md: split md_set_readonly out of do_md_stop
[safe/jmp/linux-2.6] / drivers / md / dm-ioctl.c
index 4510ad8..d7500e1 100644 (file)
@@ -15,6 +15,7 @@
 #include <linux/slab.h>
 #include <linux/dm-ioctl.h>
 #include <linux/hdreg.h>
+#include <linux/compat.h>
 
 #include <asm/uaccess.h>
 
@@ -55,6 +56,11 @@ static void dm_hash_remove_all(int keep_open_devices);
  */
 static DECLARE_RWSEM(_hash_lock);
 
+/*
+ * Protects use of mdptr to obtain hash cell name and uuid from mapped device.
+ */
+static DEFINE_MUTEX(dm_hash_cells_mutex);
+
 static void init_buckets(struct list_head *buckets)
 {
        unsigned int i;
@@ -205,7 +211,9 @@ static int dm_hash_insert(const char *name, const char *uuid, struct mapped_devi
                list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid));
        }
        dm_get(md);
+       mutex_lock(&dm_hash_cells_mutex);
        dm_set_mdptr(md, cell);
+       mutex_unlock(&dm_hash_cells_mutex);
        up_write(&_hash_lock);
 
        return 0;
@@ -223,16 +231,18 @@ static void __hash_remove(struct hash_cell *hc)
        /* remove from the dev hash */
        list_del(&hc->uuid_list);
        list_del(&hc->name_list);
+       mutex_lock(&dm_hash_cells_mutex);
        dm_set_mdptr(hc->md, NULL);
+       mutex_unlock(&dm_hash_cells_mutex);
 
-       table = dm_get_table(hc->md);
+       table = dm_get_live_table(hc->md);
        if (table) {
                dm_table_event(table);
                dm_table_put(table);
        }
 
        if (hc->new_map)
-               dm_table_put(hc->new_map);
+               dm_table_destroy(hc->new_map);
        dm_put(hc->md);
        free_cell(hc);
 }
@@ -275,7 +285,8 @@ retry:
        up_write(&_hash_lock);
 }
 
-static int dm_hash_rename(const char *old, const char *new)
+static int dm_hash_rename(uint32_t cookie, uint32_t *flags, const char *old,
+                         const char *new)
 {
        char *new_name, *old_name;
        struct hash_cell *hc;
@@ -320,18 +331,23 @@ static int dm_hash_rename(const char *old, const char *new)
         */
        list_del(&hc->name_list);
        old_name = hc->name;
+       mutex_lock(&dm_hash_cells_mutex);
        hc->name = new_name;
+       mutex_unlock(&dm_hash_cells_mutex);
        list_add(&hc->name_list, _name_buckets + hash_str(new_name));
 
        /*
         * Wake up any dm event waiters.
         */
-       table = dm_get_table(hc->md);
+       table = dm_get_live_table(hc->md);
        if (table) {
                dm_table_event(table);
                dm_table_put(table);
        }
 
+       if (!dm_kobject_uevent(hc->md, KOBJ_CHANGE, cookie))
+               *flags |= DM_UEVENT_GENERATED_FLAG;
+
        dm_put(hc->md);
        up_write(&_hash_lock);
        kfree(old_name);
@@ -423,7 +439,7 @@ static int list_devices(struct dm_ioctl *param, size_t param_size)
                                old_nl->next = (uint32_t) ((void *) nl -
                                                           (void *) old_nl);
                        disk = dm_disk(hc->md);
-                       nl->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor));
+                       nl->dev = huge_encode_dev(disk_devt(disk));
                        nl->next = 0;
                        strcpy(nl->name, hc->name);
 
@@ -509,8 +525,6 @@ static int list_versions(struct dm_ioctl *param, size_t param_size)
        return 0;
 }
 
-
-
 static int check_name(const char *name)
 {
        if (strchr(name, '/')) {
@@ -522,6 +536,40 @@ static int check_name(const char *name)
 }
 
