/* * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved. * Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved. * * This file is part of the device-mapper userspace tools. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU Lesser General Public License v.2.1. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #ifndef LIB_DEVICE_MAPPER_H #define LIB_DEVICE_MAPPER_H #include #include #include #ifdef linux # include #endif #include #include #include #include #ifndef __GNUC__ # define __typeof__ typeof #endif #ifdef __cplusplus extern "C" { #endif /***************************************************************** * The first section of this file provides direct access to the * individual device-mapper ioctls. Since it is quite laborious to * build the ioctl arguments for the device-mapper, people are * encouraged to use this library. ****************************************************************/ /* * The library user may wish to register their own * logging function. By default errors go to stderr. * Use dm_log_with_errno_init(NULL) to restore the default log fn. */ typedef void (*dm_log_with_errno_fn) (int level, const char *file, int line, int dm_errno, const char *f, ...) __attribute__ ((format(printf, 5, 6))); void dm_log_with_errno_init(dm_log_with_errno_fn fn); void dm_log_init_verbose(int level); /* * Original version of this function. * dm_errno is set to 0. * * Deprecated: Use the _with_errno_ versions above instead. */ typedef void (*dm_log_fn) (int level, const char *file, int line, const char *f, ...) __attribute__ ((format(printf, 4, 5))); void dm_log_init(dm_log_fn fn); /* * For backward-compatibility, indicate that dm_log_init() was used * to set a non-default value of dm_log(). */ int dm_log_is_non_default(void); /* * Number of devices currently in suspended state (via the library). */ int dm_get_suspended_counter(void); enum { DM_DEVICE_CREATE, DM_DEVICE_RELOAD, DM_DEVICE_REMOVE, DM_DEVICE_REMOVE_ALL, DM_DEVICE_SUSPEND, DM_DEVICE_RESUME, DM_DEVICE_INFO, DM_DEVICE_DEPS, DM_DEVICE_RENAME, DM_DEVICE_VERSION, DM_DEVICE_STATUS, DM_DEVICE_TABLE, DM_DEVICE_WAITEVENT, DM_DEVICE_LIST, DM_DEVICE_CLEAR, DM_DEVICE_MKNODES, DM_DEVICE_LIST_VERSIONS, DM_DEVICE_TARGET_MSG, DM_DEVICE_SET_GEOMETRY }; /* * You will need to build a struct dm_task for * each ioctl command you want to execute. */ struct dm_task; struct dm_task *dm_task_create(int type); void dm_task_destroy(struct dm_task *dmt); int dm_task_set_name(struct dm_task *dmt, const char *name); int dm_task_set_uuid(struct dm_task *dmt, const char *uuid); /* * Retrieve attributes after an info. */ struct dm_info { int exists; int suspended; int live_table; int inactive_table; int32_t open_count; uint32_t event_nr; uint32_t major; uint32_t minor; /* minor device number */ int read_only; /* 0:read-write; 1:read-only */ int32_t target_count; }; struct dm_deps { uint32_t count; uint32_t filler; uint64_t device[0]; }; struct dm_names { uint64_t dev; uint32_t next; /* Offset to next struct from start of this struct */ char name[0]; }; struct dm_versions { uint32_t next; /* Offset to next struct from start of this struct */ uint32_t version[3]; char name[0]; }; int dm_get_library_version(char *version, size_t size); int dm_task_get_driver_version(struct dm_task *dmt, char *version, size_t size); int dm_task_get_info(struct dm_task *dmt, struct dm_info *dmi); const char *dm_task_get_name(const struct dm_task *dmt); const char *dm_task_get_uuid(const struct dm_task *dmt); struct dm_deps *dm_task_get_deps(struct dm_task *dmt); struct dm_names *dm_task_get_names(struct dm_task *dmt); struct dm_versions *dm_task_get_versions(struct dm_task *dmt); int dm_task_set_ro(struct dm_task *dmt); int dm_task_set_newname(struct dm_task *dmt, const char *newname); int dm_task_set_newuuid(struct dm_task *dmt, const char *newuuid); int dm_task_set_minor(struct dm_task *dmt, int minor); int dm_task_set_major(struct dm_task *dmt, int major); int dm_task_set_major_minor(struct dm_task *dmt, int major, int minor, int allow_default_major_fallback); int dm_task_set_uid(struct dm_task *dmt, uid_t uid); int dm_task_set_gid(struct dm_task *dmt, gid_t gid); int dm_task_set_mode(struct dm_task *dmt, mode_t mode); int dm_task_set_cookie(struct dm_task *dmt, uint32_t *cookie, uint16_t flags); int dm_task_set_event_nr(struct dm_task *dmt, uint32_t event_nr); int dm_task_set_geometry(struct dm_task *dmt, const char *cylinders, const char *heads, const char *sectors, const char *start); int dm_task_set_message(struct dm_task *dmt, const char *message); int dm_task_set_sector(struct dm_task *dmt, uint64_t sector); int dm_task_no_flush(struct dm_task *dmt); int dm_task_no_open_count(struct