mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-28 20:02:17 +00:00
![Kent Overstreet](/assets/img/avatar_default.png)
Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
447 lines
9.9 KiB
C
447 lines
9.9 KiB
C
/*
|
|
* Copyright (C) 2003 Sistina Software (UK) Limited.
|
|
* Copyright (C) 2004, 2010-2011 Red Hat, Inc. All rights reserved.
|
|
*
|
|
* This file is released under the GPL.
|
|
*/
|
|
|
|
#include <linux/device-mapper.h>
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/blkdev.h>
|
|
#include <linux/bio.h>
|
|
#include <linux/slab.h>
|
|
|
|
#define DM_MSG_PREFIX "flakey"
|
|
|
|
#define all_corrupt_bio_flags_match(bio, fc) \
|
|
(((bio)->bi_rw & (fc)->corrupt_bio_flags) == (fc)->corrupt_bio_flags)
|
|
|
|
/*
|
|
* Flakey: Used for testing only, simulates intermittent,
|
|
* catastrophic device failure.
|
|
*/
|
|
struct flakey_c {
|
|
struct dm_dev *dev;
|
|
unsigned long start_time;
|
|
sector_t start;
|
|
unsigned up_interval;
|
|
unsigned down_interval;
|
|
unsigned long flags;
|
|
unsigned corrupt_bio_byte;
|
|
unsigned corrupt_bio_rw;
|
|
unsigned corrupt_bio_value;
|
|
unsigned corrupt_bio_flags;
|
|
};
|
|
|
|
enum feature_flag_bits {
|
|
DROP_WRITES
|
|
};
|
|
|
|
struct per_bio_data {
|
|
bool bio_submitted;
|
|
};
|
|
|
|
static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
|
|
struct dm_target *ti)
|
|
{
|
|
int r;
|
|
unsigned argc;
|
|
const char *arg_name;
|
|
|
|
static struct dm_arg _args[] = {
|
|
{0, 6, "Invalid number of feature args"},
|
|
{1, UINT_MAX, "Invalid corrupt bio byte"},
|
|
{0, 255, "Invalid corrupt value to write into bio byte (0-255)"},
|
|
{0, UINT_MAX, "Invalid corrupt bio flags mask"},
|
|
};
|
|
|
|
/* No feature arguments supplied. */
|
|
if (!as->argc)
|
|
return 0;
|
|
|
|
r = dm_read_arg_group(_args, as, &argc, &ti->error);
|
|
if (r)
|
|
return r;
|
|
|
|
while (argc) {
|
|
arg_name = dm_shift_arg(as);
|
|
argc--;
|
|
|
|
/*
|
|
* drop_writes
|
|
*/
|
|
if (!strcasecmp(arg_name, "drop_writes")) {
|
|
if (test_and_set_bit(DROP_WRITES, &fc->flags)) {
|
|
ti->error = "Feature drop_writes duplicated";
|
|
return -EINVAL;
|
|
}
|
|
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags>
|
|
*/
|
|
if (!strcasecmp(arg_name, "corrupt_bio_byte")) {
|
|
if (!argc) {
|
|
ti->error = "Feature corrupt_bio_byte requires parameters";
|
|
return -EINVAL;
|
|
}
|
|
|
|
r = dm_read_arg(_args + 1, as, &fc->corrupt_bio_byte, &ti->error);
|
|
if (r)
|
|
return r;
|
|
argc--;
|
|
|
|
/*
|
|
* Direction r or w?
|
|
*/
|
|
arg_name = dm_shift_arg(as);
|
|
if (!strcasecmp(arg_name, "w"))
|
|
fc->corrupt_bio_rw = WRITE;
|
|
else if (!strcasecmp(arg_name, "r"))
|
|
fc->corrupt_bio_rw = READ;
|
|
else {
|
|
ti->error = "Invalid corrupt bio direction (r or w)";
|
|
return -EINVAL;
|
|
}
|
|
argc--;
|
|
|
|
/*
|
|
* Value of byte (0-255) to write in place of correct one.
