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:
  dm stripe: implement merge method
  dm mpath: allow table load with no priority groups
  dm mpath: fail message ioctl if specified path is not valid
  dm ioctl: add flag to wipe buffers for secure data
  dm ioctl: prepare for crypt key wiping
  dm crypt: wipe keys string immediately after key is set
  dm: add flakey target
  dm: fix opening log and cow devices for read only tables

11 files changed, 326 insertions, 31 deletions

diff --git a/Documentation/device-mapper/dm-flakey.txt b/Documentation/device-mapper/dm-flakey.txt
new file mode 100644
index 000000000000..c8efdfd19a65
--- /dev/null
+++ b/Documentation/device-mapper/dm-flakey.txt
@@ -0,0 +1,17 @@
+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.
+
+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.
+
+Parameters: <dev path> <offset> <up interval> <down interval>
+    <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.
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 98d9ec85e0eb..8420129fc5ee 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -327,4 +327,10 @@ config DM_UEVENT
         ---help---
         Generate udev events for DM events.
 
+config DM_FLAKEY
+       tristate "Flakey target (EXPERIMENTAL)"
+       depends on BLK_DEV_DM && EXPERIMENTAL
+       ---help---
+         A target that intermittently fails I/O for debugging purposes.
+
 endif # MD
diff --git a/drivers/md/Makefile b/drivers/md/Makefile
index d0138606c2e8..448838b1f92a 100644
--- a/drivers/md/Makefile
+++ b/drivers/md/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_BLK_DEV_MD)	+= md-mod.o
 obj-$(CONFIG_BLK_DEV_DM)        += dm-mod.o
 obj-$(CONFIG_DM_CRYPT)          += dm-crypt.o
 obj-$(CONFIG_DM_DELAY)          += dm-delay.o
+obj-$(CONFIG_DM_FLAKEY)         += dm-flakey.o
 obj-$(CONFIG_DM_MULTIPATH)      += dm-multipath.o dm-round-robin.o
 obj-$(CONFIG_DM_MULTIPATH_QL)   += dm-queue-length.o
 obj-$(CONFIG_DM_MULTIPATH_ST)   += dm-service-time.o
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 2c62c1169f78..c8827ffd85bb 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1324,20 +1324,29 @@ static int crypt_setkey_allcpus(struct crypt_config *cc)
 
 static int crypt_set_key(struct crypt_config *cc, char *key)
 {
+        int r = -EINVAL;
+        int key_string_len = strlen(key);
+
         /* The key size may not be changed. */
-        if (cc->key_size != (strlen(key) >> 1))
-                return -EINVAL;
+        if (cc->key_size != (key_string_len >> 1))
+                goto out;
 
         /* Hyphen (which gives a key_size of zero) means there is no key. */
         if (!cc->key_size && strcmp(key, "-"))
-                return -EINVAL;
+                goto out;
 
         if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0)
-                return -EINVAL;
+                goto out;
 
         set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
 
-        return crypt_setkey_allcpus(cc);
+        r = crypt_setkey_allcpus(cc);
+
+out:
+        /* Hex key string not needed after here, so wipe it. */
+        memset(key, '0', key_string_len);
+
+        return r;
 }
 
