diff options
Diffstat (limited to 'drivers/md/dm-ioctl.c')
| -rw-r--r-- | drivers/md/dm-ioctl.c | 114 |
1 files changed, 90 insertions, 24 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 0555b4410e05..e06f0ef7d2ec 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -23,6 +23,14 @@ #define DM_MSG_PREFIX "ioctl" #define DM_DRIVER_EMAIL "dm-devel@redhat.com" +struct dm_file { + /* + * poll will wait until the global event number is greater than + * this value. + */ + volatile unsigned global_event_nr; +}; + /*----------------------------------------------------------------- * The ioctl interface needs to be able to look up devices by * name or uuid. @@ -456,9 +464,9 @@ void dm_deferred_remove(void) * All the ioctl commands get dispatched to functions with this * prototype. */ -typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size); +typedef int (*ioctl_fn)(struct file *filp, struct dm_ioctl *param, size_t param_size); -static int remove_all(struct dm_ioctl *param, size_t param_size) +static int remove_all(struct file *filp, struct dm_ioctl *param, size_t param_size) { dm_hash_remove_all(true, !!(param->flags & DM_DEFERRED_REMOVE), false); param->data_size = 0; @@ -491,13 +499,14 @@ static void *get_result_buffer(struct dm_ioctl *param, size_t param_size, return ((void *) param) + param->data_start; } -static int list_devices(struct dm_ioctl *param, size_t param_size) +static int list_devices(struct file *filp, struct dm_ioctl *param, size_t param_size) { unsigned int i; struct hash_cell *hc; size_t len, needed = 0; struct gendisk *disk; struct dm_name_list *nl, *old_nl = NULL; + uint32_t *event_nr; down_write(&_hash_lock); @@ -510,6 +519,7 @@ static int list_devices(struct dm_ioctl *param, size_t param_size) needed += sizeof(struct dm_name_list); needed += strlen(hc->name) + 1; needed += ALIGN_MASK; + needed += (sizeof(uint32_t) + ALIGN_MASK) & ~ALIGN_MASK; } } @@ -539,7 +549,9 @@ static int list_devices(struct dm_ioctl *param, size_t param_size) strcpy(nl->name, hc->name); old_nl = nl; - nl = align_ptr(((void *) ++nl) + strlen(hc->name) + 1); + event_nr = align_ptr(((void *) (nl + 1)) + strlen(hc->name) + 1); + *event_nr = dm_get_event_nr(hc->md); + nl = align_ptr(event_nr + 1); } } @@ -582,7 +594,7 @@ static void list_version_get_info(struct target_type *tt, void *param) info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1); } -static int list_versions(struct dm_ioctl *param, size_t param_size) +static int list_versions(struct file *filp, struct dm_ioctl *param, size_t param_size) { size_t len, needed = 0; struct dm_target_versions *vers; @@ -724,7 +736,7 @@ static void __dev_status(struct mapped_device *md, struct dm_ioctl *param) } } -static int dev_create(struct dm_ioctl *param, size_t param_size) +static int dev_create(struct file *filp, struct dm_ioctl *param, size_t param_size) { int r, m = DM_ANY_MINOR; struct mapped_device *md; @@ -816,7 +828,7 @@ static struct mapped_device *find_device(struct dm_ioctl *param) return md; } -static int dev_remove(struct dm_ioctl *param, size_t param_size) +static int dev_remove(struct file *filp, struct dm_ioctl *param, size_t param_size) { struct hash_cell *hc; struct mapped_device *md; @@ -881,7 +893,7 @@ static int invalid_str(char *str, void *end) return -EINVAL; } -static int dev_rename(struct dm_ioctl *param, size_t param_size) +static int dev_rename(struct file *filp, struct dm_ioctl *param, size_t param_size) { int r; char *new_data = (char *) param + param->data_start; @@ -911,7 +923,7 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size) return 0; } -static int dev_set_geometry(struct dm_ioctl *param, size_t param_size) +static int dev_set_geometry(struct file *filp, struct dm_ioctl *param, size_t param_size) { int r = -EINVAL, x; struct mapped_device *md; @@ -1060,7 +1072,7 @@ static int do_resume(struct dm_ioctl *param) * Set or unset the suspension state of a device. * If the device already is in the requested state we just return its status. */ -static int dev_suspend(struct dm_ioctl *param, size_t param_size) +static int dev_suspend(struct file *filp, struct dm_ioctl *param, size_t param_size) { if (param->flags & DM_SUSPEND_FLAG) return do_suspend(param); @@ -1072,7 +1084,7 @@ static int dev_suspend(struct dm_ioctl *param, size_t param_size) * Copies device info back to user space, used by * the create and info ioctls. */ -static int dev_status(struct dm_ioctl *param, size_t param_size) +static int dev_status(struct file *filp, struct dm_ioctl *param, size_t param_size) { struct mapped_device *md; @@ -1163,7 +1175,7 @@ static void retrieve_status(struct dm_table *table, /* * Wait for a device to report an event */ -static int dev_wait(struct dm_ioctl *param, size_t param_size) +static int dev_wait(struct file *filp, struct dm_ioctl *param, size_t param_size) { int r = 0; struct mapped_device *md; @@ -1200,6 +1212,19 @@ out: return r; } +/* + * Remember the global event number and make it possible to poll + * for further events. + */ +static int dev_arm_poll(struct file *filp, struct dm_ioctl *param, size_t param_size) +{ + struct dm_file *priv = filp->private_data; + + priv->global_event_nr = atomic_read(&dm_global_event_nr); + + return 0; +} + static inline fmode_t get_mode(struct dm_ioctl *param) { fmode_t mode = FMODE_READ | FMODE_WRITE; @@ -1269,7 +1294,7 @@ static bool is_valid_type(enum dm_queue_mode cur, enum dm_queue_mode new) return false; } -static int table_load(struct dm_ioctl *param, size_t param_size) +static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_size) { int r; struct hash_cell *hc; @@ -1356,7 +1381,7 @@ err: return r; } -static int table_clear(struct dm_ioctl *param, size_t param_size) +static int table_clear(struct file *filp, struct dm_ioctl *param, size_t param_size) { struct hash_cell *hc; struct mapped_device *md; @@ -1430,7 +1455,7 @@ static void retrieve_deps(struct dm_table *table, param->data_size = param->data_start + needed; } -static int table_deps(struct dm_ioctl *param, size_t param_size) +static int table_deps(struct file *filp, struct dm_ioctl *param, size_t param_size) { struct mapped_device *md; struct dm_table *table; @@ -1456,7 +1481,7 @@ static int table_deps(struct dm_ioctl *param, size_t param_size) * Return the status of a device as a text string for each * target. */ -static int table_status(struct dm_ioctl *param, size_t param_size) +static int table_status(struct file *filp, struct dm_ioctl *param, size_t param_size) { struct mapped_device *md; struct dm_table *table; @@ -1511,7 +1536,7 @@ static int message_for_md(struct mapped_device *md, unsigned argc, char **argv, /* * Pass a message to the target that's at the supplied device offset. */ -static int target_message(struct dm_ioctl *param, size_t param_size) +static int target_message(struct file *filp, struct dm_ioctl *param, size_t param_size) { int r, argc; char **argv; @@ -1628,7 +1653,8 @@ static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags) {DM_LIST_VERSIONS_CMD, 0, list_versions}, {DM_TARGET_MSG_CMD, 0, target_message}, - {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry} + {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry}, + {DM_DEV_ARM_POLL, IOCTL_FLAGS_NO_PARAMS, dev_arm_poll}, }; if (unlikely(cmd >= ARRAY_SIZE(_ioctls))) @@ -1710,12 +1736,13 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kern } /* - * Try to avoid low memory issues when a device is suspended. + * Use __GFP_HIGH to avoid low memory issues when a device is + * suspended and the ioctl is needed to resume it. * Use kmalloc() rather than vmalloc() when we can. */ dmi = NULL; noio_flag = memalloc_noio_save(); - dmi = kvmalloc(param_kernel->data_size, GFP_KERNEL); + dmi = kvmalloc(param_kernel->data_size, GFP_KERNEL | __GFP_HIGH); memalloc_noio_restore(noio_flag); if (!dmi) { @@ -1782,7 +1809,7 @@ static int validate_params(uint cmd, struct dm_ioctl *param) return 0; } -static int ctl_ioctl(uint command, struct dm_ioctl __user *user) +static int ctl_ioctl(struct file *file, uint command, struct dm_ioctl __user *user) { int r = 0; int ioctl_flags; @@ -1836,7 +1863,7 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user) goto out; param->data_size = offsetof(struct dm_ioctl, data); - r = fn(param, input_param_size); + r = fn(file, param, input_param_size); if (unlikely(param->flags & DM_BUFFER_FULL_FLAG) && unlikely(ioctl_flags & IOCTL_FLAGS_NO_PARAMS)) @@ -1855,7 +1882,7 @@ out: static long dm_ctl_ioctl(struct file *file, uint command, ulong u) { - return (long)ctl_ioctl(command, (struct dm_ioctl __user *)u); + return (long)ctl_ioctl(file, command, (struct dm_ioctl __user *)u); } #ifdef CONFIG_COMPAT @@ -1867,8 +1894,47 @@ static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u) #define dm_compat_ctl_ioctl NULL #endif +static int dm_open(struct inode *inode, struct file *filp) +{ + int r; + struct dm_file *priv; + + r = nonseekable_open(inode, filp); + if (unlikely(r)) + return r; + + priv = filp->private_data = kmalloc(sizeof(struct dm_file), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->global_event_nr = atomic_read(&dm_global_event_nr); + + return 0; +} + +static int dm_release(struct inode *inode, struct file *filp) +{ + kfree(filp->private_data); + return 0; +} + +static unsigned dm_poll(struct file *filp, poll_table *wait) +{ + struct dm_file *priv = filp->private_data; + unsigned mask = 0; + + poll_wait(filp, &dm_global_eventq, wait); + + if ((int)(atomic_read(&dm_global_event_nr) - priv->global_event_nr) > 0) + mask |= POLLIN; + + return mask; +} + static const struct file_operations _ctl_fops = { - .open = nonseekable_open, + .open = dm_open, + .release = dm_release, + .poll = dm_poll, .unlocked_ioctl = dm_ctl_ioctl, .compat_ioctl = dm_compat_ctl_ioctl, .owner = THIS_MODULE, |