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authorLinus Torvalds <torvalds@linux-foundation.org>2011-08-02 20:49:21 -1000
committerLinus Torvalds <torvalds@linux-foundation.org>2011-08-02 20:49:21 -1000
commitf3406816bb2486fc44558bec77179cd9bcbd4450 (patch)
tree718db1ef45e55314b5e7290f77e70e6328d855a4
parent4400478ba3d939b680810aa004f1e954b4f8ba16 (diff)
parented8b752bccf2560e305e25125721d2f0ac759e88 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: (34 commits) dm table: set flush capability based on underlying devices dm crypt: optionally support discard requests dm raid: add md raid1 support dm raid: support metadata devices dm raid: add write_mostly parameter dm raid: add region_size parameter dm raid: improve table parameters documentation dm ioctl: forbid multiple device specifiers dm ioctl: introduce __get_dev_cell dm ioctl: fill in device parameters in more ioctls dm flakey: add corrupt_bio_byte feature dm flakey: add drop_writes dm flakey: support feature args dm flakey: use dm_target_offset and support discards dm table: share target argument parsing functions dm snapshot: skip reading origin when overwriting complete chunk dm: ignore merge_bvec for snapshots when safe dm table: clean dm_get_device and move exports dm raid: tidy includes dm ioctl: prevent empty message ...
-rw-r--r--Documentation/device-mapper/dm-crypt.txt21
-rw-r--r--Documentation/device-mapper/dm-flakey.txt48
-rw-r--r--Documentation/device-mapper/dm-raid.txt138
-rw-r--r--drivers/md/Kconfig5
-rw-r--r--drivers/md/dm-crypt.c62
-rw-r--r--drivers/md/dm-flakey.c270
-rw-r--r--drivers/md/dm-io.c29
-rw-r--r--drivers/md/dm-ioctl.c89
-rw-r--r--drivers/md/dm-kcopyd.c42
-rw-r--r--drivers/md/dm-log-userspace-base.c3
-rw-r--r--drivers/md/dm-log.c32
-rw-r--r--drivers/md/dm-mpath.c147
-rw-r--r--drivers/md/dm-raid.c621
-rw-r--r--drivers/md/dm-snap-persistent.c80
-rw-r--r--drivers/md/dm-snap.c84
-rw-r--r--drivers/md/dm-table.c155
-rw-r--r--drivers/md/dm.c75
-rw-r--r--drivers/md/dm.h2
-rw-r--r--include/linux/device-mapper.h43
-rw-r--r--include/linux/dm-ioctl.h4
-rw-r--r--include/linux/dm-kcopyd.h15
21 files changed, 1561 insertions, 404 deletions
diff --git a/Documentation/device-mapper/dm-crypt.txt b/Documentation/device-mapper/dm-crypt.txt
index 6b5c42dbbe8..2c656ae43ba 100644
--- a/Documentation/device-mapper/dm-crypt.txt
+++ b/Documentation/device-mapper/dm-crypt.txt
@@ -4,7 +4,8 @@ dm-crypt
Device-Mapper's "crypt" target provides transparent encryption of block devices
using the kernel crypto API.
-Parameters: <cipher> <key> <iv_offset> <device path> <offset>
+Parameters: <cipher> <key> <iv_offset> <device path> \
+ <offset> [<#opt_params> <opt_params>]
<cipher>
Encryption cipher and an optional IV generation mode.
@@ -37,6 +38,24 @@ Parameters: <cipher> <key> <iv_offset> <device path> <offset>
<offset>
Starting sector within the device where the encrypted data begins.
+<#opt_params>
+ Number of optional parameters. If there are no optional parameters,
+ the optional paramaters section can be skipped or #opt_params can be zero.
+ Otherwise #opt_params is the number of following arguments.
+
+ Example of optional parameters section:
+ 1 allow_discards
+
+allow_discards
+ Block discard requests (a.k.a. TRIM) are passed through the crypt device.
+ The default is to ignore discard requests.
+
+ WARNING: Assess the specific security risks carefully before enabling this
+ option. For example, allowing discards on encrypted devices may lead to
+ the leak of information about the ciphertext device (filesystem type,
+ used space etc.) if the discarded blocks can be located easily on the
+ device later.
+
Example scripts
===============
LUKS (Linux Unified Key Setup) is now the preferred way to set up disk
diff --git a/Documentation/device-mapper/dm-flakey.txt b/Documentation/device-mapper/dm-flakey.txt
index c8efdfd19a6..6ff5c232722 100644
--- a/Documentation/device-mapper/dm-flakey.txt
+++ b/Documentation/device-mapper/dm-flakey.txt
@@ -1,17 +1,53 @@
dm-flakey
=========
-This target is the same as the linear target except that it returns I/O
-errors periodically. It's been found useful in simulating failing
-devices for testing purposes.
+This target is the same as the linear target except that it exhibits
+unreliable behaviour periodically. It's been found useful in simulating
+failing devices for testing purposes.
Starting from the time the table is loaded, the device is available for
-<up interval> seconds, then returns errors for <down interval> seconds,
-and then this cycle repeats.
+<up interval> seconds, then exhibits unreliable behaviour for <down
+interval> seconds, and then this cycle repeats.
-Parameters: <dev path> <offset> <up interval> <down interval>
+Also, consider using this in combination with the dm-delay target too,
+which can delay reads and writes and/or send them to different
+underlying devices.
+
+Table parameters
+----------------
+ <dev path> <offset> <up interval> <down interval> \
+ [<num_features> [<feature arguments>]]
+
+Mandatory parameters:
<dev path>: Full pathname to the underlying block-device, or a
"major:minor" device-number.
<offset>: Starting sector within the device.
<up interval>: Number of seconds device is available.
<down interval>: Number of seconds device returns errors.
+
+Optional feature parameters:
+ If no feature parameters are present, during the periods of
+ unreliability, all I/O returns errors.
+
+ drop_writes:
+ All write I/O is silently ignored.
+ Read I/O is handled correctly.
+
+ corrupt_bio_byte <Nth_byte> <direction> <value> <flags>:
+ During <down interval>, replace <Nth_byte> of the data of
+ each matching bio with <value>.
+
+ <Nth_byte>: The offset of the byte to replace.
+ Counting starts at 1, to replace the first byte.
+ <direction>: Either 'r' to corrupt reads or 'w' to corrupt writes.
+ 'w' is incompatible with drop_writes.
+ <value>: The value (from 0-255) to write.
+ <flags>: Perform the replacement only if bio->bi_rw has all the
+ selected flags set.
+
+Examples:
+ corrupt_bio_byte 32 r 1 0
+ - replaces the 32nd byte of READ bios with the value 1
+
+ corrupt_bio_byte 224 w 0 32
+ - replaces the 224th byte of REQ_META (=32) bios with the value 0
diff --git a/Documentation/device-mapper/dm-raid.txt b/Documentation/device-mapper/dm-raid.txt
index 33b6b7071ac..2a8c11331d2 100644
--- a/Documentation/device-mapper/dm-raid.txt
+++ b/Documentation/device-mapper/dm-raid.txt
@@ -1,70 +1,108 @@
-Device-mapper RAID (dm-raid) is a bridge from DM to MD. It
-provides a way to use device-mapper interfaces to access the MD RAID
-drivers.
+dm-raid
+-------
-As with all device-mapper targets, the nominal public interfaces are the
-constructor (CTR) tables and the status outputs (both STATUSTYPE_INFO
-and STATUSTYPE_TABLE). The CTR table looks like the following:
+The device-mapper RAID (dm-raid) target provides a bridge from DM to MD.
+It allows the MD RAID drivers to be accessed using a device-mapper
+interface.
-1: <s> <l> raid \
-2: <raid_type> <#raid_params> <raid_params> \
-3: <#raid_devs> <meta_dev1> <dev1> .. <meta_devN> <devN>
-
-Line 1 contains the standard first three arguments to any device-mapper
-target - the start, length, and target type fields. The target type in
-this case is "raid".
-
-Line 2 contains the arguments that define the particular raid
-type/personality/level, the required arguments for that raid type, and
-any optional arguments. Possible raid types include: raid4, raid5_la,
-raid5_ls, raid5_rs, raid6_zr, raid6_nr, and raid6_nc. (raid1 is
-planned for the future.) The list of required and optional parameters
-is the same for all the current raid types. The required parameters are
-positional, while the optional parameters are given as key/value pairs.
-The possible parameters are as follows:
- <chunk_size> Chunk size in sectors.
- [[no]sync] Force/Prevent RAID initialization
- [rebuild <idx>] Rebuild the drive indicated by the index
- [daemon_sleep <ms>] Time between bitmap daemon work to clear bits
- [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
- [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
- [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
- [stripe_cache <sectors>] Stripe cache size for higher RAIDs
-
-Line 3 contains the list of devices that compose the array in
-metadata/data device pairs. If the metadata is stored separately, a '-'
-is given for the metadata device position. If a drive has failed or is
-missing at creation time, a '-' can be given for both the metadata and
-data drives for a given position.
-
-NB. Currently all metadata devices must be specified as '-'.
-
-Examples:
-# RAID4 - 4 data drives, 1 parity
+The target is named "raid" and it accepts the following parameters:
+
+ <raid_type> <#raid_params> <raid_params> \
+ <#raid_devs> <metadata_dev0> <dev0> [.. <metadata_devN> <devN>]
+
+<raid_type>:
+ raid1 RAID1 mirroring
+ raid4 RAID4 dedicated parity disk
+ raid5_la RAID5 left asymmetric
+ - rotating parity 0 with data continuation
+ raid5_ra RAID5 right asymmetric
+ - rotating parity N with data continuation
+ raid5_ls RAID5 left symmetric
+ - rotating parity 0 with data restart
+ raid5_rs RAID5 right symmetric
+ - rotating parity N with data restart
+ raid6_zr RAID6 zero restart
+ - rotating parity zero (left-to-right) with data restart
+ raid6_nr RAID6 N restart
+ - rotating parity N (right-to-left) with data restart
+ raid6_nc RAID6 N continue
+ - rotating parity N (right-to-left) with data continuation
+
+ Refererence: Chapter 4 of
+ http://www.snia.org/sites/default/files/SNIA_DDF_Technical_Position_v2.0.pdf
+
+<#raid_params>: The number of parameters that follow.
+
+<raid_params> consists of
+ Mandatory parameters:
+ <chunk_size>: Chunk size in sectors. This parameter is often known as
+ "stripe size". It is the only mandatory parameter and
+ is placed first.
+
+ followed by optional parameters (in any order):
+ [sync|nosync] Force or prevent RAID initialization.
+
+ [rebuild <idx>] Rebuild drive number idx (first drive is 0).
+
+ [daemon_sleep <ms>]
+ Interval between runs of the bitmap daemon that
+ clear bits. A longer interval means less bitmap I/O but
+ resyncing after a failure is likely to take longer.
+
+ [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
+ [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
+ [write_mostly <idx>] Drive index is write-mostly
+ [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
+ [stripe_cache <sectors>] Stripe cache size (higher RAIDs only)
+ [region_size <sectors>]
+ The region_size multiplied by the number of regions is the
+ logical size of the array. The bitmap records the device
+ synchronisation state for each region.
+
+<#raid_devs>: The number of devices composing the array.
+ Each device consists of two entries. The first is the device
+ containing the metadata (if any); the second is the one containing the
+ data.
+
+ If a drive has failed or is missing at creation time, a '-' can be
+ given for both the metadata and data drives for a given position.
+
+
+Example tables
+--------------
+# RAID4 - 4 data drives, 1 parity (no metadata devices)
# No metadata devices specified to hold superblock/bitmap info
# Chunk size of 1MiB
# (Lines separated for easy reading)
+
0 1960893648 raid \
raid4 1 2048 \
5 - 8:17 - 8:33 - 8:49 - 8:65 - 8:81
-# RAID4 - 4 data drives, 1 parity (no metadata devices)
+# RAID4 - 4 data drives, 1 parity (with metadata devices)
# Chunk size of 1MiB, force RAID initialization,
# min recovery rate at 20 kiB/sec/disk
+
0 1960893648 raid \
- raid4 4 2048 min_recovery_rate 20 sync\
- 5 - 8:17 - 8:33 - 8:49 - 8:65 - 8:81
+ raid4 4 2048 sync min_recovery_rate 20 \
+ 5 8:17 8:18 8:33 8:34 8:49 8:50 8:65 8:66 8:81 8:82
-Performing a 'dmsetup table' should display the CTR table used to
-construct the mapping (with possible reordering of optional
-parameters).
+'dmsetup table' displays the table used to construct the mapping.
+The optional parameters are always printed in the order listed
+above with "sync" or "nosync" always output ahead of the other
+arguments, regardless of the order used when originally loading the table.
+Arguments that can be repeated are ordered by value.
-Performing a 'dmsetup status' will yield information on the state and
-health of the array. The output is as follows:
+'dmsetup status' yields information on the state and health of the
+array.
+The output is as follows:
1: <s> <l> raid \
2: <raid_type> <#devices> <1 health char for each dev> <resync_ratio>
-Line 1 is standard DM output. Line 2 is best shown by example:
+Line 1 is the standard output produced by device-mapper.
+Line 2 is produced by the raid target, and best explained by example:
0 1960893648 raid raid4 5 AAAAA 2/490221568
Here we can see the RAID type is raid4, there are 5 devices - all of
which are 'A'live, and the array is 2/490221568 complete with recovery.
+Faulty or missing devices are marked 'D'. Devices that are out-of-sync
+are marked 'a'.
