diff options
| -rw-r--r-- | block/Kconfig | 12 | ||||
| -rw-r--r-- | block/Makefile | 2 | ||||
| -rw-r--r-- | block/blktrace.c | 538 | ||||
| -rw-r--r-- | block/elevator.c | 4 | ||||
| -rw-r--r-- | block/ioctl.c | 6 | ||||
| -rw-r--r-- | block/ll_rw_blk.c | 44 | ||||
| -rw-r--r-- | drivers/block/cciss.c | 2 | ||||
| -rw-r--r-- | drivers/md/dm.c | 13 | ||||
| -rw-r--r-- | fs/Kconfig | 12 | ||||
| -rw-r--r-- | fs/Makefile | 1 | ||||
| -rw-r--r-- | fs/bio.c | 4 | ||||
| -rw-r--r-- | fs/compat_ioctl.c | 1 | ||||
| -rw-r--r-- | fs/relayfs/Makefile | 4 | ||||
| -rw-r--r-- | fs/relayfs/buffers.c | 190 | ||||
| -rw-r--r-- | fs/relayfs/buffers.h | 12 | ||||
| -rw-r--r-- | fs/relayfs/inode.c | 581 | ||||
| -rw-r--r-- | fs/relayfs/relay.c | 482 | ||||
| -rw-r--r-- | fs/relayfs/relay.h | 8 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 3 | ||||
| -rw-r--r-- | include/linux/blktrace_api.h | 277 | ||||
| -rw-r--r-- | include/linux/compat_ioctl.h | 4 | ||||
| -rw-r--r-- | include/linux/fs.h | 4 | ||||
| -rw-r--r-- | include/linux/relay.h | 281 | ||||
| -rw-r--r-- | include/linux/sched.h | 1 | ||||
| -rw-r--r-- | init/Kconfig | 11 | ||||
| -rw-r--r-- | kernel/Makefile | 1 | ||||
| -rw-r--r-- | kernel/fork.c | 1 | ||||
| -rw-r--r-- | kernel/relay.c | 1012 | ||||
| -rw-r--r-- | mm/highmem.c | 3 |
29 files changed, 2221 insertions, 1293 deletions
diff --git a/block/Kconfig b/block/Kconfig index 377f6dd20e17..96783645092d 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -11,4 +11,16 @@ config LBD your machine, or if you want to have a raid or loopback device bigger than 2TB. Otherwise say N. +config BLK_DEV_IO_TRACE + bool "Support for tracing block io actions" + select RELAY + select DEBUG_FS + help + Say Y here, if you want to be able to trace the block layer actions + on a given queue. Tracing allows you to see any traffic happening + on a block device queue. For more information (and the user space + support tools needed), fetch the blktrace app from: + + git://brick.kernel.dk/data/git/blktrace.git + source block/Kconfig.iosched diff --git a/block/Makefile b/block/Makefile index 7e4f93e2b44e..c05de0e0037f 100644 --- a/block/Makefile +++ b/block/Makefile @@ -8,3 +8,5 @@ obj-$(CONFIG_IOSCHED_NOOP) += noop-iosched.o obj-$(CONFIG_IOSCHED_AS) += as-iosched.o obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o + +obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o diff --git a/block/blktrace.c b/block/blktrace.c new file mode 100644 index 000000000000..36f3a172275f --- /dev/null +++ b/block/blktrace.c @@ -0,0 +1,538 @@ +/* + * Copyright (C) 2006 Jens Axboe <axboe@suse.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + */ +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/blkdev.h> +#include <linux/blktrace_api.h> +#include <linux/percpu.h> +#include <linux/init.h> +#include <linux/mutex.h> +#include <linux/debugfs.h> +#include <asm/uaccess.h> + +static DEFINE_PER_CPU(unsigned long long, blk_trace_cpu_offset) = { 0, }; +static unsigned int blktrace_seq __read_mostly = 1; + +/* + * Send out a notify for this process, if we haven't done so since a trace + * started + */ +static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) +{ + struct blk_io_trace *t; + + t = relay_reserve(bt->rchan, sizeof(*t) + sizeof(tsk->comm)); + if (t) { + t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; + t->device = bt->dev; + t->action = BLK_TC_ACT(BLK_TC_NOTIFY); + t->pid = tsk->pid; + t->cpu = smp_processor_id(); + t->pdu_len = sizeof(tsk->comm); + memcpy((void *) t + sizeof(*t), tsk->comm, t->pdu_len); + tsk->btrace_seq = blktrace_seq; + } +} + +static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, + pid_t pid) +{ + if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) + return 1; + if (sector < bt->start_lba || sector > bt->end_lba) + return 1; + if (bt->pid && pid != bt->pid) + return 1; + + return 0; +} + +/* + * Data direction bit lookup + */ +static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK_TC_WRITE) }; + +/* + * Bio action bits of interest + */ +static u32 bio_act[3] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_ACT(BLK_TC_SYNC) }; + +/* + * More could be added as needed, taking care