dm_task *dmt); int dm_task_skip_lockfs(struct dm_task *dmt); int dm_task_query_inactive_table(struct dm_task *dmt); int dm_task_suppress_identical_reload(struct dm_task *dmt); int dm_task_secure_data(struct dm_task *dmt); /* * Enable checks for common mistakes such as issuing ioctls in an unsafe order. */ int dm_task_enable_checks(struct dm_task *dmt); typedef enum { DM_ADD_NODE_ON_RESUME, /* add /dev/mapper node with dmsetup resume */ DM_ADD_NODE_ON_CREATE /* add /dev/mapper node with dmsetup create */ } dm_add_node_t; int dm_task_set_add_node(struct dm_task *dmt, dm_add_node_t add_node); /* * Control read_ahead. */ #define DM_READ_AHEAD_AUTO UINT32_MAX /* Use kernel default readahead */ #define DM_READ_AHEAD_NONE 0 /* Disable readahead */ #define DM_READ_AHEAD_MINIMUM_FLAG 0x1 /* Value supplied is minimum */ /* * Read ahead is set with DM_DEVICE_CREATE with a table or DM_DEVICE_RESUME. */ int dm_task_set_read_ahead(struct dm_task *dmt, uint32_t read_ahead, uint32_t read_ahead_flags); uint32_t dm_task_get_read_ahead(const struct dm_task *dmt, uint32_t *read_ahead); /* * Use these to prepare for a create or reload. */ int dm_task_add_target(struct dm_task *dmt, uint64_t start, uint64_t size, const char *ttype, const char *params); /* * Format major/minor numbers correctly for input to driver. */ #define DM_FORMAT_DEV_BUFSIZE 13 /* Minimum bufsize to handle worst case. */ int dm_format_dev(char *buf, int bufsize, uint32_t dev_major, uint32_t dev_minor); /* Use this to retrive target information returned from a STATUS call */ void *dm_get_next_target(struct dm_task *dmt, void *next, uint64_t *start, uint64_t *length, char **target_type, char **params); /* * Call this to actually run the ioctl. */ int dm_task_run(struct dm_task *dmt); /* * Call this to make or remove the device nodes associated with previously * issued commands. */ void dm_task_update_nodes(void); /* * Configure the device-mapper directory */ int dm_set_dev_dir(const char *dir); const char *dm_dir(void); /* * Determine whether a major number belongs to device-mapper or not. */ int dm_is_dm_major(uint32_t major); /* * Release library resources */ void dm_lib_release(void); void dm_lib_exit(void) __attribute__((destructor)); /* * Use NULL for all devices. */ int dm_mknodes(const char *name); int dm_driver_version(char *version, size_t size); /****************************************************** * Functions to build and manipulate trees of devices * ******************************************************/ struct dm_tree; struct dm_tree_node; /* * Initialise an empty dependency tree. * * The tree consists of a root node together with one node for each mapped * device which has child nodes for each device referenced in its table. * * Every node in the tree has one or more children and one or more parents. * * The root node is the parent/child of every node that doesn't have other * parents/children. */ struct dm_tree *dm_tree_create(void); void dm_tree_free(struct dm_tree *tree); /* * Add nodes to the tree for a given device and all the devices it uses. */ int dm_tree_add_dev(struct dm_tree *tree, uint32_t major, uint32_t minor); int dm_tree_add_dev_with_udev_flags(struct dm_tree *tree, uint32_t major, uint32_t minor, uint16_t udev_flags); /* * Add a new node to the tree if it doesn't already exist. */ struct dm_tree_node *dm_tree_add_new_dev(struct dm_tree *tree, const char *name, const char *uuid, uint32_t major, uint32_t minor, int read_only, int clear_inactive, void *context); struct dm_tree_node *dm_tree_add_new_dev_with_udev_flags(struct dm_tree *tree, const char *name, const char *uuid, uint32_t major, uint32_t minor, int read_only, int clear_inactive, void *context, uint16_t udev_flags); /* * Search for a node in the tree. * Set major and minor to 0 or uuid to NULL to get the root node. */ struct dm_tree_node *dm_tree_find_node(struct dm_tree *tree, uint32_t major, uint32_t minor); struct dm_tree_node *dm_tree_find_node_by_uuid(struct dm_tree *tree, const char *uuid); /* * Use this to walk through all children of a given node. * Set handle to NULL in first call. * Returns NULL after the last child. * Set inverted to use inverted tree. */ struct dm_tree_node *dm_tree_next_child(void **handle, const struct dm_tree_node *parent, uint32_t inverted); /* * Get properties of a node. */ const char *dm_tree_node_get_name(const struct dm_tree_node *node); const char *dm_tree_node_get_uuid(const struct dm_tree_node *node); const struct dm_info *dm_tree_node_get_info(const struct dm_tree_node *node); void *dm_tree_node_get_context(const struct dm_tree_node *node); int dm_tree_node_size_changed(const struct dm_tree_node *dnode); /* * Returns the number of children of the given node (excluding the root node). * Set inverted for the number of parents. */ int dm_tree_node_num_children(const struct dm_tree_node *node, uint32_t inverted); /* * Deactivate a device plus all dependencies. * Ignores devices that don't have a uuid starting with uuid_prefix. */ int dm_tree_deactivate_children(struct dm_tree_node *dnode, const char *uuid_prefix, size_t uuid_prefix_len); /* * Preload/create a device plus all dependencies. * Ignores devices that don't have a uuid starting with uuid_prefix. */ int dm_tree_preload_children(struct dm_tree_node *dnode, const char *uuid_prefix, size_t uuid_prefix_len); /* * Resume a device plus all dependencies. * Ignores devices that don't have a uuid starting with uuid_prefix. */ int dm_tree_activate_children(struct dm_tree_node *dnode, const char *uuid_prefix, size_t uuid_prefix_len); /* * Suspend a device plus all dependencies. * Ignores devices that don't have a uuid starting with uuid_prefix. */ int dm_tree_suspend_children(struct dm_tree_node *dnode, const char *uuid_prefix, size_t uuid_prefix_len); /* * Skip the filesystem sync when suspending. * Does nothing with other functions. * Use this when no snapshots are involved. */ void dm_tree_skip_lockfs(struct dm_tree_node *dnode); /* * Set the 'noflush' flag when suspending devices. * If the kernel supports it, instead of erroring outstanding I/O that * cannot be completed, the I/O is queued and resubmitted when the * device is resumed. This affects multipath devices when all paths * have failed and queue_if_no_path is set, and mirror devices when * block_on_error is set and the mirror log has failed. */ void dm_tree_use_no_flush_suspend(struct dm_tree_node *dnode); /* * Is the uuid prefix present in the tree? * Only returns 0 if every node was checked successfully. * Returns 1 if the tree walk has to be aborted. */ int dm_tree_children_use_uuid(struct dm_tree_node *dnode, const char *uuid_prefix, size_t uuid_prefix_len); /* * Construct tables for new nodes before activating them. */ int dm_tree_node_add_snapshot_origin_target(struct dm_tree_node *dnode, uint64_t size, const char *origin_uuid); int dm_tree_node_add_snapshot_target(struct dm_tree_node *node, uint64_t size, const char *origin_uuid, const char *cow_uuid, int persistent, uint32_t chunk_size); int dm_tree_node_add_snapshot_merge_target(struct dm_tree_node *node, uint64_t size, const char *origin_uuid, const char *cow_uuid, const char *merge_uuid, uint32_t chunk_size); int dm_tree_node_add_error_target(struct dm_tree_node *node, uint64_t size); int dm_tree_node_add_zero_target(struct dm_tree_node *node, uint64_t size); int dm_tree_node_add_linear_target(struct dm_tree_node *node, uint64_t size); int dm_tree_node_add_striped_target(struct dm_tree_node *node, uint64_t size, uint32_t stripe_size); #define DM_CRYPT_IV_DEFAULT UINT64_C(-1) /* iv_offset == seg offset */ /* * Function accepts one string in cipher specification * (chainmode and iv should be NULL because included in cipher string) * or * separate arguments which will be joined to "cipher-chainmode-iv" */ int dm_tree_node_add_crypt_target(struct dm_tree_node *node, uint64_t size, const char *cipher, const char *chainmode, const char *iv, uint64_t iv_offset, const char *key); int dm_tree_node_add_mirror_target(struct dm_tree_node *node, uint64_t size); /* Mirror log flags */ #define DM_NOSYNC 0x00000001 /* Known already in sync */ #define DM_FORCESYNC 0x00000002 /* Force resync */ #define DM_BLOCK_ON_ERROR 0x00000004 /* On error, suspend I/O */ #define DM_CORELOG 0x00000008 /* In-memory log */ int dm_tree_node_add_mirror_target_log(struct dm_tree_node *node, uint32_t region_size, unsigned clustered, const char *log_uuid, unsigned area_count, uint32_t flags); /* * Replicator operation mode * Note: API for Replicator is not yet stable */ typedef enum { DM_REPLICATOR_SYNC, /* Synchronous replication */ DM_REPLICATOR_ASYNC_WARN, /* Warn if async replicator is slow */ DM_REPLICATOR_ASYNC_STALL, /* Stall replicator if not fast enough */ DM_REPLICATOR_ASYNC_DROP, /* Drop sites out of sync */ DM_REPLICATOR_ASYNC_FAIL, /* Fail replicator if slow */ NUM_DM_REPLICATOR_MODES } dm_replicator_mode_t; int dm_tree_node_add_replicator_target(struct dm_tree_node *node, uint64_t size, const char *rlog_uuid, const char *rlog_type, unsigned rsite_index, dm_replicator_mode_t mode, uint32_t async_timeout, uint64_t fall_behind_data, uint32_t fall_behind_ios); int dm_tree_node_add_replicator_dev_target(struct dm_tree_node *node, uint64_t size, const char *replicator_uuid, /* Replicator control device */ uint64_t rdevice_index, const char *rdev_uuid, /* Rimage