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 8420129fc5e..f75a66e7d31 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -241,12 +241,13 @@ config DM_MIRROR
needed for live data migration tools such as 'pvmove'.
config DM_RAID
- tristate "RAID 4/5/6 target (EXPERIMENTAL)"
+ tristate "RAID 1/4/5/6 target (EXPERIMENTAL)"
depends on BLK_DEV_DM && EXPERIMENTAL
+ select MD_RAID1
select MD_RAID456
select BLK_DEV_MD
---help---
- A dm target that supports RAID4, RAID5 and RAID6 mappings
+ A dm target that supports RAID1, RAID4, RAID5 and RAID6 mappings
A RAID-5 set of N drives with a capacity of C MB per drive provides
the capacity of C * (N - 1) MB, and protects against a failure
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index bae6c4e23d3..49da55c1528 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -30,7 +30,6 @@
#include <linux/device-mapper.h>
#define DM_MSG_PREFIX "crypt"
-#define MESG_STR(x) x, sizeof(x)
/*
* context holding the current state of a multi-part conversion
@@ -239,7 +238,7 @@ static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
memset(iv, 0, cc->iv_size);
- *(u32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
+ *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
return 0;
}
@@ -248,7 +247,7 @@ static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
memset(iv, 0, cc->iv_size);
- *(u64 *)iv = cpu_to_le64(dmreq->iv_sector);
+ *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
return 0;
}
@@ -415,7 +414,7 @@ static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
struct crypto_cipher *essiv_tfm = this_crypt_config(cc)->iv_private;
memset(iv, 0, cc->iv_size);
- *(u64 *)iv = cpu_to_le64(dmreq->iv_sector);
+ *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
return 0;
@@ -1575,11 +1574,17 @@ bad_mem:
static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
{
struct crypt_config *cc;
- unsigned int key_size;
+ unsigned int key_size, opt_params;
unsigned long long tmpll;
int ret;
+ struct dm_arg_set as;
+ const char *opt_string;
+
+ static struct dm_arg _args[] = {
+ {0, 1, "Invalid number of feature args"},
+ };
- if (argc != 5) {
+ if (argc < 5) {
ti->error = "Not enough arguments";
return -EINVAL;
}
@@ -1648,6 +1653,30 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
}
cc->start = tmpll;
+ argv += 5;
+ argc -= 5;
+
+ /* Optional parameters */
+ if (argc) {
+ as.argc = argc;
+ as.argv = argv;
+
+ ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
+ if (ret)
+ goto bad;
+
+ opt_string = dm_shift_arg(&as);
+
+ if (opt_params == 1 && opt_string &&
+ !strcasecmp(opt_string, "allow_discards"))
+ ti->num_discard_requests = 1;
+ else if (opt_params) {
+ ret = -EINVAL;
+ ti->error = "Invalid feature arguments";
+ goto bad;
+ }
+ }
+
ret = -ENOMEM;
cc->io_queue = alloc_workqueue("kcryptd_io",
WQ_NON_REENTRANT|
@@ -1682,9 +1711,16 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
struct dm_crypt_io *io;
struct crypt_config *cc;
- if (bio->bi_rw & REQ_FLUSH) {
+ /*
+ * If bio is REQ_FLUSH or REQ_DISCARD, just bypass crypt queues.
+ * - for REQ_FLUSH device-mapper core ensures that no IO is in-flight
+ * - for REQ_DISCARD caller must use flush if IO ordering matters
+ */
+ if (unlikely(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) {
cc = ti->private;
bio->bi_bdev = cc->dev->bdev;
+ if (bio_sectors(bio))
+ bio->bi_sector = cc->start + dm_target_offset(ti, bio->bi_sector);
return DM_MAPIO_REMAPPED;
}
@@ -1727,6 +1763,10 @@ static int crypt_status(struct dm_target *ti, status_type_t type,
DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
cc->dev->name, (unsigned long long)cc->start);
+
+ if (ti->num_discard_requests)
+ DMEMIT(" 1 allow_discards");
+
break;
}
return 0;
@@ -1770,12 +1810,12 @@ static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
if (argc < 2)
goto error;
- if (!strnicmp(argv[0], MESG_STR("key"))) {
+ if (!strcasecmp(argv[0], "key")) {
if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
DMWARN("not suspended during key manipulation.");
return -EINVAL;
}
- if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) {
+ if (argc == 3 && !strcasecmp(argv[1], "set")) {
ret = crypt_set_key(cc, argv[2]);
if (ret)
return ret;
@@ -1783,7 +1823,7 @@ static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
ret = cc->iv_gen_ops->init(cc);
return ret;
}
- if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) {
+ if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
ret = cc->iv_gen_ops->wipe(cc);
if (ret)
@@ -1823,7 +1863,7 @@ static int crypt_iterate_devices(struct dm_target *ti,
static struct target_type crypt_target = {
.name = "crypt",
- .version = {1, 10, 0},
+ .version = {1, 11, 0},
.module = THIS_MODULE,
.ctr = crypt_ctr,
.dtr = crypt_dtr,
diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index ea790623c30..89f73ca22cf 100644
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -1,6 +1,6 @@
/*
* Copyright (C) 2003 Sistina Software (UK) Limited.
- * Copyright (C) 2004, 2010 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2004, 2010-2011 Red Hat, Inc. All rights reserved.
*
* This file is released under the GPL.
*/
@@ -15,6 +15,9 @@
#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.
@@ -25,60 +28,189 @@ struct flakey_c {
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
};
+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";
+
+ 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>
+ * 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 tmp;
+ unsigned long long tmpll;
+ struct dm_arg_set as;
+ const char *devname;
- if (argc != 4) {
- ti->error = "dm-flakey: Invalid argument count";
+ as.argc = argc;
+ as.argv = argv;
+
+ if (argc < 4) {
+ ti->error = "Invalid argument count";
return -EINVAL;
}
- fc = kmalloc(sizeof(*fc), GFP_KERNEL);
+ fc = kzalloc(sizeof(*fc), GFP_KERNEL);
if (!fc) {
- ti->error = "dm-flakey: Cannot allocate linear context";
+ ti->error = "Cannot allocate linear context";
return -ENOMEM;
}
fc->start_time = jiffies;
- if (sscanf(argv[1], "%llu", &tmp) != 1) {
- ti->error = "dm-flakey: Invalid device sector";
+ devname = dm_shift_arg(&as);
+
+ if (sscanf(dm_shift_arg(&as), "%llu", &tmpll) != 1) {
+ ti->error = "Invalid device sector";
goto bad;
}
- fc->start = tmp;
+ fc->start = tmpll;
- if (sscanf(argv[2], "%u", &fc->up_interval) != 1) {
- ti->error = "dm-flakey: Invalid up interval";
+ r = dm_read_arg(_args, &as, &fc->up_interval, &ti->error);
+ if (r)
goto bad;
- }
- if (sscanf(argv[3], "%u", &fc->down_interval) != 1) {
- ti->error = "dm-flakey: Invalid down interval";
+ r = dm_read_arg(_args, &as, &fc->down_interval, &ti->error);
+ if (r)
goto bad;
- }
if (!(fc->up_interval + fc->down_interval)) {
- ti->error = "dm-flakey: Total (up + down) interval is zero";
+ ti->error = "Total (up + down) interval is zero";
goto bad;
}
if (fc->up_interval + fc->down_interval < fc->up_interval) {
- ti->error = "dm-flakey: Interval overflow";
+ ti->error = "Interval overflow";
goto bad;
}
- if (dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &fc->dev)) {
- ti->error = "dm-flakey: Device lookup failed";
+ 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_requests = 1;
+ ti->num_discard_requests = 1;
ti->private = fc;
return 0;
@@ -99,7 +231,7 @@ static sector_t flakey_map_sector(struct dm_target *ti, sector_t bi_sector)
{
struct flakey_c *fc = ti->private;
- return fc->start + (bi_sector - ti->begin);
+ return fc->start + dm_target_offset(ti, bi_sector);
}
static void flakey_map_bio(struct dm_target *ti, struct bio *bio)
@@ -111,6 +243,25 @@ static void flakey_map_bio(struct dm_target *ti, struct bio *bio)
bio->bi_sector = flakey_map_sector(ti, bio->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_sector, bio_bytes);
+ }
+}
+
static int flakey_map(struct dm_target *ti, struct bio *bio,
union map_info *map_context)
{
@@ -119,18 +270,71 @@ static int flakey_map(struct dm_target *ti, struct bio *bio,
/* Are we alive ? */
elapsed = (jiffies - fc->start_time) / HZ;
- if (elapsed % (fc->up_interval + fc->down_interval) >= fc->up_interval)
+ if (elapsed % (fc->up_interval + fc->down_interval) >= fc->up_interval) {
+ /*
+ * Flag this bio as submitted while down.
+ */
+ map_context->ll = 1;
+
+ /*
+ * 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, union map_info *map_context)
+{
+ struct flakey_c *fc = ti->private;
+ unsigned bio_submitted_while_down = map_context->ll;
+
+ /*
+ * Corrupt successful READs while in down state.
+ * If flags were specified, only corrupt those that match.
+ */
+ if (!error && bio_submitted_while_down &&
+ (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 int flakey_status(struct dm_target *ti, status_type_t type,
char *result, unsigned int maxlen)
{
+ unsigned sz = 0;
struct flakey_c *fc = ti->private;
+ unsigned drop_writes;
switch (type) {
case STATUSTYPE_INFO:
@@ -138,9 +342,22 @@ static int flakey_status(struct dm_target *ti, status_type_t type,
break;
case STATUSTYPE_TABLE:
- snprintf(result, maxlen, "%s %llu %u %u", fc->dev->name,
- (unsigned long long)fc->start, fc->up_interval,
- fc->down_interval);
+ 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;
}
return 0;
@@ -177,11 +394,12 @@ static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_
static struct target_type flakey_target = {
.name = "flakey",
- .version = {1, 1, 0},
+ .version = {1, 2, 0},
.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,
diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index 2067288f61f..ad2eba40e31 100644
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -38,6 +38,8 @@ struct io {
struct dm_io_client *client;
io_notify_fn callback;
void *context;
+ void *vma_invalidate_address;
+ unsigned long vma_invalidate_size;
} __attribute__((aligned(DM_IO_MAX_REGIONS)));
static struct kmem_cache *_dm_io_cache;
@@ -116,6 +118,10 @@ static void dec_count(struct io *io, unsigned int region, int error)
set_bit(region, &io->error_bits);
if (atomic_dec_and_test(&io->count)) {
+ if (io->vma_invalidate_size)
+ invalidate_kernel_vmap_range(io->vma_invalidate_address,
+ io->vma_invalidate_size);
+
if (io->sleeper)
wake_up_process(io->sleeper);
@@ -159,6 +165,9 @@ struct dpages {
unsigned context_u;
void *context_ptr;
+
+ void *vma_invalidate_address;
+ unsigned long vma_invalidate_size;
};
/*
@@ -377,6 +386,9 @@ static int sync_io(struct dm_io_client *client, unsigned int num_regions,
io->sleeper = current;
io->client = client;
+ io->vma_invalidate_address = dp->vma_invalidate_address;
+ io->vma_invalidate_size = dp->vma_invalidate_size;
+
dispatch_io(rw, num_regions, where, dp, io, 1);
while (1) {
@@ -415,13 +427,21 @@ static int async_io(struct dm_io_client *client, unsigned int num_regions,
io->callback = fn;
io->context = context;
+ io->vma_invalidate_address = dp->vma_invalidate_address;
+ io->vma_invalidate_size = dp->vma_invalidate_size;
+
dispatch_io(rw, num_regions, where, dp, io, 0);
return 0;
}
-static int dp_init(struct dm_io_request *io_req, struct dpages *dp)
+static int dp_init(struct dm_io_request *io_req, struct dpages *dp,
+ unsigned long size)
{
/* Set up dpages based on memory type */
+
+ dp->vma_invalidate_address = NULL;
+ dp->vma_invalidate_size = 0;
+
switch (io_req->mem.type) {
case DM_IO_PAGE_LIST:
list_dp_init(dp, io_req->mem.ptr.pl, io_req->mem.offset);
@@ -432,6 +452,11 @@ static int dp_init(struct dm_io_request *io_req, struct dpages *dp)
break;
case DM_IO_VMA:
+ flush_kernel_vmap_range(io_req->mem.ptr.vma, size);
+ if ((io_req->bi_rw & RW_MASK) == READ) {
+ dp->vma_invalidate_address = io_req->mem.ptr.vma;
+ dp->vma_invalidate_size = size;
+ }
vm_dp_init(dp, io_req->mem.ptr.vma);
break;
@@ -460,7 +485,7 @@ int dm_io(struct dm_io_request *io_req, unsigned num_regions,
int r;
struct dpages dp;
- r = dp_init(io_req, &dp);
+ r = dp_init(io_req, &dp, (unsigned long)where->count << SECTOR_SHIFT);
if (r)
return r;
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 4cacdad2270..2e9a3ca37bd 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -128,6 +128,24 @@ static struct hash_cell *__get_uuid_cell(const char *str)
return NULL;
}
+static struct hash_cell *__get_dev_cell(uint64_t dev)
+{
+ struct mapped_device *md;
+ struct hash_cell *hc;
+
+ md = dm_get_md(huge_decode_dev(dev));
+ if (!md)
+ return NULL;
+
+ hc = dm_get_mdptr(md);
+ if (!hc) {
+ dm_put(md);
+ return NULL;
+ }
+
+ return hc;
+}
+
/*-----------------------------------------------------------------
* Inserting, removing and renaming a device.
