Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262382AbTGAOwt (ORCPT ); Tue, 1 Jul 2003 10:52:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262366AbTGAOws (ORCPT ); Tue, 1 Jul 2003 10:52:48 -0400 Received: from mrburns.nildram.co.uk ([195.112.4.54]:39686 "EHLO mrburns.nildram.co.uk") by vger.kernel.org with ESMTP id S262382AbTGAOs2 (ORCPT ); Tue, 1 Jul 2003 10:48:28 -0400 Date: Tue, 1 Jul 2003 16:02:46 +0100 From: Joe Thornber To: Joe Thornber Cc: Linux Mailing List , dm-devel@sistina.com Subject: [RFC 3/3] dm: v4 ioctl interface Message-ID: <20030701150246.GD1596@fib011235813.fsnet.co.uk> References: <20030701145812.GA1596@fib011235813.fsnet.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030701145812.GA1596@fib011235813.fsnet.co.uk> User-Agent: Mutt/1.5.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 96456 Lines: 4256 v4 of the ioctl interface. Note there never was a v2 or a v3 except in an unofficial EVMS way. There is now a config option to allow the user to select v1 or v4, it defaults to v1. If you want to use v4 you will have to update your tools (libdevmapper/lvm), these new tools have not been released at the time of writing. dm-ioctl.[hc] just #includes dm-ioctl-v[14].[hc] depending on the config option. --- diff/drivers/md/Kconfig 2003-05-21 11:50:15.000000000 +0100 +++ source/drivers/md/Kconfig 2003-07-01 15:36:42.000000000 +0100 @@ -145,5 +145,12 @@ If unsure, say N. +config DM_IOCTL_V4 + bool "ioctl interface version 4" + depends on BLK_DEV_DM + ---help--- + Recent tools use a new version of the ioctl interface, only + select this option if you intend using such tools. + endmenu --- diff/drivers/md/dm-ioctl.c 2003-06-30 17:12:49.000000000 +0100 +++ source/drivers/md/dm-ioctl.c 2003-07-01 15:36:42.000000000 +0100 @@ -1,1133 +1,13 @@ /* - * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. + * Copyright (C) 2003 Sistina Software (UK) Limited. * * This file is released under the GPL. */ -#include "dm.h" - -#include -#include -#include #include -#include -#include -#include -#include -#include - -#include - -#define DM_DRIVER_EMAIL "dm@uk.sistina.com" - -/*----------------------------------------------------------------- - * The ioctl interface needs to be able to look up devices by - * name or uuid. - *---------------------------------------------------------------*/ -struct hash_cell { - struct list_head name_list; - struct list_head uuid_list; - - char *name; - char *uuid; - struct mapped_device *md; -}; - -#define NUM_BUCKETS 64 -#define MASK_BUCKETS (NUM_BUCKETS - 1) -static struct list_head _name_buckets[NUM_BUCKETS]; -static struct list_head _uuid_buckets[NUM_BUCKETS]; - -void dm_hash_remove_all(void); - -/* - * Guards access to all three tables. - */ -static DECLARE_RWSEM(_hash_lock); - -static void init_buckets(struct list_head *buckets) -{ - unsigned int i; - - for (i = 0; i < NUM_BUCKETS; i++) - INIT_LIST_HEAD(buckets + i); -} - -int dm_hash_init(void) -{ - init_buckets(_name_buckets); - init_buckets(_uuid_buckets); - devfs_mk_dir(DM_DIR); - return 0; -} - -void dm_hash_exit(void) -{ - dm_hash_remove_all(); - devfs_remove(DM_DIR); -} - -/*----------------------------------------------------------------- - * Hash function: - * We're not really concerned with the str hash function being - * fast since it's only used by the ioctl interface. - *---------------------------------------------------------------*/ -static unsigned int hash_str(const char *str) -{ - const unsigned int hash_mult = 2654435387U; - unsigned int h = 0; - - while (*str) - h = (h + (unsigned int) *str++) * hash_mult; - - return h & MASK_BUCKETS; -} - -/*----------------------------------------------------------------- - * Code for looking up a device by name - *---------------------------------------------------------------*/ -static struct hash_cell *__get_name_cell(const char *str) -{ - struct list_head *tmp; - struct hash_cell *hc; - unsigned int h = hash_str(str); - - list_for_each (tmp, _name_buckets + h) { - hc = list_entry(tmp, struct hash_cell, name_list); - if (!strcmp(hc->name, str)) - return hc; - } - - return NULL; -} - -static struct hash_cell *__get_uuid_cell(const char *str) -{ - struct list_head *tmp; - struct hash_cell *hc; - unsigned int h = hash_str(str); - - list_for_each (tmp, _uuid_buckets + h) { - hc = list_entry(tmp, struct hash_cell, uuid_list); - if (!strcmp(hc->uuid, str)) - return hc; - } - - return NULL; -} - -/*----------------------------------------------------------------- - * Inserting, removing and renaming a device. - *---------------------------------------------------------------*/ -static inline char *kstrdup(const char *str) -{ - char *r = kmalloc(strlen(str) + 1, GFP_KERNEL); - if (r) - strcpy(r, str); - return r; -} - -static struct hash_cell *alloc_cell(const char *name, const char *uuid, - struct mapped_device *md) -{ - struct hash_cell *hc; - - hc = kmalloc(sizeof(*hc), GFP_KERNEL); - if (!hc) - return NULL; - - hc->name = kstrdup(name); - if (!hc->name) { - kfree(hc); - return NULL; - } - - if (!uuid) - hc->uuid = NULL; - - else { - hc->uuid = kstrdup(uuid); - if (!hc->uuid) { - kfree(hc->name); - kfree(hc); - return NULL; - } - } - - INIT_LIST_HEAD(&hc->name_list); - INIT_LIST_HEAD(&hc->uuid_list); - hc->md = md; - return hc; -} - -static void free_cell(struct hash_cell *hc) -{ - if (hc) { - kfree(hc->name); - kfree(hc->uuid); - kfree(hc); - } -} - -/* - * devfs stuff. - */ -static int register_with_devfs(struct hash_cell *hc) -{ - struct gendisk *disk = dm_disk(hc->md); - - devfs_mk_bdev(MKDEV(disk->major, disk->first_minor), - S_IFBLK | S_IRUSR | S_IWUSR | S_IRGRP, - DM_DIR "/%s", hc->name); - return 0; -} - -static int unregister_with_devfs(struct hash_cell *hc) -{ - devfs_remove(DM_DIR"/%s", hc->name); - return 0; -} - -/* - * The kdev_t and uuid of a device can never change once it is - * initially inserted. - */ -int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md) -{ - struct hash_cell *cell; - - /* - * Allocate the new cells. - */ - cell = alloc_cell(name, uuid, md); - if (!cell) - return -ENOMEM; - - /* - * Insert the cell into all three hash tables. - */ - down_write(&_hash_lock); - if (__get_name_cell(name)) - goto bad; - - list_add(&cell->name_list, _name_buckets + hash_str(name)); - - if (uuid) { - if (__get_uuid_cell(uuid)) { - list_del(&cell->name_list); - goto bad; - } - list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid)); - } - register_with_devfs(cell); - dm_get(md); - up_write(&_hash_lock); - - return 0; - - bad: - up_write(&_hash_lock); - free_cell(cell); - return -EBUSY; -} - -void __hash_remove(struct hash_cell *hc) -{ - /* remove from the dev hash */ - list_del(&hc->uuid_list); - list_del(&hc->name_list); - unregister_with_devfs(hc); - dm_put(hc->md); - free_cell(hc); -} - -void dm_hash_remove_all(void) -{ - int i; - struct hash_cell *hc; - struct list_head *tmp, *n; - - down_write(&_hash_lock); - for (i = 0; i < NUM_BUCKETS; i++) { - list_for_each_safe (tmp, n, _name_buckets + i) { - hc = list_entry(tmp, struct hash_cell, name_list); - __hash_remove(hc); - } - } - up_write(&_hash_lock); -} - -int dm_hash_rename(const char *old, const char *new) -{ - char *new_name, *old_name; - struct hash_cell *hc; - - /* - * duplicate new. - */ - new_name = kstrdup(new); - if (!new_name) - return -ENOMEM; - - down_write(&_hash_lock); - - /* - * Is new free ? - */ - hc = __get_name_cell(new); - if (hc) { - DMWARN("asked to rename to an already existing name %s -> %s", - old, new); - up_write(&_hash_lock); - kfree(new_name); - return -EBUSY; - } - - /* - * Is there such a device as 'old' ? - */ - hc = __get_name_cell(old); - if (!hc) { - DMWARN("asked to rename a non existent device %s -> %s", - old, new); - up_write(&_hash_lock); - kfree(new_name); - return -ENXIO; - } - - /* - * rename and move the name cell. - */ - unregister_with_devfs(hc); - - list_del(&hc->name_list); - old_name = hc->name; - hc->name = new_name; - list_add(&hc->name_list, _name_buckets + hash_str(new_name)); - - /* rename the device node in devfs */ - register_with_devfs(hc); - - up_write(&_hash_lock); - kfree(old_name); - return 0; -} - - -/*----------------------------------------------------------------- - * Implementation of the ioctl commands - *---------------------------------------------------------------*/ - -/* - * All the ioctl commands get dispatched to functions with this - * prototype. - */ -typedef int (*ioctl_fn)(struct dm_ioctl *param, struct dm_ioctl *user); - -/* - * Check a string doesn't overrun the chunk of - * memory we copied from userland. - */ -static int valid_str(char *str, void *begin, void *end) -{ - while (((void *) str >= begin) && ((void *) str < end)) - if (!*str++) - return 0; - - return -EINVAL; -} - -static int next_target(struct dm_target_spec *last, uint32_t next, - void *begin, void *end, - struct dm_target_spec **spec, char **params) -{ - *spec = (struct dm_target_spec *) - ((unsigned char *) last + next); - *params = (char *) (*spec + 1); - - if (*spec < (last + 1) || ((void *) *spec > end)) - return -EINVAL; - - return valid_str(*params, begin, end); -} - -static int populate_table(struct dm_table *table, struct dm_ioctl *args) -{ - int r, first = 1; - unsigned int i = 0; - struct dm_target_spec *spec; - char *params; - void *begin, *end; - - if (!args->target_count) { - DMWARN("populate_table: no targets specified"); - return -EINVAL; - } - - begin = (void *) args; - end = begin + args->data_size; - - for (i = 0; i < args->target_count; i++) { - - if (first) - r = next_target((struct dm_target_spec *) args, - args->data_start, - begin, end, &spec, ¶ms); - else - r = next_target(spec, spec->next, begin, end, - &spec, ¶ms); - - if (r) { - DMWARN("unable to find target"); - return -EINVAL; - } - - r = dm_table_add_target(table, spec->target_type, - (sector_t) spec->sector_start, - (sector_t) spec->length, - params); - if (r) { - DMWARN("internal error adding target to table"); - return -EINVAL; - } - - first = 0; - } - - return dm_table_complete(table); -} - -/* - * Round up the ptr to the next 'align' boundary. Obviously - * 'align' must be a power of 2. - */ -static inline void *align_ptr(void *ptr, unsigned int align) -{ - align--; - return (void *) (((unsigned long) (ptr + align)) & ~align); -} - -/* - * Copies a dm_ioctl and an optional additional payload to - * userland. - */ -static int results_to_user(struct dm_ioctl *user, struct dm_ioctl *param, - void *data, uint32_t len) -{ - int r; - void *ptr = NULL; - - if (data) { - ptr = align_ptr(user + 1, sizeof(unsigned long)); - param->data_start = ptr - (void *) user; - } - - /* - * The version number has already been filled in, so we - * just copy later fields. - */ - r = copy_to_user(&user->data_size, ¶m->data_size, - sizeof(*param) - sizeof(param->version)); - if (r) - return -EFAULT; - - if (data) { - if (param->data_start + len > param->data_size) - return -ENOSPC; - - if (copy_to_user(ptr, data, len)) - r = -EFAULT; - } - - return r; -} - -/* - * Fills in a dm_ioctl structure, ready for sending back to - * userland. - */ -static int __info(struct mapped_device *md, struct dm_ioctl *param) -{ - struct dm_table *table; - struct block_device *bdev; - struct gendisk *disk = dm_disk(md); - - param->flags = DM_EXISTS_FLAG; - if (dm_suspended(md)) - param->flags |= DM_SUSPEND_FLAG; - - bdev = bdget_disk(disk, 0); - if (!bdev) - return -ENXIO; - - param->dev = bdev->bd_dev; - param->open_count = bdev->bd_openers; - bdput(bdev); - - if (disk->policy) - param->flags |= DM_READONLY_FLAG; - - table = dm_get_table(md); - param->target_count = dm_table_get_num_targets(table); - dm_table_put(table); - - return 0; -} - -/* - * Always use