 static int crypt_wipe_key(struct crypt_config *cc)
diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
new file mode 100644
index 000000000000..ea790623c30b
--- /dev/null
+++ b/drivers/md/dm-flakey.c
@@ -0,0 +1,212 @@
+/*
+ * Copyright (C) 2003 Sistina Software (UK) Limited.
+ * Copyright (C) 2004, 2010 Red Hat, Inc. All rights reserved.
+ *
+ * This file is released under the GPL.
+ */
+
+#include <linux/device-mapper.h>
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/bio.h>
+#include <linux/slab.h>
+
+#define DM_MSG_PREFIX "flakey"
+
+/*
+ * Flakey: Used for testing only, simulates intermittent,
+ * catastrophic device failure.
+ */
+struct flakey_c {
+        struct dm_dev *dev;
+        unsigned long start_time;
+        sector_t start;
+        unsigned up_interval;
+        unsigned down_interval;
+};
+
+/*
+ * Construct a flakey mapping: <dev_path> <offset> <up interval> <down interval>
+ */
+static int flakey_ctr(struct dm_target *ti, unsigned int argc, char **argv)
+{
+        struct flakey_c *fc;
+        unsigned long long tmp;
+
+        if (argc != 4) {
+                ti->error = "dm-flakey: Invalid argument count";
+                return -EINVAL;
+        }
+
+        fc = kmalloc(sizeof(*fc), GFP_KERNEL);
+        if (!fc) {
+                ti->error = "dm-flakey: Cannot allocate linear context";
+                return -ENOMEM;
+        }
+        fc->start_time = jiffies;
+
+        if (sscanf(argv[1], "%llu", &tmp) != 1) {
+                ti->error = "dm-flakey: Invalid device sector";
+                goto bad;
+        }
+        fc->start = tmp;
+
+        if (sscanf(argv[2], "%u", &fc->up_interval) != 1) {
+                ti->error = "dm-flakey: Invalid up interval";
+                goto bad;
+        }
+
+        if (sscanf(argv[3], "%u", &fc->down_interval) != 1) {
+                ti->error = "dm-flakey: Invalid down interval";
+                goto bad;
+        }
+
+        if (!(fc->up_interval + fc->down_interval)) {
+                ti->error = "dm-flakey: Total (up + down) interval is zero";
+                goto bad;
+        }
+
+        if (fc->up_interval + fc->down_interval < fc->up_interval) {
+                ti->error = "dm-flakey: 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";
+                goto bad;
+        }
+
+        ti->num_flush_requests = 1;
+        ti->private = fc;
+        return 0;
+
+bad:
+        kfree(fc);
+        return -EINVAL;
+}
+
+static void flakey_dtr(struct dm_target *ti)
+{
+        struct flakey_c *fc = ti->private;
+
+        dm_put_device(ti, fc->dev);
+        kfree(fc);
+}
+
+static sector_t flakey_map_sector(struct dm_target *ti, sector_t bi_sector)
+{
+        struct flakey_c *fc = ti->private;
+
+        return fc->start + (bi_sector - ti->begin);
+}
+
+static void flakey_map_bio(struct dm_target *ti, struct bio *bio)
+{
+        struct flakey_c *fc = ti->private;
+
+        bio->bi_bdev = fc->dev->bdev;
+        if (bio_sectors(bio))
+                bio->bi_sector = flakey_map_sector(ti, bio->bi_sector);
+}
+
+static int flakey_map(struct dm_target *ti, struct bio *bio,
+                      union map_info *map_context)
+{
+        struct flakey_c *fc = ti->private;
+        unsigned elapsed;
+
+        /* Are we alive ? */
+        elapsed = (jiffies - fc->start_time) / HZ;
+        if (elapsed % (fc->up_interval + fc->down_interval) >= fc->up_interval)
+                return -EIO;
+
+        flakey_map_bio(ti, bio);
+
+        return DM_MAPIO_REMAPPED;
+}
+
+static int flakey_status(struct dm_target *ti, status_type_t type,
+                         char *result, unsigned int maxlen)
+{
+        struct flakey_c *fc = ti->private;
+
+        switch (type) {
+        case STATUSTYPE_INFO:
+                result[0] = '\0';
+                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);
+                break;
+        }
+        return 0;
+}
+
+static int flakey_ioctl(struct dm_target *ti, unsigned int cmd, unsigned long arg)
+{
+        struct flakey_c *fc = ti->private;
+
+        return __blkdev_driver_ioctl(fc->dev->bdev, fc->dev->mode, cmd, arg);
+}
+
+static int flakey_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
+                        struct bio_vec *biovec, int max_size)
+{
+        struct flakey_c *fc = ti->private;
+        struct request_queue *q = bdev_get_queue(fc->dev->bdev);
+
+        if (!q->merge_bvec_fn)
+                return max_size;
+
+        bvm->bi_bdev = fc->dev->bdev;
+        bvm->bi_sector = flakey_map_sector(ti, bvm->bi_sector);
+
+        return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
+}
+
+static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data)
+{
+        struct flakey_c *fc = ti->private;
+
+        return fn(ti, fc->dev, fc->start, ti->len, data);
+}
+
+static struct target_type flakey_target = {
+        .name   = "flakey",
+        .version = {1, 1, 0},
+        .module = THIS_MODULE,
+        .ctr    = flakey_ctr,
+        .dtr    = flakey_dtr,
+        .map    = flakey_map,
+        .status = flakey_status,
+        .ioctl  = flakey_ioctl,
+        .merge  = flakey_merge,
+        .iterate_devices = flakey_iterate_devices,
+};
+
+static int __init dm_flakey_init(void)
+{
+        int r = dm_register_target(&flakey_target);
+
+        if (r < 0)
+                DMERR("register failed %d", r);
+
+        return r;
+}
+
+static void __exit dm_flakey_exit(void)
+{
+        dm_unregister_target(&flakey_target);
+}
+
+/* Module hooks */
+module_init(dm_flakey_init);
+module_exit(dm_flakey_exit);
+
+MODULE_DESCRIPTION(DM_NAME " flakey target");
+MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 6d12775a1061..4cacdad2270a 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1501,14 +1501,10 @@ static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
         return r;
 }
 