|
|
*/
|
|
r = dm_read_arg(_args + 2, as, &fc->corrupt_bio_value, &ti->error);
|
|
if (r)
|
|
return r;
|
|
argc--;
|
|
|
|
/*
|
|
* Only corrupt bios with these flags set.
|
|
*/
|
|
r = dm_read_arg(_args + 3, as, &fc->corrupt_bio_flags, &ti->error);
|
|
if (r)
|
|
return r;
|
|
argc--;
|
|
|
|
continue;
|
|
}
|
|
|
|
ti->error = "Unrecognised flakey feature requested";
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (test_bit(DROP_WRITES, &fc->flags) && (fc->corrupt_bio_rw == WRITE)) {
|
|
ti->error = "drop_writes is incompatible with corrupt_bio_byte with the WRITE flag set";
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Construct a flakey mapping:
|
|
* <dev_path> <offset> <up interval> <down interval> [<#feature args> [<arg>]*]
|
|
*
|
|
* Feature args:
|
|
* [drop_writes]
|
|
* [corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags>]
|
|
*
|
|
* Nth_byte starts from 1 for the first byte.
|
|
* Direction is r for READ or w for WRITE.
|
|
* bio_flags is ignored if 0.
|
|
*/
|
|
static int flakey_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
|
{
|
|
static struct dm_arg _args[] = {
|
|
{0, UINT_MAX, "Invalid up interval"},
|
|
{0, UINT_MAX, "Invalid down interval"},
|
|
};
|
|
|
|
int r;
|
|
struct flakey_c *fc;
|
|
unsigned long long tmpll;
|
|
struct dm_arg_set as;
|
|
const char *devname;
|
|
char dummy;
|
|
|
|
as.argc = argc;
|
|
as.argv = argv;
|
|
|
|
if (argc < 4) {
|
|
ti->error = "Invalid argument count";
|
|
return -EINVAL;
|
|
}
|
|
|
|
fc = kzalloc(sizeof(*fc), GFP_KERNEL);
|
|
if (!fc) {
|
|
ti->error = "Cannot allocate context";
|
|
return -ENOMEM;
|
|
}
|
|
fc->start_time = jiffies;
|
|
|
|
devname = dm_shift_arg(&as);
|
|
|
|
if (sscanf(dm_shift_arg(&as), "%llu%c", &tmpll, &dummy) != 1) {
|
|
ti->error = "Invalid device sector";
|
|
goto bad;
|
|
}
|
|
fc->start = tmpll;
|
|
|
|
r = dm_read_arg(_args, &as, &fc->up_interval, &ti->error);
|
|
if (r)
|
|
goto bad;
|
|
|
|
r = dm_read_arg(_args, &as, &fc->down_interval, &ti->error);
|
|
if (r)
|
|
goto bad;
|
|
|
|
if (!(fc->up_interval + fc->down_interval)) {
|
|
ti->error = "Total (up + down) interval is zero";
|
|
goto bad;
|
|
}
|
|
|
|
if (fc->up_interval + fc->down_interval < fc->up_interval) {
|
|
ti->error = "Interval overflow";
|
|
goto bad;
|
|
}
|
|
|
|
r = parse_features(&as, fc, ti);
|
|
if (r)
|
|
goto bad;
|
|
|
|
if (dm_get_device(ti, devname, dm_table_get_mode(ti->table), &fc->dev)) {
|
|
ti->error = "Device lookup failed";
|
|
goto bad;
|
|
}
|
|
|
|
ti->num_flush_bios = 1;
|
|
ti->num_discard_bios = 1;
|
|
ti->per_bio_data_size = sizeof(struct per_bio_data);
|
|
ti->private = fc;
|
|
return 0;
|
|
|
|
bad:
|
|
kfree(fc);
|
|
return -EINVAL;
|
|
}
|
|
|
|
static void flakey_dtr(struct dm_target *ti)
|
|
{
|
|
struct flakey_c *fc = ti->private;
|
|
|
|
dm_put_device(ti, fc->dev);
|
|
kfree(fc);
|
|
}
|
|
|
|
static sector_t flakey_map_sector(struct dm_target *ti, sector_t bi_sector)
|
|
{
|
|
struct flakey_c *fc = ti->private;
|
|
|
|
return fc->start + dm_target_offset(ti, bi_sector);
|
|
}
|
|
|
|
static void flakey_map_bio(struct dm_target *ti, struct bio *bio)
|
|
{
|
|
struct flakey_c *fc = ti->private;
|
|
|
|
bio->bi_bdev = fc->dev->bdev;
|
|
if (bio_sectors(bio))
|
|
bio->bi_iter.bi_sector =
|
|
flakey_map_sector(ti, bio->bi_iter.bi_sector);
|
|
}
|
|
|
|
static void corrupt_bio_data(struct bio *bio, struct flakey_c *fc)
|
|
{
|
|
unsigned bio_bytes = bio_cur_bytes(bio);
|
|
char *data = bio_data(bio);
|
|
|
|
/*
|
|
* Overwrite the Nth byte of the data returned.