device name/uuid */ unsigned rsite_index, const char *slog_uuid, uint32_t slog_flags, /* Mirror log flags */ uint32_t slog_region_size); /* End of Replicator API */ void dm_tree_node_set_presuspend_node(struct dm_tree_node *node, struct dm_tree_node *presuspend_node); int dm_tree_node_add_target_area(struct dm_tree_node *node, const char *dev_name, const char *dlid, uint64_t offset); /* * Set readahead (in sectors) after loading the node. */ void dm_tree_node_set_read_ahead(struct dm_tree_node *dnode, uint32_t read_ahead, uint32_t read_ahead_flags); void dm_tree_set_cookie(struct dm_tree_node *node, uint32_t cookie); uint32_t dm_tree_get_cookie(struct dm_tree_node *node); /***************************************************************************** * Library functions *****************************************************************************/ /******************* * Memory management *******************/ void *dm_malloc_aux(size_t s, const char *file, int line); void *dm_malloc_aux_debug(size_t s, const char *file, int line); void *dm_zalloc_aux(size_t s, const char *file, int line); void *dm_zalloc_aux_debug(size_t s, const char *file, int line); char *dm_strdup_aux(const char *str, const char *file, int line); void dm_free_aux(void *p); void *dm_realloc_aux(void *p, unsigned int s, const char *file, int line); int dm_dump_memory_debug(void); void dm_bounds_check_debug(void); #ifdef DEBUG_MEM # define dm_malloc(s) dm_malloc_aux_debug((s), __FILE__, __LINE__) # define dm_zalloc(s) dm_zalloc_aux_debug((s), __FILE__, __LINE__) # define dm_strdup(s) dm_strdup_aux((s), __FILE__, __LINE__) # define dm_free(p) dm_free_aux(p) # define dm_realloc(p, s) dm_realloc_aux(p, s, __FILE__, __LINE__) # define dm_dump_memory() dm_dump_memory_debug() # define dm_bounds_check() dm_bounds_check_debug() #else # define dm_malloc(s) dm_malloc_aux((s), __FILE__, __LINE__) # define dm_zalloc(s) dm_zalloc_aux((s), __FILE__, __LINE__) # define dm_strdup(s) strdup(s) # define dm_free(p) free(p) # define dm_realloc(p, s) realloc(p, s) # define dm_dump_memory() {} # define dm_bounds_check() {} #endif /* * The pool allocator is useful when you are going to allocate * lots of memory, use the memory for a bit, and then free the * memory in one go. A surprising amount of code has this usage * profile. * * You should think of the pool as an infinite, contiguous chunk * of memory. The front of this chunk of memory contains * allocated objects, the second half is free. dm_pool_alloc grabs * the next 'size' bytes from the free half, in effect moving it * into the allocated half. This operation is very efficient. * * dm_pool_free frees the allocated object *and* all objects * allocated after it. It is important to note this semantic * difference from malloc/free. This is also extremely * efficient, since a single dm_pool_free can dispose of a large * complex object. * * dm_pool_destroy frees all allocated memory. * * eg, If you are building a binary tree in your program, and * know that you are only ever going to insert into your tree, * and not delete (eg, maintaining a symbol table for a * compiler). You can create yourself a pool, allocate the nodes * from it, and when the tree becomes redundant call dm_pool_destroy * (no nasty iterating through the tree to free nodes). * * eg, On the other hand if you wanted to repeatedly insert and * remove objects into the tree, you would be better off * allocating the nodes from a free list; you cannot free a * single arbitrary node with pool. */ struct dm_pool; /* constructor and destructor */ struct dm_pool *dm_pool_create(const char *name, size_t chunk_hint); void dm_pool_destroy(struct dm_pool *p); /* simple allocation/free routines */ void *dm_pool_alloc(struct dm_pool *p, size_t s); void *dm_pool_alloc_aligned(struct dm_pool *p, size_t s, unsigned alignment); void dm_pool_empty(struct dm_pool *p); void dm_pool_free(struct dm_pool *p, void *ptr); /* * Object building routines: * * These allow you to 'grow' an object, useful for * building strings, or filling in dynamic * arrays. * * It's probably best explained with an example: * * char *build_string(struct dm_pool *mem) * { * int i; * char buffer[16]; * * if (!dm_pool_begin_object(mem, 128)) * return NULL; * * for (i = 0; i < 50; i++) { * snprintf(buffer, sizeof(buffer), "%d, ", i); * if (!dm_pool_grow_object(mem, buffer, 0)) * goto bad; * } * * // add null * if (!dm_pool_grow_object(mem, "\0", 1)) * goto bad; * * return dm_pool_end_object(mem); * * bad: * * dm_pool_abandon_object(mem); * return NULL; *} * * So start an object by calling dm_pool_begin_object * with a guess at the final object size - if in * doubt make the guess too small. * * Then