-static void free_params(struct dm_ioctl *param)
-{
-        vfree(param);
-}
-
 static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param)
 {
         struct dm_ioctl tmp, *dmi;
+        int secure_data;
 
         if (copy_from_user(&tmp, user, sizeof(tmp) - sizeof(tmp.data)))
                 return -EFAULT;
@@ -1516,17 +1512,30 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param)
         if (tmp.data_size < (sizeof(tmp) - sizeof(tmp.data)))
                 return -EINVAL;
 
+        secure_data = tmp.flags & DM_SECURE_DATA_FLAG;
+
         dmi = vmalloc(tmp.data_size);
-        if (!dmi)
+        if (!dmi) {
+                if (secure_data && clear_user(user, tmp.data_size))
+                        return -EFAULT;
                 return -ENOMEM;
-
-        if (copy_from_user(dmi, user, tmp.data_size)) {
-                vfree(dmi);
-                return -EFAULT;
         }
 
+        if (copy_from_user(dmi, user, tmp.data_size))
+                goto bad;
+
+        /* Wipe the user buffer so we do not return it to userspace */
+        if (secure_data && clear_user(user, tmp.data_size))
+                goto bad;
+
         *param = dmi;
         return 0;
+
+bad:
+        if (secure_data)
+                memset(dmi, 0, tmp.data_size);
+        vfree(dmi);
+        return -EFAULT;
 }
 
 static int validate_params(uint cmd, struct dm_ioctl *param)
@@ -1534,6 +1543,7 @@ static int validate_params(uint cmd, struct dm_ioctl *param)
         /* Always clear this flag */
         param->flags &= ~DM_BUFFER_FULL_FLAG;
         param->flags &= ~DM_UEVENT_GENERATED_FLAG;
+        param->flags &= ~DM_SECURE_DATA_FLAG;
 
         /* Ignores parameters */
         if (cmd == DM_REMOVE_ALL_CMD ||
@@ -1561,10 +1571,11 @@ static int validate_params(uint cmd, struct dm_ioctl *param)
 static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
 {
         int r = 0;
+        int wipe_buffer;
         unsigned int cmd;
         struct dm_ioctl *uninitialized_var(param);
         ioctl_fn fn = NULL;
-        size_t param_size;
+        size_t input_param_size;
 
         /* only root can play with this */
         if (!capable(CAP_SYS_ADMIN))
@@ -1611,13 +1622,15 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
         if (r)
                 return r;
 
+        input_param_size = param->data_size;
+        wipe_buffer = param->flags & DM_SECURE_DATA_FLAG;
+
         r = validate_params(cmd, param);
         if (r)
                 goto out;
 
-        param_size = param->data_size;
         param->data_size = sizeof(*param);
-        r = fn(param, param_size);
+        r = fn(param, input_param_size);
 
         /*
          * Copy the results back to userland.
@@ -1625,8 +1638,11 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
         if (!r && copy_to_user(user, param, param->data_size))
                 r = -EFAULT;
 
- out:
-        free_params(param);
+out:
+        if (wipe_buffer)
+                memset(param, 0, input_param_size);
+
+        vfree(param);
         return r;
 }
 
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c
index 57968eb382c1..a1f321889676 100644
--- a/drivers/md/dm-log.c
+++ b/drivers/md/dm-log.c
@@ -543,7 +543,7 @@ static int disk_ctr(struct dm_dirty_log *log, struct dm_target *ti,
                 return -EINVAL;
         }
 
-        r = dm_get_device(ti, argv[0], FMODE_READ | FMODE_WRITE, &dev);
+        r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &dev);
         if (r)
                 return r;
 
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 4b0b63c290a6..a550a057d991 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -844,8 +844,8 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
 {
         /* target parameters */
         static struct param _params[] = {
-                {1, 1024, "invalid number of priority groups"},
-                {1, 1024, "invalid initial priority group number"},
+                {0, 1024, "invalid number of priority groups"},
+                {0, 1024, "invalid initial priority group number"},
         };
 
         int r;
@@ -879,6 +879,13 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
         if (r)
                 goto bad;
 