|
|
*/
|
|
if (data && bio_bytes >= fc->corrupt_bio_byte) {
|
|
data[fc->corrupt_bio_byte - 1] = fc->corrupt_bio_value;
|
|
|
|
DMDEBUG("Corrupting data bio=%p by writing %u to byte %u "
|
|
"(rw=%c bi_rw=%lu bi_sector=%llu cur_bytes=%u)\n",
|
|
bio, fc->corrupt_bio_value, fc->corrupt_bio_byte,
|
|
(bio_data_dir(bio) == WRITE) ? 'w' : 'r', bio->bi_rw,
|
|
(unsigned long long)bio->bi_iter.bi_sector, bio_bytes);
|
|
}
|
|
}
|
|
|
|
static int flakey_map(struct dm_target *ti, struct bio *bio)
|
|
{
|
|
struct flakey_c *fc = ti->private;
|
|
unsigned elapsed;
|
|
struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data));
|
|
pb->bio_submitted = false;
|
|
|
|
/* Are we alive ? */
|
|
elapsed = (jiffies - fc->start_time) / HZ;
|
|
if (elapsed % (fc->up_interval + fc->down_interval) >= fc->up_interval) {
|
|
/*
|
|
* Flag this bio as submitted while down.
|
|
*/
|
|
pb->bio_submitted = true;
|
|
|
|
/*
|
|
* Map reads as normal.
|
|
*/
|
|
if (bio_data_dir(bio) == READ)
|
|
goto map_bio;
|
|
|
|
/*
|
|
* Drop writes?
|
|
*/
|
|
if (test_bit(DROP_WRITES, &fc->flags)) {
|
|
bio_endio(bio, 0);
|
|
return DM_MAPIO_SUBMITTED;
|
|
}
|
|
|
|
/*
|
|
* Corrupt matching writes.
|
|
*/
|
|
if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == WRITE)) {
|
|
if (all_corrupt_bio_flags_match(bio, fc))
|
|
corrupt_bio_data(bio, fc);
|
|
goto map_bio;
|
|
}
|
|
|
|
/*
|
|
* By default, error all I/O.
|
|
*/
|
|
return -EIO;
|
|
}
|
|
|
|
map_bio:
|
|
flakey_map_bio(ti, bio);
|
|
|
|
return DM_MAPIO_REMAPPED;
|
|
}
|
|
|
|
static int flakey_end_io(struct dm_target *ti, struct bio *bio, int error)
|
|
{
|
|
struct flakey_c *fc = ti->private;
|
|
struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data));
|
|
|
|
/*
|
|
* Corrupt successful READs while in down state.
|
|
* If flags were specified, only corrupt those that match.
