)
|
||||
return NOPAGE_OOM;
|
||||
|
||||
page = vmalloc_to_page(buf->start + offset);
|
||||
if (!page)
|
||||
return NOPAGE_OOM;
|
||||
get_page(page);
|
||||
|
||||
if (type)
|
||||
*type = VM_FAULT_MINOR;
|
||||
|
||||
return page;
|
||||
}
|
||||
|
||||
/*
|
||||
* vm_ops for relay file mappings.
|
||||
*/
|
||||
static struct vm_operations_struct relay_file_mmap_ops = {
|
||||
.nopage = relay_buf_nopage,
|
||||
.close = relay_file_mmap_close,
|
||||
};
|
||||
|
||||
/**
|
||||
* relay_mmap_buf: - mmap channel buffer to process address space
|
||||
* @buf: relay channel buffer
|
||||
* @vma: vm_area_struct describing memory to be mapped
|
||||
*
|
||||
* Returns 0 if ok, negative on error
|
||||
*
|
||||
* Caller should already have grabbed mmap_sem.
|
||||
*/
|
||||
int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma)
|
||||
{
|
||||
unsigned long length = vma->vm_end - vma->vm_start;
|
||||
struct file *filp = vma->vm_file;
|
||||
|
||||
if (!buf)
|
||||
return -EBADF;
|
||||
|
||||
if (length != (unsigned long)buf->chan->alloc_size)
|
||||
return -EINVAL;
|
||||
|
||||
vma->vm_ops = &relay_file_mmap_ops;
|
||||
vma->vm_private_data = buf;
|
||||
buf->chan->cb->buf_mapped(buf, filp);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_alloc_buf - allocate a channel buffer
|
||||
* @buf: the buffer struct
|
||||
* @size: total size of the buffer
|
||||
*
|
||||
* Returns a pointer to the resulting buffer, NULL if unsuccessful
|
||||
*/
|
||||
static void *relay_alloc_buf(struct rchan_buf *buf, unsigned long size)
|
||||
{
|
||||
void *mem;
|
||||
unsigned int i, j, n_pages;
|
||||
|
||||
size = PAGE_ALIGN(size);
|
||||
n_pages = size >> PAGE_SHIFT;
|
||||
|
||||
buf->page_array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL);
|
||||
if (!buf->page_array)
|
||||
return NULL;
|
||||
|
||||
for (i = 0; i < n_pages; i++) {
|
||||
buf->page_array[i] = alloc_page(GFP_KERNEL);
|
||||
if (unlikely(!buf->page_array[i]))
|
||||
goto depopulate;
|
||||
}
|
||||
mem = vmap(buf->page_array, n_pages, VM_MAP, PAGE_KERNEL);
|
||||
if (!mem)
|
||||
goto depopulate;
|
||||
|
||||
memset(mem, 0, size);
|
||||
buf->page_count = n_pages;
|
||||
return mem;
|
||||
|
||||
depopulate:
|
||||
for (j = 0; j < i; j++)
|
||||
__free_page(buf->page_array[j]);
|
||||
kfree(buf->page_array);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_create_buf - allocate and initialize a channel buffer
|
||||
* @alloc_size: size of the buffer to allocate
|
||||
* @n_subbufs: number of sub-buffers in the channel
|
||||
*
|
||||
* Returns channel buffer if successful, NULL otherwise
|
||||
*/
|
||||
struct rchan_buf *relay_create_buf(struct rchan *chan)
|
||||
{
|
||||
struct rchan_buf *buf = kcalloc(1, sizeof(struct rchan_buf), GFP_KERNEL);
|
||||
if (!buf)
|
||||
return NULL;
|
||||
|
||||
buf->padding = kmalloc(chan->n_subbufs * sizeof(size_t *), GFP_KERNEL);
|
||||
if (!buf->padding)
|
||||
goto free_buf;
|
||||
|
||||
buf->start = relay_alloc_buf(buf, chan->alloc_size);
|
||||
if (!buf->start)
|
||||
goto free_buf;
|
||||
|
||||
buf->chan = chan;
|
||||
kref_get(&buf->chan->kref);
|
||||
return buf;
|
||||
|
||||
free_buf:
|
||||
kfree(buf->padding);
|
||||
kfree(buf);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_destroy_buf - destroy an rchan_buf struct and associated buffer
|
||||
* @buf: the buffer struct
|
||||
*/
|
||||
void relay_destroy_buf(struct rchan_buf *buf)
|
||||
{
|
||||
struct rchan *chan = buf->chan;
|
||||
unsigned int i;
|
||||
|
||||
if (likely(buf->start)) {
|
||||
vunmap(buf->start);
|
||||
for (i = 0; i < buf->page_count; i++)
|
||||
__free_page(buf->page_array[i]);
|
||||
kfree(buf->page_array);
|
||||
}
|
||||
kfree(buf->padding);
|
||||
kfree(buf);
|
||||
kref_put(&chan->kref, relay_destroy_channel);
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_remove_buf - remove a channel buffer
|
||||
*
|
||||
* Removes the file from the relayfs fileystem, which also frees the
|
||||
* rchan_buf_struct and the channel buffer. Should only be called from
|
||||
* kref_put().
|
||||
*/
|
||||
void relay_remove_buf(struct kref *kref)
|
||||
{
|
||||
struct rchan_buf *buf = container_of(kref, struct rchan_buf, kref);
|
||||
buf->chan->cb->remove_buf_file(buf->dentry);
|
||||
relay_destroy_buf(buf);
|
||||
}
|
@ -1,12 +0,0 @@
|
||||
#ifndef _BUFFERS_H
|
||||
#define _BUFFERS_H
|
||||
|
||||
/* This inspired by rtai/shmem */
|
||||
#define FIX_SIZE(x) (((x) - 1) & PAGE_MASK) + PAGE_SIZE
|
||||
|
||||
extern int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma);
|
||||
extern struct rchan_buf *relay_create_buf(struct rchan *chan);
|
||||
extern void relay_destroy_buf(struct rchan_buf *buf);
|
||||
extern void relay_remove_buf(struct kref *kref);
|
||||
|
||||
#endif/* _BUFFERS_H */
|
@ -1,581 +0,0 @@
|
||||
/*
|
||||
* VFS-related code for RelayFS, a high-speed data relay filesystem.
|
||||
*
|
||||
* Copyright (C) 2003-2005 - Tom Zanussi <zanussi@us.ibm.com>, IBM Corp
|
||||
* Copyright (C) 2003-2005 - Karim Yaghmour <karim@opersys.com>
|
||||
*
|
||||
* Based on ramfs, Copyright (C) 2002 - Linus Torvalds
|
||||
*
|
||||
* This file is released under the GPL.
|
||||
*/
|
||||
|
||||
#include <linux/module.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/mount.h>
|
||||
#include <linux/pagemap.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/string.h>
|
||||
#include <linux/backing-dev.h>
|
||||
#include <linux/namei.h>
|
||||
#include <linux/poll.h>
|
||||
#include <linux/relayfs_fs.h>
|
||||
#include "relay.h"
|
||||
#include "buffers.h"
|
||||
|
||||
#define RELAYFS_MAGIC 0xF0B4A981
|
||||
|
||||
static struct vfsmount * relayfs_mount;
|
||||
static int relayfs_mount_count;
|
||||
|
||||
static struct backing_dev_info relayfs_backing_dev_info = {
|
||||
.ra_pages = 0, /* No readahead */
|
||||
.capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK,
|
||||
};
|
||||
|
||||
static struct inode *relayfs_get_inode(struct super_block *sb,
|
||||
int mode,
|
||||
struct file_operations *fops,
|
||||
void *data)
|
||||
{
|
||||
struct inode *inode;
|
||||
|
||||
inode = new_inode(sb);
|
||||
if (!inode)
|
||||
return NULL;
|
||||
|
||||
inode->i_mode = mode;
|
||||
inode->i_uid = 0;
|
||||
inode->i_gid = 0;
|
||||
inode->i_blksize = PAGE_CACHE_SIZE;
|
||||
inode->i_blocks = 0;
|
||||
inode->i_mapping->backing_dev_info = &relayfs_backing_dev_info;
|
||||
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
|
||||
switch (mode & S_IFMT) {
|
||||
case S_IFREG:
|
||||
inode->i_fop = fops;
|
||||
if (data)
|
||||
inode->u.generic_ip = data;
|
||||
break;
|
||||
case S_IFDIR:
|
||||
inode->i_op = &simple_dir_inode_operations;
|
||||
inode->i_fop = &simple_dir_operations;
|
||||
|
||||
/* directory inodes start off with i_nlink == 2 (for "." entry) */
|
||||
inode->i_nlink++;
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
|
||||
return inode;
|
||||
}
|
||||
|
||||
/**
|
||||
* relayfs_create_entry - create a relayfs directory or file
|
||||
* @name: the name of the file to create
|
||||
* @parent: parent directory
|
||||
* @mode: mode
|
||||
* @fops: file operations to use for the file
|
||||
* @data: user-associated data for this file
|
||||
*
|
||||
* Returns the new dentry, NULL on failure
|
||||
*
|
||||
* Creates a file or directory with the specifed permissions.