 /*
+ * On successful return, the caller must not attempt to acquire
+ * _hash_lock without first calling dm_table_put, because dm_table_destroy
+ * waits for this dm_table_put and could be called under this lock.
+ */
+static struct dm_table *dm_get_inactive_table(struct mapped_device *md)
+{
+       struct hash_cell *hc;
+       struct dm_table *table = NULL;
+
+       down_read(&_hash_lock);
+       hc = dm_get_mdptr(md);
+       if (!hc || hc->md != md) {
+               DMWARN("device has been removed from the dev hash table.");
+               goto out;
+       }
+
+       table = hc->new_map;
+       if (table)
+               dm_table_get(table);
+
+out:
+       up_read(&_hash_lock);
+
+       return table;
+}
+
+static struct dm_table *dm_get_live_or_inactive_table(struct mapped_device *md,
+                                                     struct dm_ioctl *param)
+{
+       return (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) ?
+               dm_get_inactive_table(md) : dm_get_live_table(md);
+}
+
+/*
  * Fills in a dm_ioctl structure, ready for sending back to
  * userland.
  */
@@ -533,10 +581,10 @@ static int __dev_status(struct mapped_device *md, struct dm_ioctl *param)
        param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
                          DM_ACTIVE_PRESENT_FLAG);
 
-       if (dm_suspended(md))
+       if (dm_suspended_md(md))
                param->flags |= DM_SUSPEND_FLAG;
 
-       param->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor));
+       param->dev = huge_encode_dev(disk_devt(disk));
 
        /*
         * Yes, this will be out of date by the time it gets back
@@ -545,18 +593,30 @@ static int __dev_status(struct mapped_device *md, struct dm_ioctl *param)
         */
        param->open_count = dm_open_count(md);
 
-       if (disk->policy)
-               param->flags |= DM_READONLY_FLAG;
-
        param->event_nr = dm_get_event_nr(md);
+       param->target_count = 0;
 
-       table = dm_get_table(md);
+       table = dm_get_live_table(md);
        if (table) {
-               param->flags |= DM_ACTIVE_PRESENT_FLAG;
-               param->target_count = dm_table_get_num_targets(table);
+               if (!(param->flags & DM_QUERY_INACTIVE_TABLE_FLAG)) {
+                       if (get_disk_ro(disk))
+                               param->flags |= DM_READONLY_FLAG;
+                       param->target_count = dm_table_get_num_targets(table);
+               }
                dm_table_put(table);
-       } else
-               param->target_count = 0;
+
+               param->flags |= DM_ACTIVE_PRESENT_FLAG;
+       }
+
+       if (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) {
+               table = dm_get_inactive_table(md);
+               if (table) {
+                       if (!(dm_table_get_mode(table) & FMODE_WRITE))
+                               param->flags |= DM_READONLY_FLAG;
+                       param->target_count = dm_table_get_num_targets(table);
+                       dm_table_put(table);
+               }
+       }
 
        return 0;
 }
@@ -631,9 +691,9 @@ static struct mapped_device *find_device(struct dm_ioctl *param)
                 * Sneakily write in both the name and the uuid
                 * while we have the cell.
                 */
-               strncpy(param->name, hc->name, sizeof(param->name));
+               strlcpy(param->name, hc->name, sizeof(param->name));
                if (hc->uuid)
-                       strncpy(param->uuid, hc->uuid, sizeof(param->uuid)-1);
+                       strlcpy(param->uuid, hc->uuid, sizeof(param->uuid));
                else
                        param->uuid[0] = '\0';
 
@@ -677,8 +737,11 @@ static int dev_remove(struct dm_ioctl *param, size_t param_size)
 
        __hash_remove(hc);
        up_write(&_hash_lock);
+
+       if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr))
+               param->flags |= DM_UEVENT_GENERATED_FLAG;
+
        dm_put(md);
-       param->data_size = 0;
        return 0;
 }
 
@@ -700,8 +763,9 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
        int r;
        char *new_name = (char *) param + param->data_start;
 
-       if (new_name < (char *) (param + 1) ||
-           invalid_str(new_name, (void *) param + param_size)) {
+       if (new_name < param->data ||
+           invalid_str(new_name, (void *) param + param_size) ||
+           strlen(new_name) > DM_NAME_LEN - 1) {
                DMWARN("Invalid new logical volume name supplied.");
                return -EINVAL;
        }
@@ -711,7 +775,9 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
                return r;
 
        param->data_size = 0;
-       return dm_hash_rename(param->name, new_name);
+
+       return dm_hash_rename(param->event_nr, &param->flags, param->name,
+                             new_name);
 }
 
 static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
@@ -726,7 +792,7 @@ static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
        if (!md)
                return -ENXIO;
 