append chunks of data to your object with * dm_pool_grow_object. Finally get your object with * a call to dm_pool_end_object. * * Setting delta to 0 means it will use strlen(extra). */ int dm_pool_begin_object(struct dm_pool *p, size_t hint); int dm_pool_grow_object(struct dm_pool *p, const void *extra, size_t delta); void *dm_pool_end_object(struct dm_pool *p); void dm_pool_abandon_object(struct dm_pool *p); /* utilities */ char *dm_pool_strdup(struct dm_pool *p, const char *str); char *dm_pool_strndup(struct dm_pool *p, const char *str, size_t n); void *dm_pool_zalloc(struct dm_pool *p, size_t s); /****************** * bitset functions ******************/ typedef uint32_t *dm_bitset_t; dm_bitset_t dm_bitset_create(struct dm_pool *mem, unsigned num_bits); void dm_bitset_destroy(dm_bitset_t bs); int dm_bitset_equal(dm_bitset_t in1, dm_bitset_t in2); void dm_bit_and(dm_bitset_t out, dm_bitset_t in1, dm_bitset_t in2); void dm_bit_union(dm_bitset_t out, dm_bitset_t in1, dm_bitset_t in2); int dm_bit_get_first(dm_bitset_t bs); int dm_bit_get_next(dm_bitset_t bs, int last_bit); #define DM_BITS_PER_INT (sizeof(int) * CHAR_BIT) #define dm_bit(bs, i) \ ((bs)[((i) / DM_BITS_PER_INT) + 1] & (0x1 << ((i) & (DM_BITS_PER_INT - 1)))) #define dm_bit_set(bs, i) \ ((bs)[((i) / DM_BITS_PER_INT) + 1] |= (0x1 << ((i) & (DM_BITS_PER_INT - 1)))) #define dm_bit_clear(bs, i) \ ((bs)[((i) / DM_BITS_PER_INT) + 1] &= ~(0x1 << ((i) & (DM_BITS_PER_INT - 1)))) #define dm_bit_set_all(bs) \ memset((bs) + 1, -1, ((*(bs) / DM_BITS_PER_INT) + 1) * sizeof(int)) #define dm_bit_clear_all(bs) \ memset((bs) + 1, 0, ((*(bs) / DM_BITS_PER_INT) + 1) * sizeof(int)) #define dm_bit_copy(bs1, bs2) \ memcpy((bs1) + 1, (bs2) + 1, ((*(bs1) / DM_BITS_PER_INT) + 1) * sizeof(int)) /* Returns number of set bits */ static inline unsigned hweight32(uint32_t i) { unsigned r = (i & 0x55555555) + ((i >> 1) & 0x55555555); r = (r & 0x33333333) + ((r >> 2) & 0x33333333); r = (r & 0x0F0F0F0F) + ((r >> 4) & 0x0F0F0F0F); r = (r & 0x00FF00FF) + ((r >> 8) & 0x00FF00FF); return (r & 0x0000FFFF) + ((r >> 16) & 0x0000FFFF); } /**************** * hash functions ****************/ struct dm_hash_table; struct dm_hash_node; typedef void (*dm_hash_iterate_fn) (void *data); struct dm_hash_table *dm_hash_create(unsigned size_hint); void dm_hash_destroy(struct dm_hash_table *t); void dm_hash_wipe(struct dm_hash_table *t); void *dm_hash_lookup(struct dm_hash_table *t, const char *key); int dm_hash_insert(struct dm_hash_table *t, const char *key, void *data); void dm_hash_remove(struct dm_hash_table *t, const char *key); void *dm_hash_lookup_binary(struct dm_hash_table *t, const void *key, uint32_t len); int dm_hash_insert_binary(struct dm_hash_table *t, const void *key, uint32_t len, void *data); void dm_hash_remove_binary(struct dm_hash_table *t, const void *key, uint32_t len); unsigned dm_hash_get_num_entries(struct dm_hash_table *t); void dm_hash_iter(struct dm_hash_table *t, dm_hash_iterate_fn f); char *dm_hash_get_key(struct dm_hash_table *t, struct dm_hash_node *n); void *dm_hash_get_data(struct dm_hash_table *t, struct dm_hash_node *n); struct dm_hash_node *dm_hash_get_first(struct dm_hash_table *t); struct dm_hash_node *dm_hash_get_next(struct dm_hash_table *t, struct dm_hash_node *n); #define dm_hash_iterate(v, h) \ for (v = dm_hash_get_first((h)); v; \ v = dm_hash_get_next((h), v)) /**************** * list functions ****************/ /* * A list consists of a list head plus elements. * Each element has 'next' and 'previous' pointers. * The list head's pointers point to the first and the last element. */ struct dm_list { struct dm_list *n, *p; }; /* * Initialise a list before use. * The list head's next and previous pointers point back to itself. */ #define DM_LIST_INIT(name) struct dm_list name = { &(name), &(name) } void dm_list_init(struct dm_list *head); /* * Insert an element before 'head'. * If 'head' is the list head, this adds an element to the end of the list. */ void dm_list_add(struct dm_list *head, struct dm_list *elem); /* * Insert an element after 'head'. * If 'head' is the list head, this adds an element to the front of the list. */ void dm_list_add_h(struct dm_list *head, struct dm_list *elem); /* * Delete an element from its list. * Note that this doesn't change the element itself - it may still be safe * to follow its pointers. */ void dm_list_del(struct dm_list *elem); /* * Remove an element from existing list and insert before 'head'. */ void dm_list_move(struct dm_list *head, struct dm_list *elem); /* * Join 'head1' to the of 'head'. */ void dm_list_splice(struct dm_list *head, struct dm_list *head1); /* * Is the list empty? */ int dm_list_empty(const