UUID for lookups if it's present, otherwise use name. - */ -static inline struct mapped_device *find_device(struct dm_ioctl *param) -{ - struct hash_cell *hc; - struct mapped_device *md = NULL; - - down_read(&_hash_lock); - hc = *param->uuid ? __get_uuid_cell(param->uuid) : - __get_name_cell(param->name); - 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'; - - dm_get(md); - } - up_read(&_hash_lock); - - return md; -} - -#define ALIGNMENT sizeof(int) -static void *_align(void *ptr, unsigned int a) -{ - register unsigned long align = --a; - - return (void *) (((unsigned long) ptr + align) & ~align); -} - -/* - * Copies device info back to user space, used by - * the create and info ioctls. - */ -static int info(struct dm_ioctl *param, struct dm_ioctl *user) -{ - struct mapped_device *md; - - param->flags = 0; - - md = find_device(param); - if (!md) - /* - * Device not found - returns cleared exists flag. - */ - goto out; - - __info(md, param); - dm_put(md); - - out: - return results_to_user(user, param, NULL, 0); -} - -static inline int get_mode(struct dm_ioctl *param) -{ - int mode = FMODE_READ | FMODE_WRITE; - - if (param->flags & DM_READONLY_FLAG) - mode = FMODE_READ; - - return mode; -} - -static int check_name(const char *name) -{ - if (name[0] == '/') { - DMWARN("invalid device name"); - return -EINVAL; - } - - return 0; -} - -static int create(struct dm_ioctl *param, struct dm_ioctl *user) -{ - int r; - struct dm_table *t; - struct mapped_device *md; - - r = check_name(param->name); - if (r) - return r; - - r = dm_table_create(&t, get_mode(param)); - if (r) - return r; - - r = populate_table(t, param); - if (r) { - dm_table_put(t); - return r; - } - - if (param->flags & DM_PERSISTENT_DEV_FLAG) - r = dm_create_with_minor(minor(to_kdev_t(param->dev)), t, &md); - else - r = dm_create(t, &md); - - if (r) { - dm_table_put(t); - return r; - } - dm_table_put(t); /* md will have grabbed its own reference */ - - set_disk_ro(dm_disk(md), (param->flags & DM_READONLY_FLAG) ? 1 : 0); - r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md); - dm_put(md); - - return r ? r : info(param, user); -} - -/* - * Build up the status struct for each target - */ -static int __status(struct mapped_device *md, struct dm_ioctl *param, - char *outbuf, size_t *len) -{ - unsigned int i, num_targets; - struct dm_target_spec *spec; - char *outptr; - status_type_t type; - struct dm_table *table = dm_get_table(md); - - if (param->flags & DM_STATUS_TABLE_FLAG) - type = STATUSTYPE_TABLE; - else - type = STATUSTYPE_INFO; - - outptr = outbuf; - - /* Get all the target info */ - num_targets = dm_table_get_num_targets(table); - for (i = 0; i < num_targets; i++) { - struct dm_target *ti = dm_table_get_target(table, i); - - if (outptr - outbuf + - sizeof(struct dm_target_spec) > param->data_size) { - dm_table_put(table); - return -ENOMEM; - } - - spec = (struct dm_target_spec *) outptr; - - spec->status = 0; - spec->sector_start = ti->begin; - spec->length = ti->len; - strlcpy(spec->target_type, ti->type->name, - sizeof(spec->target_type)); - - outptr += sizeof(struct dm_target_spec); - - /* Get the status/table string from the target driver */ - if (ti->type->status) - ti->type->status(ti, type, outptr, - outbuf + param->data_size - outptr); - else - outptr[0] = '\0'; - - outptr += strlen(outptr) + 1; - _align(outptr, ALIGNMENT); - spec->next = outptr - outbuf; - } - - param->target_count = num_targets; - *len = outptr - outbuf; - dm_table_put(table); - - return 0; -} - -/* - * Return the status of a device as a text string for each - * target. - */ -static int get_status(struct dm_ioctl *param, struct dm_ioctl *user) -{ - struct mapped_device *md; - size_t len = 0; - int ret; - char *outbuf = NULL; - - md = find_device(param); - if (!md) - /* - * Device not found - returns cleared exists flag. - */ - goto out; - - /* We haven't a clue how long the resultant data will be so - just allocate as much as userland has allowed us and make sure - we don't overun it */ - outbuf = kmalloc(param->data_size, GFP_KERNEL); - if (!outbuf) - goto out; - /* - * Get the status of all targets - */ - __status(md, param, outbuf, &len); - - /* - * Setup the basic dm_ioctl structure. - */ - __info(md, param); - - out: - if (md) - dm_put(md); - - ret = results_to_user(user, param, outbuf, len); - - if (outbuf) - kfree(outbuf); - - return ret; -} - -/* - * Wait for a device to report an event - */ -static int wait_device_event(struct dm_ioctl *param, struct dm_ioctl *user) -{ - struct mapped_device *md; - DECLARE_WAITQUEUE(wq, current); - - md = find_device(param); - if (!md) - /* - * Device not found - returns cleared exists flag. - */ - goto out; - - /* - * Setup the basic dm_ioctl structure. - */ - __info(md, param); - - /* - * Wait for a notification event - */ - set_current_state(TASK_INTERRUPTIBLE); - if (!dm_add_wait_queue(md, &wq, dm_get_event_nr(md))) { - yield(); - dm_remove_wait_queue(md, &wq); - } - set_current_state(TASK_RUNNING); - dm_put(md); - - out: - return results_to_user(user, param, NULL, 0); -} - -/* - * Retrieves a list of devices used by a particular dm device. - */ -static int dep(struct dm_ioctl *param, struct dm_ioctl *user) -{ - int r; - unsigned int count; - struct mapped_device *md; - struct list_head *tmp; - size_t len = 0; - struct dm_target_deps *deps = NULL; - struct dm_table *table; - - md = find_device(param); - if (!md) - goto out; - table = dm_get_table(md); - - /* - * Setup the basic dm_ioctl structure. - */ - __info(md, param); - - /* - * Count the devices. - */ - count = 0; - list_for_each(tmp, dm_table_get_devices(table)) - count++; - - /* - * Allocate a kernel space version of the dm_target_status - * struct. - */ - if (array_too_big(sizeof(*deps), sizeof(*deps->dev), count)) { - dm_table_put(table); - dm_put(md); - return -ENOMEM; - } - - len = sizeof(*deps) + (sizeof(*deps->dev) * count); - deps = kmalloc(len, GFP_KERNEL); - if (!deps) { - dm_table_put(table); - dm_put(md); - return -ENOMEM; - } - - /* - * Fill in the devices. - */ - deps->count = count; - count = 0; - list_for_each(tmp, dm_table_get_devices(table)) { - struct dm_dev *dd = list_entry(tmp, struct dm_dev, list); - deps->dev[count++] = dd->bdev->bd_dev; - } - dm_table_put(table); - dm_put(md); - - out: - r = results_to_user(user, param, deps, len); - - kfree(deps); - return r; -} - -static int remove(struct dm_ioctl *param, struct dm_ioctl *user) -{ - struct hash_cell *hc; - - down_write(&_hash_lock); - hc = *param->uuid ? __get_uuid_cell(param->uuid) : - __get_name_cell(param->name); - if (!hc) { - DMWARN("device doesn't appear to be in the dev hash table."); - up_write(&_hash_lock); - return -EINVAL; - } - - /* - * You may ask the interface to drop its reference to an - * in use device. This is no different to unlinking a - * file that someone still has open. The device will not - * actually be destroyed until the last opener closes it. - * The name and uuid of the device (both are interface - * properties) will be available for reuse immediately. - * - * You don't want to drop a _suspended_ device from the - * interface, since that will leave you with no way of - * resuming it. - */ - if (dm_suspended(hc->md)) { - DMWARN("refusing to remove a suspended device."); - up_write(&_hash_lock); - return -EPERM; - } - - __hash_remove(hc); - up_write(&_hash_lock); - return 0; -} - -static int remove_all(struct dm_ioctl *param, struct dm_ioctl *user) -{ - dm_hash_remove_all(); - return 0; -} - -static int suspend(struct dm_ioctl *param, struct dm_ioctl *user) -{ - int r; - struct mapped_device *md; - - md = find_device(param); - if (!md) - return -ENXIO; - - if (param->flags & DM_SUSPEND_FLAG) - r = dm_suspend(md); - else - r = dm_resume(md); - - dm_put(md); - return r; -} - -static int reload(struct dm_ioctl *param, struct dm_ioctl *user) -{ - int r; - struct mapped_device *md; - struct dm_table *t; - - r = dm_table_create(&t, get_mode(param)); - if (r) - return r; - - r = populate_table(t, param); - if (r) { - dm_table_put(t); - return r; - } - - md = find_device(param); - if (!md) { - dm_table_put(t); - return -ENXIO; - } - - r = dm_swap_table(md, t); - if (r) { - dm_put(md); - dm_table_put(t); - return r; - } - dm_table_put(t); /* md will have taken its own reference */ - - set_disk_ro(dm_disk(md), (param->flags & DM_READONLY_FLAG) ? 1 : 0); - dm_put(md); - - r = info(param, user); - return r; -} - -static int rename(struct dm_ioctl *param, struct dm_ioctl *user) -{ - int r; - char *new_name = (char *) param + param->data_start; - - if (valid_str(new_name, (void *) param, - (void *) param + param->data_size)) { - DMWARN("Invalid new logical volume name supplied."); - return -EINVAL; - } - - r = check_name(new_name); - if (r) - return r; - - return dm_hash_rename(param->name, new_name); -} - - -/*----------------------------------------------------------------- - * Implementation of open/close/ioctl on the special char - * device. - *---------------------------------------------------------------*/ -static ioctl_fn lookup_ioctl(unsigned int cmd) -{ - static struct { - int cmd; - ioctl_fn fn; - } _ioctls[] = { - {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */ - {DM_REMOVE_ALL_CMD, remove_all}, - {DM_DEV_CREATE_CMD, create}, - {DM_DEV_REMOVE_CMD, remove}, - {DM_DEV_RELOAD_CMD, reload}, - {DM_DEV_RENAME_CMD, rename}, - {DM_DEV_SUSPEND_CMD, suspend}, - {DM_DEV_DEPS_CMD, dep}, - {DM_DEV_STATUS_CMD, info}, - {DM_TARGET_STATUS_CMD, get_status}, - {DM_TARGET_WAIT_CMD, wait_device_event}, - }; - - return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn; -} - -/* - * As well as checking the version compatibility this always - * copies the kernel interface version out. - */ -static int check_version(unsigned int cmd, struct dm_ioctl *user) -{ - uint32_t version[3]; - int r = 0; - - if (copy_from_user(version, user->version, sizeof(version))) - return -EFAULT; - - if ((DM_VERSION_MAJOR != version[0]) || - (DM_VERSION_MINOR < version[1])) { - DMWARN("ioctl interface mismatch: " - "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)", - DM_VERSION_MAJOR, DM_VERSION_MINOR, - DM_VERSION_PATCHLEVEL, - version[0], version[1], version[2], cmd); - r = -EINVAL; - } - - /* - * Fill in the kernel version. - */ - version[0] = DM_VERSION_MAJOR; - version[1] = DM_VERSION_MINOR; - version[2] = DM_VERSION_PATCHLEVEL; - if (copy_to_user(user->version, version, sizeof(version))) - return -EFAULT; - - return r; -} - -static void free_params(struct dm_ioctl *param) -{ - vfree(param); -} - -static int copy_params(struct dm_ioctl *user, struct dm_ioctl **param) -{ - struct dm_ioctl tmp, *dmi; - - if (copy_from_user(&tmp, user, sizeof(tmp))) - return -EFAULT; - - if (tmp.data_size < sizeof(tmp)) - return -EINVAL; - - dmi = (struct dm_ioctl *) vmalloc(tmp.data_size); - if (!dmi) - return -ENOMEM; - - if (copy_from_user(dmi, user, tmp.data_size)) { - vfree(dmi); - return -EFAULT; - } - - *param = dmi; - return 0; -} - -static int validate_params(uint cmd, struct dm_ioctl *param) -{ - /* Ignores parameters */ - if (cmd == DM_REMOVE_ALL_CMD) - return 0; - - /* Unless creating, either name of uuid but not both */ - if (cmd != DM_DEV_CREATE_CMD) { - if ((!*param->uuid && !