+        if ((!m->nr_priority_groups && next_pg_num) ||
+            (m->nr_priority_groups && !next_pg_num)) {
+                ti->error = "invalid initial priority group";
+                r = -EINVAL;
+                goto bad;
+        }
+
         /* parse the priority groups */
         while (as.argc) {
                 struct priority_group *pg;
@@ -1065,7 +1072,7 @@ out:
 static int action_dev(struct multipath *m, struct dm_dev *dev,
                       action_fn action)
 {
-        int r = 0;
+        int r = -EINVAL;
         struct pgpath *pgpath;
         struct priority_group *pg;
 
@@ -1415,7 +1422,7 @@ static int multipath_status(struct dm_target *ti, status_type_t type,
         else if (m->current_pg)
                 pg_num = m->current_pg->pg_num;
         else
-                        pg_num = 1;
+                pg_num = (m->nr_priority_groups ? 1 : 0);
 
         DMEMIT("%u ", pg_num);
 
@@ -1669,7 +1676,7 @@ out:
  *---------------------------------------------------------------*/
 static struct target_type multipath_target = {
         .name = "multipath",
-        .version = {1, 2, 0},
+        .version = {1, 3, 0},
         .module = THIS_MODULE,
         .ctr = multipath_ctr,
         .dtr = multipath_dtr,
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index fdde53cd12b7..a2d330942cb2 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -1080,7 +1080,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
         argv++;
         argc--;
 
-        r = dm_get_device(ti, cow_path, FMODE_READ | FMODE_WRITE, &s->cow);
+        r = dm_get_device(ti, cow_path, dm_table_get_mode(ti->table), &s->cow);
         if (r) {
                 ti->error = "Cannot get COW device";
                 goto bad_cow;
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index dddfa14f2982..3d80cf0c152d 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -396,9 +396,29 @@ static void stripe_io_hints(struct dm_target *ti,
         blk_limits_io_opt(limits, chunk_size * sc->stripes);
 }
 
+static int stripe_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
+                        struct bio_vec *biovec, int max_size)
+{
+        struct stripe_c *sc = ti->private;
+        sector_t bvm_sector = bvm->bi_sector;
+        uint32_t stripe;
+        struct request_queue *q;
+
+        stripe_map_sector(sc, bvm_sector, &stripe, &bvm_sector);
+
+        q = bdev_get_queue(sc->stripe[stripe].dev->bdev);
+        if (!q->merge_bvec_fn)
+                return max_size;
+
+        bvm->bi_bdev = sc->stripe[stripe].dev->bdev;
+        bvm->bi_sector = sc->stripe[stripe].physical_start + bvm_sector;
+
+        return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
+}
+
 static struct target_type stripe_target = {
         .name   = "striped",
-        .version = {1, 3, 1},
+        .version = {1, 4, 0},
         .module = THIS_MODULE,
         .ctr    = stripe_ctr,
         .dtr    = stripe_dtr,
@@ -407,6 +427,7 @@ static struct target_type stripe_target = {
         .status = stripe_status,
         .iterate_devices = stripe_iterate_devices,
         .io_hints = stripe_io_hints,
+        .merge  = stripe_merge,
 };
 
 int __init dm_stripe_init(void)
diff --git a/include/linux/dm-ioctl.h b/include/linux/dm-ioctl.h
index 78bbf47bbb96..3708455ee6c3 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        19
-#define DM_VERSION_PATCHLEVEL   1
-#define DM_VERSION_EXTRA        "-ioctl (2011-01-07)"
+#define DM_VERSION_MINOR        20
+#define DM_VERSION_PATCHLEVEL   0
+#define DM_VERSION_EXTRA        "-ioctl (2011-02-02)"
 
 /* Status bits */
 #define DM_READONLY_FLAG        (1 << 0) /* In/Out */
@@ -328,4 +328,10 @@ enum {
  */
 #define DM_UUID_FLAG                    (1 << 14) /* In */
 
+/*
+ * If set, all buffers are wiped after use. Use when sending
+ * or requesting sensitive data such as an encryption key.
+ */
+#define DM_SECURE_DATA_FLAG             (1 << 15) /* In */
+
 #endif                          /* _LINUX_DM_IOCTL_H */