struct dm_list *head); /* * Is this the first element of the list? */ int dm_list_start(const struct dm_list *head, const struct dm_list *elem); /* * Is this the last element of the list? */ int dm_list_end(const struct dm_list *head, const struct dm_list *elem); /* * Return first element of the list or NULL if empty */ struct dm_list *dm_list_first(const struct dm_list *head); /* * Return last element of the list or NULL if empty */ struct dm_list *dm_list_last(const struct dm_list *head); /* * Return the previous element of the list, or NULL if we've reached the start. */ struct dm_list *dm_list_prev(const struct dm_list *head, const struct dm_list *elem); /* * Return the next element of the list, or NULL if we've reached the end. */ struct dm_list *dm_list_next(const struct dm_list *head, const struct dm_list *elem); /* * Given the address v of an instance of 'struct dm_list' called 'head' * contained in a structure of type t, return the containing structure. */ #define dm_list_struct_base(v, t, head) \ ((t *)((const char *)(v) - (const char *)&((t *) 0)->head)) /* * Given the address v of an instance of 'struct dm_list list' contained in * a structure of type t, return the containing structure. */ #define dm_list_item(v, t) dm_list_struct_base((v), t, list) /* * Given the address v of one known element e in a known structure of type t, * return another element f. */ #define dm_struct_field(v, t, e, f) \ (((t *)((uintptr_t)(v) - (uintptr_t)&((t *) 0)->e))->f) /* * Given the address v of a known element e in a known structure of type t, * return the list head 'list' */ #define dm_list_head(v, t, e) dm_struct_field(v, t, e, list) /* * Set v to each element of a list in turn. */ #define dm_list_iterate(v, head) \ for (v = (head)->n; v != head; v = v->n) /* * Set v to each element in a list in turn, starting from the element * in front of 'start'. * You can use this to 'unwind' a list_iterate and back out actions on * already-processed elements. * If 'start' is 'head' it walks the list backwards. */ #define dm_list_uniterate(v, head, start) \ for (v = (start)->p; v != head; v = v->p) /* * A safe way to walk a list and delete and free some elements along * the way. * t must be defined as a temporary variable of the same type as v. */ #define dm_list_iterate_safe(v, t, head) \ for (v = (head)->n, t = v->n; v != head; v = t, t = v->n) /* * Walk a list, setting 'v' in turn to the containing structure of each item. * The containing structure should be the same type as 'v'. * The 'struct dm_list' variable within the containing structure is 'field'. */ #define dm_list_iterate_items_gen(v, head, field) \ for (v = dm_list_struct_base((head)->n, __typeof__(*v), field); \ &v->field != (head); \ v = dm_list_struct_base(v->field.n, __typeof__(*v), field)) /* * Walk a list, setting 'v' in turn to the containing structure of each item. * The containing structure should be the same type as 'v'. * The list should be 'struct dm_list list' within the containing structure. */ #define dm_list_iterate_items(v, head) dm_list_iterate_items_gen(v, (head), list) /* * Walk a list, setting 'v' in turn to the containing structure of each item. * The containing structure should be the same type as 'v'. * The 'struct dm_list' variable within the containing structure is 'field'. * t must be defined as a temporary variable of the same type as v. */ #define dm_list_iterate_items_gen_safe(v, t, head, field) \ for (v = dm_list_struct_base((head)->n, __typeof__(*v), field), \ t = dm_list_struct_base(v->field.n, __typeof__(*v), field); \ &v->field != (head); \ v = t, t = dm_list_struct_base(v->field.n, __typeof__(*v), field)) /* * Walk a list, setting 'v' in turn to the containing structure of each item. * The containing structure should be the same type as 'v'. * The list should be 'struct dm_list list' within the containing structure. * t must be defined as a temporary variable of the same type as v. */ #define dm_list_iterate_items_safe(v, t, head) \ dm_list_iterate_items_gen_safe(v, t, (head), list) /* * Walk a list backwards, setting 'v' in turn to the containing structure * of each item. * The containing structure should be the same type as 'v'. * The 'struct dm_list' variable within the containing structure is 'field'. */ #define dm_list_iterate_back_items_gen(v, head, field) \ for (v = dm_list_struct_base((head)->p, __typeof__(*v), field); \ &v->field != (head); \ v = dm_list_struct_base(v->field.p, __typeof__(*v), field)) /* * Walk a list backwards, setting 'v' in turn to the containing structure * of each item. * The containing structure should be the same type as 'v'. * The list should be 'struct dm_list list' within