*param->name) || - (*param->uuid && *param->name)) { - DMWARN("one of name or uuid must be supplied"); - return -EINVAL; - } - } - - /* Ensure strings are terminated */ - param->name[DM_NAME_LEN - 1] = '\0'; - param->uuid[DM_UUID_LEN - 1] = '\0'; - - return 0; -} - -static int ctl_ioctl(struct inode *inode, struct file *file, - uint command, ulong u) -{ - int r = 0; - unsigned int cmd; - struct dm_ioctl *param; - struct dm_ioctl *user = (struct dm_ioctl *) u; - ioctl_fn fn = NULL; - - /* only root can play with this */ - if (!capable(CAP_SYS_ADMIN)) - return -EACCES; - - if (_IOC_TYPE(command) != DM_IOCTL) - return -ENOTTY; - - cmd = _IOC_NR(command); - - /* - * Check the interface version passed in. This also - * writes out the kernels interface version. - */ - r = check_version(cmd, user); - if (r) - return r; - - /* - * Nothing more to do for the version command. - */ - if (cmd == DM_VERSION_CMD) - return 0; - - fn = lookup_ioctl(cmd); - if (!fn) { - DMWARN("dm_ctl_ioctl: unknown command 0x%x", command); - return -ENOTTY; - } - - /* - * Copy the parameters into kernel space. - */ - r = copy_params(user, ¶m); - if (r) - return r; - - r = validate_params(cmd, param); - if (r) { - free_params(param); - return r; - } - - r = fn(param, user); - free_params(param); - return r; -} - -static struct file_operations _ctl_fops = { - .ioctl = ctl_ioctl, - .owner = THIS_MODULE, -}; - -static struct miscdevice _dm_misc = { - .minor = MISC_DYNAMIC_MINOR, - .name = DM_NAME, - .devfs_name = "mapper/control", - .fops = &_ctl_fops -}; - -/* - * Create misc character device and link to DM_DIR/control. - */ -int __init dm_interface_init(void) -{ - int r; - - r = dm_hash_init(); - if (r) - return r; - - r = misc_register(&_dm_misc); - if (r) { - DMERR("misc_register failed for control device"); - dm_hash_exit(); - return r; - } - - DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR, - DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA, - DM_DRIVER_EMAIL); - return 0; - - if (misc_deregister(&_dm_misc) < 0) - DMERR("misc_deregister failed for control device"); - dm_hash_exit(); - return r; -} -void dm_interface_exit(void) -{ - if (misc_deregister(&_dm_misc) < 0) - DMERR("misc_deregister failed for control device"); - dm_hash_exit(); -} +#ifdef CONFIG_DM_IOCTL_V4 +#include "dm-ioctl-v4.c" +#else +#include "dm-ioctl-v1.c" +#endif --- diff/drivers/md/dm.c 2003-06-30 17:12:16.000000000 +0100 +++ source/drivers/md/dm.c 2003-07-01 15:36:42.000000000 +0100 @@ -516,6 +516,11 @@ down_read(&md->lock); } + if (!md->map) { + bio_io_error(bio, bio->bi_size); + return 0; + } + __split_bio(md, bio); up_read(&md->lock); return 0; @@ -672,6 +677,9 @@ static void __unbind(struct mapped_device *md) { + if (!md->map) + return; + dm_table_event_callback(md->map, NULL, NULL); dm_table_put(md->map); md->map = NULL; @@ -682,35 +690,26 @@ * Constructor for a new device. */ static int create_aux(unsigned int minor, int persistent, - struct dm_table *table, struct mapped_device **result) + struct mapped_device **result) { - int r; struct mapped_device *md; md = alloc_dev(minor, persistent); if (!md) return -ENXIO; - r = __bind(md, table); - if (r) { - free_dev(md); - return r; - } - dm_table_resume_targets(md->map); - *result = md; return 0; } -int dm_create(struct dm_table *table, struct mapped_device **result) +int dm_create(struct mapped_device **result) { - return create_aux(0, 0, table, result); + return create_aux(0, 0, result); } -int dm_create_with_minor(unsigned int minor, - struct dm_table *table, struct mapped_device **result) +int dm_create_with_minor(unsigned int minor, struct mapped_device **result) { - return create_aux(minor, 1, table, result); + return create_aux(minor, 1, result); } void dm_get(struct mapped_device *md) @@ -721,7 +720,7 @@ void dm_put(struct mapped_device *md) { if (atomic_dec_and_test(&md->holders)) { - if (!test_bit(DMF_SUSPENDED, &md->flags)) + if (!test_bit(DMF_SUSPENDED, &md->flags) && md->map) dm_table_suspend_targets(md->map); __unbind(md); free_dev(md); @@ -812,7 +811,8 @@ down_write(&md->lock); remove_wait_queue(&md->wait, &wait); set_bit(DMF_SUSPENDED, &md->flags); - dm_table_suspend_targets(md->map); + if (md->map) + dm_table_suspend_targets(md->map); up_write(&md->lock); return 0; @@ -823,7 +823,8 @@ struct deferred_io *def; down_write(&md->lock); - if (!test_bit(DMF_SUSPENDED, &md->flags) || + if (!md->map || + !test_bit(DMF_SUSPENDED, &md->flags) || !dm_table_get_size(md->map)) { up_write(&md->lock); return -EINVAL; @@ -893,7 +894,8 @@ down_read(&md->lock); t = md->map; - dm_table_get(t); + if (t) + dm_table_get(t); up_read(&md->lock); return t; --- diff/drivers/md/dm.h 2003-06-30 17:11:07.000000000 +0100 +++ source/drivers/md/dm.h 2003-07-01 15:36:42.000000000 +0100 @@ -51,9 +51,8 @@ * Functions for manipulating a struct mapped_device. * Drop the reference with dm_put when you finish with the object. *---------------------------------------------------------------*/ -int dm_create(struct dm_table *table, struct mapped_device **md); -int dm_create_with_minor(unsigned int minor, struct dm_table *table, - struct mapped_device **md); +int dm_create(struct mapped_device **md); +int dm_create_with_minor(unsigned int minor, struct mapped_device **md); /* * Reference counting for md. --- diff/include/linux/dm-ioctl.h 2002-12-30 10:17:13.000000000 +0000 +++ source/include/linux/dm-ioctl.h 2003-07-01 15:36:42.000000000 +0100 @@ -1,5 +1,5 @@ /* - * Copyright (C) 2001 Sistina Software (UK) Limited. + * Copyright (C) 2003 Sistina Software (UK) Limited. * * This file is released under the LGPL. */ @@ -7,143 +7,12 @@ #ifndef _LINUX_DM_IOCTL_H #define _LINUX_DM_IOCTL_H -#include +#include -#define DM_DIR "mapper" /* Slashes not supported */ -#define DM_MAX_TYPE_NAME 16 -#define DM_NAME_LEN 128 -#define DM_UUID_LEN 129 +#ifdef CONFIG_DM_IOCTL_V4 +#include "dm-ioctl-v4.h" +#else +#include "dm-ioctl-v1.h" +#endif -/* - * Implements a traditional ioctl interface to the device mapper. - */ - -/* - * All ioctl arguments consist of a single chunk of memory, with - * this structure at the start. If a uuid is specified any - * lookup (eg. for a DM_INFO) will be done on that, *not* the - * name. - */ -struct dm_ioctl { - /* - * The version number is made up of three parts: - * major - no backward or forward compatibility, - * minor - only backwards compatible, - * patch - both backwards and forwards compatible. - * - * All clients of the ioctl interface should fill in the - * version number of the interface that they were - * compiled with. - * - * All recognised ioctl commands (ie. those that don't - * return -ENOTTY) fill out this field, even if the - * command failed. - */ - uint32_t version[3]; /* in/out */ - uint32_t data_size; /* total size of data passed in - * including this struct */ - - uint32_t data_start; /* offset to start of data - * relative to start of this struct */ - - uint32_t target_count; /* in/out */ - uint32_t open_count; /* out */ - uint32_t flags; /* in/out */ - - __kernel_dev_t dev; /* in/out */ - - char name[DM_NAME_LEN]; /* device name */ - char uuid[DM_UUID_LEN]; /* unique identifier for - * the block device */ -}; - -/* - * Used to specify tables. These structures appear after the - * dm_ioctl. - */ -struct dm_target_spec { - int32_t status; /* used when reading from kernel only */ - uint64_t sector_start; - uint32_t length; - - /* - * Offset in bytes (from the start of this struct) to - * next target_spec. - */ - uint32_t next; - - char target_type[DM_MAX_TYPE_NAME]; - - /* - * Parameter string starts immediately after this object. - * Be careful to add padding after string to ensure correct - * alignment of subsequent dm_target_spec. - */ -}; - -/* - * Used to retrieve the target dependencies. - */ -struct dm_target_deps { - uint32_t count; - - __kernel_dev_t dev[0]; /* out */ -}; - -/* - * If you change this make sure you make the corresponding change - * to dm-ioctl.c:lookup_ioctl() - */ -enum { - /* Top level cmds */ - DM_VERSION_CMD = 0, - DM_REMOVE_ALL_CMD, - - /* device level cmds */ - DM_DEV_CREATE_CMD, - DM_DEV_REMOVE_CMD, - DM_DEV_RELOAD_CMD, - DM_DEV_RENAME_CMD, - DM_DEV_SUSPEND_CMD, - DM_DEV_DEPS_CMD, - DM_DEV_STATUS_CMD, - - /* target level cmds */ - DM_TARGET_STATUS_CMD, - DM_TARGET_WAIT_CMD -}; - -#define DM_IOCTL 0xfd - -#define DM_VERSION _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl) -#define DM_REMOVE_ALL _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl) - -#define DM_DEV_CREATE _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, struct dm_ioctl) -#define DM_DEV_REMOVE _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, struct dm_ioctl) -#define DM_DEV_RELOAD _IOWR(DM_IOCTL, DM_DEV_RELOAD_CMD, struct dm_ioctl) -#define DM_DEV_SUSPEND _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl) -#define DM_DEV_RENAME _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, struct dm_ioctl) -#define DM_DEV_DEPS _IOWR(DM_IOCTL, DM_DEV_DEPS_CMD, struct dm_ioctl) -#define DM_DEV_STATUS _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl) - -#define DM_TARGET_STATUS _IOWR(DM_IOCTL, DM_TARGET_STATUS_CMD, struct dm_ioctl) -#define DM_TARGET_WAIT _IOWR(DM_IOCTL, DM_TARGET_WAIT_CMD, struct dm_ioctl) - -#define DM_VERSION_MAJOR 1 -#define DM_VERSION_MINOR 0 -#define DM_VERSION_PATCHLEVEL 6 -#define DM_VERSION_EXTRA "-ioctl (2002-10-15)" - -/* Status bits */ -#define DM_READONLY_FLAG 0x00000001 -#define DM_SUSPEND_FLAG 0x00000002 -#define DM_EXISTS_FLAG 0x00000004 -#define DM_PERSISTENT_DEV_FLAG 0x00000008 - -/* - * Flag passed into ioctl STATUS command to get table information - * rather than current status. - */ -#define DM_STATUS_TABLE_FLAG 0x00000010 - -#endif /* _LINUX_DM_IOCTL_H */ +#endif --- diff/drivers/md/dm-ioctl-v1.c 1970-01-01 01:00:00.000000000 +0100 +++ source/drivers/md/dm-ioctl-v1.c 2003-07-01 15:36:42.000000000 +0100 @@ -0,0 +1,1160 @@ +/* + * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. + * + * This file is released under the GPL. + */ + +#include "dm.h" + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define DM_DRIVER_EMAIL "dm@uk.sistina.com" + +/*----------------------------------------------------------------- + * The ioctl interface needs to be able to look up devices by + * name or uuid. + *---------------------------------------------------------------*/ +struct hash_cell { + struct list_head name_list; + struct list_head uuid_list; + + char *name; + char *uuid; + struct mapped_device *md; +}; + +#define NUM_BUCKETS 64 +#define MASK_BUCKETS (NUM_BUCKETS - 1) +static struct list_head _name_buckets[NUM_BUCKETS]; +static struct list_head _uuid_buckets[NUM_BUCKETS]; + +void dm_hash_remove_all(void); + +/* + * Guards access to all three tables. + */ +static DECLARE_RWSEM(_hash_lock); + +static void init_buckets(struct list_head *buckets) +{ + unsigned int i; + + for (i = 0; i < NUM_BUCKETS; i++) + INIT_LIST_HEAD(buckets + i); +} + +int dm_hash_init(void) +{ + init_buckets(_name_buckets); + init_buckets(_uuid_buckets); + devfs_mk_dir(DM_DIR); + return 0; +} + +void dm_hash_exit(void) +{ + dm_hash_remove_all(); + devfs_remove(DM_DIR); +} + +/*----------------------------------------------------------------- + * Hash function: + * We're not really concerned with the str hash function being + * fast since it's only used by the ioctl interface. + *---------------------------------------------------------------*/ +static unsigned int hash_str(const char *str) +{ + const unsigned int hash_mult = 2654435387U; + unsigned int h = 0; + + while (*str) + h = (h + (unsigned int) *str++) * hash_mult; + + return h & MASK_BUCKETS; +} + +/*----------------------------------------------------------------- + * Code for looking up a device by name + *---------------------------------------------------------------*/ +static struct hash_cell *__get_name_cell(const char *str) +{ + struct list_head *tmp; + struct hash_cell *hc; + unsigned int h = hash_str(str); + + list_for_each (tmp, _name_buckets + h) { + hc = list_entry(tmp, struct hash_cell, name_list); + if (!strcmp(hc->name, str)) + return hc; + } + + return NULL; +} + +static struct hash_cell *__get_uuid_cell(const char *str) +{ + struct