|
||||
*/
|
||||
static struct dentry *relayfs_create_entry(const char *name,
|
||||
struct dentry *parent,
|
||||
int mode,
|
||||
struct file_operations *fops,
|
||||
void *data)
|
||||
{
|
||||
struct dentry *d;
|
||||
struct inode *inode;
|
||||
int error = 0;
|
||||
|
||||
BUG_ON(!name || !(S_ISREG(mode) || S_ISDIR(mode)));
|
||||
|
||||
error = simple_pin_fs("relayfs", &relayfs_mount, &relayfs_mount_count);
|
||||
if (error) {
|
||||
printk(KERN_ERR "Couldn't mount relayfs: errcode %d\n", error);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
if (!parent && relayfs_mount && relayfs_mount->mnt_sb)
|
||||
parent = relayfs_mount->mnt_sb->s_root;
|
||||
|
||||
if (!parent) {
|
||||
simple_release_fs(&relayfs_mount, &relayfs_mount_count);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
parent = dget(parent);
|
||||
mutex_lock(&parent->d_inode->i_mutex);
|
||||
d = lookup_one_len(name, parent, strlen(name));
|
||||
if (IS_ERR(d)) {
|
||||
d = NULL;
|
||||
goto release_mount;
|
||||
}
|
||||
|
||||
if (d->d_inode) {
|
||||
d = NULL;
|
||||
goto release_mount;
|
||||
}
|
||||
|
||||
inode = relayfs_get_inode(parent->d_inode->i_sb, mode, fops, data);
|
||||
if (!inode) {
|
||||
d = NULL;
|
||||
goto release_mount;
|
||||
}
|
||||
|
||||
d_instantiate(d, inode);
|
||||
dget(d); /* Extra count - pin the dentry in core */
|
||||
|
||||
if (S_ISDIR(mode))
|
||||
parent->d_inode->i_nlink++;
|
||||
|
||||
goto exit;
|
||||
|
||||
release_mount:
|
||||
simple_release_fs(&relayfs_mount, &relayfs_mount_count);
|
||||
|
||||
exit:
|
||||
mutex_unlock(&parent->d_inode->i_mutex);
|
||||
dput(parent);
|
||||
return d;
|
||||
}
|
||||
|
||||
/**
|
||||
* relayfs_create_file - create a file in the relay filesystem
|
||||
* @name: the name of the file to create
|
||||
* @parent: parent directory
|
||||
* @mode: mode, if not specied the default perms are used
|
||||
* @fops: file operations to use for the file
|
||||
* @data: user-associated data for this file
|
||||
*
|
||||
* Returns file dentry if successful, NULL otherwise.
|
||||
*
|
||||
* The file will be created user r on behalf of current user.
|
||||
*/
|
||||
struct dentry *relayfs_create_file(const char *name,
|
||||
struct dentry *parent,
|
||||
int mode,
|
||||
struct file_operations *fops,
|
||||
void *data)
|
||||
{
|
||||
BUG_ON(!fops);
|
||||
|
||||
if (!mode)
|
||||
mode = S_IRUSR;
|
||||
mode = (mode & S_IALLUGO) | S_IFREG;
|
||||
|
||||
return relayfs_create_entry(name, parent, mode, fops, data);
|
||||
}
|
||||
|
||||
/**
|
||||
* relayfs_create_dir - create a directory in the relay filesystem
|
||||
* @name: the name of the directory to create
|
||||
* @parent: parent directory, NULL if parent should be fs root
|
||||
*
|
||||
* Returns directory dentry if successful, NULL otherwise.
|
||||
*
|
||||
* The directory will be created world rwx on behalf of current user.
|
||||
*/
|
||||
struct dentry *relayfs_create_dir(const char *name, struct dentry *parent)
|
||||
{
|
||||
int mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
|
||||
return relayfs_create_entry(name, parent, mode, NULL, NULL);
|
||||
}
|
||||
|
||||
/**
|
||||
* relayfs_remove - remove a file or directory in the relay filesystem
|
||||
* @dentry: file or directory dentry
|
||||
*
|
||||
* Returns 0 if successful, negative otherwise.
|
||||
*/
|
||||
int relayfs_remove(struct dentry *dentry)
|
||||
{
|
||||
struct dentry *parent;
|
||||
int error = 0;
|
||||
|
||||
if (!dentry)
|
||||
return -EINVAL;
|
||||
parent = dentry->d_parent;
|
||||
if (!parent)
|
||||
return -EINVAL;
|
||||
|
||||
parent = dget(parent);
|
||||
mutex_lock(&parent->d_inode->i_mutex);
|
||||
if (dentry->d_inode) {
|
||||
if (S_ISDIR(dentry->d_inode->i_mode))
|
||||
error = simple_rmdir(parent->d_inode, dentry);
|
||||
else
|
||||
error = simple_unlink(parent->d_inode, dentry);
|
||||
if (!error)
|
||||
d_delete(dentry);
|
||||
}
|
||||
if (!error)
|
||||
dput(dentry);
|
||||
mutex_unlock(&parent->d_inode->i_mutex);
|
||||
dput(parent);
|
||||
|
||||
if (!error)
|
||||
simple_release_fs(&relayfs_mount, &relayfs_mount_count);
|
||||
|
||||
return error;
|
||||
}
|
||||
|
||||
/**
|
||||
* relayfs_remove_file - remove a file from relay filesystem
|
||||
* @dentry: directory dentry
|
||||
*
|
||||
* Returns 0 if successful, negative otherwise.
|
||||
*/
|
||||
int relayfs_remove_file(struct dentry *dentry)
|
||||
{
|
||||
return relayfs_remove(dentry);
|
||||
}
|
||||
|
||||
/**
|
||||
* relayfs_remove_dir - remove a directory in the relay filesystem
|
||||
* @dentry: directory dentry
|
||||
*
|
||||
* Returns 0 if successful, negative otherwise.
|
||||
*/
|
||||
int relayfs_remove_dir(struct dentry *dentry)
|
||||
{
|
||||
return relayfs_remove(dentry);
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_open - open file op for relay files
|
||||
* @inode: the inode
|
||||
* @filp: the file
|
||||
*
|
||||
* Increments the channel buffer refcount.
|
||||
*/
|
||||
static int relay_file_open(struct inode *inode, struct file *filp)
|
||||
{
|
||||
struct rchan_buf *buf = inode->u.generic_ip;
|
||||
kref_get(&buf->kref);
|
||||
filp->private_data = buf;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_mmap - mmap file op for relay files
|
||||
* @filp: the file
|
||||
* @vma: the vma describing what to map
|
||||
*
|
||||
* Calls upon relay_mmap_buf to map the file into user space.
|
||||
*/
|
||||
static int relay_file_mmap(struct file *filp, struct vm_area_struct *vma)
|
||||
{
|
||||
struct rchan_buf *buf = filp->private_data;
|
||||
return relay_mmap_buf(buf, vma);
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_poll - poll file op for relay files
|
||||
* @filp: the file
|
||||
* @wait: poll table
|
||||
*
|
||||
* Poll implemention.
|
||||
*/
|
||||
static unsigned int relay_file_poll(struct file *filp, poll_table *wait)
|
||||
{
|
||||
unsigned int mask = 0;
|
||||
struct rchan_buf *buf = filp->private_data;
|
||||
|
||||
if (buf->finalized)
|
||||
return POLLERR;
|
||||
|
||||
if (filp->f_mode & FMODE_READ) {
|
||||
poll_wait(filp, &buf->read_wait, wait);
|
||||
if (!relay_buf_empty(buf))
|
||||
mask |= POLLIN | POLLRDNORM;
|
||||
}
|
||||
|
||||
return mask;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_release - release file op for relay files
|
||||
* @inode: the inode
|
||||
* @filp: the file
|
||||
*
|
||||
* Decrements the channel refcount, as the filesystem is
|
||||
* no longer using it.
|
||||
*/
|
||||
static int relay_file_release(struct inode *inode, struct file *filp)
|
||||
{
|
||||
struct rchan_buf *buf = filp->private_data;
|
||||
kref_put(&buf->kref, relay_remove_buf);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_read_consume - update the consumed count for the buffer
|
||||
*/
|
||||
static void relay_file_read_consume(struct rchan_buf *buf,
|
||||
size_t read_pos,
|
||||
size_t bytes_consumed)
|
||||
{
|
||||
size_t subbuf_size = buf->chan->subbuf_size;
|
||||
size_t n_subbufs = buf->chan->n_subbufs;
|
||||
size_t read_subbuf;
|
||||
|
||||
if (buf->bytes_consumed + bytes_consumed > subbuf_size) {
|
||||
relay_subbufs_consumed(buf->chan, buf->cpu, 1);
|
||||
buf->bytes_consumed = 0;
|
||||
}
|
||||
|
||||
buf->bytes_consumed += bytes_consumed;
|
||||
read_subbuf = read_pos / buf->chan->subbuf_size;
|
||||
if (buf->bytes_consumed + buf->padding[read_subbuf] == subbuf_size) {
|
||||
if ((read_subbuf == buf->subbufs_produced % n_subbufs) &&
|
||||
(buf->offset == subbuf_size))
|
||||
return;
|
||||
relay_subbufs_consumed(buf->chan, buf->cpu, 1);
|
||||
buf->bytes_consumed = 0;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_read_avail - boolean, are there unconsumed bytes available?