*---------------------------------------------------------------*/
@@ -718,25 +736,45 @@ static int dev_create(struct dm_ioctl *param, size_t param_size)
*/
static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
{
- struct mapped_device *md;
- void *mdptr = NULL;
+ struct hash_cell *hc = NULL;
- if (*param->uuid)
- return __get_uuid_cell(param->uuid);
+ if (*param->uuid) {
+ if (*param->name || param->dev)
+ return NULL;
- if (*param->name)
- return __get_name_cell(param->name);
+ hc = __get_uuid_cell(param->uuid);
+ if (!hc)
+ return NULL;
+ } else if (*param->name) {
+ if (param->dev)
+ return NULL;
- md = dm_get_md(huge_decode_dev(param->dev));
- if (!md)
- goto out;
+ hc = __get_name_cell(param->name);
+ if (!hc)
+ return NULL;
+ } else if (param->dev) {
+ hc = __get_dev_cell(param->dev);
+ if (!hc)
+ return NULL;
+ } else
+ return NULL;
- mdptr = dm_get_mdptr(md);
- if (!mdptr)
- dm_put(md);
+ /*
+ * Sneakily write in both the name and the uuid
+ * while we have the cell.
+ */
+ strlcpy(param->name, hc->name, sizeof(param->name));
+ if (hc->uuid)
+ strlcpy(param->uuid, hc->uuid, sizeof(param->uuid));
+ else
+ param->uuid[0] = '\0';
-out:
- return mdptr;
+ if (hc->new_map)
+ param->flags |= DM_INACTIVE_PRESENT_FLAG;
+ else
+ param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
+
+ return hc;
}
static struct mapped_device *find_device(struct dm_ioctl *param)
@@ -746,24 +784,8 @@ static struct mapped_device *find_device(struct dm_ioctl *param)
down_read(&_hash_lock);
hc = __find_device_hash_cell(param);
- if (hc) {
+ if (hc)
md = hc->md;
-
- /*
- * Sneakily write in both the name and the uuid
- * while we have the cell.
- */
- strlcpy(param->name, hc->name, sizeof(param->name));
- if (hc->uuid)
- strlcpy(param->uuid, hc->uuid, sizeof(param->uuid));
- else
- param->uuid[0] = '\0';
-
- if (hc->new_map)
- param->flags |= DM_INACTIVE_PRESENT_FLAG;
- else
- param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
- }
up_read(&_hash_lock);
return md;
@@ -1402,6 +1424,11 @@ static int target_message(struct dm_ioctl *param, size_t param_size)
goto out;
}
+ if (!argc) {
+ DMWARN("Empty message received.");
+ goto out;
+ }
+
table = dm_get_live_table(md);
if (!table)
goto out_argv;
diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c
index 320401dec10..f8214702963 100644
--- a/drivers/md/dm-kcopyd.c
+++ b/drivers/md/dm-kcopyd.c
@@ -224,8 +224,6 @@ struct kcopyd_job {
unsigned int num_dests;
struct dm_io_region dests[DM_KCOPYD_MAX_REGIONS];
- sector_t offset;
- unsigned int nr_pages;
struct page_list *pages;
/*
@@ -380,7 +378,7 @@ static int run_io_job(struct kcopyd_job *job)
.bi_rw = job->rw,
.mem.type = DM_IO_PAGE_LIST,
.mem.ptr.pl = job->pages,
- .mem.offset = job->offset,
+ .mem.offset = 0,
.notify.fn = complete_io,
.notify.context = job,
.client = job->kc->io_client,
@@ -397,10 +395,9 @@ static int run_io_job(struct kcopyd_job *job)
static int run_pages_job(struct kcopyd_job *job)
{
int r;
+ unsigned nr_pages = dm_div_up(job->dests[0].count, PAGE_SIZE >> 9);
- job->nr_pages = dm_div_up(job->dests[0].count + job->offset,
- PAGE_SIZE >> 9);
- r = kcopyd_get_pages(job->kc, job->nr_pages, &job->pages);
+ r = kcopyd_get_pages(job->kc, nr_pages, &job->pages);
if (!r) {
/* this job is ready for io */
push(&job->kc->io_jobs, job);
@@ -602,8 +599,6 @@ int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
job->num_dests = num_dests;
memcpy(&job->dests, dests, sizeof(*dests) * num_dests);
- job->offset = 0;
- job->nr_pages = 0;
job->pages = NULL;
job->fn = fn;
@@ -622,6 +617,37 @@ int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
}
EXPORT_SYMBOL(dm_kcopyd_copy);
+void *dm_kcopyd_prepare_callback(struct dm_kcopyd_client *kc,
+ dm_kcopyd_notify_fn fn, void *context)
+{
+ struct kcopyd_job *job;
+
+ job = mempool_alloc(kc->job_pool, GFP_NOIO);
+
+ memset(job, 0, sizeof(struct kcopyd_job));
+ job->kc = kc;
+ job->fn = fn;
+ job->context = context;
+
+ atomic_inc(&kc->nr_jobs);
+
+ return job;
+}
+EXPORT_SYMBOL(dm_kcopyd_prepare_callback);
+
+void dm_kcopyd_do_callback(void *j, int read_err, unsigned long write_err)
+{
+ struct kcopyd_job *job = j;
+ struct dm_kcopyd_client *kc = job->kc;
+
+ job->read_err = read_err;
+ job->write_err = write_err;
+
+ push(&kc->complete_jobs, job);
+ wake(kc);
+}
+EXPORT_SYMBOL(dm_kcopyd_do_callback);
+
/*
* Cancels a kcopyd job, eg. someone might be deactivating a
* mirror.
diff --git a/drivers/md/dm-log-userspace-base.c b/drivers/md/dm-log-userspace-base.c
index aa2e0c374ab..1021c898601 100644
--- a/drivers/md/dm-log-userspace-base.c
+++ b/drivers/md/dm-log-userspace-base.c
@@ -394,8 +394,7 @@ static int flush_by_group(struct log_c *lc, struct list_head *flush_list)
group[count] = fe->region;
count++;
- list_del(&fe->list);
- list_add(&fe->list, &tmp_list);
+ list_move(&fe->list, &tmp_list);
type = fe->type;
if (count >= MAX_FLUSH_GROUP_COUNT)
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c
index 948e3f4925b..3b52bb72bd1 100644
--- a/drivers/md/dm-log.c
+++ b/drivers/md/dm-log.c
@@ -197,15 +197,21 @@ EXPORT_SYMBOL(dm_dirty_log_destroy);
#define MIRROR_DISK_VERSION 2
#define LOG_OFFSET 2
-struct log_header {
- uint32_t magic;
+struct log_header_disk {
+ __le32 magic;
/*
* Simple, incrementing version. no backward
* compatibility.
*/
+ __le32 version;
+ __le64 nr_regions;
+} __packed;
+
+struct log_header_core {
+ uint32_t magic;
uint32_t version;
- sector_t nr_regions;
+ uint64_t nr_regions;
};
struct log_c {
@@ -239,10 +245,10 @@ struct log_c {
int log_dev_failed;
int log_dev_flush_failed;
struct dm_dev *log_dev;
- struct log_header header;
+ struct log_header_core header;
struct dm_io_region header_location;
- struct log_header *disk_header;
+ struct log_header_disk *disk_header;
};
/*
@@ -251,34 +257,34 @@ struct log_c {
*/
static inline int log_test_bit(uint32_t *bs, unsigned bit)
{
- return test_bit_le(bit, (unsigned long *) bs) ? 1 : 0;
+ return test_bit_le(bit, bs) ? 1 : 0;
}
static inline void log_set_bit(struct log_c *l,
uint32_t *bs, unsigned bit)
{
- __test_and_set_bit_le(bit, (unsigned long *) bs);
+ __set_bit_le(bit, bs);
l->touched_cleaned = 1;
}
static inline void log_clear_bit(struct log_c *l,
uint32_t *bs, unsigned bit)
{
- __test_and_clear_bit_le(bit, (unsigned long *) bs);
+ __clear_bit_le(bit, bs);
l->touched_dirtied = 1;
}
/*----------------------------------------------------------------
* Header IO
*--------------------------------------------------------------*/
-static void header_to_disk(struct log_header *core, struct log_header *disk)
+static void header_to_disk(struct log_header_core *core, struct log_header_disk *disk)
{
disk->magic = cpu_to_le32(core->magic);
disk->version = cpu_to_le32(core->version);
disk->nr_regions = cpu_to_le64(core->nr_regions);
}
-static void header_from_disk(struct log_header *core, struct log_header *disk)
+static void header_from_disk(struct log_header_core *core, struct log_header_disk *disk)
{
core->magic = le32_to_cpu(disk->magic);
core->version = le32_to_cpu(disk->version);
@@ -486,7 +492,7 @@ static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti,
memset(lc->sync_bits, (sync == NOSYNC) ? -1 : 0, bitset_size);
lc->sync_count = (sync == NOSYNC) ? region_count : 0;
- lc->recovering_bits = vmalloc(bitset_size);
+ lc->recovering_bits = vzalloc(bitset_size);
if (!lc->recovering_bits) {
DMWARN("couldn't allocate sync bitset");
vfree(lc->sync_bits);
@@ -498,7 +504,6 @@ static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti,
kfree(lc);
return -ENOMEM;
}
- memset(lc->recovering_bits, 0, bitset_size);
lc->sync_search = 0;
log->context = lc;
@@ -739,8 +744,7 @@ static int core_get_resync_work(struct dm_dirty_log *log, region_t *region)
return 0;
do {
- *region = find_next_zero_bit_le(
- (unsigned long *) lc->sync_bits,
+ *region = find_next_zero_bit_le(lc->sync_bits,
lc->region_count,
lc->sync_search);
lc->sync_search = *region + 1;
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index c3547016f0f..5e0090ef418 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -22,7 +22,6 @@
#include <linux/atomic.h>
#define DM_MSG_PREFIX "multipath"
-#define MESG_STR(x) x, sizeof(x)
#define DM_PG_INIT_DELAY_MSECS 2000
#define DM_PG_INIT_DELAY_DEFAULT ((unsigned) -1)
@@ -505,80 +504,29 @@ static void trigger_event(struct work_struct *work)
* <#paths> <#per-path selector args>
* [<path> [<arg>]* ]+ ]+
*---------------------------------------------------------------*/
-struct param {
- unsigned min;
- unsigned max;
- char *error;
-};
-
-static int read_param(struct param *param, char *str, unsigned *v, char **error)
-{
- if (!str ||
- (sscanf(str, "%u", v) != 1) ||
- (*v < param->min) ||
- (*v > param->max)) {
- *error = param->error;
- return -EINVAL;
- }
-
- return 0;
-}
-
-struct arg_set {
- unsigned argc;
- char **argv;
-};
-
-static char *shift(struct arg_set *as)
-{
- char *r;
-
- if (as->argc) {
- as->argc--;
- r = *as->argv;
- as->argv++;
- return r;
- }
-
- return NULL;
-}
-
-static void consume(struct arg_set *as, unsigned n)
-{
- BUG_ON (as->argc < n);
- as->argc -= n;
- as->argv += n;
-}
-
-static int parse_path_selector(struct arg_set *as, struct priority_group *pg,
+static int parse_path_selector(struct dm_arg_set *as, struct priority_group *pg,
struct dm_target *ti)
{
int r;
struct path_selector_type *pst;
unsigned ps_argc;
- static struct param _params[] = {
+ static struct dm_arg _args[] = {
{0, 1024, "invalid number of path selector args"},
};
- pst = dm_get_path_selector(shift(as));
+ pst = dm_get_path_selector(dm_shift_arg(as));
if (!pst) {
ti->error = "unknown path selector type";
return -EINVAL;
}
- r = read_param(_params, shift(as), &ps_argc, &ti->error);
+ r = dm_read_arg_group(_args, as, &ps_argc, &ti->error);
if (r) {
dm_put_path_selector(pst);
return -EINVAL;
}
- if (ps_argc > as->argc) {
- dm_put_path_selector(pst);
- ti->error = "not enough arguments for path selector";
- return -EINVAL;
- }
-
r = pst->create(&pg->ps, ps_argc, as->argv);
if (r) {
dm_put_path_selector(pst);
@@ -587,12 +535,12 @@ static int parse_path_selector(struct arg_set *as, struct priority_group *pg,
}
pg->ps.type = pst;
- consume(as, ps_argc);
+ dm_consume_args(as, ps_argc);
return 0;
}
-static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps,
+static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps,
struct dm_target *ti)
{
int r;
@@ -609,7 +557,7 @@ static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps,
if (!p)
return ERR_PTR(-ENOMEM);
- r = dm_get_device(ti, shift(as), dm_table_get_mode(ti->table),
+ r = dm_get_device(ti, dm_shift_arg(as), dm_table_get_mode(ti->table),
&p->path.dev);
if (r) {
ti->error = "error getting device";
@@ -660,16 +608,16 @@ static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps,
return ERR_PTR(r);
}
-static struct priority_group *parse_priority_group(struct arg_set *as,
+static struct priority_group *parse_priority_group(struct dm_arg_set *as,