-       if (geostr < (char *) (param + 1) ||
+       if (geostr < param->data ||
            invalid_str(geostr, (void *) param + param_size)) {
                DMWARN("Invalid geometry supplied.");
                goto out;
@@ -765,7 +831,7 @@ out:
 static int do_suspend(struct dm_ioctl *param)
 {
        int r = 0;
-       int do_lockfs = 1;
+       unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
        struct mapped_device *md;
 
        md = find_device(param);
@@ -773,10 +839,12 @@ static int do_suspend(struct dm_ioctl *param)
                return -ENXIO;
 
        if (param->flags & DM_SKIP_LOCKFS_FLAG)
-               do_lockfs = 0;
+               suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
+       if (param->flags & DM_NOFLUSH_FLAG)
+               suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
 
-       if (!dm_suspended(md))
-               r = dm_suspend(md, do_lockfs);
+       if (!dm_suspended_md(md))
+               r = dm_suspend(md, suspend_flags);
 
        if (!r)
                r = __dev_status(md, param);
@@ -788,10 +856,10 @@ static int do_suspend(struct dm_ioctl *param)
 static int do_resume(struct dm_ioctl *param)
 {
        int r = 0;
-       int do_lockfs = 1;
+       unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
        struct hash_cell *hc;
        struct mapped_device *md;
-       struct dm_table *new_map;
+       struct dm_table *new_map, *old_map = NULL;
 
        down_write(&_hash_lock);
 
@@ -814,27 +882,33 @@ static int do_resume(struct dm_ioctl *param)
        if (new_map) {
                /* Suspend if it isn't already suspended */
                if (param->flags & DM_SKIP_LOCKFS_FLAG)
-                       do_lockfs = 0;
-               if (!dm_suspended(md))
-                       dm_suspend(md, do_lockfs);
-
-               r = dm_swap_table(md, new_map);
-               if (r) {
+                       suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
+               if (param->flags & DM_NOFLUSH_FLAG)
+                       suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
+               if (!dm_suspended_md(md))
+                       dm_suspend(md, suspend_flags);
+
+               old_map = dm_swap_table(md, new_map);
+               if (IS_ERR(old_map)) {
+                       dm_table_destroy(new_map);
                        dm_put(md);
-                       dm_table_put(new_map);
-                       return r;
+                       return PTR_ERR(old_map);
                }
 
                if (dm_table_get_mode(new_map) & FMODE_WRITE)
                        set_disk_ro(dm_disk(md), 0);
                else
                        set_disk_ro(dm_disk(md), 1);
-
-               dm_table_put(new_map);
        }
 
-       if (dm_suspended(md))
+       if (dm_suspended_md(md)) {
                r = dm_resume(md);
+               if (!r && !dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr))
+                       param->flags |= DM_UEVENT_GENERATED_FLAG;
+       }
+
+       if (old_map)
+               dm_table_destroy(old_map);
 
        if (!r)
                r = __dev_status(md, param);
@@ -970,7 +1044,7 @@ static int dev_wait(struct dm_ioctl *param, size_t param_size)
        if (r)
                goto out;
 
-       table = dm_get_table(md);
+       table = dm_get_live_or_inactive_table(md, param);
        if (table) {
                retrieve_status(table, param, param_size);
                dm_table_put(table);
@@ -981,9 +1055,9 @@ static int dev_wait(struct dm_ioctl *param, size_t param_size)
        return r;
 }
 
-static inline int get_mode(struct dm_ioctl *param)
+static inline fmode_t get_mode(struct dm_ioctl *param)
 {
-       int mode = FMODE_READ | FMODE_WRITE;
+       fmode_t mode = FMODE_READ | FMODE_WRITE;
 
        if (param->flags & DM_READONLY_FLAG)
                mode = FMODE_READ;
@@ -1038,9 +1112,28 @@ static int populate_table(struct dm_table *table,
                next = spec->next;
        }
 