to increment the decrementer + * to get correct indexing + */ +#define trace_barrier_bit(rw) \ + (((rw) & (1 << BIO_RW_BARRIER)) >> (BIO_RW_BARRIER - 0)) +#define trace_sync_bit(rw) \ + (((rw) & (1 << BIO_RW_SYNC)) >> (BIO_RW_SYNC - 1)) + +/* + * The worker for the various blk_add_trace*() types. Fills out a + * blk_io_trace structure and places it in a per-cpu subbuffer. + */ +void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, + int rw, u32 what, int error, int pdu_len, void *pdu_data) +{ + struct task_struct *tsk = current; + struct blk_io_trace *t; + unsigned long flags; + unsigned long *sequence; + pid_t pid; + int cpu; + + if (unlikely(bt->trace_state != Blktrace_running)) + return; + + what |= ddir_act[rw & WRITE]; + what |= bio_act[trace_barrier_bit(rw)]; + what |= bio_act[trace_sync_bit(rw)]; + + pid = tsk->pid; + if (unlikely(act_log_check(bt, what, sector, pid))) + return; + + /* + * A word about the locking here - we disable interrupts to reserve + * some space in the relay per-cpu buffer, to prevent an irq + * from coming in and stepping on our toes. Once reserved, it's + * enough to get preemption disabled to prevent read of this data + * before we are through filling it. get_cpu()/put_cpu() does this + * for us + */ + local_irq_save(flags); + + if (unlikely(tsk->btrace_seq != blktrace_seq)) + trace_note_tsk(bt, tsk); + + t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); + if (t) { + cpu = smp_processor_id(); + sequence = per_cpu_ptr(bt->sequence, cpu); + + t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; + t->sequence = ++(*sequence); + t->time = sched_clock() - per_cpu(blk_trace_cpu_offset, cpu); + t->sector = sector; + t->bytes = bytes; + t->action = what; + t->pid = pid; + t->device = bt->dev; + t->cpu = cpu; + t->error = error; + t->pdu_len = pdu_len; + + if (pdu_len) + memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); + } + + local_irq_restore(flags); +} + +EXPORT_SYMBOL_GPL(__blk_add_trace); + +static struct dentry *blk_tree_root; +static struct mutex blk_tree_mutex; +static unsigned int root_users; + +static inline void blk_remove_root(void) +{ + if (blk_tree_root) { + debugfs_remove(blk_tree_root); + blk_tree_root = NULL; + } +} + +static void blk_remove_tree(struct dentry *dir) +{ + mutex_lock(&blk_tree_mutex); + debugfs_remove(dir); + if (--root_users == 0) + blk_remove_root(); + mutex_unlock(&blk_tree_mutex); +} + +static struct dentry *blk_create_tree(const char *blk_name) +{ + struct dentry *dir = NULL; + + mutex_lock(&blk_tree_mutex); + + if (!blk_tree_root) { + blk_tree_root = debugfs_create_dir("block", NULL); + if (!blk_tree_root) + goto err; + } + + dir = debugfs_create_dir(blk_name, blk_tree_root); + if (dir) + root_users++; + else + blk_remove_root(); + +err: + mutex_unlock(&blk_tree_mutex); + return dir; +} + +static void blk_trace_cleanup(struct blk_trace *bt) +{ + relay_close(bt->rchan); + debugfs_remove(bt->dropped_file); + blk_remove_tree(bt->dir); + free_percpu(bt->sequence); + kfree(bt); +} + +static int blk_trace_remove(request_queue_t *q) +{ + struct blk_trace *bt; + + bt = xchg(&q->blk_trace, NULL); + if (!bt) + return -EINVAL; + + if (bt->trace_state == Blktrace_setup || + bt->trace_state == Blktrace_stopped) + blk_trace_cleanup(bt); + + return 0; +} + +static int blk_dropped_open(struct inode *inode, struct file *filp) +{ + filp->private_data = inode->u.generic_ip; + + return 0; +} + +static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, + size_t count, loff_t *ppos) +{ + struct blk_trace *bt = filp->private_data; + char buf[16]; + + snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); + + return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); +} + +static struct file_operations blk_dropped_fops = { + .owner = THIS_MODULE, + .open = blk_dropped_open, + .read = blk_dropped_read, +}; + +/* + * Keep track of how many times we encountered a full subbuffer, to aid + * the user space app in telling how many lost events there were. + */ +static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, + void *prev_subbuf, size_t prev_padding) +{ + struct blk_trace *bt; + + if (!relay_buf_full(buf)) + return 1; + + bt = buf->chan->private_data; + atomic_inc(&bt->dropped); + return 0; +} + +static int blk_remove_buf_file_callback(struct dentry *dentry) +{ + debugfs_remove(dentry); + return 0; +} + +static struct dentry *blk_create_buf_file_callback(const char *filename, + struct dentry *parent, + 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); + diff --git a/block/elevator.c b/block/elevator.c index db3d0d8296a0..5e558c4689a4 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -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) { diff --git a/block/ioctl.c b/block/ioctl.c index 35fdb7dc6512..9cfa2e1ecb24 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -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; } diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index 6c793b196aa9..062067fa7ead 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -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 @@ rq_starved: 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 @@ end_io: */ 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 */ diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c index e29b8926f80e..1f2890989b56 100644 --- a/drivers/block/cciss.c +++ b/drivers/block/cciss.c @@ -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); } diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 26b08ee425c7..8c82373f7ff3 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -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 */ diff --git a/fs/Kconfig b/fs/Kconfig index e9749b0eecd8..c8d0a209120c 100644 --- a/fs/Kconfig +++ b/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 diff --git a/fs/Makefile b/fs/Makefile index 1db711319c80..080b3867be4d 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -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-$(CONFIG_XFS_FS) += xfs/ @@ -25,6 +25,7 @@ #include <linux/module.h> #include <linux/mempool.h> #include <linux/workqueue.h> +#include <linux/blktrace_api.h> #include <scsi/sg.h> /* for struct sg_iovec */ #define BIO_POOL_SIZE 256 @@ -1095,6 +1096,9 @@ struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors) if (!bp) return bp; + blk_add_trace_pdu_int(bdev_get_queue(bi->bi_bdev), BLK_TA_SPLIT, bi, + bi->bi_sector + first_sectors); + BUG_ON(bi->bi_vcnt != 1); BUG_ON(bi->bi_idx != 0); atomic_set(&bp->cnt, 3); diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c index c666769a875d..7c031f00fd79 100644 --- a/fs/compat_ioctl.c +++ b/fs/compat_ioctl.c @@ -72,6 +72,7 @@ #include <linux/i2c-dev.h> #include <linux/wireless.h> #include <linux/atalk.h> +#include <linux/blktrace_api.h> #include <net/sock.h> /* siocdevprivate_ioctl */ #include <net/bluetooth/bluetooth.h> diff --git a/fs/relayfs/Makefile b/fs/relayfs/Makefile deleted file mode 100644 index e76e182cdb38..000000000000 --- a/fs/relayfs/Makefile +++ /dev/null @@ -1,4 +0,0 @@ -obj-$(CONFIG_RELAYFS_FS) += relayfs.o - -relayfs-y := relay.o inode.o buffers.o - diff --git a/fs/relayfs/buffers.c b/fs/relayfs/buffers.c deleted file mode 100644 index 10187812771e..000000000000 --- a/fs/relayfs/buffers.c +++ /dev/null @@ -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); -} diff --git a/fs/relayfs/buffers.h b/fs/relayfs/buffers.h deleted file mode 100644 index 37a12493f641..000000000000 --- a/fs/relayfs/buffers.h +++ /dev/null @@ -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 */ diff --git a/fs/relayfs/inode.c b/fs/relayfs/inode.c deleted file mode 100644 index 383523011aad..000000000000 --- a/fs/relayfs/inode.c +++ /dev/null @@ -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"); - diff --git a/fs/relayfs/relay.c b/fs/relayfs/relay.c deleted file mode 100644 index abf3ceaace49..000000000000 --- a/fs/relayfs/relay.c +++ /dev/null @@ -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); diff --git a/fs/relayfs/relay.h b/fs/relayfs/relay.h deleted file mode 100644 index 0993d3e5753b..000000000000 --- a/fs/relayfs/relay.h +++ /dev/null @@ -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 */ diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 56bb6a4e15f3..c179966f1a2f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.