struct multipath *m)
{
- static struct param _params[] = {
+ static struct dm_arg _args[] = {
{1, 1024, "invalid number of paths"},
{0, 1024, "invalid number of selector args"}
};
int r;
- unsigned i, nr_selector_args, nr_params;
+ unsigned i, nr_selector_args, nr_args;
struct priority_group *pg;
struct dm_target *ti = m->ti;
@@ -693,26 +641,26 @@ static struct priority_group *parse_priority_group(struct arg_set *as,
/*
* read the paths
*/
- r = read_param(_params, shift(as), &pg->nr_pgpaths, &ti->error);
+ r = dm_read_arg(_args, as, &pg->nr_pgpaths, &ti->error);
if (r)
goto bad;
- r = read_param(_params + 1, shift(as), &nr_selector_args, &ti->error);
+ r = dm_read_arg(_args + 1, as, &nr_selector_args, &ti->error);
if (r)
goto bad;
- nr_params = 1 + nr_selector_args;
+ nr_args = 1 + nr_selector_args;
for (i = 0; i < pg->nr_pgpaths; i++) {
struct pgpath *pgpath;
- struct arg_set path_args;
+ struct dm_arg_set path_args;
- if (as->argc < nr_params) {
+ if (as->argc < nr_args) {
ti->error = "not enough path parameters";
r = -EINVAL;
goto bad;
}
- path_args.argc = nr_params;
+ path_args.argc = nr_args;
path_args.argv = as->argv;
pgpath = parse_path(&path_args, &pg->ps, ti);
@@ -723,7 +671,7 @@ static struct priority_group *parse_priority_group(struct arg_set *as,
pgpath->pg = pg;
list_add_tail(&pgpath->list, &pg->pgpaths);
- consume(as, nr_params);
+ dm_consume_args(as, nr_args);
}
return pg;
@@ -733,28 +681,23 @@ static struct priority_group *parse_priority_group(struct arg_set *as,
return ERR_PTR(r);
}
-static int parse_hw_handler(struct arg_set *as, struct multipath *m)
+static int parse_hw_handler(struct dm_arg_set *as, struct multipath *m)
{
unsigned hw_argc;
int ret;
struct dm_target *ti = m->ti;
- static struct param _params[] = {
+ static struct dm_arg _args[] = {
{0, 1024, "invalid number of hardware handler args"},
};
- if (read_param(_params, shift(as), &hw_argc, &ti->error))
+ if (dm_read_arg_group(_args, as, &hw_argc, &ti->error))
return -EINVAL;
if (!hw_argc)
return 0;
- if (hw_argc > as->argc) {
- ti->error = "not enough arguments for hardware handler";
- return -EINVAL;
- }
-
- m->hw_handler_name = kstrdup(shift(as), GFP_KERNEL);
+ m->hw_handler_name = kstrdup(dm_shift_arg(as), GFP_KERNEL);
request_module("scsi_dh_%s", m->hw_handler_name);
if (scsi_dh_handler_exist(m->hw_handler_name) == 0) {
ti->error = "unknown hardware handler type";
@@ -778,7 +721,7 @@ static int parse_hw_handler(struct arg_set *as, struct multipath *m)
for (i = 0, p+=j+1; i <= hw_argc - 2; i++, p+=j+1)
j = sprintf(p, "%s", as->argv[i]);
}
- consume(as, hw_argc - 1);
+ dm_consume_args(as, hw_argc - 1);
return 0;
fail:
@@ -787,20 +730,20 @@ fail:
return ret;
}
-static int parse_features(struct arg_set *as, struct multipath *m)
+static int parse_features(struct dm_arg_set *as, struct multipath *m)
{
int r;
unsigned argc;
struct dm_target *ti = m->ti;
- const char *param_name;
+ const char *arg_name;
- static struct param _params[] = {
+ static struct dm_arg _args[] = {
{0, 5, "invalid number of feature args"},
{1, 50, "pg_init_retries must be between 1 and 50"},
{0, 60000, "pg_init_delay_msecs must be between 0 and 60000"},
};
- r = read_param(_params, shift(as), &argc, &ti->error);
+ r = dm_read_arg_group(_args, as, &argc, &ti->error);
if (r)
return -EINVAL;
@@ -808,26 +751,24 @@ static int parse_features(struct arg_set *as, struct multipath *m)
return 0;
do {
- param_name = shift(as);
+ arg_name = dm_shift_arg(as);
argc--;
- if (!strnicmp(param_name, MESG_STR("queue_if_no_path"))) {
+ if (!strcasecmp(arg_name, "queue_if_no_path")) {
r = queue_if_no_path(m, 1, 0);
continue;
}
- if (!strnicmp(param_name, MESG_STR("pg_init_retries")) &&
+ if (!strcasecmp(arg_name, "pg_init_retries") &&
(argc >= 1)) {
- r = read_param(_params + 1, shift(as),
- &m->pg_init_retries, &ti->error);
+ r = dm_read_arg(_args + 1, as, &m->pg_init_retries, &ti->error);
argc--;
continue;
}
- if (!strnicmp(param_name, MESG_STR("pg_init_delay_msecs")) &&
+ if (!strcasecmp(arg_name, "pg_init_delay_msecs") &&
(argc >= 1)) {
- r = read_param(_params + 2, shift(as),
- &m->pg_init_delay_msecs, &ti->error);
+ r = dm_read_arg(_args + 2, as, &m->pg_init_delay_msecs, &ti->error);
argc--;
continue;
}
@@ -842,15 +783,15 @@ static int parse_features(struct arg_set *as, struct multipath *m)
static int multipath_ctr(struct dm_target *ti, unsigned int argc,
char **argv)
{
- /* target parameters */
- static struct param _params[] = {
+ /* target arguments */
+ static struct dm_arg _args[] = {
{0, 1024, "invalid number of priority groups"},
{0, 1024, "invalid initial priority group number"},
};
int r;
struct multipath *m;
- struct arg_set as;
+ struct dm_arg_set as;
unsigned pg_count = 0;
unsigned next_pg_num;
@@ -871,11 +812,11 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
if (r)
goto bad;
- r = read_param(_params, shift(&as), &m->nr_priority_groups, &ti->error);
+ r = dm_read_arg(_args, &as, &m->nr_priority_groups, &ti->error);
if (r)
goto bad;
- r = read_param(_params + 1, shift(&as), &next_pg_num, &ti->error);
+ r = dm_read_arg(_args + 1, &as, &next_pg_num, &ti->error);
if (r)
goto bad;
@@ -1505,10 +1446,10 @@ static int multipath_message(struct dm_target *ti, unsigned argc, char **argv)
}
if (argc == 1) {
- if (!strnicmp(argv[0], MESG_STR("queue_if_no_path"))) {
+ if (!strcasecmp(argv[0], "queue_if_no_path")) {
r = queue_if_no_path(m, 1, 0);
goto out;
- } else if (!strnicmp(argv[0], MESG_STR("fail_if_no_path"))) {
+ } else if (!strcasecmp(argv[0], "fail_if_no_path")) {
r = queue_if_no_path(m, 0, 0);
goto out;
}
@@ -1519,18 +1460,18 @@ static int multipath_message(struct dm_target *ti, unsigned argc, char **argv)
goto out;
}
- if (!strnicmp(argv[0], MESG_STR("disable_group"))) {
+ if (!strcasecmp(argv[0], "disable_group")) {
r = bypass_pg_num(m, argv[1], 1);
goto out;
- } else if (!strnicmp(argv[0], MESG_STR("enable_group"))) {
+ } else if (!strcasecmp(argv[0], "enable_group")) {
r = bypass_pg_num(m, argv[1], 0);
goto out;
- } else if (!strnicmp(argv[0], MESG_STR("switch_group"))) {
+ } else if (!strcasecmp(argv[0], "switch_group")) {
r = switch_pg_num(m, argv[1]);
goto out;
- } else if (!strnicmp(argv[0], MESG_STR("reinstate_path")))
+ } else if (!strcasecmp(argv[0], "reinstate_path"))
action = reinstate_path;
- else if (!strnicmp(argv[0], MESG_STR("fail_path")))
+ else if (!strcasecmp(argv[0], "fail_path"))
action = fail_path;
else {
DMWARN("Unrecognised multipath message received.");
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index e5d8904fc8f..a002dd85db1 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -8,19 +8,19 @@
#include <linux/slab.h>
#include "md.h"
+#include "raid1.h"
#include "raid5.h"
-#include "dm.h"
#include "bitmap.h"
+#include <linux/device-mapper.h>
+
#define DM_MSG_PREFIX "raid"
/*
- * If the MD doesn't support MD_SYNC_STATE_FORCED yet, then
- * make it so the flag doesn't set anything.
+ * The following flags are used by dm-raid.c to set up the array state.
+ * They must be cleared before md_run is called.
*/
-#ifndef MD_SYNC_STATE_FORCED
-#define MD_SYNC_STATE_FORCED 0
-#endif
+#define FirstUse 10 /* rdev flag */
struct raid_dev {
/*
@@ -43,14 +43,15 @@ struct raid_dev {
/*
* Flags for rs->print_flags field.
*/
-#define DMPF_DAEMON_SLEEP 0x1
-#define DMPF_MAX_WRITE_BEHIND 0x2
-#define DMPF_SYNC 0x4
-#define DMPF_NOSYNC 0x8
-#define DMPF_STRIPE_CACHE 0x10
-#define DMPF_MIN_RECOVERY_RATE 0x20
-#define DMPF_MAX_RECOVERY_RATE 0x40
-
+#define DMPF_SYNC 0x1
+#define DMPF_NOSYNC 0x2
+#define DMPF_REBUILD 0x4
+#define DMPF_DAEMON_SLEEP 0x8
+#define DMPF_MIN_RECOVERY_RATE 0x10
+#define DMPF_MAX_RECOVERY_RATE 0x20
+#define DMPF_MAX_WRITE_BEHIND 0x40
+#define DMPF_STRIPE_CACHE 0x80
+#define DMPF_REGION_SIZE 0X100
struct raid_set {
struct dm_target *ti;
@@ -72,6 +73,7 @@ static struct raid_type {
const unsigned level; /* RAID level. */
const unsigned algorithm; /* RAID algorithm. */
} raid_types[] = {
+ {"raid1", "RAID1 (mirroring)", 0, 2, 1, 0 /* NONE */},
{"raid4", "RAID4 (dedicated parity disk)", 1, 2, 5, ALGORITHM_PARITY_0},
{"raid5_la", "RAID5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC},
{"raid5_ra", "RAID5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC},
@@ -105,7 +107,8 @@ static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *ra
}
sectors_per_dev = ti->len;
- if (sector_div(sectors_per_dev, (raid_devs - raid_type->parity_devs))) {
+ if ((raid_type->level > 1) &&
+ sector_div(sectors_per_dev, (raid_devs - raid_type->parity_devs))) {
ti->error = "Target length not divisible by number of data devices";
return ERR_PTR(-EINVAL);
}
@@ -147,9 +150,16 @@ static void context_free(struct raid_set *rs)
{
int i;
- for (i = 0; i < rs->md.raid_disks; i++)
+ for (i = 0; i < rs->md.raid_disks; i++) {
+ if (rs->dev[i].meta_dev)
+ dm_put_device(rs->ti, rs->dev[i].meta_dev);
+ if (rs->dev[i].rdev.sb_page)
+ put_page(rs->dev[i].rdev.sb_page);
+ rs->dev[i].rdev.sb_page = NULL;
+ rs->dev[i].rdev.sb_loaded = 0;
if (rs->dev[i].data_dev)
dm_put_device(rs->ti, rs->dev[i].data_dev);
+ }
kfree(rs);
}
@@ -159,7 +169,16 @@ static void context_free(struct raid_set *rs)
* <meta_dev>: meta device name or '-' if missing
* <data_dev>: data device name or '-' if missing
*
- * This code parses those words.
+ * The following are permitted:
+ * - -
+ * - <data_dev>
+ * <meta_dev> <data_dev>
+ *
+ * The following is not allowed:
+ * <meta_dev> -
+ *
+ * This code parses those words. If there is a failure,
+ * the caller must use context_free to unwind the operations.
*/
static int dev_parms(struct raid_set *rs, char **argv)
{
@@ -182,8 +201,16 @@ static int dev_parms(struct raid_set *rs, char **argv)
rs->dev[i].rdev.mddev = &rs->md;
if (strcmp(argv[0], "-")) {
- rs->ti->error = "Metadata devices not supported";
- return -EINVAL;
+ ret = dm_get_device(rs->ti, argv[0],
+ dm_table_get_mode(rs->ti->table),
+ &rs->dev[i].meta_dev);
+ rs->ti->error = "RAID metadata device lookup failure";
+ if (ret)
+ return ret;
+
+ rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
+ if (!rs->dev[i].rdev.sb_page)
+ return -ENOMEM;
}
if (!strcmp(argv[1], "-")) {
@@ -193,6 +220,10 @@ static int dev_parms(struct raid_set *rs, char **argv)
return -EINVAL;
}
+ rs->ti->error = "No data device supplied with metadata device";
+ if (rs->dev[i].meta_dev)
+ return -EINVAL;
+
continue;
}
@@ -204,6 +235,10 @@ static int dev_parms(struct raid_set *rs, char **argv)
return ret;
}
+ if (rs->dev[i].meta_dev) {
+ metadata_available = 1;
+ rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
+ }
rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
list_add(&rs->dev[i].rdev.same_set, &rs->md.disks);
if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
@@ -235,33 +270,109 @@ static int dev_parms(struct raid_set *rs, char **argv)
}
/*
+ * validate_region_size
+ * @rs
+ * @region_size: region size in sectors. If 0, pick a size (4MiB default).