|
||||
*/
|
||||
static int relay_file_read_avail(struct rchan_buf *buf, size_t read_pos)
|
||||
{
|
||||
size_t bytes_produced, bytes_consumed, write_offset;
|
||||
size_t subbuf_size = buf->chan->subbuf_size;
|
||||
size_t n_subbufs = buf->chan->n_subbufs;
|
||||
size_t produced = buf->subbufs_produced % n_subbufs;
|
||||
size_t consumed = buf->subbufs_consumed % n_subbufs;
|
||||
|
||||
write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset;
|
||||
|
||||
if (consumed > produced) {
|
||||
if ((produced > n_subbufs) &&
|
||||
(produced + n_subbufs - consumed <= n_subbufs))
|
||||
produced += n_subbufs;
|
||||
} else if (consumed == produced) {
|
||||
if (buf->offset > subbuf_size) {
|
||||
produced += n_subbufs;
|
||||
if (buf->subbufs_produced == buf->subbufs_consumed)
|
||||
consumed += n_subbufs;
|
||||
}
|
||||
}
|
||||
|
||||
if (buf->offset > subbuf_size)
|
||||
bytes_produced = (produced - 1) * subbuf_size + write_offset;
|
||||
else
|
||||
bytes_produced = produced * subbuf_size + write_offset;
|
||||
bytes_consumed = consumed * subbuf_size + buf->bytes_consumed;
|
||||
|
||||
if (bytes_produced == bytes_consumed)
|
||||
return 0;
|
||||
|
||||
relay_file_read_consume(buf, read_pos, 0);
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_read_subbuf_avail - return bytes available in sub-buffer
|
||||
*/
|
||||
static size_t relay_file_read_subbuf_avail(size_t read_pos,
|
||||
struct rchan_buf *buf)
|
||||
{
|
||||
size_t padding, avail = 0;
|
||||
size_t read_subbuf, read_offset, write_subbuf, write_offset;
|
||||
size_t subbuf_size = buf->chan->subbuf_size;
|
||||
|
||||
write_subbuf = (buf->data - buf->start) / subbuf_size;
|
||||
write_offset = buf->offset > subbuf_size ? subbuf_size : buf->offset;
|
||||
read_subbuf = read_pos / subbuf_size;
|
||||
read_offset = read_pos % subbuf_size;
|
||||
padding = buf->padding[read_subbuf];
|
||||
|
||||
if (read_subbuf == write_subbuf) {
|
||||
if (read_offset + padding < write_offset)
|
||||
avail = write_offset - (read_offset + padding);
|
||||
} else
|
||||
avail = (subbuf_size - padding) - read_offset;
|
||||
|
||||
return avail;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_read_start_pos - find the first available byte to read
|
||||
*
|
||||
* If the read_pos is in the middle of padding, return the
|
||||
* position of the first actually available byte, otherwise
|
||||
* return the original value.
|
||||
*/
|
||||
static size_t relay_file_read_start_pos(size_t read_pos,
|
||||
struct rchan_buf *buf)
|
||||
{
|
||||
size_t read_subbuf, padding, padding_start, padding_end;
|
||||
size_t subbuf_size = buf->chan->subbuf_size;
|
||||
size_t n_subbufs = buf->chan->n_subbufs;
|
||||
|
||||
read_subbuf = read_pos / subbuf_size;
|
||||
padding = buf->padding[read_subbuf];
|
||||
padding_start = (read_subbuf + 1) * subbuf_size - padding;
|
||||
padding_end = (read_subbuf + 1) * subbuf_size;
|
||||
if (read_pos >= padding_start && read_pos < padding_end) {
|
||||
read_subbuf = (read_subbuf + 1) % n_subbufs;
|
||||
read_pos = read_subbuf * subbuf_size;
|
||||
}
|
||||
|
||||
return read_pos;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_read_end_pos - return the new read position
|
||||
*/
|
||||
static size_t relay_file_read_end_pos(struct rchan_buf *buf,
|
||||
size_t read_pos,
|
||||
size_t count)
|
||||
{
|
||||
size_t read_subbuf, padding, end_pos;
|
||||
size_t subbuf_size = buf->chan->subbuf_size;
|
||||
size_t n_subbufs = buf->chan->n_subbufs;
|
||||
|
||||
read_subbuf = read_pos / subbuf_size;
|
||||
padding = buf->padding[read_subbuf];
|
||||
if (read_pos % subbuf_size + count + padding == subbuf_size)
|
||||
end_pos = (read_subbuf + 1) * subbuf_size;
|
||||
else
|
||||
end_pos = read_pos + count;
|
||||
if (end_pos >= subbuf_size * n_subbufs)
|
||||
end_pos = 0;
|
||||
|
||||
return end_pos;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_file_read - read file op for relay files
|
||||
* @filp: the file
|
||||
* @buffer: the userspace buffer
|
||||
* @count: number of bytes to read
|
||||
* @ppos: position to read from
|
||||
*
|
||||
* Reads count bytes or the number of bytes available in the
|
||||
* current sub-buffer being read, whichever is smaller.
|
||||
*/
|
||||
static ssize_t relay_file_read(struct file *filp,
|
||||
char __user *buffer,
|
||||
size_t count,
|
||||
loff_t *ppos)
|
||||
{
|
||||
struct rchan_buf *buf = filp->private_data;
|
||||
struct inode *inode = filp->f_dentry->d_inode;
|
||||
size_t read_start, avail;
|
||||
ssize_t ret = 0;
|
||||
void *from;
|
||||
|
||||
mutex_lock(&inode->i_mutex);
|
||||
if(!relay_file_read_avail(buf, *ppos))
|
||||
goto out;
|
||||
|
||||
read_start = relay_file_read_start_pos(*ppos, buf);
|
||||
avail = relay_file_read_subbuf_avail(read_start, buf);
|
||||
if (!avail)
|
||||
goto out;
|
||||
|
||||
from = buf->start + read_start;
|
||||
ret = count = min(count, avail);
|
||||
if (copy_to_user(buffer, from, count)) {
|
||||
ret = -EFAULT;
|
||||
goto out;
|
||||
}
|
||||
relay_file_read_consume(buf, read_start, count);
|
||||
*ppos = relay_file_read_end_pos(buf, read_start, count);
|
||||
out:
|
||||
mutex_unlock(&inode->i_mutex);
|
||||
return ret;
|
||||
}
|
||||
|
||||
struct file_operations relay_file_operations = {
|
||||
.open = relay_file_open,
|
||||
.poll = relay_file_poll,
|
||||
.mmap = relay_file_mmap,
|
||||
.read = relay_file_read,
|
||||
.llseek = no_llseek,
|
||||
.release = relay_file_release,
|
||||
};
|
||||
|
||||
static struct super_operations relayfs_ops = {
|
||||
.statfs = simple_statfs,
|
||||
.drop_inode = generic_delete_inode,
|
||||
};
|
||||
|
||||
static int relayfs_fill_super(struct super_block * sb, void * data, int silent)
|
||||
{
|
||||
struct inode *inode;
|
||||
struct dentry *root;
|
||||
int mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
|
||||
|
||||
sb->s_blocksize = PAGE_CACHE_SIZE;
|
||||
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
|
||||
sb->s_magic = RELAYFS_MAGIC;
|
||||
sb->s_op = &relayfs_ops;
|
||||
inode = relayfs_get_inode(sb, mode, NULL, NULL);
|
||||
|
||||
if (!inode)
|
||||
return -ENOMEM;
|
||||
|
||||
root = d_alloc_root(inode);
|
||||
if (!root) {
|
||||
iput(inode);
|
||||
return -ENOMEM;
|
||||
}
|
||||
sb->s_root = root;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct super_block * relayfs_get_sb(struct file_system_type *fs_type,
|
||||
int flags, const char *dev_name,
|
||||
void *data)
|
||||
{
|
||||
return get_sb_single(fs_type, flags, data, relayfs_fill_super);
|
||||
}
|
||||
|
||||
static struct file_system_type relayfs_fs_type = {
|
||||
.owner = THIS_MODULE,
|
||||
.name = "relayfs",
|
||||
.get_sb = relayfs_get_sb,
|
||||
.kill_sb = kill_litter_super,
|
||||
};
|
||||
|
||||
static int __init init_relayfs_fs(void)
|
||||
{
|
||||
return register_filesystem(&relayfs_fs_type);
|
||||
}
|
||||
|
||||
static void __exit exit_relayfs_fs(void)
|
||||
{
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
unregister_filesystem(&relayfs_fs_type);
|
||||
}
|
||||
|
||||
module_init(init_relayfs_fs)
|
||||
module_exit(exit_relayfs_fs)
|
||||
|
||||
EXPORT_SYMBOL_GPL(relay_file_operations);
|
||||
EXPORT_SYMBOL_GPL(relayfs_create_dir);
|
||||
EXPORT_SYMBOL_GPL(relayfs_remove_dir);
|
||||
EXPORT_SYMBOL_GPL(relayfs_create_file);
|
||||
EXPORT_SYMBOL_GPL(relayfs_remove_file);
|
||||
|
||||
MODULE_AUTHOR("Tom Zanussi <zanussi@us.ibm.com> and Karim Yaghmour <karim@opersys.com>");
|
||||
MODULE_DESCRIPTION("Relay Filesystem");
|
||||
MODULE_LICENSE("GPL");
|
||||
|
@ -1,482 +0,0 @@
|
||||
/*
|
||||
* Public API and common code for RelayFS.