list_head *tmp; + struct hash_cell *hc; + unsigned int h = hash_str(str); + + list_for_each (tmp, _uuid_buckets + h) { + hc = list_entry(tmp, struct hash_cell, uuid_list); + if (!strcmp(hc->uuid, str)) + return hc; + } + + return NULL; +} + +/*----------------------------------------------------------------- + * Inserting, removing and renaming a device. + *---------------------------------------------------------------*/ +static inline char *kstrdup(const char *str) +{ + char *r = kmalloc(strlen(str) + 1, GFP_KERNEL); + if (r) + strcpy(r, str); + return r; +} + +static struct hash_cell *alloc_cell(const char *name, const char *uuid, + struct mapped_device *md) +{ + struct hash_cell *hc; + + hc = kmalloc(sizeof(*hc), GFP_KERNEL); + if (!hc) + return NULL; + + hc->name = kstrdup(name); + if (!hc->name) { + kfree(hc); + return NULL; + } + + if (!uuid) + hc->uuid = NULL; + + else { + hc->uuid = kstrdup(uuid); + if (!hc->uuid) { + kfree(hc->name); + kfree(hc); + return NULL; + } + } + + INIT_LIST_HEAD(&hc->name_list); + INIT_LIST_HEAD(&hc->uuid_list); + hc->md = md; + return hc; +} + +static void free_cell(struct hash_cell *hc) +{ + if (hc) { + kfree(hc->name); + kfree(hc->uuid); + kfree(hc); + } +} + +/* + * devfs stuff. + */ +static int register_with_devfs(struct hash_cell *hc) +{ + struct gendisk *disk = dm_disk(hc->md); + + devfs_mk_bdev(MKDEV(disk->major, disk->first_minor), + S_IFBLK | S_IRUSR | S_IWUSR | S_IRGRP, + DM_DIR "/%s", hc->name); + return 0; +} + +static int unregister_with_devfs(struct hash_cell *hc) +{ + devfs_remove(DM_DIR"/%s", hc->name); + return 0; +} + +/* + * The kdev_t and uuid of a device can never change once it is + * initially inserted. + */ +int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md) +{ + struct hash_cell *cell; + + /* + * Allocate the new cells. + */ + cell = alloc_cell(name, uuid, md); + if (!cell) + return -ENOMEM; + + /* + * Insert the cell into all three hash tables. + */ + down_write(&_hash_lock); + if (__get_name_cell(name)) + goto bad; + + list_add(&cell->name_list, _name_buckets + hash_str(name)); + + if (uuid) { + if (__get_uuid_cell(uuid)) { + list_del(&cell->name_list); + goto bad; + } + list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid)); + } + register_with_devfs(cell); + dm_get(md); + up_write(&_hash_lock); + + return 0; + + bad: + up_write(&_hash_lock); + free_cell(cell); + return -EBUSY; +} + +void __hash_remove(struct hash_cell *hc) +{ + /* remove from the dev hash */ + list_del(&hc->uuid_list); + list_del(&hc->name_list); + unregister_with_devfs(hc); + dm_put(hc->md); + free_cell(hc); +} + +void dm_hash_remove_all(void) +{ + int i; + struct hash_cell *hc; + struct list_head *tmp, *n; + + down_write(&_hash_lock); + for (i = 0; i < NUM_BUCKETS; i++) { + list_for_each_safe (tmp, n, _name_buckets + i) { + hc = list_entry(tmp, struct hash_cell, name_list); + __hash_remove(hc); + } + } + up_write(&_hash_lock); +} + +int dm_hash_rename(const char *old, const char *new) +{ + char *new_name, *old_name; + struct hash_cell *hc; + + /* + * duplicate new. + */ + new_name = kstrdup(new); + if (!new_name) + return -ENOMEM; + + down_write(&_hash_lock); + + /* + * Is new free ? + */ + hc = __get_name_cell(new); + if (hc) { + DMWARN("asked to rename to an already existing name %s -> %s", + old, new); + up_write(&_hash_lock); + kfree(new_name); + return -EBUSY; + } + + /* + * Is there such a device as 'old' ? + */ + hc = __get_name_cell(old); + if (!hc) { + DMWARN("asked to rename a non existent device %s -> %s", + old, new); + up_write(&_hash_lock); + kfree(new_name); + return -ENXIO; + } + + /* + * rename and move the name cell. + */ + unregister_with_devfs(hc); + + list_del(&hc->name_list); + old_name = hc->name; + hc->name = new_name; + list_add(&hc->name_list, _name_buckets + hash_str(new_name)); + + /* rename the device node in devfs */ + register_with_devfs(hc); + + up_write(&_hash_lock); + kfree(old_name); + return 0; +} + + +/*----------------------------------------------------------------- + * Implementation of the ioctl commands + *---------------------------------------------------------------*/ + +/* + * All the ioctl commands get dispatched to functions with this + * prototype. + */ +typedef int (*ioctl_fn)(struct dm_ioctl *param, struct dm_ioctl *user); + +/* + * Check a string doesn't overrun the chunk of + * memory we copied from userland. + */ +static int valid_str(char *str, void *begin, void *end) +{ + while (((void *) str >= begin) && ((void *) str < end)) + if (!*str++) + return 0; + + return -EINVAL; +} + +static int next_target(struct dm_target_spec *last, uint32_t next, + void *begin, void *end, + struct dm_target_spec **spec, char **params) +{ + *spec = (struct dm_target_spec *) + ((unsigned char *) last + next); + *params = (char *) (*spec + 1); + + if (*spec < (last + 1) || ((void *) *spec > end)) + return -EINVAL; + + return valid_str(*params, begin, end); +} + +static int populate_table(struct dm_table *table, struct dm_ioctl *args) +{ + int r, first = 1; + unsigned int i = 0; + struct dm_target_spec *spec; + char *params; + void *begin, *end; + + if (!args->target_count) { + DMWARN("populate_table: no targets specified"); + return -EINVAL; + } + + begin = (void *) args; + end = begin + args->data_size; + + for (i = 0; i < args->target_count; i++) { + + if (first) + r = next_target((struct dm_target_spec *) args, + args->data_start, + begin, end, &spec, ¶ms); + else + r = next_target(spec, spec->next, begin, end, + &spec, ¶ms); + + if (r) { + DMWARN("unable to find target"); + return -EINVAL; + } + + r = dm_table_add_target(table, spec->target_type, + (sector_t) spec->sector_start, + (sector_t) spec->length, + params); + if (r) { + DMWARN("internal error adding target to table"); + return -EINVAL; + } + + first = 0; + } + + return dm_table_complete(table); +} + +/* + * Round up the ptr to the next 'align' boundary. Obviously + * 'align' must be a power of 2. + */ +static inline void *align_ptr(void *ptr, unsigned int align) +{ + align--; + return (void *) (((unsigned long) (ptr + align)) & ~align); +} + +/* + * Copies a dm_ioctl and an optional additional payload to + * userland. + */ +static int results_to_user(struct dm_ioctl *user, struct dm_ioctl *param, + void *data, uint32_t len) +{ + int r; + void *ptr = NULL; + + if (data) { + ptr = align_ptr(user + 1, sizeof(unsigned long)); + param->data_start = ptr - (void *) user; + } + + /* + * The version number has already been filled in, so we + * just copy later fields. + */ + r = copy_to_user(&user->data_size, ¶m->data_size, + sizeof(*param) - sizeof(param->version)); + if (r) + return -EFAULT; + + if (data) { + if (param->data_start + len > param->data_size) + return -ENOSPC; + + if (copy_to_user(ptr, data, len)) + r = -EFAULT; + } + + return r; +} + +/* + * Fills in a dm_ioctl structure, ready for sending back to + * userland. + */ +static int __info(struct mapped_device *md, struct dm_ioctl *param) +{ + struct dm_table *table; + struct block_device *bdev; + struct gendisk *disk = dm_disk(md); + + param->flags = DM_EXISTS_FLAG; + if (dm_suspended(md)) + param->flags |= DM_SUSPEND_FLAG; + + bdev = bdget_disk(disk, 0); + if (!bdev) + return -ENXIO; + + param->dev = bdev->bd_dev; + param->open_count = bdev->bd_openers; + bdput(bdev); + + if (disk->policy) + param->flags |= DM_READONLY_FLAG; + + table = dm_get_table(md); + param->target_count = dm_table_get_num_targets(table); + dm_table_put(table); + + return 0; +} + +/* + * Always use UUID for lookups if it's present, otherwise use name. + */ +static inline struct mapped_device *find_device(struct dm_ioctl *param) +{ + struct hash_cell *hc; + struct mapped_device *md = NULL; + + down_read(&_hash_lock); + hc = *param->uuid ? __get_uuid_cell(param->uuid) : + __get_name_cell(param->name); + 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'; + + dm_get(md); + } + up_read(&_hash_lock); + + return md; +} + +#define ALIGNMENT sizeof(int) +static void *_align(void *ptr, unsigned int a) +{ + register unsigned long align = --a; + + return (void *) (((unsigned long) ptr + align) & ~align); +} + +/* + * Copies device info back to user space, used by + * the create and info ioctls. + */ +static int info(struct dm_ioctl *param, struct dm_ioctl *user) +{ + struct mapped_device *md; + + param->flags = 0; + + md = find_device(param); + if (!md) + /* + * Device not found - returns cleared exists flag. + */ + goto out; + + __info(md, param); + dm_put(md); + + out: + return results_to_user(user, param, NULL, 0); +} + +static inline int get_mode(struct dm_ioctl *param) +{ + int mode = FMODE_READ | FMODE_WRITE; + + if (param->flags & DM_READONLY_FLAG) + mode = FMODE_READ; + + return mode; +} + +static int check_name(const char *name) +{ + if (name[0] == '/') { + DMWARN("invalid device name"); + return -EINVAL; + } + + return 0; +} + +static int create(struct dm_ioctl *param, struct dm_ioctl *user) +{ + int r; + struct dm_table *t; + struct mapped_device *md; + + r = check_name(param->name); + if (r) + return r; + + r = dm_table_create(&t, get_mode(param)); + if (r) + return r; + + r = populate_table(t, param); + if (r) { + dm_table_put(t); + return r; + } + + if (param->flags & DM_PERSISTENT_DEV_FLAG) + r = dm_create_with_minor(minor(to_kdev_t(param->dev)), &md); + else + r = dm_create(&md); + + if (r) { + dm_table_put(t); + return r; + } + + /* suspend the device */ + r = dm_suspend(md); + if (r) { + DMWARN("suspend failed"); + dm_table_put(t); + dm_put(md); + return r; + } + /* swap in the table */ + r = dm_swap_table(md, t); + if (r) { + DMWARN("table swap failed"); + dm_table_put(t); + dm_put(md); + return r; + } + + /* resume the device */ + r = dm_resume(md); + if (r) { + DMWARN("resume failed"); + dm_table_put(t); + dm_put(md); + return r; + } + + dm_table_put(t); /* md will have grabbed its own reference */ + + set_disk_ro(dm_disk(md), (param->flags & DM_READONLY_FLAG) ? 1 : 0); + r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md); + dm_put(md); + + return r ? r : info(param, user); +} + +/* + * Build up the status struct for each target + */ +static int __status(struct mapped_device *md, struct dm_ioctl *param, + char *outbuf, size_t *len) +{ + unsigned int i, num_targets; + struct dm_target_spec *spec; + char *outptr; + status_type_t type; + struct dm_table *table = dm_get_table(md); + + if (param->flags & DM_STATUS_TABLE_FLAG) + type = STATUSTYPE_TABLE; + else + type = STATUSTYPE_INFO; + + outptr = outbuf; + + /* Get all the target info */ + num_targets = dm_table_get_num_targets(table); + for (i = 0; i < num_targets; i++) { + struct dm_target *ti = dm_table_get_target(table, i); + + if (outptr - outbuf + + sizeof(struct dm_target_spec) > param->data_size) { + dm_table_put(table); + return -ENOMEM; + } + + spec = (struct dm_target_spec *) outptr; + + spec->status = 0; + spec->sector_start = ti->begin; + spec->length = ti->len; + strlcpy(spec->target_type, ti->type->name, + sizeof(spec->target_type)); + + outptr += sizeof(struct dm_target_spec); + + /* Get the status/table string from the target driver */ + if (ti->type->status) + ti->type->status(ti, type, outptr, + outbuf + param->data_size - outptr); + else + outptr[0] = '\0'; + + outptr += strlen(outptr) + 1; + _align(outptr, ALIGNMENT); + spec->next = outptr - outbuf; + } + + param->target_count = num_targets; + *len = outptr - outbuf; + dm_table_put(table); + + return 0; +} + +/* + * Return the status of a device as a text string for each + * target. + */ +static int get_status(struct dm_ioctl *param, struct dm_ioctl *user) +{ + struct mapped_device *md; + size_t len = 0; + int ret; + char *outbuf = NULL; + + md = find_device(param); + if (!md) + /* + * Device not found - returns cleared exists flag. + */ + goto out; + + /* We haven't a clue how long the resultant data will be so + just allocate as much as userland has allowed us and make sure + we don't overun it */ + outbuf = kmalloc(param->data_size, GFP_KERNEL); + if (!outbuf) + goto out; + /* + * Get the status of all targets + */ + __status(md, param, outbuf, &len); + + /* + * Setup the basic dm_ioctl structure. + */ + __info(md, param); + + out: + if (md) + dm_put(md); + + ret = results_to_user(user, param, outbuf, len); + + if (outbuf) + kfree(outbuf); + + return ret; +} + +/* + * Wait for a device to report an event + */ +static int wait_device_event(struct dm_ioctl *param, struct dm_ioctl *user) +{ + struct mapped_device *md; + DECLARE_WAITQUEUE(wq, current); + + md = find_device(param); + if (!md) + /* + * Device not found - returns cleared exists flag. + */ + goto out; + + /* + * Setup the basic dm_ioctl structure. + */ + __info(md, param); + + /* + * Wait for a notification event + */ + set_current_state(TASK_INTERRUPTIBLE); + if (!dm_add_wait_queue(md, &wq, dm_get_event_nr(md))) { + yield(); + dm_remove_wait_queue(md, &wq); + } + set_current_state(TASK_RUNNING); + dm_put(md); + + out: + return results_to_user(user, param, NULL, 0); +} + +/* + * Retrieves a list of devices used by a particular dm device. + */ +static int dep(struct dm_ioctl *param, struct dm_ioctl *user) +{ + int r; + unsigned int count; + struct mapped_device *md; + struct list_head *tmp; + size_t len = 0; + struct dm_target_deps *deps = NULL; + struct dm_table *table; + + md = find_device(param); + if (!md) + goto out; + table = dm_get_table(md); + + /* + * Setup the basic dm_ioctl structure. + */ + __info(md, param); + + /* + * Count the devices. + */ + count = 0; + list_for_each(tmp, dm_table_get_devices(table)) + count++; + + /* + * Allocate a kernel space version of the dm_target_status + * struct. + */ + if (array_too_big(sizeof(*deps), sizeof(*deps->dev), count)) { + dm_table_put(table); + dm_put(md); + return -ENOMEM; + } + + len = sizeof(*deps) + (sizeof(*deps->dev) * count); + deps = kmalloc(len, GFP_KERNEL); + if (!deps) { + dm_table_put(table); + dm_put(md); + return -ENOMEM; + } + + /* + * Fill in the devices. + */ + deps->count = count; + count = 0; + list_for_each(tmp, dm_table_get_devices(table)) { + struct dm_dev *dd = list_entry(tmp, struct dm_dev, list); + deps->dev[count++] = dd->bdev->bd_dev; + } + dm_table_put(table); + dm_put(md); + + out: + r = results_to_user(user, param, deps, len); + + kfree(deps); + return r; +} + +static int remove(struct dm_ioctl *param, struct dm_ioctl *user) +{ + struct hash_cell *hc; + + down_write(&_hash_lock); + hc = *param->uuid ? __get_uuid_cell(param->uuid) : + __get_name_cell(param->name); + if (!hc) { + DMWARN("device doesn't appear to be in the dev hash table."); + up_write(&_hash_lock); + return -EINVAL; + } + + /* + * You may ask the interface to drop its reference to an + * in use device. This is no different to unlinking a + * file that someone still has open. The device will not + * actually be destroyed until the last opener closes it. + * The name and uuid of the device (both are interface + * properties) will be available for reuse immediately. + * + * You don't want to drop a _suspended_ device from the + * interface, since that will leave you with no way of + * resuming it. + */ + if (dm_suspended(hc->md)) { + DMWARN("refusing to remove a suspended device."); + up_write(&_hash_lock); + return -EPERM; + } + + __hash_remove(hc); + up_write(&_hash_lock); + return 0; +} + +static int remove_all(struct dm_ioctl *param, struct dm_ioctl *user) +{ + dm_hash_remove_all(); + return 0; +} + +static int suspend(struct dm_ioctl *param, struct dm_ioctl *user) +{ + int r; + struct mapped_device *md; + + md = find_device(param); + if (!md) + return -ENXIO; + + if (param->flags & DM_SUSPEND_FLAG) + r = dm_suspend(md); + else + r = dm_resume(md); + + dm_put(md); + return r; +} + +static int reload(struct dm_ioctl *param, struct dm_ioctl *user) +{ + int r; + struct mapped_device *md; + struct dm_table *t; + + r = dm_table_create(&t, get_mode(param)); + if (r) + return r; + + r = populate_table(t, param); + if (r) { + dm_table_put(t); + return r; + } + + md = find_device(param); + if (!md) { + dm_table_put(t); + return -ENXIO; + } + + r = dm_swap_table(md, t); + if (r) { + dm_put(md); + dm_table_put(t); + return r; + } + dm_table_put(t); /* md will have taken its own reference */ + + set_disk_ro(dm_disk(md), (param->flags & DM_READONLY_FLAG) ? 1 : 0); + dm_put(md); + + r = info(param, user); + return r; +} + +static int rename(struct dm_ioctl *param, struct dm_ioctl *user) +{ + int r; + char *new_name = (char *) param + param->data_start; + + if (valid_str(new_name, (void *) param, + (void *) param + param->data_size)) { + DMWARN("Invalid new logical volume name supplied."); + return -EINVAL; + } + + r = check_name(new_name); + if (r) + return r; + + return dm_hash_rename(param->name, new_name); +} + + +/*----------------------------------------------------------------- + * Implementation of open/close/ioctl on the special char + * device. + *---------------------------------------------------------------*/ +static ioctl_fn lookup_ioctl(unsigned int cmd) +{ + static struct { + int cmd; + ioctl_fn fn; + } _ioctls[] = { + {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */ + {DM_REMOVE_ALL_CMD, remove_all}, + {DM_DEV_CREATE_CMD, create}, + {DM_DEV_REMOVE_CMD, remove}, + {DM_DEV_RELOAD_CMD, reload}, + {DM_DEV_RENAME_CMD, rename}, + {DM_DEV_SUSPEND_CMD, suspend}, + {DM_DEV_DEPS_CMD, dep}, + {DM_DEV_STATUS_CMD, info}, + {DM_TARGET_STATUS_CMD, get_status}, + {DM_TARGET_WAIT_CMD, wait_device_event}, + }; + + return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn; +} + +/* + * As well as checking the version compatibility this always + * copies the kernel interface version out. + */ +static int check_version(unsigned int cmd, struct dm_ioctl *user) +{ + uint32_t version[3]; + int r = 0; + + if (copy_from_user(version, user->version, sizeof(version))) + return -EFAULT; + + if ((DM_VERSION_MAJOR != version[0]) || + (DM_VERSION_MINOR < version[1])) { + DMWARN("ioctl interface mismatch: " + "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)", + DM_VERSION_MAJOR, DM_VERSION_MINOR, + DM_VERSION_PATCHLEVEL, + version[0], version[1], version[2], cmd); + r = -EINVAL; + } + + /* + * Fill in the kernel version. + */ + version[0] = DM_VERSION_MAJOR; + version[1] = DM_VERSION_MINOR; + version[2] = DM_VERSION_PATCHLEVEL; + if (copy_to_user(user->version, version, sizeof(version))) + return -EFAULT; + + return r; +} + +static void free_params(struct dm_ioctl *param) +{ + vfree(param); +} + +static int copy_params(struct dm_ioctl *user, struct dm_ioctl **param) +{ + struct dm_ioctl tmp, *dmi; + + if (copy_from_user(&tmp, user, sizeof(tmp))) + return -EFAULT; + + if (tmp.data_size < sizeof(tmp)) + return -EINVAL; + + dmi = (struct dm_ioctl *) vmalloc(tmp.data_size); + if (!dmi) + return -ENOMEM; + + if (copy_from_user(dmi, user, tmp.data_size)) { + vfree(dmi); + return -EFAULT; + } + + *param = dmi; + return 0; +} + +static int validate_params(uint cmd, struct dm_ioctl *param) +{ + /* Ignores parameters */ + if (cmd == DM_REMOVE_ALL_CMD) + return 0; + + /* Unless creating, either name of uuid but not both */ + if (cmd != DM_DEV_CREATE_CMD) { + if ((!*param->uuid && !*param->name) || + (*param->uuid && *param->name)) { + DMWARN("one of name or uuid must be supplied"); + return -EINVAL; + } + } + + /* Ensure strings are terminated */ + param->name[DM_NAME_LEN - 1] = '\0'; + param->uuid[DM_UUID_LEN - 1] = '\0'; + + return 0; +} + +static int ctl_ioctl(struct inode *inode, struct file *file, + uint command, ulong u) +{ + int r = 0; + unsigned int cmd; + struct dm_ioctl *param; + struct dm_ioctl *user = (struct dm_ioctl *) u; + ioctl_fn fn = NULL; + + /* only root can play with this */ + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + if (_IOC_TYPE(command) != DM_IOCTL) + return -ENOTTY; + + cmd = _IOC_NR(command); + + /* + * Check the interface version passed in. This also + * writes out the kernels interface version. + */ + r = check_version(cmd, user); + if (r) + return r; + + /* + * Nothing more to do for the version command. + */ + if (cmd == DM_VERSION_CMD) + return 0; + + fn = lookup_ioctl(cmd); + if (!fn) { + DMWARN("dm_ctl_ioctl: unknown command 0x%x", command); + return -ENOTTY; + } + + /* + * Copy the parameters into kernel space. + */ + r = copy_params(user, ¶m); + if (r) + return r; + + r = validate_params(cmd, param); + if (r) { + free_params(param); + return r; + } + + r = fn(param, user); + free_params(param); + return r; +} + +static struct file_operations _ctl_fops = { + .ioctl = ctl_ioctl, + .owner = THIS_MODULE, +}; + +static struct miscdevice _dm_misc = { + .minor = MISC_DYNAMIC_MINOR, + .name = DM_NAME, + .devfs_name = "mapper/control", + .fops = &_ctl_fops +}; + +/* + * Create misc character device and link to DM_DIR/control. + */ +int __init dm_interface_init(void) +{ + int r; + + r = dm_hash_init(); + if (r) + return r; + + r = misc_register(&_dm_misc); + if (r) { + DMERR("misc_register failed for control device"); + dm_hash_exit(); + return r; + } + + DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR, + DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA, + DM_DRIVER_EMAIL); + return 0; + + if (misc_deregister(&_dm_misc) < 0) + DMERR("misc_deregister failed for control device"); + dm_hash_exit(); + return r; +} + +void dm_interface_exit(void) +{ + if (misc_deregister(&_dm_misc) < 0) + DMERR("misc_deregister failed for control device"); + dm_hash_exit(); +} --- diff/drivers/md/dm-ioctl-v4.c 1970-01-01 01:00:00.000000000 +0100 +++ source/drivers/md/dm-ioctl-v4.c 2003-07-01 15:36:42.000000000 +0100 @@ -0,0 +1,1248 @@ +/* + * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. + * + * This file is released under the GPL. + */ + +#include "dm.h" + +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define DM_DRIVER_EMAIL "dm@uk.sistina.com" + +/*----------------------------------------------------------------- + * The ioctl interface needs to be able to look up devices by + * name or uuid. + *---------------------------------------------------------------*/ +struct hash_cell { + struct list_head name_list; + struct list_head uuid_list; + + char *name; + char *uuid; + struct mapped_device *md; + struct dm_table *new_map; +}; + +#define NUM_BUCKETS 64 +#define MASK_BUCKETS (NUM_BUCKETS - 1) +static struct list_head _name_buckets[NUM_BUCKETS]; +static struct list_head _uuid_buckets[NUM_BUCKETS]; + +void dm_hash_remove_all(void); + +/* + * Guards access to all three tables. + */ +static DECLARE_RWSEM(_hash_lock); + +static void init_buckets(struct list_head *buckets) +{ + unsigned int i; + + for (i = 0; i < NUM_BUCKETS; i++) + INIT_LIST_HEAD(buckets + i); +} + +int dm_hash_init(void) +{ + init_buckets(_name_buckets); + init_buckets(_uuid_buckets); + devfs_mk_dir(DM_DIR); + return 0; +} + +void dm_hash_exit(void) +{ + dm_hash_remove_all(); + devfs_remove(DM_DIR); +} + +/*----------------------------------------------------------------- + * Hash function: + * We're not really concerned with the str hash function being + * fast since it's only used by the ioctl interface. + *---------------------------------------------------------------*/ +static unsigned int hash_str(const char *str) +{ + const unsigned int hash_mult = 2654435387U; + unsigned int h = 0; + + while (*str) + h = (h + (unsigned int) *str++) * hash_mult; + + return h & MASK_BUCKETS; +} + +/*----------------------------------------------------------------- + * Code