+ *
+ * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
+ * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
+ *
+ * Returns: 0 on success, -EINVAL on failure.
+ */
+static int validate_region_size(struct raid_set *rs, unsigned long region_size)
+{
+ unsigned long min_region_size = rs->ti->len / (1 << 21);
+
+ if (!region_size) {
+ /*
+ * Choose a reasonable default. All figures in sectors.
+ */
+ if (min_region_size > (1 << 13)) {
+ DMINFO("Choosing default region size of %lu sectors",
+ region_size);
+ region_size = min_region_size;
+ } else {
+ DMINFO("Choosing default region size of 4MiB");
+ region_size = 1 << 13; /* sectors */
+ }
+ } else {
+ /*
+ * Validate user-supplied value.
+ */
+ if (region_size > rs->ti->len) {
+ rs->ti->error = "Supplied region size is too large";
+ return -EINVAL;
+ }
+
+ if (region_size < min_region_size) {
+ DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
+ region_size, min_region_size);
+ rs->ti->error = "Supplied region size is too small";
+ return -EINVAL;
+ }
+
+ if (!is_power_of_2(region_size)) {
+ rs->ti->error = "Region size is not a power of 2";
+ return -EINVAL;
+ }
+
+ if (region_size < rs->md.chunk_sectors) {
+ rs->ti->error = "Region size is smaller than the chunk size";
+ return -EINVAL;
+ }
+ }
+
+ /*
+ * Convert sectors to bytes.
+ */
+ rs->md.bitmap_info.chunksize = (region_size << 9);
+
+ return 0;
+}
+
+/*
* Possible arguments are...
- * RAID456:
* <chunk_size> [optional_args]
*
- * Optional args:
- * [[no]sync] Force or prevent recovery of the entire array
+ * Argument definitions
+ * <chunk_size> The number of sectors per disk that
+ * will form the "stripe"
+ * [[no]sync] Force or prevent recovery of the
+ * entire array
* [rebuild <idx>] Rebuild the drive indicated by the index
- * [daemon_sleep <ms>] Time between bitmap daemon work to clear bits
+ * [daemon_sleep <ms>] Time between bitmap daemon work to
+ * clear bits
* [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
* [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
+ * [write_mostly <idx>] Indicate a write mostly drive via index
* [max_write_behind <sectors>] See '-write-behind=' (man mdadm)
* [stripe_cache <sectors>] Stripe cache size for higher RAIDs
+ * [region_size <sectors>] Defines granularity of bitmap
*/
static int parse_raid_params(struct raid_set *rs, char **argv,
unsigned num_raid_params)
{
unsigned i, rebuild_cnt = 0;
- unsigned long value;
+ unsigned long value, region_size = 0;
char *key;
/*
* First, parse the in-order required arguments
+ * "chunk_size" is the only argument of this type.
*/
- if ((strict_strtoul(argv[0], 10, &value) < 0) ||
- !is_power_of_2(value) || (value < 8)) {
+ if ((strict_strtoul(argv[0], 10, &value) < 0)) {
rs->ti->error = "Bad chunk size";
return -EINVAL;
+ } else if (rs->raid_type->level == 1) {
+ if (value)
+ DMERR("Ignoring chunk size parameter for RAID 1");
+ value = 0;
+ } else if (!is_power_of_2(value)) {
+ rs->ti->error = "Chunk size must be a power of 2";
+ return -EINVAL;
+ } else if (value < 8) {
+ rs->ti->error = "Chunk size value is too small";
+ return -EINVAL;
}
rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
@@ -269,22 +380,39 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
num_raid_params--;
/*
- * Second, parse the unordered optional arguments
+ * We set each individual device as In_sync with a completed
+ * 'recovery_offset'. If there has been a device failure or
+ * replacement then one of the following cases applies:
+ *
+ * 1) User specifies 'rebuild'.
+ * - Device is reset when param is read.
+ * 2) A new device is supplied.
+ * - No matching superblock found, resets device.
+ * 3) Device failure was transient and returns on reload.
+ * - Failure noticed, resets device for bitmap replay.
+ * 4) Device hadn't completed recovery after previous failure.
+ * - Superblock is read and overrides recovery_offset.
+ *
+ * What is found in the superblocks of the devices is always
+ * authoritative, unless 'rebuild' or '[no]sync' was specified.
*/
- for (i = 0; i < rs->md.raid_disks; i++)
+ for (i = 0; i < rs->md.raid_disks; i++) {
set_bit(In_sync, &rs->dev[i].rdev.flags);
+ rs->dev[i].rdev.recovery_offset = MaxSector;
+ }
+ /*
+ * Second, parse the unordered optional arguments
+ */
for (i = 0; i < num_raid_params; i++) {
- if (!strcmp(argv[i], "nosync")) {
+ if (!strcasecmp(argv[i], "nosync")) {
rs->md.recovery_cp = MaxSector;
rs->print_flags |= DMPF_NOSYNC;
- rs->md.flags |= MD_SYNC_STATE_FORCED;
continue;
}
- if (!strcmp(argv[i], "sync")) {
+ if (!strcasecmp(argv[i], "sync")) {
rs->md.recovery_cp = 0;
rs->print_flags |= DMPF_SYNC;
- rs->md.flags |= MD_SYNC_STATE_FORCED;
continue;
}
@@ -300,9 +428,13 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
return -EINVAL;
}
- if (!strcmp(key, "rebuild")) {
- if (++rebuild_cnt > rs->raid_type->parity_devs) {
- rs->ti->error = "Too many rebuild drives given";
+ if (!strcasecmp(key, "rebuild")) {
+ rebuild_cnt++;
+ if (((rs->raid_type->level != 1) &&
+ (rebuild_cnt > rs->raid_type->parity_devs)) ||
+ ((rs->raid_type->level == 1) &&
+ (rebuild_cnt > (rs->md.raid_disks - 1)))) {
+ rs->ti->error = "Too many rebuild devices specified for given RAID type";
return -EINVAL;
}
if (value > rs->md.raid_disks) {
@@ -311,7 +443,22 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
}
clear_bit(In_sync, &rs->dev[value].rdev.flags);
rs->dev[value].rdev.recovery_offset = 0;
- } else if (!strcmp(key, "max_write_behind")) {
+ rs->print_flags |= DMPF_REBUILD;
+ } else if (!strcasecmp(key, "write_mostly")) {
+ if (rs->raid_type->level != 1) {
+ rs->ti->error = "write_mostly option is only valid for RAID1";
+ return -EINVAL;
+ }
+ if (value > rs->md.raid_disks) {
+ rs->ti->error = "Invalid write_mostly drive index given";
+ return -EINVAL;
+ }
+ set_bit(WriteMostly, &rs->dev[value].rdev.flags);
+ } else if (!strcasecmp(key, "max_write_behind")) {
+ if (rs->raid_type->level != 1) {
+ rs->ti->error = "max_write_behind option is only valid for RAID1";
+ return -EINVAL;
+ }
rs->print_flags |= DMPF_MAX_WRITE_BEHIND;
/*
@@ -324,14 +471,14 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
return -EINVAL;
}
rs->md.bitmap_info.max_write_behind = value;
- } else if (!strcmp(key, "daemon_sleep")) {
+ } else if (!strcasecmp(key, "daemon_sleep")) {
rs->print_flags |= DMPF_DAEMON_SLEEP;
if (!value || (value > MAX_SCHEDULE_TIMEOUT)) {
rs->ti->error = "daemon sleep period out of range";
return -EINVAL;
}
rs->md.bitmap_info.daemon_sleep = value;
- } else if (!strcmp(key, "stripe_cache")) {
+ } else if (!strcasecmp(key, "stripe_cache")) {
rs->print_flags |= DMPF_STRIPE_CACHE;
/*
@@ -348,20 +495,23 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
rs->ti->error = "Bad stripe_cache size";
return -EINVAL;
}
- } else if (!strcmp(key, "min_recovery_rate")) {
+ } else if (!strcasecmp(key, "min_recovery_rate")) {
rs->print_flags |= DMPF_MIN_RECOVERY_RATE;
if (value > INT_MAX) {
rs->ti->error = "min_recovery_rate out of range";
return -EINVAL;
}
rs->md.sync_speed_min = (int)value;
- } else if (!strcmp(key, "max_recovery_rate")) {
+ } else if (!strcasecmp(key, "max_recovery_rate")) {
rs->print_flags |= DMPF_MAX_RECOVERY_RATE;
if (value > INT_MAX) {
rs->ti->error = "max_recovery_rate out of range";
return -EINVAL;
}
rs->md.sync_speed_max = (int)value;
+ } else if (!strcasecmp(key, "region_size")) {
+ rs->print_flags |= DMPF_REGION_SIZE;
+ region_size = value;
} else {
DMERR("Unable to parse RAID parameter: %s", key);
rs->ti->error = "Unable to parse RAID parameters";
@@ -369,6 +519,19 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
}
}
+ if (validate_region_size(rs, region_size))
+ return -EINVAL;
+
+ if (rs->md.chunk_sectors)
+ rs->ti->split_io = rs->md.chunk_sectors;
+ else
+ rs->ti->split_io = region_size;
+
+ if (rs->md.chunk_sectors)
+ rs->ti->split_io = rs->md.chunk_sectors;
+ else
+ rs->ti->split_io = region_size;
+
/* Assume there are no metadata devices until the drives are parsed */
rs->md.persistent = 0;
rs->md.external = 1;
@@ -387,17 +550,351 @@ static int raid_is_congested(struct dm_target_callbacks *cb, int bits)
{
struct raid_set *rs = container_of(cb, struct raid_set, callbacks);
+ if (rs->raid_type->level == 1)
+ return md_raid1_congested(&rs->md, bits);
+
return md_raid5_congested(&rs->md, bits);
}
/*
+ * This structure is never routinely used by userspace, unlike md superblocks.
+ * Devices with this superblock should only ever be accessed via device-mapper.
+ */
+#define DM_RAID_MAGIC 0x64526D44
+struct dm_raid_superblock {
+ __le32 magic; /* "DmRd" */
+ __le32 features; /* Used to indicate possible future changes */
+
+ __le32 num_devices; /* Number of devices in this array. (Max 64) */
+ __le32 array_position; /* The position of this drive in the array */
+
+ __le64 events; /* Incremented by md when superblock updated */
+ __le64 failed_devices; /* Bit field of devices to indicate failures */
+
+ /*
+ * This offset tracks the progress of the repair or replacement of
+ * an individual drive.
+ */
+ __le64 disk_recovery_offset;
+
+ /*
+ * This offset tracks the progress of the initial array
+ * synchronisation/parity calculation.
+ */
+ __le64 array_resync_offset;
+
+ /*
+ * RAID characteristics
+ */
+ __le32 level;
+ __le32 layout;
+ __le32 stripe_sectors;
+
+ __u8 pad[452]; /* Round struct to 512 bytes. */
+ /* Always set to 0 when writing. */
+} __packed;
+
+static int read_disk_sb(mdk_rdev_t *rdev, int size)
+{
+ BUG_ON(!rdev->sb_page);
+
+ if (rdev->sb_loaded)
+ return 0;
+
+ if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, 1)) {
+ DMERR("Failed to read device superblock");
+ return -EINVAL;
+ }
+
+ rdev->sb_loaded = 1;
+
+ return 0;
+}
+
+static void super_sync(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+ mdk_rdev_t *r, *t;
+ uint64_t failed_devices;
+ struct dm_raid_superblock *sb;
+
+ sb = page_address(rdev->sb_page);
+ failed_devices = le64_to_cpu(sb->failed_devices);
+
+ rdev_for_each(r, t, mddev)
+ if ((r->raid_disk >= 0) && test_bit(Faulty, &r->flags))
+ failed_devices |= (1ULL << r->raid_disk);
+
+ memset(sb, 0, sizeof(*sb));
+
+ sb->magic = cpu_to_le32(DM_RAID_MAGIC);
+ sb->features = cpu_to_le32(0); /* No features yet */
+
+ sb->num_devices = cpu_to_le32(mddev->raid_disks);
+ sb->array_position = cpu_to_le32(rdev->raid_disk);
+
+ sb->events = cpu_to_le64(mddev->events);
+ sb->failed_devices = cpu_to_le64(failed_devices);
+
+ sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
+ sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
+
+ sb->level = cpu_to_le32(mddev->level);
+ sb->layout = cpu_to_le32(mddev->layout);
+ sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
+}
+
+/*
+ * super_load
+ *
+ * This function creates a superblock if one is not found on the device
+ * and will decide which superblock to use if there's a choice.
+ *
+ * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
+ */
+static int super_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev)
+{
+ int ret;
+ struct dm_raid_superblock *sb;
+ struct dm_raid_superblock *refsb;
+ uint64_t events_sb, events_refsb;
+
+ rdev->sb_start = 0;
+ rdev->sb_size = sizeof(*sb);
+
+ ret = read_disk_sb(rdev, rdev->sb_size);
+ if (ret)
+ return ret;
+
+ sb = page_address(rdev->sb_page);
+ if (sb->magic != cpu_to_le32(DM_RAID_MAGIC)) {
+ super_sync(rdev->mddev, rdev);
+
+ set_bit(FirstUse, &rdev->flags);
+
+ /* Force writing of superblocks to disk */
+ set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags);
+
+ /* Any superblock is better than none, choose that if given */
+ return refdev ? 0 : 1;
+ }
+
+ if (!refdev)
+ return 1;
+
+ events_sb = le64_to_cpu(sb->events);
+
+ refsb = page_address(refdev->sb_page);
+ events_refsb = le64_to_cpu(refsb->events);
+
+ return (events_sb > events_refsb) ? 1 : 0;
+}
+
+static int super_init_validation(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+ int role;
+ struct raid_set *rs = container_of(mddev, struct raid_set, md);
+ uint64_t events_sb;
+ uint64_t failed_devices;
+ struct dm_raid_superblock *sb;
+ uint32_t new_devs = 0;
+ uint32_t rebuilds = 0;
+ mdk_rdev_t *r, *t;
+ struct dm_raid_superblock *sb2;
+
+ sb = page_address(rdev->sb_page);
+ events_sb = le64_to_cpu(sb->events);
+ failed_devices = le64_to_cpu(sb->failed_devices);
+
+ /*
+ * Initialise to 1 if this is a new superblock.