|
||||
*
|
||||
* See Documentation/filesystems/relayfs.txt for an overview of relayfs.
|
||||
*
|
||||
* Copyright (C) 2002-2005 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp
|
||||
* Copyright (C) 1999-2005 - Karim Yaghmour (karim@opersys.com)
|
||||
*
|
||||
* This file is released under the GPL.
|
||||
*/
|
||||
|
||||
#include <linux/errno.h>
|
||||
#include <linux/stddef.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/string.h>
|
||||
#include <linux/relayfs_fs.h>
|
||||
#include "relay.h"
|
||||
#include "buffers.h"
|
||||
|
||||
/**
|
||||
* relay_buf_empty - boolean, is the channel buffer empty?
|
||||
* @buf: channel buffer
|
||||
*
|
||||
* Returns 1 if the buffer is empty, 0 otherwise.
|
||||
*/
|
||||
int relay_buf_empty(struct rchan_buf *buf)
|
||||
{
|
||||
return (buf->subbufs_produced - buf->subbufs_consumed) ? 0 : 1;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_buf_full - boolean, is the channel buffer full?
|
||||
* @buf: channel buffer
|
||||
*
|
||||
* Returns 1 if the buffer is full, 0 otherwise.
|
||||
*/
|
||||
int relay_buf_full(struct rchan_buf *buf)
|
||||
{
|
||||
size_t ready = buf->subbufs_produced - buf->subbufs_consumed;
|
||||
return (ready >= buf->chan->n_subbufs) ? 1 : 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* High-level relayfs kernel API and associated functions.
|
||||
*/
|
||||
|
||||
/*
|
||||
* rchan_callback implementations defining default channel behavior. Used
|
||||
* in place of corresponding NULL values in client callback struct.
|
||||
*/
|
||||
|
||||
/*
|
||||
* subbuf_start() default callback. Does nothing.
|
||||
*/
|
||||
static int subbuf_start_default_callback (struct rchan_buf *buf,
|
||||
void *subbuf,
|
||||
void *prev_subbuf,
|
||||
size_t prev_padding)
|
||||
{
|
||||
if (relay_buf_full(buf))
|
||||
return 0;
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
/*
|
||||
* buf_mapped() default callback. Does nothing.
|
||||
*/
|
||||
static void buf_mapped_default_callback(struct rchan_buf *buf,
|
||||
struct file *filp)
|
||||
{
|
||||
}
|
||||
|
||||
/*
|
||||
* buf_unmapped() default callback. Does nothing.
|
||||
*/
|
||||
static void buf_unmapped_default_callback(struct rchan_buf *buf,
|
||||
struct file *filp)
|
||||
{
|
||||
}
|
||||
|
||||
/*
|
||||
* create_buf_file_create() default callback. Creates file to represent buf.
|
||||
*/
|
||||
static struct dentry *create_buf_file_default_callback(const char *filename,
|
||||
struct dentry *parent,
|
||||
int mode,
|
||||
struct rchan_buf *buf,
|
||||
int *is_global)
|
||||
{
|
||||
return relayfs_create_file(filename, parent, mode,
|
||||
&relay_file_operations, buf);
|
||||
}
|
||||
|
||||
/*
|
||||
* remove_buf_file() default callback. Removes file representing relay buffer.
|
||||
*/
|
||||
static int remove_buf_file_default_callback(struct dentry *dentry)
|
||||
{
|
||||
return relayfs_remove(dentry);
|
||||
}
|
||||
|
||||
/* relay channel default callbacks */
|
||||
static struct rchan_callbacks default_channel_callbacks = {
|
||||
.subbuf_start = subbuf_start_default_callback,
|
||||
.buf_mapped = buf_mapped_default_callback,
|
||||
.buf_unmapped = buf_unmapped_default_callback,
|
||||
.create_buf_file = create_buf_file_default_callback,
|
||||
.remove_buf_file = remove_buf_file_default_callback,
|
||||
};
|
||||
|
||||
/**
|
||||
* wakeup_readers - wake up readers waiting on a channel
|
||||
* @private: the channel buffer
|
||||
*
|
||||
* This is the work function used to defer reader waking. The
|
||||
* reason waking is deferred is that calling directly from write
|
||||
* causes problems if you're writing from say the scheduler.
|
||||
*/
|
||||
static void wakeup_readers(void *private)
|
||||
{
|
||||
struct rchan_buf *buf = private;
|
||||
wake_up_interruptible(&buf->read_wait);
|
||||
}
|
||||
|
||||
/**
|
||||
* __relay_reset - reset a channel buffer
|
||||
* @buf: the channel buffer
|
||||
* @init: 1 if this is a first-time initialization
|
||||
*
|
||||
* See relay_reset for description of effect.
|
||||
*/
|
||||
static inline void __relay_reset(struct rchan_buf *buf, unsigned int init)
|
||||
{
|
||||
size_t i;
|
||||
|
||||
if (init) {
|
||||
init_waitqueue_head(&buf->read_wait);
|
||||
kref_init(&buf->kref);
|
||||
INIT_WORK(&buf->wake_readers, NULL, NULL);
|
||||
} else {
|
||||
cancel_delayed_work(&buf->wake_readers);
|
||||
flush_scheduled_work();
|
||||
}
|
||||
|
||||
buf->subbufs_produced = 0;
|
||||
buf->subbufs_consumed = 0;
|
||||
buf->bytes_consumed = 0;
|
||||
buf->finalized = 0;
|
||||
buf->data = buf->start;
|
||||
buf->offset = 0;
|
||||
|
||||
for (i = 0; i < buf->chan->n_subbufs; i++)
|
||||
buf->padding[i] = 0;
|
||||
|
||||
buf->chan->cb->subbuf_start(buf, buf->data, NULL, 0);
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_reset - reset the channel
|
||||
* @chan: the channel
|
||||
*
|
||||
* This has the effect of erasing all data from all channel buffers
|
||||
* and restarting the channel in its initial state. The buffers
|
||||
* are not freed, so any mappings are still in effect.
|
||||
*
|
||||
* NOTE: Care should be taken that the channel isn't actually
|
||||
* being used by anything when this call is made.
|
||||
*/
|
||||
void relay_reset(struct rchan *chan)
|
||||
{
|
||||
unsigned int i;
|
||||
struct rchan_buf *prev = NULL;
|
||||
|
||||
if (!chan)
|
||||
return;
|
||||
|
||||
for (i = 0; i < NR_CPUS; i++) {
|
||||
if (!chan->buf[i] || chan->buf[i] == prev)
|
||||
break;
|
||||
__relay_reset(chan->buf[i], 0);
|
||||
prev = chan->buf[i];
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_open_buf - create a new channel buffer in relayfs
|
||||
*
|
||||
* Internal - used by relay_open().
|
||||
*/
|
||||
static struct rchan_buf *relay_open_buf(struct rchan *chan,
|
||||
const char *filename,
|
||||
struct dentry *parent,
|
||||
int *is_global)
|
||||
{
|
||||
struct rchan_buf *buf;
|
||||
struct dentry *dentry;
|
||||
|
||||
if (*is_global)
|
||||
return chan->buf[0];
|
||||
|
||||
buf = relay_create_buf(chan);
|
||||
if (!buf)
|
||||
return NULL;
|
||||
|
||||
/* Create file in fs */
|
||||
dentry = chan->cb->create_buf_file(filename, parent, S_IRUSR,
|
||||
buf, is_global);
|
||||
if (!dentry) {
|
||||
relay_destroy_buf(buf);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
buf->dentry = dentry;
|
||||
__relay_reset(buf, 1);
|
||||
|
||||
return buf;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_close_buf - close a channel buffer
|
||||
* @buf: channel buffer
|
||||
*
|
||||
* Marks the buffer finalized and restores the default callbacks.
|
||||
* The channel buffer and channel buffer data structure are then freed
|
||||
* automatically when the last reference is given up.
|
||||
*/
|
||||
static inline void relay_close_buf(struct rchan_buf *buf)
|
||||
{
|
||||
buf->finalized = 1;
|
||||
buf->chan->cb = &default_channel_callbacks;
|
||||
cancel_delayed_work(&buf->wake_readers);
|
||||
flush_scheduled_work();
|
||||
kref_put(&buf->kref, relay_remove_buf);
|
||||
}
|
||||
|
||||
static inline void setup_callbacks(struct rchan *chan,
|
||||
struct rchan_callbacks *cb)
|
||||
{
|
||||
if (!cb) {
|
||||
chan->cb = &default_channel_callbacks;
|
||||
return;
|
||||
}
|
||||
|
||||
if (!cb->subbuf_start)
|
||||
cb->subbuf_start = subbuf_start_default_callback;
|
||||
if (!cb->buf_mapped)
|
||||
cb->buf_mapped = buf_mapped_default_callback;
|
||||
if (!cb->buf_unmapped)
|
||||
cb->buf_unmapped = buf_unmapped_default_callback;
|
||||
if (!cb->create_buf_file)
|
||||
cb->create_buf_file = create_buf_file_default_callback;
|
||||
if (!cb->remove_buf_file)
|
||||
cb->remove_buf_file = remove_buf_file_default_callback;
|
||||
chan->cb = cb;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_open - create a new relayfs channel
|
||||
* @base_filename: base name of files to create
|
||||
* @parent: dentry of parent directory, NULL for root directory
|
||||
* @subbuf_size: size of sub-buffers
|
||||
* @n_subbufs: number of sub-buffers
|
||||
* @cb: client callback functions
|
||||
*
|
||||
* Returns channel pointer if successful, NULL otherwise.