|
|
*/
|
|
if (fc->corrupt_bio_byte && !error && pb->bio_submitted &&
|
|
(bio_data_dir(bio) == READ) && (fc->corrupt_bio_rw == READ) &&
|
|
all_corrupt_bio_flags_match(bio, fc))
|
|
corrupt_bio_data(bio, fc);
|
|
|
|
return error;
|
|
}
|
|
|
|
static void flakey_status(struct dm_target *ti, status_type_t type,
|
|
unsigned status_flags, char *result, unsigned maxlen)
|
|
{
|
|
unsigned sz = 0;
|
|
struct flakey_c *fc = ti->private;
|
|
unsigned drop_writes;
|
|
|
|
switch (type) {
|
|
case STATUSTYPE_INFO:
|
|
result[0] = '\0';
|
|
break;
|
|
|
|
case STATUSTYPE_TABLE:
|
|
DMEMIT("%s %llu %u %u ", fc->dev->name,
|
|
(unsigned long long)fc->start, fc->up_interval,
|
|
fc->down_interval);
|
|
|
|
drop_writes = test_bit(DROP_WRITES, &fc->flags);
|
|
DMEMIT("%u ", drop_writes + (fc->corrupt_bio_byte > 0) * 5);
|
|
|
|
if (drop_writes)
|
|
DMEMIT("drop_writes ");
|
|
|
|
if (fc->corrupt_bio_byte)
|
|
DMEMIT("corrupt_bio_byte %u %c %u %u ",
|
|
fc->corrupt_bio_byte,
|
|
(fc->corrupt_bio_rw == WRITE) ? 'w' : 'r',
|
|
fc->corrupt_bio_value, fc->corrupt_bio_flags);
|
|
|
|
break;
|
|
}
|
|
}
|
|
|
|
static int flakey_ioctl(struct dm_target *ti, unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct flakey_c *fc = ti->private;
|
|
struct dm_dev *dev = fc->dev;
|
|
int r = 0;
|
|
|
|
/*
|
|
* Only pass ioctls through if the device sizes match exactly.
|
|
*/
|
|
if (fc->start ||
|
|
ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT)
|
|
r = scsi_verify_blk_ioctl(NULL, cmd);
|
|
|
|
return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg);
|
|
}
|
|
|
|
static int flakey_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
|
|
struct bio_vec *biovec, int max_size)
|
|
{
|
|
struct flakey_c *fc = ti->private;
|
|
struct request_queue *q = bdev_get_queue(fc->dev->bdev);
|
|
|
|
if (!q->merge_bvec_fn)
|
|
return max_size;
|
|
|
|
bvm->bi_bdev = fc->dev->bdev;
|
|
bvm->bi_sector = flakey_map_sector(ti, bvm->bi_sector);
|
|
|
|
return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
|
|
}
|
|
|
|
static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data)
|
|
{
|
|
struct flakey_c *fc = ti->private;
|
|
|
|
return fn(ti, fc->dev, fc->start, ti->len, data);
|
|
}
|
|
|
|
static struct target_type flakey_target = {
|
|
.name = "flakey",
|
|
.version = {1, 3, 1},
|
|
.module = THIS_MODULE,
|
|
.ctr = flakey_ctr,
|
|
.dtr = flakey_dtr,
|
|
.map = flakey_map,
|
|
.end_io = flakey_end_io,
|
|
.status = flakey_status,
|
|
.ioctl = flakey_ioctl,
|
|
.merge = flakey_merge,
|
|
.iterate_devices = flakey_iterate_devices,
|
|
};
|
|
|
|
static int __init dm_flakey_init(void)
|
|
{
|
|
int r = dm_register_target(&flakey_target);
|
|
|
|
if (r < 0)
|
|
DMERR("register failed %d", r);
|
|
|
|
return r;
|
|
}
|
|
|
|
static void __exit dm_flakey_exit(void)
|
|
{
|
|
dm_unregister_target(&flakey_target);
|
|
}
|
|
|
|
/* Module hooks */
|
|
module_init(dm_flakey_init);
|
|
module_exit(dm_flakey_exit);
|
|
|
|
MODULE_DESCRIPTION(DM_NAME " flakey target");
|
|
MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>");
|
|
MODULE_LICENSE("GPL");
|