+ */
+ mddev->events = events_sb ? : 1;
+
+ /*
+ * Reshaping is not currently allowed
+ */
+ if ((le32_to_cpu(sb->level) != mddev->level) ||
+ (le32_to_cpu(sb->layout) != mddev->layout) ||
+ (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors)) {
+ DMERR("Reshaping arrays not yet supported.");
+ return -EINVAL;
+ }
+
+ /* We can only change the number of devices in RAID1 right now */
+ if ((rs->raid_type->level != 1) &&
+ (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) {
+ DMERR("Reshaping arrays not yet supported.");
+ return -EINVAL;
+ }
+
+ if (!(rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC)))
+ mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
+
+ /*
+ * During load, we set FirstUse if a new superblock was written.
+ * There are two reasons we might not have a superblock:
+ * 1) The array is brand new - in which case, all of the
+ * devices must have their In_sync bit set. Also,
+ * recovery_cp must be 0, unless forced.
+ * 2) This is a new device being added to an old array
+ * and the new device needs to be rebuilt - in which
+ * case the In_sync bit will /not/ be set and
+ * recovery_cp must be MaxSector.
+ */
+ rdev_for_each(r, t, mddev) {
+ if (!test_bit(In_sync, &r->flags)) {
+ if (!test_bit(FirstUse, &r->flags))
+ DMERR("Superblock area of "
+ "rebuild device %d should have been "
+ "cleared.", r->raid_disk);
+ set_bit(FirstUse, &r->flags);
+ rebuilds++;
+ } else if (test_bit(FirstUse, &r->flags))
+ new_devs++;
+ }
+
+ if (!rebuilds) {
+ if (new_devs == mddev->raid_disks) {
+ DMINFO("Superblocks created for new array");
+ set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
+ } else if (new_devs) {
+ DMERR("New device injected "
+ "into existing array without 'rebuild' "
+ "parameter specified");
+ return -EINVAL;
+ }
+ } else if (new_devs) {
+ DMERR("'rebuild' devices cannot be "
+ "injected into an array with other first-time devices");
+ return -EINVAL;
+ } else if (mddev->recovery_cp != MaxSector) {
+ DMERR("'rebuild' specified while array is not in-sync");
+ return -EINVAL;
+ }
+
+ /*
+ * Now we set the Faulty bit for those devices that are
+ * recorded in the superblock as failed.
+ */
+ rdev_for_each(r, t, mddev) {
+ if (!r->sb_page)
+ continue;
+ sb2 = page_address(r->sb_page);
+ sb2->failed_devices = 0;
+
+ /*
+ * Check for any device re-ordering.
+ */
+ if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
+ role = le32_to_cpu(sb2->array_position);
+ if (role != r->raid_disk) {
+ if (rs->raid_type->level != 1) {
+ rs->ti->error = "Cannot change device "
+ "positions in RAID array";
+ return -EINVAL;
+ }
+ DMINFO("RAID1 device #%d now at position #%d",
+ role, r->raid_disk);
+ }
+
+ /*
+ * Partial recovery is performed on
+ * returning failed devices.
+ */
+ if (failed_devices & (1 << role))
+ set_bit(Faulty, &r->flags);
+ }
+ }
+
+ return 0;
+}
+
+static int super_validate(mddev_t *mddev, mdk_rdev_t *rdev)
+{
+ struct dm_raid_superblock *sb = page_address(rdev->sb_page);
+
+ /*
+ * If mddev->events is not set, we know we have not yet initialized
+ * the array.
+ */
+ if (!mddev->events && super_init_validation(mddev, rdev))
+ return -EINVAL;
+
+ mddev->bitmap_info.offset = 4096 >> 9; /* Enable bitmap creation */
+ rdev->mddev->bitmap_info.default_offset = 4096 >> 9;
+ if (!test_bit(FirstUse, &rdev->flags)) {
+ rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
+ if (rdev->recovery_offset != MaxSector)
+ clear_bit(In_sync, &rdev->flags);
+ }
+
+ /*
+ * If a device comes back, set it as not In_sync and no longer faulty.
+ */
+ if (test_bit(Faulty, &rdev->flags)) {
+ clear_bit(Faulty, &rdev->flags);
+ clear_bit(In_sync, &rdev->flags);
+ rdev->saved_raid_disk = rdev->raid_disk;
+ rdev->recovery_offset = 0;
+ }
+
+ clear_bit(FirstUse, &rdev->flags);
+
+ return 0;
+}
+
+/*
+ * Analyse superblocks and select the freshest.
+ */
+static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
+{
+ int ret;
+ mdk_rdev_t *rdev, *freshest, *tmp;
+ mddev_t *mddev = &rs->md;
+
+ freshest = NULL;
+ rdev_for_each(rdev, tmp, mddev) {
+ if (!rdev->meta_bdev)
+ continue;
+
+ ret = super_load(rdev, freshest);
+
+ switch (ret) {
+ case 1:
+ freshest = rdev;
+ break;
+ case 0:
+ break;
+ default:
+ ti->error = "Failed to load superblock";
+ return ret;
+ }
+ }
+
+ if (!freshest)
+ return 0;
+
+ /*
+ * Validation of the freshest device provides the source of
+ * validation for the remaining devices.
+ */
+ ti->error = "Unable to assemble array: Invalid superblocks";
+ if (super_validate(mddev, freshest))
+ return -EINVAL;
+
+ rdev_for_each(rdev, tmp, mddev)
+ if ((rdev != freshest) && super_validate(mddev, rdev))
+ return -EINVAL;
+
+ return 0;
+}
+
+/*
* Construct a RAID4/5/6 mapping:
* Args:
* <raid_type> <#raid_params> <raid_params> \
* <#raid_devs> { <meta_dev1> <dev1> .. <meta_devN> <devN> }
*
- * ** metadata devices are not supported yet, use '-' instead **
- *
* <raid_params> varies by <raid_type>. See 'parse_raid_params' for
* details on possible <raid_params>.
*/
@@ -465,8 +962,12 @@ static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv)
if (ret)
goto bad;
+ rs->md.sync_super = super_sync;
+ ret = analyse_superblocks(ti, rs);
+ if (ret)
+ goto bad;
+
INIT_WORK(&rs->md.event_work, do_table_event);
- ti->split_io = rs->md.chunk_sectors;
ti->private = rs;
mutex_lock(&rs->md.reconfig_mutex);
@@ -482,6 +983,7 @@ static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv)
rs->callbacks.congested_fn = raid_is_congested;
dm_table_add_target_callbacks(ti->table, &rs->callbacks);
+ mddev_suspend(&rs->md);
return 0;
bad:
@@ -546,12 +1048,17 @@ static int raid_status(struct dm_target *ti, status_type_t type,
break;
case STATUSTYPE_TABLE:
/* The string you would use to construct this array */
- for (i = 0; i < rs->md.raid_disks; i++)
- if (rs->dev[i].data_dev &&
+ for (i = 0; i < rs->md.raid_disks; i++) {
+ if ((rs->print_flags & DMPF_REBUILD) &&
+ rs->dev[i].data_dev &&
!test_bit(In_sync, &rs->dev[i].rdev.flags))
- raid_param_cnt++; /* for rebuilds */
+ raid_param_cnt += 2; /* for rebuilds */
+ if (rs->dev[i].data_dev &&
+ test_bit(WriteMostly, &rs->dev[i].rdev.flags))
+ raid_param_cnt += 2;
+ }
- raid_param_cnt += (hweight64(rs->print_flags) * 2);
+ raid_param_cnt += (hweight64(rs->print_flags & ~DMPF_REBUILD) * 2);
if (rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC))
raid_param_cnt--;
@@ -565,7 +1072,8 @@ static int raid_status(struct dm_target *ti, status_type_t type,
DMEMIT(" nosync");
for (i = 0; i < rs->md.raid_disks; i++)
- if (rs->dev[i].data_dev &&
+ if ((rs->print_flags & DMPF_REBUILD) &&
+ rs->dev[i].data_dev &&
!test_bit(In_sync, &rs->dev[i].rdev.flags))
DMEMIT(" rebuild %u", i);
@@ -579,6 +1087,11 @@ static int raid_status(struct dm_target *ti, status_type_t type,
if (rs->print_flags & DMPF_MAX_RECOVERY_RATE)
DMEMIT(" max_recovery_rate %d", rs->md.sync_speed_max);
+ for (i = 0; i < rs->md.raid_disks; i++)
+ if (rs->dev[i].data_dev &&
+ test_bit(WriteMostly, &rs->dev[i].rdev.flags))
+ DMEMIT(" write_mostly %u", i);
+
if (rs->print_flags & DMPF_MAX_WRITE_BEHIND)
DMEMIT(" max_write_behind %lu",
rs->md.bitmap_info.max_write_behind);
@@ -591,9 +1104,16 @@ static int raid_status(struct dm_target *ti, status_type_t type,
conf ? conf->max_nr_stripes * 2 : 0);
}
+ if (rs->print_flags & DMPF_REGION_SIZE)
+ DMEMIT(" region_size %lu",
+ rs->md.bitmap_info.chunksize >> 9);
+
DMEMIT(" %d", rs->md.raid_disks);
for (i = 0; i < rs->md.raid_disks; i++) {
- DMEMIT(" -"); /* metadata device */
+ if (rs->dev[i].meta_dev)
+ DMEMIT(" %s", rs->dev[i].meta_dev->name);
+ else
+ DMEMIT(" -");
if (rs->dev[i].data_dev)
DMEMIT(" %s", rs->dev[i].data_dev->name);
@@ -650,12 +1170,13 @@ static void raid_resume(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
+ bitmap_load(&rs->md);
mddev_resume(&rs->md);
}
static struct target_type raid_target = {
.name = "raid",
- .version = {1, 0, 0},
+ .version = {1, 1, 0},
.module = THIS_MODULE,
.ctr = raid_ctr,
.dtr = raid_dtr,
diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c
index 135c2f1fdbf..d1f1d701710 100644
--- a/drivers/md/dm-snap-persistent.c
+++ b/drivers/md/dm-snap-persistent.c
@@ -58,25 +58,30 @@
#define NUM_SNAPSHOT_HDR_CHUNKS 1
struct disk_header {
- uint32_t magic;
+ __le32 magic;
/*
* Is this snapshot valid. There is no way of recovering
* an invalid snapshot.
*/
- uint32_t valid;
+ __le32 valid;
/*
* Simple, incrementing version. no backward
* compatibility.
*/
- uint32_t version;
+ __le32 version;
/* In sectors */
- uint32_t chunk_size;
-};
+ __le32 chunk_size;
+} __packed;
struct disk_exception {
+ __le64 old_chunk;
+ __le64 new_chunk;
+} __packed;
+
+struct core_exception {
uint64_t old_chunk;
uint64_t new_chunk;
};
@@ -169,10 +174,9 @@ static int alloc_area(struct pstore *ps)
if (!ps->area)
goto err_area;
- ps->zero_area = vmalloc(len);
+ ps->zero_area = vzalloc(len);
if (!ps->zero_area)
goto err_zero_area;
- memset(ps->zero_area, 0, len);
ps->header_area = vmalloc(len);
if (!ps->header_area)
@@ -396,32 +400,32 @@ static struct disk_exception *get_exception(struct pstore *ps, uint32_t index)
}
static void read_exception(struct pstore *ps,
- uint32_t index, struct disk_exception *result)
+ uint32_t index, struct core_exception *result)
{
- struct disk_exception *e = get_exception(ps, index);
+ struct disk_exception *de = get_exception(ps, index);
/* copy it */
- result->old_chunk = le64_to_cpu(e->old_chunk);
- result->new_chunk = le64_to_cpu(e->new_chunk);
+ result->old_chunk = le64_to_cpu(de->old_chunk);
+ result->new_chunk = le64_to_cpu(de->new_chunk);
}
static void write_exception(struct pstore *ps,
- uint32_t index, struct disk_exception *de)
+ uint32_t index, struct core_exception *e)
{
- struct disk_exception *e = get_exception(ps, index);
+ struct disk_exception *de = get_exception(ps, index);
/* copy it */
- e->old_chunk = cpu_to_le64(de->old_chunk);
- e->new_chunk = cpu_to_le64(de->new_chunk);
+ de->old_chunk = cpu_to_le64(e->old_chunk);
+ de->new_chunk = cpu_to_le64(e->new_chunk);
}
static void clear_exception(struct pstore *ps, uint32_t index)
{
- struct disk_exception *e = get_exception(ps, index);
+ struct disk_exception *de = get_exception(ps, index);
/* clear it */
- e->old_chunk = 0;
- e->new_chunk = 0;
+ de->old_chunk = 0;
+ de->new_chunk = 0;
}
/*
@@ -437,13 +441,13 @@ static int insert_exceptions(struct pstore *ps,
{
int r;
unsigned int i;
- struct disk_exception de;
+ struct core_exception e;
/* presume the area is full */
*full = 1;
for (i = 0; i < ps->exceptions_per_area; i++) {
- read_exception(ps, i, &de);
+ read_exception(ps, i, &e);
/*
* If the new_chunk is pointing at the start of
@@ -451,7 +455,7 @@ static int insert_exceptions(struct pstore *ps,
* is we know that we've hit the end of the
* exceptions. Therefore the area is not full.