|
||||
*
|
||||
* Creates a channel buffer for each cpu using the sizes and
|
||||
* attributes specified. The created channel buffer files
|
||||
* will be named base_filename0...base_filenameN-1. File
|
||||
* permissions will be S_IRUSR.
|
||||
*/
|
||||
struct rchan *relay_open(const char *base_filename,
|
||||
struct dentry *parent,
|
||||
size_t subbuf_size,
|
||||
size_t n_subbufs,
|
||||
struct rchan_callbacks *cb)
|
||||
{
|
||||
unsigned int i;
|
||||
struct rchan *chan;
|
||||
char *tmpname;
|
||||
int is_global = 0;
|
||||
|
||||
if (!base_filename)
|
||||
return NULL;
|
||||
|
||||
if (!(subbuf_size && n_subbufs))
|
||||
return NULL;
|
||||
|
||||
chan = kcalloc(1, sizeof(struct rchan), GFP_KERNEL);
|
||||
if (!chan)
|
||||
return NULL;
|
||||
|
||||
chan->version = RELAYFS_CHANNEL_VERSION;
|
||||
chan->n_subbufs = n_subbufs;
|
||||
chan->subbuf_size = subbuf_size;
|
||||
chan->alloc_size = FIX_SIZE(subbuf_size * n_subbufs);
|
||||
setup_callbacks(chan, cb);
|
||||
kref_init(&chan->kref);
|
||||
|
||||
tmpname = kmalloc(NAME_MAX + 1, GFP_KERNEL);
|
||||
if (!tmpname)
|
||||
goto free_chan;
|
||||
|
||||
for_each_online_cpu(i) {
|
||||
sprintf(tmpname, "%s%d", base_filename, i);
|
||||
chan->buf[i] = relay_open_buf(chan, tmpname, parent,
|
||||
&is_global);
|
||||
chan->buf[i]->cpu = i;
|
||||
if (!chan->buf[i])
|
||||
goto free_bufs;
|
||||
}
|
||||
|
||||
kfree(tmpname);
|
||||
return chan;
|
||||
|
||||
free_bufs:
|
||||
for (i = 0; i < NR_CPUS; i++) {
|
||||
if (!chan->buf[i])
|
||||
break;
|
||||
relay_close_buf(chan->buf[i]);
|
||||
if (is_global)
|
||||
break;
|
||||
}
|
||||
kfree(tmpname);
|
||||
|
||||
free_chan:
|
||||
kref_put(&chan->kref, relay_destroy_channel);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_switch_subbuf - switch to a new sub-buffer
|
||||
* @buf: channel buffer
|
||||
* @length: size of current event
|
||||
*
|
||||
* Returns either the length passed in or 0 if full.
|
||||
|
||||
* Performs sub-buffer-switch tasks such as invoking callbacks,
|
||||
* updating padding counts, waking up readers, etc.
|
||||
*/
|
||||
size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length)
|
||||
{
|
||||
void *old, *new;
|
||||
size_t old_subbuf, new_subbuf;
|
||||
|
||||
if (unlikely(length > buf->chan->subbuf_size))
|
||||
goto toobig;
|
||||
|
||||
if (buf->offset != buf->chan->subbuf_size + 1) {
|
||||
buf->prev_padding = buf->chan->subbuf_size - buf->offset;
|
||||
old_subbuf = buf->subbufs_produced % buf->chan->n_subbufs;
|
||||
buf->padding[old_subbuf] = buf->prev_padding;
|
||||
buf->subbufs_produced++;
|
||||
if (waitqueue_active(&buf->read_wait)) {
|
||||
PREPARE_WORK(&buf->wake_readers, wakeup_readers, buf);
|
||||
schedule_delayed_work(&buf->wake_readers, 1);
|
||||
}
|
||||
}
|
||||
|
||||
old = buf->data;
|
||||
new_subbuf = buf->subbufs_produced % buf->chan->n_subbufs;
|
||||
new = buf->start + new_subbuf * buf->chan->subbuf_size;
|
||||
buf->offset = 0;
|
||||
if (!buf->chan->cb->subbuf_start(buf, new, old, buf->prev_padding)) {
|
||||
buf->offset = buf->chan->subbuf_size + 1;
|
||||
return 0;
|
||||
}
|
||||
buf->data = new;
|
||||
buf->padding[new_subbuf] = 0;
|
||||
|
||||
if (unlikely(length + buf->offset > buf->chan->subbuf_size))
|
||||
goto toobig;
|
||||
|
||||
return length;
|
||||
|
||||
toobig:
|
||||
buf->chan->last_toobig = length;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_subbufs_consumed - update the buffer's sub-buffers-consumed count
|
||||
* @chan: the channel
|
||||
* @cpu: the cpu associated with the channel buffer to update
|
||||
* @subbufs_consumed: number of sub-buffers to add to current buf's count
|
||||
*
|
||||
* Adds to the channel buffer's consumed sub-buffer count.
|
||||
* subbufs_consumed should be the number of sub-buffers newly consumed,
|
||||
* not the total consumed.
|
||||
*
|
||||
* NOTE: kernel clients don't need to call this function if the channel
|
||||
* mode is 'overwrite'.
|
||||
*/
|
||||
void relay_subbufs_consumed(struct rchan *chan,
|
||||
unsigned int cpu,
|
||||
size_t subbufs_consumed)
|
||||
{
|
||||
struct rchan_buf *buf;
|
||||
|
||||
if (!chan)
|
||||
return;
|
||||
|
||||
if (cpu >= NR_CPUS || !chan->buf[cpu])
|
||||
return;
|
||||
|
||||
buf = chan->buf[cpu];
|
||||
buf->subbufs_consumed += subbufs_consumed;
|
||||
if (buf->subbufs_consumed > buf->subbufs_produced)
|
||||
buf->subbufs_consumed = buf->subbufs_produced;
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_destroy_channel - free the channel struct
|
||||
*
|
||||
* Should only be called from kref_put().
|
||||
*/
|
||||
void relay_destroy_channel(struct kref *kref)
|
||||
{
|
||||
struct rchan *chan = container_of(kref, struct rchan, kref);
|
||||
kfree(chan);
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_close - close the channel
|
||||
* @chan: the channel
|
||||
*
|
||||
* Closes all channel buffers and frees the channel.
|
||||
*/
|
||||
void relay_close(struct rchan *chan)
|
||||
{
|
||||
unsigned int i;
|
||||
struct rchan_buf *prev = NULL;
|
||||
|
||||
if (!chan)
|
||||
return;
|
||||
|
||||
for (i = 0; i < NR_CPUS; i++) {
|
||||
if (!chan->buf[i] || chan->buf[i] == prev)
|
||||
break;
|
||||
relay_close_buf(chan->buf[i]);
|
||||
prev = chan->buf[i];
|
||||
}
|
||||
|
||||
if (chan->last_toobig)
|
||||
printk(KERN_WARNING "relayfs: one or more items not logged "
|
||||
"[item size (%Zd) > sub-buffer size (%Zd)]\n",
|
||||
chan->last_toobig, chan->subbuf_size);
|
||||
|
||||
kref_put(&chan->kref, relay_destroy_channel);
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_flush - close the channel
|
||||
* @chan: the channel
|
||||
*
|
||||
* Flushes all channel buffers i.e. forces buffer switch.