for looking up a device by name + *---------------------------------------------------------------*/ +static struct hash_cell *__get_name_cell(const char *str) +{ + struct list_head *tmp; + struct hash_cell *hc; + unsigned int h = hash_str(str); + + list_for_each (tmp, _name_buckets + h) { + hc = list_entry(tmp, struct hash_cell, name_list); + if (!strcmp(hc->name, str)) + return hc; + } + + return NULL; +} + +static struct hash_cell *__get_uuid_cell(const char *str) +{ + struct list_head *tmp; + struct hash_cell *hc; + unsigned int h = hash_str(str); + + list_for_each (tmp, _uuid_buckets + h) { + hc = list_entry(tmp, struct hash_cell, uuid_list); + if (!strcmp(hc->uuid, str)) + return hc; + } + + return NULL; +} + +/*----------------------------------------------------------------- + * Inserting, removing and renaming a device. + *---------------------------------------------------------------*/ +static inline char *kstrdup(const char *str) +{ + char *r = kmalloc(strlen(str) + 1, GFP_KERNEL); + if (r) + strcpy(r, str); + return r; +} + +static struct hash_cell *alloc_cell(const char *name, const char *uuid, + struct mapped_device *md) +{ + struct hash_cell *hc; + + hc = kmalloc(sizeof(*hc), GFP_KERNEL); + if (!hc) + return NULL; + + hc->name = kstrdup(name); + if (!hc->name) { + kfree(hc); + return NULL; + } + + if (!uuid) + hc->uuid = NULL; + + else { + hc->uuid = kstrdup(uuid); + if (!hc->uuid) { + kfree(hc->name); + kfree(hc); + return NULL; + } + } + + INIT_LIST_HEAD(&hc->name_list); + INIT_LIST_HEAD(&hc->uuid_list); + hc->md = md; + hc->new_map = NULL; + return hc; +} + +static void free_cell(struct hash_cell *hc) +{ + if (hc) { + kfree(hc->name); + kfree(hc->uuid); + kfree(hc); + } +} + +/* + * devfs stuff. + */ +static int register_with_devfs(struct hash_cell *hc) +{ + struct gendisk *disk = dm_disk(hc->md); + + devfs_mk_bdev(MKDEV(disk->major, disk->first_minor), + S_IFBLK | S_IRUSR | S_IWUSR | S_IRGRP, + DM_DIR "/%s", hc->name); + return 0; +} + +static int unregister_with_devfs(struct hash_cell *hc) +{ + devfs_remove(DM_DIR"/%s", hc->name); + return 0; +} + +/* + * The kdev_t and uuid of a device can never change once it is + * initially inserted. + */ +int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md) +{ + struct hash_cell *cell; + + /* + * Allocate the new cells. + */ + cell = alloc_cell(name, uuid, md); + if (!cell) + return -ENOMEM; + + /* + * Insert the cell into all three hash tables. + */ + down_write(&_hash_lock); + if (__get_name_cell(name)) + goto bad; + + list_add(&cell->name_list, _name_buckets + hash_str(name)); + + if (uuid) { + if (__get_uuid_cell(uuid)) { + list_del(&cell->name_list); + goto bad; + } + list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid)); + } + register_with_devfs(cell); + dm_get(md); + up_write(&_hash_lock); + + return 0; + + bad: + up_write(&_hash_lock); + free_cell(cell); + return -EBUSY; +} + +void __hash_remove(struct hash_cell *hc) +{ + /* remove from the dev hash */ + list_del(&hc->uuid_list); + list_del(&hc->name_list); + unregister_with_devfs(hc); + dm_put(hc->md); + if (hc->new_map) + dm_table_put(hc->new_map); + free_cell(hc); +} + +void dm_hash_remove_all(void) +{ + int i; + struct hash_cell *hc; + struct list_head *tmp, *n; + + down_write(&_hash_lock); + for (i = 0; i < NUM_BUCKETS; i++) { + list_for_each_safe (tmp, n, _name_buckets + i) { + hc = list_entry(tmp, struct hash_cell, name_list); + __hash_remove(hc); + } + } + up_write(&_hash_lock); +} + +int dm_hash_rename(const char *old, const char *new) +{ + char *new_name, *old_name; + struct hash_cell *hc; + + /* + * duplicate new. + */ + new_name = kstrdup(new); + if (!new_name) + return -ENOMEM; + + down_write(&_hash_lock); + + /* + * Is new free ? + */ + hc = __get_name_cell(new); + if (hc) { + DMWARN("asked to rename to an already existing name %s -> %s", + old, new); + up_write(&_hash_lock); + kfree(new_name); + return -EBUSY; + } + + /* + * Is there such a device as 'old' ? + */ + hc = __get_name_cell(old); + if (!hc) { + DMWARN("asked to rename a non existent device %s -> %s", + old, new); + up_write(&_hash_lock); + kfree(new_name); + return -ENXIO; + } + + /* + * rename and move the name cell. + */ + list_del(&hc->name_list); + old_name = hc->name; + hc->name = new_name; + list_add(&hc->name_list, _name_buckets + hash_str(new_name)); + + /* rename the device node in devfs */ + unregister_with_devfs(hc); + register_with_devfs(hc); + + up_write(&_hash_lock); + kfree(old_name); + return 0; +} + +/*----------------------------------------------------------------- + * Implementation of the ioctl commands + *---------------------------------------------------------------*/ +/* + * All the ioctl commands get dispatched to functions with this + * prototype. + */ +typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size); + +static int remove_all(struct dm_ioctl *param, size_t param_size) +{ + dm_hash_remove_all(); + param->data_size = 0; + return 0; +} + +/* + * Round up the ptr to an 8-byte boundary. + */ +#define ALIGN_MASK 7 +static inline void *align_ptr(void *ptr) +{ + return (void *) (((size_t) (ptr + ALIGN_MASK)) & ~ALIGN_MASK); +} + +/* + * Retrieves the data payload buffer from an already allocated + * struct dm_ioctl. + */ +static void *get_result_buffer(struct dm_ioctl *param, size_t param_size, + size_t *len) +{ + param->data_start = align_ptr(param + 1) - (void *) param; + + if (param->data_start < param_size) + *len = param_size - param->data_start; + else + *len = 0; + + return ((void *) param) + param->data_start; +} + +static int list_devices(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; + + down_write(&_hash_lock); + + /* + * Loop through all the devices working out how much + * space we need. + */ + for (i = 0; i < NUM_BUCKETS; i++) { + list_for_each_entry (hc, _name_buckets + i, name_list) { + needed += sizeof(struct dm_name_list); + needed += strlen(hc->name); + needed += ALIGN_MASK; + } + } + + /* + * Grab our output buffer. + */ + nl = get_result_buffer(param, param_size, &len); + if (len < needed) { + param->flags |= DM_BUFFER_FULL_FLAG; + goto out; + } + param->data_size = param->data_start + needed; + + nl->dev = 0; /* Flags no data */ + + /* + * Now loop through filling out the names. + */ + for (i = 0; i < NUM_BUCKETS; i++) { + list_for_each_entry (hc, _name_buckets + i, name_list) { + if (old_nl) + old_nl->next = (__u32) ((void *) nl - + (void *) old_nl); + disk = dm_disk(hc->md); + nl->dev = MKDEV(disk->major, disk->first_minor); + nl->next = 0; + strcpy(nl->name, hc->name); + + old_nl = nl; + nl = align_ptr(((void *) ++nl) + strlen(hc->name) + 1); + } + } + + out: + up_write(&_hash_lock); + return 0; +} + +static int check_name(const char *name) +{ + if (strchr(name, '/')) { + DMWARN("invalid device name"); + return -EINVAL; + } + + return 0; +} + +/* + * Fills in a dm_ioctl structure, ready for sending back to + * userland. + */ +static int __dev_status(struct mapped_device *md, struct dm_ioctl *param) +{ + struct gendisk *disk = dm_disk(md); + struct dm_table *table; + struct block_device *bdev; + + param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG | + DM_ACTIVE_PRESENT_FLAG); + + if (dm_suspended(md)) + param->flags |= DM_SUSPEND_FLAG; + + bdev = bdget_disk(disk, 0); + if (!bdev) + return -ENXIO; + + param->dev = MKDEV(disk->major, disk->first_minor); + + /* + * Yes, this will be out of date by the time it gets back + * to userland, but it is still very useful ofr + * debugging. + */ + param->open_count = bdev->bd_openers; + bdput(bdev); + + if (disk->policy) + param->flags |= DM_READONLY_FLAG; + + param->event_nr = dm_get_event_nr(md); + + table = dm_get_table(md); + if (table) { + param->flags |= DM_ACTIVE_PRESENT_FLAG; + param->target_count = dm_table_get_num_targets(table); + dm_table_put(table); + } else + param->target_count = 0; + + return 0; +} + +static int dev_create(struct dm_ioctl *param, size_t param_size) +{ + int r; + struct mapped_device *md; + + r = check_name(param->name); + if (r) + return r; + + if (param->flags & DM_PERSISTENT_DEV_FLAG) + r = dm_create_with_minor(minor(to_kdev_t(param->dev)), &md); + else + r = dm_create(&md); + + if (r) + return r; + + r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md); + if (r) { + dm_put(md); + return r; + } + + param->flags &= ~DM_INACTIVE_PRESENT_FLAG; + + r = __dev_status(md, param); + dm_put(md); + + return r; +} + +/* + * Always use UUID for lookups if it's present, otherwise use name. + */ +static inline struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param) +{ + return *param->uuid ? + __get_uuid_cell(param->uuid) : __get_name_cell(param->name); +} + +static inline struct mapped_device *find_device(struct dm_ioctl *param) +{ + struct hash_cell *hc; + struct mapped_device *md = NULL; + + down_read(&_hash_lock); + hc = __find_device_hash_cell(param); + if (hc) { + md = hc->md; + + /* + * Sneakily write in both the name and the uuid + * while we have the cell. + */ + strncpy(param->name, hc->name, sizeof(param->name)); + if (hc->uuid) + strncpy(param->uuid, hc->uuid, sizeof(param->uuid)-1); + else + param->uuid[0] = '\0'; + + if (hc->new_map) + param->flags |= DM_INACTIVE_PRESENT_FLAG; + else + param->flags &= ~DM_INACTIVE_PRESENT_FLAG; + + dm_get(md); + } + up_read(&_hash_lock); + + return md; +} + +static int dev_remove(struct dm_ioctl *param, size_t param_size) +{ + struct hash_cell *hc; + + down_write(&_hash_lock); + hc = __find_device_hash_cell(param); + + if (!hc) { + DMWARN("device doesn't appear to be in the dev hash table."); + up_write(&_hash_lock); + return -ENXIO; + } + + __hash_remove(hc); + up_write(&_hash_lock); + param->data_size = 0; + return 0; +} + +/* + * Check a string doesn't overrun the chunk of + * memory we copied from userland. + */ +static int invalid_str(char *str, void *end) +{ + while ((void *) str < end) + if (!*str++) + return 0; + + return -EINVAL; +} + +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)) { + DMWARN("Invalid new logical volume name supplied."); + return -EINVAL; + } + + r = check_name(new_name); + if (r) + return r; + + param->data_size = 0; + return dm_hash_rename(param->name, new_name); +} + +static int suspend(struct dm_ioctl *param) +{ + int r = 0; + struct mapped_device *md; + + md = find_device(param); + if (!md) + return -ENXIO; + + if (!dm_suspended(md)) + r = dm_suspend(md); + + if (!r) + r = __dev_status(md, param); + + dm_put(md); + return r; +} + +static int resume(struct dm_ioctl *param) +{ + int r = 0; + struct hash_cell *hc; + struct mapped_device *md; + struct dm_table *new_map; + + down_write(&_hash_lock); + + hc = __find_device_hash_cell(param); + if (!hc) { + DMWARN("device doesn't appear to be in the dev hash table."); + up_write(&_hash_lock); + return -ENXIO; + } + + md = hc->md; + dm_get(md); + + new_map = hc->new_map; + hc->new_map = NULL; + param->flags &= ~DM_INACTIVE_PRESENT_FLAG; + + up_write(&_hash_lock); + + /* Do we need to load a new map ? */ + if (new_map) { + /* Suspend if it isn't already suspended */ + if (!dm_suspended(md)) + dm_suspend(md); + + r = dm_swap_table(md, new_map); + if (r) { + dm_put(md); + dm_table_put(new_map); + return r; + } + + if (!