+       r = dm_table_set_type(table);
+       if (r) {
+               DMWARN("unable to set table type");
+               return r;
+       }
+
        return dm_table_complete(table);
 }
 
+static int table_prealloc_integrity(struct dm_table *t,
+                                   struct mapped_device *md)
+{
+       struct list_head *devices = dm_table_get_devices(t);
+       struct dm_dev_internal *dd;
+
+       list_for_each_entry(dd, devices, list)
+               if (bdev_get_integrity(dd->dm_dev.bdev))
+                       return blk_integrity_register(dm_disk(md), NULL);
+
+       return 0;
+}
+
 static int table_load(struct dm_ioctl *param, size_t param_size)
 {
        int r;
@@ -1058,7 +1151,22 @@ static int table_load(struct dm_ioctl *param, size_t param_size)
 
        r = populate_table(t, param, param_size);
        if (r) {
-               dm_table_put(t);
+               dm_table_destroy(t);
+               goto out;
+       }
+
+       r = table_prealloc_integrity(t, md);
+       if (r) {
+               DMERR("%s: could not register integrity profile.",
+                     dm_device_name(md));
+               dm_table_destroy(t);
+               goto out;
+       }
+
+       r = dm_table_alloc_md_mempools(t);
+       if (r) {
+               DMWARN("unable to allocate mempools for this table");
+               dm_table_destroy(t);
                goto out;
        }
 
@@ -1066,14 +1174,14 @@ static int table_load(struct dm_ioctl *param, size_t param_size)
        hc = dm_get_mdptr(md);
        if (!hc || hc->md != md) {
                DMWARN("device has been removed from the dev hash table.");
-               dm_table_put(t);
+               dm_table_destroy(t);
                up_write(&_hash_lock);
                r = -ENXIO;
                goto out;
        }
 
        if (hc->new_map)
-               dm_table_put(hc->new_map);
+               dm_table_destroy(hc->new_map);
        hc->new_map = t;
        up_write(&_hash_lock);
 
@@ -1102,7 +1210,7 @@ static int table_clear(struct dm_ioctl *param, size_t param_size)
        }
 
        if (hc->new_map) {
-               dm_table_put(hc->new_map);
+               dm_table_destroy(hc->new_map);
                hc->new_map = NULL;
        }
 
@@ -1124,7 +1232,7 @@ static void retrieve_deps(struct dm_table *table,
        unsigned int count = 0;
        struct list_head *tmp;
        size_t len, needed;
-       struct dm_dev *dd;
+       struct dm_dev_internal *dd;
        struct dm_target_deps *deps;
 
        deps = get_result_buffer(param, param_size, &len);
@@ -1150,7 +1258,7 @@ static void retrieve_deps(struct dm_table *table,
        deps->count = count;
        count = 0;
        list_for_each_entry (dd, dm_table_get_devices(table), list)
-               deps->dev[count++] = huge_encode_dev(dd->bdev->bd_dev);
+               deps->dev[count++] = huge_encode_dev(dd->dm_dev.bdev->bd_dev);
 
        param->data_size = param->data_start + needed;
 }
@@ -1169,7 +1277,7 @@ static int table_deps(struct dm_ioctl *param, size_t param_size)
        if (r)
                goto out;
 
-       table = dm_get_table(md);
+       table = dm_get_live_or_inactive_table(md, param);
        if (table) {
                retrieve_deps(table, param, param_size);
                dm_table_put(table);
@@ -1198,13 +1306,13 @@ static int table_status(struct dm_ioctl *param, size_t param_size)
        if (r)
                goto out;
 
-       table = dm_get_table(md);
+       table = dm_get_live_or_inactive_table(md, param);
        if (table) {
                retrieve_status(table, param, param_size);
                dm_table_put(table);
        }
 
- out:
+out:
        dm_put(md);
        return r;
 }
@@ -1229,7 +1337,7 @@ static int target_message(struct dm_ioctl *param, size_t param_size)
        if (r)
                goto out;
 
-       if (tmsg < (struct dm_target_msg *) (param + 1) ||
+       if (tmsg < (struct dm_target_msg *) param->data ||
            invalid_str(tmsg->message, (void *) param + param_size)) {
                DMWARN("Invalid target message parameters.");
                r = -EINVAL;
@@ -1242,18 +1350,20 @@ static int target_message(struct dm_ioctl *param, size_t param_size)
                goto out;
        }
 