|
||||
*/
|
||||
void relay_flush(struct rchan *chan)
|
||||
{
|
||||
unsigned int i;
|
||||
struct rchan_buf *prev = NULL;
|
||||
|
||||
if (!chan)
|
||||
return;
|
||||
|
||||
for (i = 0; i < NR_CPUS; i++) {
|
||||
if (!chan->buf[i] || chan->buf[i] == prev)
|
||||
break;
|
||||
relay_switch_subbuf(chan->buf[i], 0);
|
||||
prev = chan->buf[i];
|
||||
}
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL_GPL(relay_open);
|
||||
EXPORT_SYMBOL_GPL(relay_close);
|
||||
EXPORT_SYMBOL_GPL(relay_flush);
|
||||
EXPORT_SYMBOL_GPL(relay_reset);
|
||||
EXPORT_SYMBOL_GPL(relay_subbufs_consumed);
|
||||
EXPORT_SYMBOL_GPL(relay_switch_subbuf);
|
||||
EXPORT_SYMBOL_GPL(relay_buf_full);
|
@ -1,8 +0,0 @@
|
||||
#ifndef _RELAY_H
|
||||
#define _RELAY_H
|
||||
|
||||
extern int relayfs_remove(struct dentry *dentry);
|
||||
extern int relay_buf_empty(struct rchan_buf *buf);
|
||||
extern void relay_destroy_channel(struct kref *kref);
|
||||
|
||||
#endif /* _RELAY_H */
|
@ -22,6 +22,7 @@ typedef struct request_queue request_queue_t;
|
||||
struct elevator_queue;
|
||||
typedef struct elevator_queue elevator_t;
|
||||
struct request_pm_state;
|
||||
struct blk_trace;
|
||||
|
||||
#define BLKDEV_MIN_RQ 4
|
||||
#define BLKDEV_MAX_RQ 128 /* Default maximum */
|
||||
@ -416,6 +417,8 @@ struct request_queue
|
||||
unsigned int sg_reserved_size;
|
||||
int node;
|
||||
|
||||
struct blk_trace *blk_trace;
|
||||
|
||||
/*
|
||||
* reserved for flush operations
|
||||
*/
|
||||
|
277
include/linux/blktrace_api.h
Normal file
277
include/linux/blktrace_api.h
Normal file
@ -0,0 +1,277 @@
|
||||
#ifndef BLKTRACE_H
|
||||
#define BLKTRACE_H
|
||||
|
||||
#include <linux/config.h>
|
||||
#include <linux/blkdev.h>
|
||||
#include <linux/relay.h>
|
||||
|
||||
/*
|
||||
* Trace categories
|
||||
*/
|
||||
enum blktrace_cat {
|
||||
BLK_TC_READ = 1 << 0, /* reads */
|
||||
BLK_TC_WRITE = 1 << 1, /* writes */
|
||||
BLK_TC_BARRIER = 1 << 2, /* barrier */
|
||||
BLK_TC_SYNC = 1 << 3, /* barrier */
|
||||
BLK_TC_QUEUE = 1 << 4, /* queueing/merging */
|
||||
BLK_TC_REQUEUE = 1 << 5, /* requeueing */
|
||||
BLK_TC_ISSUE = 1 << 6, /* issue */
|
||||
BLK_TC_COMPLETE = 1 << 7, /* completions */
|
||||
BLK_TC_FS = 1 << 8, /* fs requests */
|
||||
BLK_TC_PC = 1 << 9, /* pc requests */
|
||||
BLK_TC_NOTIFY = 1 << 10, /* special message */
|
||||
|
||||
BLK_TC_END = 1 << 15, /* only 16-bits, reminder */
|
||||
};
|
||||
|
||||
#define BLK_TC_SHIFT (16)
|
||||
#define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT)
|
||||
|
||||
/*
|
||||
* Basic trace actions
|
||||
*/
|
||||
enum blktrace_act {
|
||||
__BLK_TA_QUEUE = 1, /* queued */
|
||||
__BLK_TA_BACKMERGE, /* back merged to existing rq */
|
||||
__BLK_TA_FRONTMERGE, /* front merge to existing rq */
|
||||
__BLK_TA_GETRQ, /* allocated new request */
|
||||
__BLK_TA_SLEEPRQ, /* sleeping on rq allocation */
|
||||
__BLK_TA_REQUEUE, /* request requeued */
|
||||
__BLK_TA_ISSUE, /* sent to driver */
|
||||
__BLK_TA_COMPLETE, /* completed by driver */
|
||||
__BLK_TA_PLUG, /* queue was plugged */
|
||||
__BLK_TA_UNPLUG_IO, /* queue was unplugged by io */
|
||||
__BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */
|
||||
__BLK_TA_INSERT, /* insert request */
|
||||
__BLK_TA_SPLIT, /* bio was split */
|
||||
__BLK_TA_BOUNCE, /* bio was bounced */
|
||||
__BLK_TA_REMAP, /* bio was remapped */
|
||||
};
|
||||
|
||||
/*
|
||||
* Trace actions in full. Additionally, read or write is masked
|
||||
*/
|
||||
#define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
#define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
#define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
#define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
#define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
#define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE))
|
||||
#define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE))
|
||||
#define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE))
|
||||
#define BLK_TA_PLUG (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
#define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
#define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
#define BLK_TA_INSERT (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
#define BLK_TA_SPLIT (__BLK_TA_SPLIT)
|
||||
#define BLK_TA_BOUNCE (__BLK_TA_BOUNCE)
|
||||
#define BLK_TA_REMAP (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE))
|
||||
|
||||
#define BLK_IO_TRACE_MAGIC 0x65617400
|
||||
#define BLK_IO_TRACE_VERSION 0x07
|
||||
|
||||
/*
|
||||
* The trace itself
|
||||
*/
|
||||
struct blk_io_trace {
|
||||
u32 magic; /* MAGIC << 8 | version */
|
||||
u32 sequence; /* event number */
|
||||
u64 time; /* in microseconds */
|
||||
u64 sector; /* disk offset */
|
||||
u32 bytes; /* transfer length */
|
||||
u32 action; /* what happened */
|
||||
u32 pid; /* who did it */
|
||||
u32 device; /* device number */
|
||||
u32 cpu; /* on what cpu did it happen */
|
||||
u16 error; /* completion error */
|
||||
u16 pdu_len; /* length of data after this trace */
|
||||
};
|
||||
|
||||
/*
|
||||
* The remap event
|
||||
*/
|
||||
struct blk_io_trace_remap {
|
||||
u32 device;
|
||||
u32 __pad;
|
||||
u64 sector;
|
||||
};
|
||||
|
||||
enum {
|
||||
Blktrace_setup = 1,
|
||||
Blktrace_running,
|
||||
Blktrace_stopped,
|
||||
};
|
||||
|
||||
struct blk_trace {
|
||||
int trace_state;
|
||||
struct rchan *rchan;
|
||||
unsigned long *sequence;
|
||||
u16 act_mask;
|
||||
u64 start_lba;
|
||||
u64 end_lba;
|
||||
u32 pid;
|
||||
u32 dev;
|
||||
struct dentry *dir;
|
||||
struct dentry *dropped_file;
|
||||
atomic_t dropped;
|
||||
};
|
||||
|
||||
/*
|
||||
* User setup structure passed with BLKTRACESTART
|
||||
*/
|
||||
struct blk_user_trace_setup {
|
||||
char name[BDEVNAME_SIZE]; /* output */
|
||||
u16 act_mask; /* input */
|
||||
u32 buf_size; /* input */
|
||||
u32 buf_nr; /* input */
|
||||
u64 start_lba;
|
||||
u64 end_lba;
|
||||
u32 pid;
|
||||
};
|
||||
|
||||
#if defined(CONFIG_BLK_DEV_IO_TRACE)
|
||||
extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
|
||||
extern void blk_trace_shutdown(request_queue_t *);
|
||||
extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *);
|
||||
|
||||
/**
|
||||
* blk_add_trace_rq - Add a trace for a request oriented action
|
||||
* @q: queue the io is for
|
||||
* @rq: the source request
|
||||
* @what: the action
|
||||
*
|
||||
* Description:
|
||||
* Records an action against a request. Will log the bio offset + size.
|
||||
*
|
||||
**/
|
||||
static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq,
|
||||
u32 what)
|
||||
{
|
||||
struct blk_trace *bt = q->blk_trace;
|
||||
int rw = rq->flags & 0x07;
|
||||
|
||||
if (likely(!bt))
|
||||
return;
|
||||
|
||||
if (blk_pc_request(rq)) {
|
||||
what |= BLK_TC_ACT(BLK_TC_PC);
|
||||
__blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd);
|
||||
} else {
|
||||
what |= BLK_TC_ACT(BLK_TC_FS);
|
||||
__blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* blk_add_trace_bio - Add a trace for a bio oriented action
|
||||
* @q: queue the io is for
|
||||
* @bio: the source bio
|
||||
* @what: the action
|
||||
*
|
||||
* Description:
|
||||
* Records an action against a bio. Will log the bio offset + size.