(dm_table_get_mode(new_map) & FMODE_WRITE)) + set_disk_ro(dm_disk(md), 1); + + dm_table_put(new_map); + } + + if (dm_suspended(md)) + r = dm_resume(md); + + if (!r) + r = __dev_status(md, param); + + dm_put(md); + return r; +} + +/* + * 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) +{ + if (param->flags & DM_SUSPEND_FLAG) + return suspend(param); + + return resume(param); +} + +/* + * 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) +{ + int r; + struct mapped_device *md; + + md = find_device(param); + if (!md) + return -ENXIO; + + r = __dev_status(md, param); + dm_put(md); + return r; +} + +/* + * Wait for a device to report an event + */ +static int dev_wait(struct dm_ioctl *param, size_t param_size) +{ + int r; + struct mapped_device *md; + DECLARE_WAITQUEUE(wq, current); + + md = find_device(param); + if (!md) + return -ENXIO; + + /* + * Wait for a notification event + */ + set_current_state(TASK_INTERRUPTIBLE); + if (!dm_add_wait_queue(md, &wq, param->event_nr)) { + schedule(); + dm_remove_wait_queue(md, &wq); + } + + /* + * The userland program is going to want to know what + * changed to trigger the event, so we may as well tell + * him and save an ioctl. + */ + r = __dev_status(md, param); + + dm_put(md); + return r; +} + +static inline int get_mode(struct dm_ioctl *param) +{ + int mode = FMODE_READ | FMODE_WRITE; + + if (param->flags & DM_READONLY_FLAG) + mode = FMODE_READ; + + return mode; +} + +static int next_target(struct dm_target_spec *last, __u32 next, void *end, + struct dm_target_spec **spec, char **target_params) +{ + *spec = (struct dm_target_spec *) ((unsigned char *) last + next); + *target_params = (char *) (*spec + 1); + + if (*spec < (last + 1)) + return -EINVAL; + + return invalid_str(*target_params, end); +} + +static int populate_table(struct dm_table *table, + struct dm_ioctl *param, size_t param_size) +{ + int r; + unsigned int i = 0; + struct dm_target_spec *spec = (struct dm_target_spec *) param; + __u32 next = param->data_start; + void *end = (void *) param + param_size; + char *target_params; + + if (!param->target_count) { + DMWARN("populate_table: no targets specified"); + return -EINVAL; + } + + for (i = 0; i < param->target_count; i++) { + + r = next_target(spec, next, end, &spec, &target_params); + if (r) { + DMWARN("unable to find target"); + return r; + } + + r = dm_table_add_target(table, spec->target_type, + (sector_t) spec->sector_start, + (sector_t) spec->length, + target_params); + if (r) { + DMWARN("error adding target to table"); + return r; + } + + next = spec->next; + } + + return dm_table_complete(table); +} + +static int table_load(struct dm_ioctl *param, size_t param_size) +{ + int r; + struct hash_cell *hc; + struct dm_table *t; + + r = dm_table_create(&t, get_mode(param)); + if (r) + return r; + + r = populate_table(t, param, param_size); + if (r) { + dm_table_put(t); + return r; + } + + down_write(&_hash_lock); + hc = __find_device_hash_cell(param); + if (!hc) { + DMWARN("device doesn't appear to be in the dev hash table."); + up_write(&_hash_lock); + return -ENXIO; + } + + hc->new_map = t; + param->flags |= DM_INACTIVE_PRESENT_FLAG; + + r = __dev_status(hc->md, param); + up_write(&_hash_lock); + return r; +} + +static int table_clear(struct dm_ioctl *param, size_t param_size) +{ + int r; + struct hash_cell *hc; + + down_write(&_hash_lock); + + hc = __find_device_hash_cell(param); + if (!hc) { + DMWARN("device doesn't appear to be in the dev hash table."); + up_write(&_hash_lock); + return -ENXIO; + } + + if (hc->new_map) { + dm_table_put(hc->new_map); + hc->new_map = NULL; + } + + param->flags &= ~DM_INACTIVE_PRESENT_FLAG; + + r = __dev_status(hc->md, param); + up_write(&_hash_lock); + return r; +} + +/* + * Retrieves a list of devices used by a particular dm device. + */ +static void retrieve_deps(struct dm_table *table, + struct dm_ioctl *param, size_t param_size) +{ + unsigned int count = 0; + struct list_head *tmp; + size_t len, needed; + struct dm_target_deps *deps; + + deps = get_result_buffer(param, param_size, &len); + + /* + * Count the devices. + */ + list_for_each(tmp, dm_table_get_devices(table)) + count++; + + /* + * Check we have enough space. + */ + needed = sizeof(*deps) + (sizeof(*deps->dev) * count); + if (len < needed) { + param->flags |= DM_BUFFER_FULL_FLAG; + return; + } + + /* + * Fill in the devices. + */ + deps->count = count; + count = 0; + list_for_each(tmp, dm_table_get_devices(table)) { + struct dm_dev *dd = list_entry(tmp, struct dm_dev, list); + deps->dev[count++] = dd->bdev->bd_dev; + } + + param->data_size = param->data_start + needed; +} + +static int table_deps(struct dm_ioctl *param, size_t param_size) +{ + int r = 0; + struct mapped_device *md; + struct dm_table *table; + + md = find_device(param); + if (!md) + return -ENXIO; + + r = __dev_status(md, param); + if (r) + goto out; + + table = dm_get_table(md); + if (table) { + retrieve_deps(table, param, param_size); + dm_table_put(table); + } + + out: + dm_put(md); + return r; +} + +/* + * Build up the status struct for each target + */ +static void retrieve_status(struct dm_table *table, + struct dm_ioctl *param, size_t param_size) +{ + unsigned int i, num_targets; + struct dm_target_spec *spec; + char *outbuf, *outptr; + status_type_t type; + size_t remaining, len, used = 0; + + outptr = outbuf = get_result_buffer(param, param_size, &len); + + if (param->flags & DM_STATUS_TABLE_FLAG) + type = STATUSTYPE_TABLE; + else + type = STATUSTYPE_INFO; + + /* Get all the target info */ + num_targets = dm_table_get_num_targets(table); + for (i = 0; i < num_targets; i++) { + struct dm_target *ti = dm_table_get_target(table, i); + + remaining = len - (outptr - outbuf); + if (remaining < sizeof(struct dm_target_spec)) { + param->flags |= DM_BUFFER_FULL_FLAG; + break; + } + + spec = (struct dm_target_spec *) outptr; + + spec->status = 0; + spec->sector_start = ti->begin; + spec->length = ti->len; + strncpy(spec->target_type, ti->type->name, + sizeof(spec->target_type)); + + outptr += sizeof(struct dm_target_spec); + remaining = len - (outptr - outbuf); + + /* Get the status/table string from the target driver */ + if (ti->type->status) { + if (ti->type->status(ti, type, outptr, remaining)) { + param->flags |= DM_BUFFER_FULL_FLAG; + break; + } + } else + outptr[0] = '\0'; + + outptr += strlen(outptr) + 1; + used = param->data_start + (outptr - outbuf); + + align_ptr(outptr); + spec->next = outptr - outbuf; + } + + if (used) + param->data_size = used; + + param->target_count = num_targets; +} + +/* + * 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) +{ + int r; + struct mapped_device *md; + struct dm_table *table; + + md = find_device(param); + if (!md) + return -ENXIO; + + r = __dev_status(md, param); + if (r) + goto out; + + table = dm_get_table(md); + if (table) { + retrieve_status(table, param, param_size); + dm_table_put(table); + } + + out: + dm_put(md); + return r; +} + +/*----------------------------------------------------------------- + * Implementation of open/close/ioctl on the special char + * device. + *---------------------------------------------------------------*/ +static ioctl_fn lookup_ioctl(unsigned int cmd) +{ + static struct { + int cmd; + ioctl_fn fn; + } _ioctls[] = { + {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */ + {DM_REMOVE_ALL_CMD, remove_all}, + {DM_LIST_DEVICES_CMD, list_devices}, + + {DM_DEV_CREATE_CMD, dev_create}, + {DM_DEV_REMOVE_CMD, dev_remove}, + {DM_DEV_RENAME_CMD, dev_rename}, + {DM_DEV_SUSPEND_CMD, dev_suspend}, + {DM_DEV_STATUS_CMD, dev_status}, + {DM_DEV_WAIT_CMD, dev_wait}, + + {DM_TABLE_LOAD_CMD, table_load}, + {DM_TABLE_CLEAR_CMD, table_clear}, + {DM_TABLE_DEPS_CMD, table_deps}, + {DM_TABLE_STATUS_CMD, table_status} + }; + + return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn; +} + +/* + * As well as checking the version compatibility this always + * copies the kernel interface version out. + */ +static int check_version(unsigned int cmd, struct dm_ioctl *user) +{ + __u32 version[3]; + int r = 0; + + if (copy_from_user(version, user->version, sizeof(version))) + return -EFAULT; + + if ((DM_VERSION_MAJOR != version[0]) || + (DM_VERSION_MINOR < version[1])) { + DMWARN("ioctl interface mismatch: " + "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)", + DM_VERSION_MAJOR, DM_VERSION_MINOR, + DM_VERSION_PATCHLEVEL, + version[0], version[1], version[2], cmd); + r = -EINVAL; + } + + /* + * Fill in the kernel version. + */ + version[0] = DM_VERSION_MAJOR; + version[1] = DM_VERSION_MINOR; + version[2] = DM_VERSION_PATCHLEVEL; + if (copy_to_user(user->version, version, sizeof(version))) + return -EFAULT; + + return r; +} + +static void free_params(struct dm_ioctl *param) +{ + vfree(param); +} + +static int copy_params(struct dm_ioctl *user, struct dm_ioctl **param) +{ + struct dm_ioctl tmp, *dmi; + + if (copy_from_user(&tmp, user, sizeof(tmp))) + return -EFAULT; + + if (tmp.data_size < sizeof(tmp)) + return -EINVAL; + + dmi = (struct dm_ioctl *) vmalloc(tmp.data_size); + if (!dmi) + return -ENOMEM; + + if (copy_from_user(dmi, user, tmp.data_size)) { + vfree(dmi); + return -EFAULT; + } + + *param = dmi; + return 0; +} + +static int validate_params(uint cmd, struct dm_ioctl *param) +{ + /* Always clear this flag */ + param->flags &= ~DM_BUFFER_FULL_FLAG; + + /* Ignores parameters */ + if (cmd == DM_REMOVE_ALL_CMD || cmd == DM_LIST_DEVICES_CMD) + return 0; + + /* Unless creating, either name or uuid but not both */ + if (cmd != DM_DEV_CREATE_CMD) { + if ((!*param->uuid && !*param->name) || + (*param->uuid && *param->name)) { + DMWARN("one of name or uuid must be supplied, cmd(%u)", + cmd); + return -EINVAL; + } + } + + /* Ensure strings are terminated */ + param->name[DM_NAME_LEN - 1] = '\0'; + param->uuid[DM_UUID_LEN - 1] = '\0'; + + return 0; +} + +static int ctl_ioctl(struct inode *inode, struct file *file, + uint command, ulong u) +{ + int r = 0; + unsigned int cmd; + struct dm_ioctl *param; + struct dm_ioctl *user = (struct dm_ioctl *) u; + ioctl_fn fn = NULL; + size_t param_size; + + /* only root can play with this */ + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + if (_IOC_TYPE(command) != DM_IOCTL) + return -ENOTTY; + + cmd = _IOC_NR(command); + + /* + * Check the interface version passed in. This also + * writes out the kernel's interface version. + */ + r = check_version(cmd, user); + if (r) + return r; + + /* + * Nothing more to do for the version command. + */ + if (cmd == DM_VERSION_CMD) + return 0; + + fn = lookup_ioctl(cmd); + if (!fn) { + DMWARN("dm_ctl_ioctl: unknown command 0x%x", command); + return -ENOTTY; + } + + /* + * Trying to avoid low memory issues when a device is + * suspended. + */ + current->flags |= PF_MEMALLOC; + + /* + * Copy the parameters into kernel space. + */ + r = copy_params(user, ¶m); + if (r) { + current->flags &= ~PF_MEMALLOC; + return r; + } + + /* + * FIXME: eventually we will remove the PF_MEMALLOC flag + * here. However the tools still do nasty things like + * 'load' while a device is suspended. + */ + + r = validate_params(cmd, param); + if (r) + goto out; + + param_size = param->data_size; + param->data_size = sizeof(*param); + r = fn(param, param_size); + + /* + * Copy the results back to userland. + */ + if (!r && copy_to_user(user, param, param->data_size)) + r = -EFAULT; + + out: + free_params(param); + current->flags &= ~PF_MEMALLOC; + return r; +} + +static struct file_operations _ctl_fops = { + .ioctl = ctl_ioctl, + .owner = THIS_MODULE, +}; + +static struct miscdevice _dm_misc = { + .minor = MISC_DYNAMIC_MINOR, + .name = DM_NAME, + .devfs_name = "mapper/control", + .fops = &_ctl_fops +}; + +/* + * Create misc character device and link to DM_DIR/control. + */ +int __init dm_interface_init(void) +{ + int r; + + r = dm_hash_init(); + if (r) + return r; + + r = misc_register(&_dm_misc); + if (r) { + DMERR("misc_register failed for control device"); + dm_hash_exit(); + return r; + } + + DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR, + DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA, + DM_DRIVER_EMAIL); + return 0; +} + +void dm_interface_exit(void) +{ + if (misc_deregister(&_dm_misc) < 