*/
- if (de.new_chunk == 0LL) {
+ if (e.new_chunk == 0LL) {
ps->current_committed = i;
*full = 0;
break;
@@ -460,13 +464,13 @@ static int insert_exceptions(struct pstore *ps,
/*
* Keep track of the start of the free chunks.
*/
- if (ps->next_free <= de.new_chunk)
- ps->next_free = de.new_chunk + 1;
+ if (ps->next_free <= e.new_chunk)
+ ps->next_free = e.new_chunk + 1;
/*
* Otherwise we add the exception to the snapshot.
*/
- r = callback(callback_context, de.old_chunk, de.new_chunk);
+ r = callback(callback_context, e.old_chunk, e.new_chunk);
if (r)
return r;
}
@@ -563,7 +567,7 @@ static int persistent_read_metadata(struct dm_exception_store *store,
ps->exceptions_per_area = (ps->store->chunk_size << SECTOR_SHIFT) /
sizeof(struct disk_exception);
ps->callbacks = dm_vcalloc(ps->exceptions_per_area,
- sizeof(*ps->callbacks));
+ sizeof(*ps->callbacks));
if (!ps->callbacks)
return -ENOMEM;
@@ -641,12 +645,12 @@ static void persistent_commit_exception(struct dm_exception_store *store,
{
unsigned int i;
struct pstore *ps = get_info(store);
- struct disk_exception de;
+ struct core_exception ce;
struct commit_callback *cb;
- de.old_chunk = e->old_chunk;
- de.new_chunk = e->new_chunk;
- write_exception(ps, ps->current_committed++, &de);
+ ce.old_chunk = e->old_chunk;
+ ce.new_chunk = e->new_chunk;
+ write_exception(ps, ps->current_committed++, &ce);
/*
* Add the callback to the back of the array. This code
@@ -670,7 +674,7 @@ static void persistent_commit_exception(struct dm_exception_store *store,
* If we completely filled the current area, then wipe the next one.
*/
if ((ps->current_committed == ps->exceptions_per_area) &&
- zero_disk_area(ps, ps->current_area + 1))
+ zero_disk_area(ps, ps->current_area + 1))
ps->valid = 0;
/*
@@ -701,7 +705,7 @@ static int persistent_prepare_merge(struct dm_exception_store *store,
chunk_t *last_new_chunk)
{
struct pstore *ps = get_info(store);
- struct disk_exception de;
+ struct core_exception ce;
int nr_consecutive;
int r;
@@ -722,9 +726,9 @@ static int persistent_prepare_merge(struct dm_exception_store *store,
ps->current_committed = ps->exceptions_per_area;
}
- read_exception(ps, ps->current_committed - 1, &de);
- *last_old_chunk = de.old_chunk;
- *last_new_chunk = de.new_chunk;
+ read_exception(ps, ps->current_committed - 1, &ce);
+ *last_old_chunk = ce.old_chunk;
+ *last_new_chunk = ce.new_chunk;
/*
* Find number of consecutive chunks within the current area,
@@ -733,9 +737,9 @@ static int persistent_prepare_merge(struct dm_exception_store *store,
for (nr_consecutive = 1; nr_consecutive < ps->current_committed;
nr_consecutive++) {
read_exception(ps, ps->current_committed - 1 - nr_consecutive,
- &de);
- if (de.old_chunk != *last_old_chunk - nr_consecutive ||
- de.new_chunk != *last_new_chunk - nr_consecutive)
+ &ce);
+ if (ce.old_chunk != *last_old_chunk - nr_consecutive ||
+ ce.new_chunk != *last_new_chunk - nr_consecutive)
break;
}
@@ -753,7 +757,7 @@ static int persistent_commit_merge(struct dm_exception_store *store,
for (i = 0; i < nr_merged; i++)
clear_exception(ps, ps->current_committed - 1 - i);
- r = area_io(ps, WRITE);
+ r = area_io(ps, WRITE_FLUSH_FUA);
if (r < 0)
return r;
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 9ecff5f3023..6f758870fc1 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -30,16 +30,6 @@ static const char dm_snapshot_merge_target_name[] = "snapshot-merge";
((ti)->type->name == dm_snapshot_merge_target_name)
/*
- * The percentage increment we will wake up users at
- */
-#define WAKE_UP_PERCENT 5
-
-/*
- * kcopyd priority of snapshot operations
- */
-#define SNAPSHOT_COPY_PRIORITY 2
-
-/*
* The size of the mempool used to track chunks in use.
*/
#define MIN_IOS 256
@@ -180,6 +170,13 @@ struct dm_snap_pending_exception {
* kcopyd.
*/
int started;
+
+ /*
+ * For writing a complete chunk, bypassing the copy.
+ */
+ struct bio *full_bio;
+ bio_end_io_t *full_bio_end_io;
+ void *full_bio_private;
};
/*
@@ -1055,8 +1052,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
s = kmalloc(sizeof(*s), GFP_KERNEL);
if (!s) {
- ti->error = "Cannot allocate snapshot context private "
- "structure";
+ ti->error = "Cannot allocate private snapshot structure";
r = -ENOMEM;
goto bad;
}
@@ -1380,6 +1376,7 @@ static void pending_complete(struct dm_snap_pending_exception *pe, int success)
struct dm_snapshot *s = pe->snap;
struct bio *origin_bios = NULL;
struct bio *snapshot_bios = NULL;
+ struct bio *full_bio = NULL;
int error = 0;
if (!success) {
@@ -1415,10 +1412,15 @@ static void pending_complete(struct dm_snap_pending_exception *pe, int success)
*/
dm_insert_exception(&s->complete, e);
- out:
+out:
dm_remove_exception(&pe->e);
snapshot_bios = bio_list_get(&pe->snapshot_bios);
origin_bios = bio_list_get(&pe->origin_bios);
+ full_bio = pe->full_bio;
+ if (full_bio) {
+ full_bio->bi_end_io = pe->full_bio_end_io;
+ full_bio->bi_private = pe->full_bio_private;
+ }
free_pending_exception(pe);
increment_pending_exceptions_done_count();
@@ -1426,10 +1428,15 @@ static void pending_complete(struct dm_snap_pending_exception *pe, int success)
up_write(&s->lock);
/* Submit any pending write bios */
- if (error)
+ if (error) {
+ if (full_bio)
+ bio_io_error(full_bio);
error_bios(snapshot_bios);
- else
+ } else {
+ if (full_bio)
+ bio_endio(full_bio, 0);
flush_bios(snapshot_bios);
+ }
retry_origin_bios(s, origin_bios);
}
@@ -1480,8 +1487,33 @@ static void start_copy(struct dm_snap_pending_exception *pe)
dest.count = src.count;
/* Hand over to kcopyd */
- dm_kcopyd_copy(s->kcopyd_client,
- &src, 1, &dest, 0, copy_callback, pe);
+ dm_kcopyd_copy(s->kcopyd_client, &src, 1, &dest, 0, copy_callback, pe);
+}
+
+static void full_bio_end_io(struct bio *bio, int error)
+{
+ void *callback_data = bio->bi_private;
+
+ dm_kcopyd_do_callback(callback_data, 0, error ? 1 : 0);
+}
+
+static void start_full_bio(struct dm_snap_pending_exception *pe,
+ struct bio *bio)
+{
+ struct dm_snapshot *s = pe->snap;
+ void *callback_data;
+
+ pe->full_bio = bio;
+ pe->full_bio_end_io = bio->bi_end_io;
+ pe->full_bio_private = bio->bi_private;
+
+ callback_data = dm_kcopyd_prepare_callback(s->kcopyd_client,
+ copy_callback, pe);
+
+ bio->bi_end_io = full_bio_end_io;
+ bio->bi_private = callback_data;
+
+ generic_make_request(bio);
}
static struct dm_snap_pending_exception *
@@ -1519,6 +1551,7 @@ __find_pending_exception(struct dm_snapshot *s,
bio_list_init(&pe->origin_bios);
bio_list_init(&pe->snapshot_bios);
pe->started = 0;
+ pe->full_bio = NULL;
if (s->store->type->prepare_exception(s->store, &pe->e)) {
free_pending_exception(pe);
@@ -1612,10 +1645,19 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio,
}
remap_exception(s, &pe->e, bio, chunk);
- bio_list_add(&pe->snapshot_bios, bio);
r = DM_MAPIO_SUBMITTED;
+ if (!pe->started &&
+ bio->bi_size == (s->store->chunk_size << SECTOR_SHIFT)) {
+ pe->started = 1;
+ up_write(&s->lock);
+ start_full_bio(pe, bio);
+ goto out;
+ }
+
+ bio_list_add(&pe->snapshot_bios, bio);
+
if (!pe->started) {
/* this is protected by snap->lock */
pe->started = 1;
@@ -1628,9 +1670,9 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio,
map_context->ptr = track_chunk(s, chunk);
}
- out_unlock:
+out_unlock:
up_write(&s->lock);
- out:
+out:
return r;
}
@@ -1974,7 +2016,7 @@ static int __origin_write(struct list_head *snapshots, sector_t sector,
pe_to_start_now = pe;
}
- next_snapshot:
+next_snapshot:
up_write(&snap->lock);
if (pe_to_start_now) {
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index bfe9c2333ce..986b8754bb0 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -54,7 +54,6 @@ struct dm_table {
sector_t *highs;
struct dm_target *targets;
- unsigned discards_supported:1;
unsigned integrity_supported:1;
/*
@@ -154,12 +153,11 @@ void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size)
return NULL;
size = nmemb * elem_size;
- addr = vmalloc(size);
- if (addr)
- memset(addr, 0, size);
+ addr = vzalloc(size);
return addr;
}
+EXPORT_SYMBOL(dm_vcalloc);
/*
* highs, and targets are managed as dynamic arrays during a
@@ -209,7 +207,6 @@ int dm_table_create(struct dm_table **result, fmode_t mode,
INIT_LIST_HEAD(&t->devices);
INIT_LIST_HEAD(&t->target_callbacks);
atomic_set(&t->holders, 0);
- t->discards_supported = 1;
if (!num_targets)
num_targets = KEYS_PER_NODE;
@@ -281,6 +278,7 @@ void dm_table_get(struct dm_table *t)
{
atomic_inc(&t->holders);
}
+EXPORT_SYMBOL(dm_table_get);
void dm_table_put(struct dm_table *t)
{
@@ -290,6 +288,7 @@ void dm_table_put(struct dm_table *t)
smp_mb__before_atomic_dec();
atomic_dec(&t->holders);
}
+EXPORT_SYMBOL(dm_table_put);
/*
* Checks to see if we need to extend highs or targets.
@@ -455,13 +454,14 @@ static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
* Add a device to the list, or just increment the usage count if
* it's already present.
*/
-static int __table_get_device(struct dm_table *t, struct dm_target *ti,
- const char *path, fmode_t mode, struct dm_dev **result)
+int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
+ struct dm_dev **result)
{
int r;
dev_t uninitialized_var(dev);
struct dm_dev_internal *dd;
unsigned int major, minor;
+ struct dm_table *t = ti->table;
BUG_ON(!t);
@@ -509,6 +509,7 @@ static int __table_get_device(struct dm_table *t, struct dm_target *ti,
*result = &dd->dm_dev;
return 0;
}
+EXPORT_SYMBOL(dm_get_device);
int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
sector_t start, sector_t len, void *data)
@@ -539,23 +540,15 @@ int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
* If not we'll force DM to use PAGE_SIZE or
* smaller I/O, just to be safe.
*/
-
- if (q->merge_bvec_fn && !ti->type->merge)
+ if (dm_queue_merge_is_compulsory(q) && !ti->type->merge)
blk_limits_max_hw_sectors(limits,
(unsigned int) (PAGE_SIZE >> 9));
return 0;
}
EXPORT_SYMBOL_GPL(dm_set_device_limits);
-int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
- struct dm_dev **result)
-{
- return __table_get_device(ti->table, ti, path, mode, result);
-}
-
-
/*
- * Decrement a devices use count and remove it if necessary.
+ * Decrement a device's use count and remove it if necessary.
*/
void dm_put_device(struct dm_target *ti, struct dm_dev *d)
{
@@ -568,6 +561,7 @@ void dm_put_device(struct dm_target *ti, struct dm_dev *d)
kfree(dd);
}
}
+EXPORT_SYMBOL(dm_put_device);
/*
* Checks to see if the target joins onto the end of the table.
@@ -791,8 +785,9 @@ int dm_table_add_target(struct dm_table *t, const char *type,
t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
- if (!tgt->num_discard_requests)
- t->discards_supported = 0;
+ if (!tgt->num_discard_requests && tgt->discards_supported)
+ DMWARN("%s: %s: ignoring discards_supported because num_discard_requests is zero.",
+ dm_device_name(t->md), type);
return 0;
@@ -802,6 +797,63 @@ int dm_table_add_target(struct dm_table *t, const char *type,
return r;
}
+/*
+ * Target argument parsing helpers.