|
||||
*
|
||||
**/
|
||||
static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio,
|
||||
u32 what)
|
||||
{
|
||||
struct blk_trace *bt = q->blk_trace;
|
||||
|
||||
if (likely(!bt))
|
||||
return;
|
||||
|
||||
__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL);
|
||||
}
|
||||
|
||||
/**
|
||||
* blk_add_trace_generic - Add a trace for a generic action
|
||||
* @q: queue the io is for
|
||||
* @bio: the source bio
|
||||
* @rw: the data direction
|
||||
* @what: the action
|
||||
*
|
||||
* Description:
|
||||
* Records a simple trace
|
||||
*
|
||||
**/
|
||||
static inline void blk_add_trace_generic(struct request_queue *q,
|
||||
struct bio *bio, int rw, u32 what)
|
||||
{
|
||||
struct blk_trace *bt = q->blk_trace;
|
||||
|
||||
if (likely(!bt))
|
||||
return;
|
||||
|
||||
if (bio)
|
||||
blk_add_trace_bio(q, bio, what);
|
||||
else
|
||||
__blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL);
|
||||
}
|
||||
|
||||
/**
|
||||
* blk_add_trace_pdu_int - Add a trace for a bio with an integer payload
|
||||
* @q: queue the io is for
|
||||
* @what: the action
|
||||
* @bio: the source bio
|
||||
* @pdu: the integer payload
|
||||
*
|
||||
* Description:
|
||||
* Adds a trace with some integer payload. This might be an unplug
|
||||
* option given as the action, with the depth at unplug time given
|
||||
* as the payload
|
||||
*
|
||||
**/
|
||||
static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what,
|
||||
struct bio *bio, unsigned int pdu)
|
||||
{
|
||||
struct blk_trace *bt = q->blk_trace;
|
||||
u64 rpdu = cpu_to_be64(pdu);
|
||||
|
||||
if (likely(!bt))
|
||||
return;
|
||||
|
||||
if (bio)
|
||||
__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu);
|
||||
else
|
||||
__blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu);
|
||||
}
|
||||
|
||||
/**
|
||||
* blk_add_trace_remap - Add a trace for a remap operation
|
||||
* @q: queue the io is for
|
||||
* @bio: the source bio
|
||||
* @dev: target device
|
||||
* @from: source sector
|
||||
* @to: target sector
|
||||
*
|
||||
* Description:
|
||||
* Device mapper or raid target sometimes need to split a bio because
|
||||
* it spans a stripe (or similar). Add a trace for that action.
|
||||
*
|
||||
**/
|
||||
static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio,
|
||||
dev_t dev, sector_t from, sector_t to)
|
||||
{
|
||||
struct blk_trace *bt = q->blk_trace;
|
||||
struct blk_io_trace_remap r;
|
||||
|
||||
if (likely(!bt))
|
||||
return;
|
||||
|
||||
r.device = cpu_to_be32(dev);
|
||||
r.sector = cpu_to_be64(to);
|
||||
|
||||
__blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r);
|
||||
}
|
||||
|
||||
#else /* !CONFIG_BLK_DEV_IO_TRACE */
|
||||
#define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY)
|
||||
#define blk_trace_shutdown(q) do { } while (0)
|
||||
#define blk_add_trace_rq(q, rq, what) do { } while (0)
|
||||
#define blk_add_trace_bio(q, rq, what) do { } while (0)
|
||||
#define blk_add_trace_generic(q, rq, rw, what) do { } while (0)
|
||||
#define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0)
|
||||
#define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0)
|
||||
#endif /* CONFIG_BLK_DEV_IO_TRACE */
|
||||
|
||||
#endif
|
@ -97,6 +97,10 @@ COMPATIBLE_IOCTL(BLKRRPART)
|
||||
COMPATIBLE_IOCTL(BLKFLSBUF)
|
||||
COMPATIBLE_IOCTL(BLKSECTSET)
|
||||
COMPATIBLE_IOCTL(BLKSSZGET)
|
||||
COMPATIBLE_IOCTL(BLKTRACESTART)
|
||||
COMPATIBLE_IOCTL(BLKTRACESTOP)
|
||||
COMPATIBLE_IOCTL(BLKTRACESETUP)
|
||||
COMPATIBLE_IOCTL(BLKTRACETEARDOWN)
|
||||
ULONG_IOCTL(BLKRASET)
|
||||
ULONG_IOCTL(BLKFRASET)
|
||||
/* RAID */
|
||||
|
@ -197,6 +197,10 @@ extern int dir_notify_enable;
|
||||
#define BLKBSZGET _IOR(0x12,112,size_t)
|
||||
#define BLKBSZSET _IOW(0x12,113,size_t)
|
||||
#define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
|
||||
#define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
|
||||
#define BLKTRACESTART _IO(0x12,116)
|
||||
#define BLKTRACESTOP _IO(0x12,117)
|
||||
#define BLKTRACETEARDOWN _IO(0x12,118)
|
||||
|
||||
#define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
|
||||
#define FIBMAP _IO(0x00,1) /* bmap access */
|
||||
|
281
include/linux/relay.h
Normal file
281
include/linux/relay.h
Normal file
@ -0,0 +1,281 @@
|
||||
/*
|
||||
* linux/include/linux/relay.h
|
||||
*
|
||||
* Copyright (C) 2002, 2003 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp
|
||||
* Copyright (C) 1999, 2000, 2001, 2002 - Karim Yaghmour (karim@opersys.com)
|
||||
*
|
||||
* CONFIG_RELAY definitions and declarations
|
||||
*/
|
||||
|
||||
#ifndef _LINUX_RELAY_H
|
||||
#define _LINUX_RELAY_H
|
||||
|
||||
#include <linux/config.h>
|
||||
#include <linux/types.h>
|
||||
#include <linux/sched.h>
|
||||
#include <linux/wait.h>
|
||||
#include <linux/list.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/poll.h>
|
||||
#include <linux/kref.h>
|
||||
|
||||
/* Needs a _much_ better name... */
|
||||
#define FIX_SIZE(x) ((((x) - 1) & PAGE_MASK) + PAGE_SIZE)
|
||||
|
||||
/*
|
||||
* Tracks changes to rchan/rchan_buf structs
|
||||
*/
|
||||
#define RELAYFS_CHANNEL_VERSION 6
|
||||
|
||||
/*
|
||||
* Per-cpu relay channel buffer
|
||||
*/
|
||||
struct rchan_buf
|
||||
{
|
||||
void *start; /* start of channel buffer */
|
||||
void *data; /* start of current sub-buffer */
|
||||
size_t offset; /* current offset into sub-buffer */
|
||||
size_t subbufs_produced; /* count of sub-buffers produced */
|
||||
size_t subbufs_consumed; /* count of sub-buffers consumed */
|
||||
struct rchan *chan; /* associated channel */
|
||||
wait_queue_head_t read_wait; /* reader wait queue */
|
||||
struct work_struct wake_readers; /* reader wake-up work struct */
|
||||
struct dentry *dentry; /* channel file dentry */
|
||||
struct kref kref; /* channel buffer refcount */
|
||||
struct page **page_array; /* array of current buffer pages */
|
||||
unsigned int page_count; /* number of current buffer pages */
|
||||
unsigned int finalized; /* buffer has been finalized */
|
||||
size_t *padding; /* padding counts per sub-buffer */
|
||||
size_t prev_padding; /* temporary variable */
|
||||
size_t bytes_consumed; /* bytes consumed in cur read subbuf */
|
||||
unsigned int cpu; /* this buf's cpu */
|
||||
} ____cacheline_aligned;
|
||||
|
||||
/*
|
||||
* Relay channel data structure
|
||||
*/
|
||||
struct rchan
|
||||
{
|
||||
u32 version; /* the version of this struct */
|
||||
size_t subbuf_size; /* sub-buffer size */
|
||||
size_t n_subbufs; /* number of sub-buffers per buffer */
|
||||
size_t alloc_size; /* total buffer size allocated */
|
||||
struct rchan_callbacks *cb; /* client callbacks */
|
||||
struct kref kref; /* channel refcount */
|
||||
void *private_data; /* for user-defined data */
|
||||
size_t last_toobig; /* tried to log event > subbuf size */
|
||||
struct rchan_buf *buf[NR_CPUS]; /* per-cpu channel buffers */
|
||||
};
|
||||
|
||||
/*
|
||||
* Relay channel client callbacks
|
||||
*/
|
||||
struct rchan_callbacks
|
||||
{
|
||||
/*
|
||||
* subbuf_start - called on buffer-switch to a new sub-buffer
|
||||
* @buf: the channel buffer containing the new sub-buffer
|
||||
* @subbuf: the start of the new sub-buffer
|
||||
* @prev_subbuf: the start of the previous sub-buffer
|
||||
* @prev_padding: unused space at the end of previous sub-buffer
|
||||
*
|
||||
* The client should return 1 to continue logging, 0 to stop
|
||||
* logging.
|
||||
*
|
||||
* NOTE: subbuf_start will also be invoked when the buffer is
|
||||
* created, so that the first sub-buffer can be initialized
|
||||
* if necessary. In this case, prev_subbuf will be NULL.
|
||||
*
|
||||
* NOTE: the client can reserve bytes at the beginning of the new
|
||||
* sub-buffer by calling subbuf_start_reserve() in this callback.
|
||||
*/
|
||||
int (*subbuf_start) (struct rchan_buf *buf,
|
||||
void *subbuf,
|
||||
void *prev_subbuf,
|
||||
size_t prev_padding);
|
||||
|
||||
/*
|
||||
* buf_mapped - relay buffer mmap notification
|
||||
* @buf: the channel buffer
|
||||
* @filp: relay file pointer
|
||||
*
|
||||
* Called when a relay file is successfully mmapped
|
||||
*/
|
||||
void (*buf_mapped)(struct rchan_buf *buf,
|
||||
struct file *filp);
|
||||
|
||||
/*
|
||||
* buf_unmapped - relay buffer unmap notification
|
||||
* @buf: the channel buffer
|
||||
* @filp: relay file pointer
|
||||
*
|
||||
* Called when a relay file is successfully unmapped
|
||||
*/
|
||||
void (*buf_unmapped)(struct rchan_buf *buf,
|
||||
struct file *filp);
|
||||
/*
|
||||
* create_buf_file - create file to represent a relay channel buffer
|
||||
* @filename: the name of the file to create
|
||||
* @parent: the parent of the file to create
|
||||
* @mode: the mode of the file to create
|
||||
* @buf: the channel buffer
|
||||
* @is_global: outparam - set non-zero if the buffer should be global
|
||||
*
|
||||
* Called during relay_open(), once for each per-cpu buffer,
|
||||
* to allow the client to create a file to be used to
|
||||
* represent the corresponding channel buffer. If the file is
|
||||
* created outside of relay, the parent must also exist in
|
||||
* that filesystem.