0) + DMERR("misc_deregister failed for control device"); + + dm_hash_exit(); +} --- diff/include/linux/dm-ioctl-v1.h 1970-01-01 01:00:00.000000000 +0100 +++ source/include/linux/dm-ioctl-v1.h 2003-07-01 15:36:42.000000000 +0100 @@ -0,0 +1,149 @@ +/* + * Copyright (C) 2001 Sistina Software (UK) Limited. + * + * This file is released under the LGPL. + */ + +#ifndef _LINUX_DM_IOCTL_V1_H +#define _LINUX_DM_IOCTL_V1_H + +#include + +#define DM_DIR "mapper" /* Slashes not supported */ +#define DM_MAX_TYPE_NAME 16 +#define DM_NAME_LEN 128 +#define DM_UUID_LEN 129 + +/* + * Implements a traditional ioctl interface to the device mapper. + */ + +/* + * All ioctl arguments consist of a single chunk of memory, with + * this structure at the start. If a uuid is specified any + * lookup (eg. for a DM_INFO) will be done on that, *not* the + * name. + */ +struct dm_ioctl { + /* + * The version number is made up of three parts: + * major - no backward or forward compatibility, + * minor - only backwards compatible, + * patch - both backwards and forwards compatible. + * + * All clients of the ioctl interface should fill in the + * version number of the interface that they were + * compiled with. + * + * All recognised ioctl commands (ie. those that don't + * return -ENOTTY) fill out this field, even if the + * command failed. + */ + uint32_t version[3]; /* in/out */ + uint32_t data_size; /* total size of data passed in + * including this struct */ + + uint32_t data_start; /* offset to start of data + * relative to start of this struct */ + + uint32_t target_count; /* in/out */ + uint32_t open_count; /* out */ + uint32_t flags; /* in/out */ + + __kernel_dev_t dev; /* in/out */ + + char name[DM_NAME_LEN]; /* device name */ + char uuid[DM_UUID_LEN]; /* unique identifier for + * the block device */ +}; + +/* + * Used to specify tables. These structures appear after the + * dm_ioctl. + */ +struct dm_target_spec { + int32_t status; /* used when reading from kernel only */ + uint64_t sector_start; + uint32_t length; + + /* + * Offset in bytes (from the start of this struct) to + * next target_spec. + */ + uint32_t next; + + char target_type[DM_MAX_TYPE_NAME]; + + /* + * Parameter string starts immediately after this object. + * Be careful to add padding after string to ensure correct + * alignment of subsequent dm_target_spec. + */ +}; + +/* + * Used to retrieve the target dependencies. + */ +struct dm_target_deps { + uint32_t count; + + __kernel_dev_t dev[0]; /* out */ +}; + +/* + * If you change this make sure you make the corresponding change + * to dm-ioctl.c:lookup_ioctl() + */ +enum { + /* Top level cmds */ + DM_VERSION_CMD = 0, + DM_REMOVE_ALL_CMD, + + /* device level cmds */ + DM_DEV_CREATE_CMD, + DM_DEV_REMOVE_CMD, + DM_DEV_RELOAD_CMD, + DM_DEV_RENAME_CMD, + DM_DEV_SUSPEND_CMD, + DM_DEV_DEPS_CMD, + DM_DEV_STATUS_CMD, + + /* target level cmds */ + DM_TARGET_STATUS_CMD, + DM_TARGET_WAIT_CMD +}; + +#define DM_IOCTL 0xfd + +#define DM_VERSION _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl) +#define DM_REMOVE_ALL _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl) + +#define DM_DEV_CREATE _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, struct dm_ioctl) +#define DM_DEV_REMOVE _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, struct dm_ioctl) +#define DM_DEV_RELOAD _IOWR(DM_IOCTL, DM_DEV_RELOAD_CMD, struct dm_ioctl) +#define DM_DEV_SUSPEND _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl) +#define DM_DEV_RENAME _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, struct dm_ioctl) +#define DM_DEV_DEPS _IOWR(DM_IOCTL, DM_DEV_DEPS_CMD, struct dm_ioctl) +#define DM_DEV_STATUS _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl) + +#define DM_TARGET_STATUS _IOWR(DM_IOCTL, DM_TARGET_STATUS_CMD, struct dm_ioctl) +#define DM_TARGET_WAIT _IOWR(DM_IOCTL, DM_TARGET_WAIT_CMD, struct dm_ioctl) + +#define DM_VERSION_MAJOR 1 +#define DM_VERSION_MINOR 0 +#define DM_VERSION_PATCHLEVEL 6 +#define DM_VERSION_EXTRA "-ioctl (2002-10-15)" + +/* Status bits */ +#define DM_READONLY_FLAG 0x00000001 +#define DM_SUSPEND_FLAG 0x00000002 +#define DM_EXISTS_FLAG 0x00000004 +#define DM_PERSISTENT_DEV_FLAG 0x00000008 + +/* + * Flag passed into ioctl STATUS command to get table information + * rather than current status. + */ +#define DM_STATUS_TABLE_FLAG 0x00000010 + +#endif /* _LINUX_DM_IOCTL_H */ --- diff/include/linux/dm-ioctl-v4.h 1970-01-01 01:00:00.000000000 +0100 +++ source/include/linux/dm-ioctl-v4.h 2003-07-01 15:36:42.000000000 +0100 @@ -0,0 +1,237 @@ +/* + * Copyright (C) 2001 - 2003 Sistina Software (UK) Limited. + * + * This file is released under the LGPL. + */ + +#ifndef _LINUX_DM_IOCTL_V4_H +#define _LINUX_DM_IOCTL_V4_H + +#include + +#define DM_DIR "mapper" /* Slashes not supported */ +#define DM_MAX_TYPE_NAME 16 +#define DM_NAME_LEN 128 +#define DM_UUID_LEN 129 + +/* + * A traditional ioctl interface for the device mapper. + * + * Each device can have two tables associated with it, an + * 'active' table which is the one currently used by io passing + * through the device, and an 'inactive' one which is a table + * that is being prepared as a replacement for the 'active' one. + * + * DM_VERSION: + * Just get the version information for the ioctl interface. + * + * DM_REMOVE_ALL: + * Remove all dm devices, destroy all tables. Only really used + * for debug. + * + * DM_LIST_DEVICES: + * Get a list of all the dm device names. + * + * DM_DEV_CREATE: + * Create a new device, neither the 'active' or 'inactive' table + * slots will be filled. The device will be in suspended state + * after creation, however any io to the device will get errored + * since it will be out-of-bounds. + * + * DM_DEV_REMOVE: + * Remove a device, destroy any tables. + * + * DM_DEV_RENAME: + * Rename a device. + * + * DM_SUSPEND: + * This performs both suspend and resume, depending which flag is + * passed in. + * Suspend: This command will not return until all pending io to + * the device has completed. Further io will be deferred until + * the device is resumed. + * Resume: It is no longer an error to issue this command on an + * unsuspended device. If a table is present in the 'inactive' + * slot, it will be moved to the active slot, then the old table + * from the active slot will be _destroyed_. Finally the device + * is resumed. + * + * DM_DEV_STATUS: + * Retrieves the status for the table in the 'active' slot. + * + * DM_DEV_WAIT: + * Wait for a significant event to occur to the device. This + * could either be caused by an event triggered by one of the + * targets of the table in the 'active' slot, or a table change. + * + * DM_TABLE_LOAD: + * Load a table into the 'inactive' slot for the device. The + * device does _not_ need to be suspended prior to this command. + * + * DM_TABLE_CLEAR: + * Destroy any table in the 'inactive' slot (ie. abort). + * + * DM_TABLE_DEPS: + * Return a set of device dependencies for the 'active' table. + * + * DM_TABLE_STATUS: + * Return the targets status for the 'active' table. + */ + +/* + * All ioctl arguments consist of a single chunk of memory, with + * this structure at the start. If a uuid is specified any + * lookup (eg. for a DM_INFO) will be done on that, *not* the + * name. + */ +struct dm_ioctl { + /* + * The version number is made up of three parts: + * major - no backward or forward compatibility, + * minor - only backwards compatible, + * patch - both backwards and forwards compatible. + * + * All clients of the ioctl interface should fill in the + * version number of the interface that they were + * compiled with. + * + * All recognised ioctl commands (ie. those that don't + * return -ENOTTY) fill out this field, even if the + * command failed. + */ + __u32 version[3]; /* in/out */ + __u32 data_size; /* total size of data passed in + * including this struct */ + + __u32 data_start; /* offset to start of data + * relative to start of this struct */ + + __u32 target_count; /* in/out */ + __s32 open_count; /* out */ + __u32 flags; /* in/out */ + __u32 event_nr; /* in/out */ + __u32 padding; + + __u64 dev; /* in/out */ + + char name[DM_NAME_LEN]; /* device name */ + char uuid[DM_UUID_LEN]; /* unique identifier for + * the block device */ +}; + +/* + * Used to specify tables. These structures appear after the + * dm_ioctl. + */ +struct dm_target_spec { + __u64 sector_start; + __u64 length; + __s32 status; /* used when reading from kernel only */ + + /* + * Offset in bytes (from the start of this struct) to + * next target_spec. + */ + __u32 next; + + char target_type[DM_MAX_TYPE_NAME]; + + /* + * Parameter string starts immediately after this object. + * Be careful to add padding after string to ensure correct + * alignment of subsequent dm_target_spec. + */ +}; + +/* + * Used to retrieve the target dependencies. + */ +struct dm_target_deps { + __u32 count; /* Array size */ + __u32 padding; /* unused */ + __u64 dev[0]; /* out */ +}; + +/* + * Used to get a list of all dm devices. + */ +struct dm_name_list { + __u64 dev; + __u32 next; /* offset to the next record from + the _start_ of this */ + char name[0]; +}; + +/* + * If you change this make sure you make the corresponding change + * to dm-ioctl.c:lookup_ioctl() + */ +enum { + /* Top level cmds */ + DM_VERSION_CMD = 0, + DM_REMOVE_ALL_CMD, + DM_LIST_DEVICES_CMD, + + /* device level cmds */ + DM_DEV_CREATE_CMD, + DM_DEV_REMOVE_CMD, + DM_DEV_RENAME_CMD, + DM_DEV_SUSPEND_CMD, + DM_DEV_STATUS_CMD, + DM_DEV_WAIT_CMD, + + /* Table level cmds */ + DM_TABLE_LOAD_CMD, + DM_TABLE_CLEAR_CMD, + DM_TABLE_DEPS_CMD, + DM_TABLE_STATUS_CMD, +}; + +#define DM_IOCTL 0xfd + +#define DM_VERSION _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl) +#define DM_REMOVE_ALL _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl) +#define DM_LIST_DEVICES _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, struct dm_ioctl) + +#define DM_DEV_CREATE _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, struct dm_ioctl) +#define DM_DEV_REMOVE _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, struct dm_ioctl) +#define DM_DEV_RENAME _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, struct dm_ioctl) +#define DM_DEV_SUSPEND _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl) +#define DM_DEV_STATUS _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl) +#define DM_DEV_WAIT _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, struct dm_ioctl) + +#define DM_TABLE_LOAD _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, struct dm_ioctl) +#define DM_TABLE_CLEAR _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, struct dm_ioctl) +#define DM_TABLE_DEPS _IOWR(DM_IOCTL, DM_TABLE_DEPS_CMD, struct dm_ioctl) +#define DM_TABLE_STATUS _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, struct dm_ioctl) + +#define DM_VERSION_MAJOR 4 +#define DM_VERSION_MINOR 0 +#define DM_VERSION_PATCHLEVEL 0 +#define DM_VERSION_EXTRA "-ioctl (2003-06-04)" + +/* Status bits */ +#define DM_READONLY_FLAG (1 << 0) /* In/Out */ +#define DM_SUSPEND_FLAG (1 << 1) /* In/Out */ +#define DM_PERSISTENT_DEV_FLAG (1 << 3) /* In */ + +/* + * Flag passed into ioctl STATUS command to get table information + * rather than current status. + */ +#define DM_STATUS_TABLE_FLAG (1 << 4) /* In */ + +/* + * Flags that indicate whether a table is present in either of + * the two table slots that a device has. + */ +#define DM_ACTIVE_PRESENT_FLAG (1 << 5) /* Out */ +#define DM_INACTIVE_PRESENT_FLAG (1 << 6) /* Out */ + +/* + * Indicates that the buffer passed in wasn't big enough for the + * results. + */ +#define DM_BUFFER_FULL_FLAG (1 << 8) /* Out */ + +#endif /* _LINUX_DM_IOCTL_H */ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/