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 */ diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h new file mode 100644 index 000000000000..b34d3e73d5ea --- /dev/null +++ b/include/linux/blktrace_api.h @@ -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 diff --git a/include/linux/compat_ioctl.h b/include/linux/compat_ioctl.h index ae7dfb790df3..efb518f16bb3 100644 --- a/include/linux/compat_ioctl.h +++ b/include/linux/compat_ioctl.h @@ -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 */ diff --git a/include/linux/fs.h b/include/linux/fs.h index f9c9dea636d0..9b34a1b03455 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -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 */ diff --git a/include/linux/relay.h b/include/linux/relay.h new file mode 100644 index 000000000000..4bcc1531d6a9 --- /dev/null +++ b/include/linux/relay.h @@ -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 */ + diff --git a/include/linux/sched.h b/include/linux/sched.h index 62e6314382f0..e60a91d5b369 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.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; diff --git a/init/Kconfig b/init/Kconfig index 38416a199def..1d19fd25204b 100644 --- a/init/Kconfig +++ b/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 diff --git a/kernel/Makefile b/kernel/Makefile index 4ae0fbde815d..aebd7a78984e 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -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 diff --git a/kernel/fork.c b/kernel/fork.c index c79ae0b19a49..c21bae8c93b9 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -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; } diff --git a/kernel/relay.c b/kernel/relay.c new file mode 100644 index 000000000000..33345e73485c --- /dev/null +++ b/kernel/relay.c @@ -0,0 +1,1012 @@ +/* + * Public API and common code for kernel->userspace relay file support. + * + * 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) + * + * Moved to kernel/relay.c by Paul Mundt, 2006. + * + * 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/relay.h> +#include <linux/vmalloc.h> +#include <linux/mm.h> + +/* + * close() vm_op implementation for relay 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 relay 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. The + * passed in size will get page aligned, if it isn't already. + */ +static void *relay_alloc_buf(struct rchan_buf *buf, size_t *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_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_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 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); +} + +/** + * 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; +} +EXPORT_SYMBOL_GPL(relay_buf_empty); + +/** + * 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; +} +EXPORT_SYMBOL_GPL(relay_buf_full); + +/* + * High-level relay 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. Does nothing. + */ +static struct dentry *create_buf_file_default_callback(const char *filename, + struct dentry *parent, + int mode, + struct rchan_buf *buf, + int *is_global) +{ + return NULL; +} + +/* + * remove_buf_file() default callback. Does nothing. + */ +static int remove_buf_file_default_callback(struct dentry *dentry) +{ + return -EINVAL; +} + +/* 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]; + } +} +EXPORT_SYMBOL_GPL(relay_reset); + +/** + * relay_open_buf - create a new relay channel buffer + * + * 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; + 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 relay 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); + if (!chan->buf[i]) + goto free_bufs; + + chan->buf[i]->cpu = i; + } + + 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; +} +EXPORT_SYMBOL_GPL(relay_open); + +/** + * 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++; + buf->dentry->d_inode->i_size += buf->chan->subbuf_size - + buf->padding[old_subbuf]; + smp_mb(); + 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; +} +EXPORT_SYMBOL_GPL(relay_switch_subbuf); + +/** + * 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; +} +EXPORT_SYMBOL_GPL(relay_subbufs_consumed); + +/** + * 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 "relay: 