|
||||
*
|
||||
* The callback should return the dentry of the file created
|
||||
* to represent the relay buffer.
|
||||
*
|
||||
* Setting the is_global outparam to a non-zero value will
|
||||
* cause relay_open() to create a single global buffer rather
|
||||
* than the default set of per-cpu buffers.
|
||||
*
|
||||
* See Documentation/filesystems/relayfs.txt for more info.
|
||||
*/
|
||||
struct dentry *(*create_buf_file)(const char *filename,
|
||||
struct dentry *parent,
|
||||
int mode,
|
||||
struct rchan_buf *buf,
|
||||
int *is_global);
|
||||
|
||||
/*
|
||||
* remove_buf_file - remove file representing a relay channel buffer
|
||||
* @dentry: the dentry of the file to remove
|
||||
*
|
||||
* Called during relay_close(), once for each per-cpu buffer,
|
||||
* to allow the client to remove a file used to represent a
|
||||
* channel buffer.
|
||||
*
|
||||
* The callback should return 0 if successful, negative if not.
|
||||
*/
|
||||
int (*remove_buf_file)(struct dentry *dentry);
|
||||
};
|
||||
|
||||
/*
|
||||
* CONFIG_RELAY kernel API, kernel/relay.c
|
||||
*/
|
||||
|
||||
struct rchan *relay_open(const char *base_filename,
|
||||
struct dentry *parent,
|
||||
size_t subbuf_size,
|
||||
size_t n_subbufs,
|
||||
struct rchan_callbacks *cb);
|
||||
extern void relay_close(struct rchan *chan);
|
||||
extern void relay_flush(struct rchan *chan);
|
||||
extern void relay_subbufs_consumed(struct rchan *chan,
|
||||
unsigned int cpu,
|
||||
size_t consumed);
|
||||
extern void relay_reset(struct rchan *chan);
|
||||
extern int relay_buf_full(struct rchan_buf *buf);
|
||||
|
||||
extern size_t relay_switch_subbuf(struct rchan_buf *buf,
|
||||
size_t length);
|
||||
|
||||
/**
|
||||
* relay_write - write data into the channel
|
||||
* @chan: relay channel
|
||||
* @data: data to be written
|
||||
* @length: number of bytes to write
|
||||
*
|
||||
* Writes data into the current cpu's channel buffer.
|
||||
*
|
||||
* Protects the buffer by disabling interrupts. Use this
|
||||
* if you might be logging from interrupt context. Try
|
||||
* __relay_write() if you know you won't be logging from
|
||||
* interrupt context.
|
||||
*/
|
||||
static inline void relay_write(struct rchan *chan,
|
||||
const void *data,
|
||||
size_t length)
|
||||
{
|
||||
unsigned long flags;
|
||||
struct rchan_buf *buf;
|
||||
|
||||
local_irq_save(flags);
|
||||
buf = chan->buf[smp_processor_id()];
|
||||
if (unlikely(buf->offset + length > chan->subbuf_size))
|
||||
length = relay_switch_subbuf(buf, length);
|
||||
memcpy(buf->data + buf->offset, data, length);
|
||||
buf->offset += length;
|
||||
local_irq_restore(flags);
|
||||
}
|
||||
|
||||
/**
|
||||
* __relay_write - write data into the channel
|
||||
* @chan: relay channel
|
||||
* @data: data to be written
|
||||
* @length: number of bytes to write
|
||||
*
|
||||
* Writes data into the current cpu's channel buffer.
|
||||
*
|
||||
* Protects the buffer by disabling preemption. Use
|
||||
* relay_write() if you might be logging from interrupt
|
||||
* context.
|
||||
*/
|
||||
static inline void __relay_write(struct rchan *chan,
|
||||
const void *data,
|
||||
size_t length)
|
||||
{
|
||||
struct rchan_buf *buf;
|
||||
|
||||
buf = chan->buf[get_cpu()];
|
||||
if (unlikely(buf->offset + length > buf->chan->subbuf_size))
|
||||
length = relay_switch_subbuf(buf, length);
|
||||
memcpy(buf->data + buf->offset, data, length);
|
||||
buf->offset += length;
|
||||
put_cpu();
|
||||
}
|
||||
|
||||
/**
|
||||
* relay_reserve - reserve slot in channel buffer
|
||||
* @chan: relay channel
|
||||
* @length: number of bytes to reserve
|
||||
*
|
||||
* Returns pointer to reserved slot, NULL if full.
|
||||
*
|
||||
* Reserves a slot in the current cpu's channel buffer.
|
||||
* Does not protect the buffer at all - caller must provide
|
||||
* appropriate synchronization.
|
||||
*/
|
||||
static inline void *relay_reserve(struct rchan *chan, size_t length)
|
||||
{
|
||||
void *reserved;
|
||||
struct rchan_buf *buf = chan->buf[smp_processor_id()];
|
||||
|
||||
if (unlikely(buf->offset + length > buf->chan->subbuf_size)) {
|
||||
length = relay_switch_subbuf(buf, length);
|
||||
if (!length)
|
||||
return NULL;
|
||||
}
|
||||
reserved = buf->data + buf->offset;
|
||||
buf->offset += length;
|
||||
|
||||
return reserved;
|
||||
}
|
||||
|
||||
/**
|
||||
* subbuf_start_reserve - reserve bytes at the start of a sub-buffer
|
||||
* @buf: relay channel buffer
|
||||
* @length: number of bytes to reserve
|
||||
*
|
||||
* Helper function used to reserve bytes at the beginning of
|
||||
* a sub-buffer in the subbuf_start() callback.
|
||||
*/
|
||||
static inline void subbuf_start_reserve(struct rchan_buf *buf,
|
||||
size_t length)
|
||||
{
|
||||
BUG_ON(length >= buf->chan->subbuf_size - 1);
|
||||
buf->offset = length;
|
||||
}
|
||||
|
||||
/*
|
||||
* exported relay file operations, kernel/relay.c
|
||||
*/
|
||||
extern struct file_operations relay_file_operations;
|
||||
|
||||
#endif /* _LINUX_RELAY_H */
|
||||
|
@ -706,6 +706,7 @@ struct task_struct {
|
||||
prio_array_t *array;
|
||||
|
||||
unsigned short ioprio;
|
||||
unsigned int btrace_seq;
|
||||
|
||||
unsigned long sleep_avg;
|
||||
unsigned long long timestamp, last_ran;
|
||||
|
11
init/Kconfig
11
init/Kconfig
@ -214,6 +214,17 @@ config CPUSETS
|
||||
|
||||
Say N if unsure.
|
||||
|
||||
config RELAY
|
||||
bool "Kernel->user space relay support (formerly relayfs)"
|
||||
help
|
||||
This option enables support for relay interface support in
|
||||
certain file systems (such as debugfs).
|
||||
It is designed to provide an efficient mechanism for tools and
|
||||
facilities to relay large amounts of data from kernel space to
|
||||
user space.
|
||||
|
||||
If unsure, say N.
|
||||
|
||||
source "usr/Kconfig"
|
||||
|
||||
config UID16
|
||||
|
@ -34,6 +34,7 @@ obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o
|
||||
obj-$(CONFIG_GENERIC_HARDIRQS) += irq/
|
||||
obj-$(CONFIG_SECCOMP) += seccomp.o
|
||||
obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o
|
||||
obj-$(CONFIG_RELAY) += relay.o
|
||||
|
||||
ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y)
|
||||
# According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
|
||||
|
@ -181,6 +181,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
|
||||
/* One for us, one for whoever does the "release_task()" (usually parent) */
|
||||
atomic_set(&tsk->usage,2);
|
||||
atomic_set(&tsk->fs_excl, 0);
|
||||
tsk->btrace_seq = 0;
|
||||
return tsk;
|
||||
}
|
||||
|
||||
|
1012
kernel/relay.c
Normal file
1012
kernel/relay.c
Normal file
File diff suppressed because it is too large
Load Diff
@ -26,6 +26,7 @@
|
||||
#include <linux/init.h>
|
||||
#include <linux/hash.h>
|
||||
#include <linux/highmem.h>
|
||||
#include <linux/blktrace_api.h>
|
||||
#include <asm/tlbflush.h>
|
||||
|
||||
static mempool_t *page_pool, *isa_page_pool;
|
||||
@ -483,6 +484,8 @@ void blk_queue_bounce(request_queue_t *q, struct bio **bio_orig)
|
||||
pool = isa_page_pool;
|
||||
}
|
||||
|
||||
blk_add_trace_bio(q, *bio_orig, BLK_TA_BOUNCE);
|
||||
|
||||
/*
|
||||
* slow path
|
||||
*/
|
||||
|
Loading…
Reference in New Issue
Block a user