-       table = dm_get_table(md);
+       table = dm_get_live_table(md);
        if (!table)
                goto out_argv;
 
-       if (tmsg->sector >= dm_table_get_size(table)) {
-               DMWARN("Target message sector outside device.");
-               r = -EINVAL;
+       if (dm_deleting_md(md)) {
+               r = -ENXIO;
                goto out_table;
        }
 
        ti = dm_table_find_target(table, tmsg->sector);
-       if (ti->type->message)
+       if (!dm_target_is_valid(ti)) {
+               DMWARN("Target message sector outside device.");
+               r = -EINVAL;
+       } else if (ti->type->message)
                r = ti->type->message(ti, argc, argv);
        else {
                DMWARN("Target type does not support messages");
@@ -1348,13 +1458,13 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param)
 {
        struct dm_ioctl tmp, *dmi;
 
-       if (copy_from_user(&tmp, user, sizeof(tmp)))
+       if (copy_from_user(&tmp, user, sizeof(tmp) - sizeof(tmp.data)))
                return -EFAULT;
 
-       if (tmp.data_size < sizeof(tmp))
+       if (tmp.data_size < (sizeof(tmp) - sizeof(tmp.data)))
                return -EINVAL;
 
-       dmi = (struct dm_ioctl *) vmalloc(tmp.data_size);
+       dmi = vmalloc(tmp.data_size);
        if (!dmi)
                return -ENOMEM;
 
@@ -1371,6 +1481,7 @@ 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;
 
        /* Ignores parameters */
        if (cmd == DM_REMOVE_ALL_CMD ||
@@ -1395,13 +1506,11 @@ static int validate_params(uint cmd, struct dm_ioctl *param)
        return 0;
 }
 
-static int ctl_ioctl(struct inode *inode, struct file *file,
-                    uint command, ulong u)
+static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
 {
        int r = 0;
        unsigned int cmd;
-       struct dm_ioctl *param;
-       struct dm_ioctl __user *user = (struct dm_ioctl __user *) u;
+       struct dm_ioctl *uninitialized_var(param);
        ioctl_fn fn = NULL;
        size_t param_size;
 
@@ -1469,14 +1578,30 @@ static int ctl_ioctl(struct inode *inode, struct file *file,
        return r;
 }
 
-static struct file_operations _ctl_fops = {
-       .ioctl   = ctl_ioctl,
+static long dm_ctl_ioctl(struct file *file, uint command, ulong u)
+{
+       return (long)ctl_ioctl(command, (struct dm_ioctl __user *)u);
+}
+
+#ifdef CONFIG_COMPAT
+static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u)
+{
+       return (long)dm_ctl_ioctl(file, command, (ulong) compat_ptr(u));
+}
+#else
+#define dm_compat_ctl_ioctl NULL
+#endif
+
+static const struct file_operations _ctl_fops = {
+       .unlocked_ioctl  = dm_ctl_ioctl,
+       .compat_ioctl = dm_compat_ctl_ioctl,
        .owner   = THIS_MODULE,
 };
 
 static struct miscdevice _dm_misc = {
        .minor          = MISC_DYNAMIC_MINOR,
        .name           = DM_NAME,
+       .nodename       = "mapper/control",
        .fops           = &_ctl_fops
 };
 
@@ -1511,3 +1636,35 @@ void dm_interface_exit(void)
 
        dm_hash_exit();
 }
+
+/**
+ * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
+ * @md: Pointer to mapped_device
+ * @name: Buffer (size DM_NAME_LEN) for name
+ * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
+ */
+int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
+{
+       int r = 0;
+       struct hash_cell *hc;
+
+       if (!md)
+               return -ENXIO;
+
+       mutex_lock(&dm_hash_cells_mutex);
+       hc = dm_get_mdptr(md);
+       if (!hc || hc->md != md) {
+               r = -ENXIO;
+               goto out;
+       }
+
+       if (name)
+               strcpy(name, hc->name);
+       if (uuid)
+               strcpy(uuid, hc->uuid ? : "");
+
+out:
+       mutex_unlock(&dm_hash_cells_mutex);
+
+       return r;
+}