+ */
+static int validate_next_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
+ unsigned *value, char **error, unsigned grouped)
+{
+ const char *arg_str = dm_shift_arg(arg_set);
+
+ if (!arg_str ||
+ (sscanf(arg_str, "%u", value) != 1) ||
+ (*value < arg->min) ||
+ (*value > arg->max) ||
+ (grouped && arg_set->argc < *value)) {
+ *error = arg->error;
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+int dm_read_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
+ unsigned *value, char **error)
+{
+ return validate_next_arg(arg, arg_set, value, error, 0);
+}
+EXPORT_SYMBOL(dm_read_arg);
+
+int dm_read_arg_group(struct dm_arg *arg, struct dm_arg_set *arg_set,
+ unsigned *value, char **error)
+{
+ return validate_next_arg(arg, arg_set, value, error, 1);
+}
+EXPORT_SYMBOL(dm_read_arg_group);
+
+const char *dm_shift_arg(struct dm_arg_set *as)
+{
+ char *r;
+
+ if (as->argc) {
+ as->argc--;
+ r = *as->argv;
+ as->argv++;
+ return r;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL(dm_shift_arg);
+
+void dm_consume_args(struct dm_arg_set *as, unsigned num_args)
+{
+ BUG_ON(as->argc < num_args);
+ as->argc -= num_args;
+ as->argv += num_args;
+}
+EXPORT_SYMBOL(dm_consume_args);
+
static int dm_table_set_type(struct dm_table *t)
{
unsigned i;
@@ -1077,11 +1129,13 @@ void dm_table_event(struct dm_table *t)
t->event_fn(t->event_context);
mutex_unlock(&_event_lock);
}
+EXPORT_SYMBOL(dm_table_event);
sector_t dm_table_get_size(struct dm_table *t)
{
return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0;
}
+EXPORT_SYMBOL(dm_table_get_size);
struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
{
@@ -1194,9 +1248,45 @@ static void dm_table_set_integrity(struct dm_table *t)
blk_get_integrity(template_disk));
}
+static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ unsigned flush = (*(unsigned *)data);
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && (q->flush_flags & flush);
+}
+
+static bool dm_table_supports_flush(struct dm_table *t, unsigned flush)
+{
+ struct dm_target *ti;
+ unsigned i = 0;
+
+ /*
+ * Require at least one underlying device to support flushes.
+ * t->devices includes internal dm devices such as mirror logs
+ * so we need to use iterate_devices here, which targets
+ * supporting flushes must provide.
+ */
+ while (i < dm_table_get_num_targets(t)) {
+ ti = dm_table_get_target(t, i++);
+
+ if (!ti->num_flush_requests)
+ continue;
+
+ if (ti->type->iterate_devices &&
+ ti->type->iterate_devices(ti, device_flush_capable, &flush))
+ return 1;
+ }
+
+ return 0;
+}
+
void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
struct queue_limits *limits)
{
+ unsigned flush = 0;
+
/*
* Copy table's limits to the DM device's request_queue
*/
@@ -1207,6 +1297,13 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
else
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
+ if (dm_table_supports_flush(t, REQ_FLUSH)) {
+ flush |= REQ_FLUSH;
+ if (dm_table_supports_flush(t, REQ_FUA))
+ flush |= REQ_FUA;
+ }
+ blk_queue_flush(q, flush);
+
dm_table_set_integrity(t);
/*
@@ -1237,6 +1334,7 @@ fmode_t dm_table_get_mode(struct dm_table *t)
{
return t->mode;
}
+EXPORT_SYMBOL(dm_table_get_mode);
static void suspend_targets(struct dm_table *t, unsigned postsuspend)
{
@@ -1345,6 +1443,7 @@ struct mapped_device *dm_table_get_md(struct dm_table *t)
{
return t->md;
}
+EXPORT_SYMBOL(dm_table_get_md);
static int device_discard_capable(struct dm_target *ti, struct dm_dev *dev,
sector_t start, sector_t len, void *data)
@@ -1359,19 +1458,19 @@ bool dm_table_supports_discards(struct dm_table *t)
struct dm_target *ti;
unsigned i = 0;
- if (!t->discards_supported)
- return 0;
-
/*
* Unless any target used by the table set discards_supported,
* require at least one underlying device to support discards.
* t->devices includes internal dm devices such as mirror logs
* so we need to use iterate_devices here, which targets
- * supporting discard must provide.
+ * supporting discard selectively must provide.
*/
while (i < dm_table_get_num_targets(t)) {
ti = dm_table_get_target(t, i++);
+ if (!ti->num_discard_requests)
+ continue;
+
if (ti->discards_supported)
return 1;
@@ -1382,13 +1481,3 @@ bool dm_table_supports_discards(struct dm_table *t)
return 0;
}
-
-EXPORT_SYMBOL(dm_vcalloc);
-EXPORT_SYMBOL(dm_get_device);
-EXPORT_SYMBOL(dm_put_device);
-EXPORT_SYMBOL(dm_table_event);
-EXPORT_SYMBOL(dm_table_get_size);
-EXPORT_SYMBOL(dm_table_get_mode);
-EXPORT_SYMBOL(dm_table_get_md);
-EXPORT_SYMBOL(dm_table_put);
-EXPORT_SYMBOL(dm_table_get);
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 0cf68b47887..52b39f335bb 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -37,6 +37,8 @@ static const char *_name = DM_NAME;
static unsigned int major = 0;
static unsigned int _major = 0;
+static DEFINE_IDR(_minor_idr);
+
static DEFINE_SPINLOCK(_minor_lock);
/*
* For bio-based dm.
@@ -109,6 +111,7 @@ EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo);
#define DMF_FREEING 3
#define DMF_DELETING 4
#define DMF_NOFLUSH_SUSPENDING 5
+#define DMF_MERGE_IS_OPTIONAL 6
/*
* Work processed by per-device workqueue.
@@ -313,6 +316,12 @@ static void __exit dm_exit(void)
while (i--)
_exits[i]();
+
+ /*
+ * Should be empty by this point.
+ */
+ idr_remove_all(&_minor_idr);
+ idr_destroy(&_minor_idr);
}
/*
@@ -1171,7 +1180,8 @@ static int __clone_and_map_discard(struct clone_info *ci)
/*
* Even though the device advertised discard support,
- * reconfiguration might have changed that since the
+ * that does not mean every target supports it, and
+ * reconfiguration might also have changed that since the
* check was performed.
*/
if (!ti->num_discard_requests)
@@ -1705,8 +1715,6 @@ static int dm_any_congested(void *congested_data, int bdi_bits)
/*-----------------------------------------------------------------
* An IDR is used to keep track of allocated minor numbers.
*---------------------------------------------------------------*/
-static DEFINE_IDR(_minor_idr);
-
static void free_minor(int minor)
{
spin_lock(&_minor_lock);
@@ -1800,7 +1808,6 @@ static void dm_init_md_queue(struct mapped_device *md)
blk_queue_make_request(md->queue, dm_request);
blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);
blk_queue_merge_bvec(md->queue, dm_merge_bvec);
- blk_queue_flush(md->queue, REQ_FLUSH | REQ_FUA);
}
/*
@@ -1986,6 +1993,59 @@ static void __set_size(struct mapped_device *md, sector_t size)
}
/*
+ * Return 1 if the queue has a compulsory merge_bvec_fn function.
+ *
+ * If this function returns 0, then the device is either a non-dm
+ * device without a merge_bvec_fn, or it is a dm device that is
+ * able to split any bios it receives that are too big.
+ */
+int dm_queue_merge_is_compulsory(struct request_queue *q)
+{
+ struct mapped_device *dev_md;
+
+ if (!q->merge_bvec_fn)
+ return 0;
+
+ if (q->make_request_fn == dm_request) {
+ dev_md = q->queuedata;
+ if (test_bit(DMF_MERGE_IS_OPTIONAL, &dev_md->flags))
+ return 0;
+ }
+
+ return 1;
+}
+
+static int dm_device_merge_is_compulsory(struct dm_target *ti,
+ struct dm_dev *dev, sector_t start,
+ sector_t len, void *data)
+{
+ struct block_device *bdev = dev->bdev;
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ return dm_queue_merge_is_compulsory(q);
+}
+
+/*
+ * Return 1 if it is acceptable to ignore merge_bvec_fn based
+ * on the properties of the underlying devices.
+ */
+static int dm_table_merge_is_optional(struct dm_table *table)
+{
+ unsigned i = 0;
+ struct dm_target *ti;
+
+ while (i < dm_table_get_num_targets(table)) {
+ ti = dm_table_get_target(table, i++);
+
+ if (ti->type->iterate_devices &&
+ ti->type->iterate_devices(ti, dm_device_merge_is_compulsory, NULL))
+ return 0;
+ }
+
+ return 1;
+}
+
+/*
* Returns old map, which caller must destroy.
*/
static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t,
@@ -1995,6 +2055,7 @@ static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t,
struct request_queue *q = md->queue;
sector_t size;
unsigned long flags;
+ int merge_is_optional;
size = dm_table_get_size(t);
@@ -2020,10 +2081,16 @@ static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t,
__bind_mempools(md, t);
+ merge_is_optional = dm_table_merge_is_optional(t);
+
write_lock_irqsave(&md->map_lock, flags);
old_map = md->map;
md->map = t;
dm_table_set_restrictions(t, q, limits);
+ if (merge_is_optional)
+ set_bit(DMF_MERGE_IS_OPTIONAL, &md->flags);
+ else
+ clear_bit(DMF_MERGE_IS_OPTIONAL, &md->flags);
write_unlock_irqrestore(&md->map_lock, flags);
return old_map;
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 1aaf16746da..6745dbd278a 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -66,6 +66,8 @@ int dm_table_alloc_md_mempools(struct dm_table *t);
void dm_table_free_md_mempools(struct dm_table *t);
struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
+int dm_queue_merge_is_compulsory(struct request_queue *q);
+
void dm_lock_md_type(struct mapped_device *md);
void dm_unlock_md_type(struct mapped_device *md);
void dm_set_md_type(struct mapped_device *md, unsigned type);
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 4427e045405..3fa1f3d90ce 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -208,6 +208,49 @@ struct dm_target_callbacks {
int dm_register_target(struct target_type *t);
void dm_unregister_target(struct target_type *t);
+/*
+ * Target argument parsing.
+ */
+struct dm_arg_set {
+ unsigned argc;
+ char **argv;
+};
+
+/*
+ * The minimum and maximum value of a numeric argument, together with
+ * the error message to use if the number is found to be outside that range.
+ */
+struct dm_arg {
+ unsigned min;
+ unsigned max;
+ char *error;
+};
+
+/*
+ * Validate the next argument, either returning it as *value or, if invalid,
+ * returning -EINVAL and setting *error.
+ */
+int dm_read_arg(struct dm_arg *arg, struct dm_arg_set *arg_set,
+ unsigned *value, char **error);
+
+/*
+ * Process the next argument as the start of a group containing between
+ * arg->min and arg->max further arguments. Either return the size as
+ * *num_args or, if invalid, return -EINVAL and set *error.
+ */
+int dm_read_arg_group(struct dm_arg *arg, struct dm_arg_set *arg_set,
+ unsigned *num_args, char **error);
+
+/*
+ * Return the current argument and shift to the next.
+ */
+const char *dm_shift_arg(struct dm_arg_set *as);
+
+/*
+ * Move through num_args arguments.
+ */
+void dm_consume_args(struct dm_arg_set *as, unsigned num_args);
+
/*-----------------------------------------------------------------
* Functions for creating and manipulating mapped devices.
* Drop the reference with dm_put when you finish with the object.
diff --git a/include/linux/dm-ioctl.h b/include/linux/dm-ioctl.h
index 3708455ee6c..0cb8eff76bd 100644
--- a/include/linux/dm-ioctl.h
+++ b/include/linux/dm-ioctl.h
@@ -267,9 +267,9 @@ enum {
#define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl)
#define DM_VERSION_MAJOR 4
-#define DM_VERSION_MINOR 20
+#define DM_VERSION_MINOR 21
#define DM_VERSION_PATCHLEVEL 0
-#define DM_VERSION_EXTRA "-ioctl (2011-02-02)"
+#define DM_VERSION_EXTRA "-ioctl (2011-07-06)"
/* Status bits */
#define DM_READONLY_FLAG (1 << 0) /* In/Out */
diff --git a/include/linux/dm-kcopyd.h b/include/linux/dm-kcopyd.h
index 298d587e349..5e54458e920 100644
--- a/include/linux/dm-kcopyd.h
+++ b/include/linux/dm-kcopyd.h
@@ -42,5 +42,20 @@ int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
unsigned num_dests, struct dm_io_region *dests,
unsigned flags, dm_kcopyd_notify_fn fn, void *context);
+/*
+ * Prepare a callback and submit it via the kcopyd thread.
+ *
+ * dm_kcopyd_prepare_callback allocates a callback structure and returns it.
+ * It must not be called from interrupt context.
+ * The returned value should be passed into dm_kcopyd_do_callback.
+ *
+ * dm_kcopyd_do_callback submits the callback.
+ * It may be called from interrupt context.
+ * The callback is issued from the kcopyd thread.
+ */
+void *dm_kcopyd_prepare_callback(struct dm_kcopyd_client *kc,
+ dm_kcopyd_notify_fn fn, void *context);
+void dm_kcopyd_do_callback(void *job, int read_err, unsigned long write_err);
+
#endif /* __KERNEL__ */
#endif /* _LINUX_DM_KCOPYD_H */