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); +} +EXPORT_SYMBOL_GPL(relay_close); + +/** + * 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_flush); + +/** + * 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 subbuf_size = buf->chan->subbuf_size; + size_t n_subbufs = buf->chan->n_subbufs; + size_t produced = buf->subbufs_produced; + size_t consumed = buf->subbufs_consumed; + + relay_file_read_consume(buf, read_pos, 0); + + if (unlikely(buf->offset > subbuf_size)) { + if (produced == consumed) + return 0; + return 1; + } + + if (unlikely(produced - consumed >= n_subbufs)) { + consumed = (produced / n_subbufs) * n_subbufs; + buf->subbufs_consumed = consumed; + } + + produced = (produced % n_subbufs) * subbuf_size + buf->offset; + consumed = (consumed % n_subbufs) * subbuf_size + buf->bytes_consumed; + + if (consumed > produced) + produced += n_subbufs * subbuf_size; + + if (consumed == produced) + return 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; +} + +/** + * subbuf_read_actor - read up to one subbuf's worth of data + */ +static int subbuf_read_actor(size_t read_start, + struct rchan_buf *buf, + size_t avail, + read_descriptor_t *desc, + read_actor_t actor) +{ + void *from; + int ret = 0; + + from = buf->start + read_start; + ret = avail; + if (copy_to_user(desc->arg.data, from, avail)) { + desc->error = -EFAULT; + ret = 0; + } + desc->arg.data += ret; + desc->written += ret; + desc->count -= ret; + + return ret; +} + +/** + * subbuf_send_actor - send up to one subbuf's worth of data + */ +static int subbuf_send_actor(size_t read_start, + struct rchan_buf *buf, + size_t avail, + read_descriptor_t *desc, + read_actor_t actor) +{ + unsigned long pidx, poff; + unsigned int subbuf_pages; + int ret = 0; + + subbuf_pages = buf->chan->alloc_size >> PAGE_SHIFT; + pidx = (read_start / PAGE_SIZE) % subbuf_pages; + poff = read_start & ~PAGE_MASK; + while (avail) { + struct page *p = buf->page_array[pidx]; + unsigned int len; + + len = PAGE_SIZE - poff; + if (len > avail) + len = avail; + + len = actor(desc, p, poff, len); + if (desc->error) + break; + + avail -= len; + ret += len; + poff = 0; + pidx = (pidx + 1) % subbuf_pages; + } + + return ret; +} + +typedef int (*subbuf_actor_t) (size_t read_start, + struct rchan_buf *buf, + size_t avail, + read_descriptor_t *desc, + read_actor_t actor); + +/** + * relay_file_read_subbufs - read count bytes, bridging subbuf boundaries + */ +static inline ssize_t relay_file_read_subbufs(struct file *filp, + loff_t *ppos, + size_t count, + subbuf_actor_t subbuf_actor, + read_actor_t actor, + void *target) +{ + struct rchan_buf *buf = filp->private_data; + size_t read_start, avail; + read_descriptor_t desc; + int ret; + + if (!count) + return 0; + + desc.written = 0; + desc.count = count; + desc.arg.data = target; + desc.error = 0; + + mutex_lock(&filp->f_dentry->d_inode->i_mutex); + do { + if (!relay_file_read_avail(buf, *ppos)) + break; + + read_start = relay_file_read_start_pos(*ppos, buf); + avail = relay_file_read_subbuf_avail(read_start, buf); + if (!avail) + break; + + avail = min(desc.count, avail); + ret = subbuf_actor(read_start, buf, avail, &desc, actor); + if (desc.error < 0) + break; + + if (ret) { + relay_file_read_consume(buf, read_start, ret); + *ppos = relay_file_read_end_pos(buf, read_start, ret); + } + } while (desc.count && ret); + mutex_unlock(&filp->f_dentry->d_inode->i_mutex); + + return desc.written; +} + +static ssize_t relay_file_read(struct file *filp, + char __user *buffer, + size_t count, + loff_t *ppos) +{ + return relay_file_read_subbufs(filp, ppos, count, subbuf_read_actor, + NULL, buffer); +} + +static ssize_t relay_file_sendfile(struct file *filp, + loff_t *ppos, + size_t count, + read_actor_t actor, + void *target) +{ + return relay_file_read_subbufs(filp, ppos, count, subbuf_send_actor, + actor, target); +} + +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, + .sendfile = relay_file_sendfile, +}; +EXPORT_SYMBOL_GPL(relay_file_operations); diff --git a/mm/highmem.c b/mm/highmem.c index ce2e7e8bbfa7..d0ea1eec6a9a 100644 --- a/mm/highmem.c +++ b/mm/highmem.c @@ -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 */ |