the containing structure. */ #define dm_list_iterate_back_items(v, head) dm_list_iterate_back_items_gen(v, (head), list) /* * Return the number of elements in a list by walking it. */ unsigned int dm_list_size(const struct dm_list *head); /********* * selinux *********/ /* * Obtain SELinux security context assigned for the path and set this * context for creating a new file system object. This security context * is global and it is used until reset to default policy behaviour * by calling 'dm_prepare_selinux_context(NULL, 0)'. */ int dm_prepare_selinux_context(const char *path, mode_t mode); /* * Set SELinux context for existing file system object. */ int dm_set_selinux_context(const char *path, mode_t mode); /********************* * string manipulation *********************/ /* * Break up the name of a mapped device into its constituent * Volume Group, Logical Volume and Layer (if present). * If mem is supplied, the result is allocated from the mempool. * Otherwise the strings are changed in situ. */ int dm_split_lvm_name(struct dm_pool *mem, const char *dmname, char **vgname, char **lvname, char **layer); /* * Destructively split buffer into NULL-separated words in argv. * Returns number of words. */ int dm_split_words(char *buffer, unsigned max, unsigned ignore_comments, /* Not implemented */ char **argv); /* * Returns -1 if buffer too small */ int dm_snprintf(char *buf, size_t bufsize, const char *format, ...) __attribute__ ((format(printf, 3, 4))); /* * Returns pointer to the last component of the path. */ const char *dm_basename(const char *path); /************************** * file/stream manipulation **************************/ /* * Create a directory (with parent directories if necessary). * Returns 1 on success, 0 on failure. */ int dm_create_dir(const char *dir); /* * Close a stream, with nicer error checking than fclose's. * Derived from gnulib's close-stream.c. * * Close "stream". Return 0 if successful, and EOF (setting errno) * otherwise. Upon failure, set errno to 0 if the error number * cannot be determined. Useful mainly for writable streams. */ int dm_fclose(FILE *stream); /* * Returns size of a buffer which is allocated with dm_malloc. * Pointer to the buffer is stored in *buf. * Returns -1 on failure leaving buf undefined. */ int dm_asprintf(char **buf, const char *format, ...) __attribute__ ((format(printf, 2, 3))); /* * create lockfile (pidfile) - create and lock a lock file * @lockfile: location of lock file * * Returns: 1 on success, 0 otherwise, errno is handled internally */ int dm_create_lockfile(const char* lockfile); /* * Query whether a daemon is running based on its lockfile * * Returns: 1 if running, 0 if not */ int dm_daemon_is_running(const char* lockfile); /********************* * regular expressions *********************/ struct dm_regex; /* * Initialise an array of num patterns for matching. * Uses memory from mem. */ struct dm_regex *dm_regex_create(struct dm_pool *mem, const char * const *patterns, unsigned num_patterns); /* * Match string s against the patterns. * Returns the index of the highest pattern in the array that matches, * or -1 if none match. */ int dm_regex_match(struct dm_regex *regex, const char *s); /* * This is useful for regression testing only. The idea is if two * fingerprints are different, then the two dfas are certainly not * isomorphic. If two fingerprints _are_ the same then it's very likely * that the dfas are isomorphic. * * This function must be called before any matching is done. */ uint32_t dm_regex_fingerprint(struct dm_regex *regex); /********************* * reporting functions *********************/ struct dm_report_object_type { uint32_t id; /* Powers of 2 */ const char *desc; const char *prefix; /* field id string prefix (optional) */ void *(*data_fn)(void *object); /* callback from report_object() */ }; struct dm_report_field; /* * dm_report_field_type flags */ #define DM_REPORT_FIELD_MASK 0x000000FF #define DM_REPORT_FIELD_ALIGN_MASK 0x0000000F #define DM_REPORT_FIELD_ALIGN_LEFT 0x00000001 #define DM_REPORT_FIELD_ALIGN_RIGHT 0x00000002 #define DM_REPORT_FIELD_TYPE_MASK 0x000000F0 #define DM_REPORT_FIELD_TYPE_STRING 0x00000010 #define DM_REPORT_FIELD_TYPE_NUMBER 0x00000020 #define DM_REPORT_FIELD_TYPE_ID_LEN 32 #define DM_REPORT_FIELD_TYPE_HEADING_LEN 32 struct dm_report; struct dm_report_field_type { uint32_t type; /* object type id */ uint32_t flags; /* DM_REPORT_FIELD_* */ uint32_t offset; /* byte offset in the object */ int32_t width; /* default width */ /* string used to specify the field */ const char id[DM_REPORT_FIELD_TYPE_ID_LEN]; /* string printed in header */ const char heading[DM_REPORT_FIELD_TYPE_HEADING_LEN]; int (*report_fn)(struct dm_report *rh, struct dm_pool *mem, struct dm_report_field *field, const void *data, void *private_data); const char *desc; /* description of the field */ }; /* * dm_report_init output_flags */ #define DM_REPORT_OUTPUT_MASK 0x000000FF #define DM_REPORT_OUTPUT_ALIGNED 0x00000001 #define DM_REPORT_OUTPUT_BUFFERED 0x00000002 #define DM_REPORT_OUTPUT_HEADINGS 0x00000004 #define DM_REPORT_OUTPUT_FIELD_NAME_PREFIX 0x00000008 #define DM_REPORT_OUTPUT_FIELD_UNQUOTED 0x00000010 #define DM_REPORT_OUTPUT_COLUMNS_AS_ROWS 0x00000020 struct dm_report *dm_report_init(uint32_t *report_types, const struct dm_report_object_type *types, const struct dm_report_field_type *fields, const char *output_fields, const char *output_separator, uint32_t output_flags, const char *sort_keys, void *private_data); int dm_report_object(struct dm_report *rh, void *object); int dm_report_output(struct dm_report *rh); void dm_report_free(struct dm_report *rh); /* * Prefix added to each field name with DM_REPORT_OUTPUT_FIELD_NAME_PREFIX */ int dm_report_set_output_field_name_prefix(struct dm_report *rh, const char *report_prefix); /* * Report functions are provided for simple data types. * They take care of allocating copies of the data. */ int dm_report_field_string(struct dm_report *rh, struct dm_report_field *field, const char *const *data); int dm_report_field_int32(struct dm_report *rh, struct dm_report_field *field, const int32_t *data); int dm_report_field_uint32(struct dm_report *rh, struct dm_report_field *field, const uint32_t *data); int dm_report_field_int(struct dm_report *rh, struct dm_report_field *field, const int *data); int dm_report_field_uint64(struct dm_report *rh, struct dm_report_field *field, const uint64_t *data); /* * For custom fields, allocate the data in 'mem' and use * dm_report_field_set_value(). * 'sortvalue' may be NULL if it matches 'value' */ void dm_report_field_set_value(struct dm_report_field *field, const void *value, const void *sortvalue); /* Cookie prefixes. * The cookie value consists of a prefix (16 bits) and a base (16 bits). * We can use the prefix to store the flags. These flags are sent to * kernel within given dm task. When returned back to userspace in * DM_COOKIE udev environment variable, we can control several aspects * of udev rules we use by decoding the cookie prefix. When doing the * notification, we replace the cookie prefix with DM_COOKIE_MAGIC, * so we notify the right semaphore. * It is still possible to use cookies for passing the flags to udev * rules even when udev_sync is disabled. The base part of the cookie * will be zero (there's no notification semaphore) and prefix will be * set then. However, having udev_sync enabled is highly recommended. */ #define DM_COOKIE_MAGIC 0x0D4D #define DM_UDEV_FLAGS_MASK 0xFFFF0000 #define DM_UDEV_FLAGS_SHIFT 16 /* * DM_UDEV_DISABLE_DM_RULES_FLAG is set in case we need to disable * basic device-mapper udev rules that create symlinks in /dev/ * directory. However, we can't reliably prevent creating default * nodes by udev (commonly /dev/dm-X, where X is a number). */ #define DM_UDEV_DISABLE_DM_RULES_FLAG 0x0001 /* * DM_UDEV_DISABLE_SUBSYTEM_RULES_FLAG is set in case we need to disable * subsystem udev rules, but still we need the general DM udev rules to * be applied (to create the nodes and symlinks under /dev and /dev/disk). */ #define DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG 0x0002 /* * DM_UDEV_DISABLE_DISK_RULES_FLAG is set in case we need to disable * general DM rules that set symlinks in /dev/disk directory. */ #define DM_UDEV_DISABLE_DISK_RULES_FLAG 0x0004 /* * DM_UDEV_DISABLE_OTHER_RULES_FLAG is set in case we need to disable * all the other rules that are not general device-mapper nor subsystem * related (the rules belong to other software or packages). All foreign * rules should check this flag directly and they should ignore further * rule processing for such event. */ #define DM_UDEV_DISABLE_OTHER_RULES_FLAG 0x0008 /* * DM_UDEV_LOW_PRIORITY_FLAG is set in case we need to instruct the * udev rules to give low priority to the device that is currently * processed. For example, this provides a way to select which symlinks * could be overwritten by high priority ones if their names are equal. * Common situation is a name based on FS UUID while using origin and * snapshot devices. */ #define DM_UDEV_LOW_PRIORITY_FLAG 0x0010 /* * DM_UDEV_DISABLE_LIBRARY_FALLBACK is set in case we need to disable * libdevmapper's node management. We will rely on udev completely * and there will be no fallback action provided by libdevmapper if * udev does something improperly. */ #define DM_UDEV_DISABLE_LIBRARY_FALLBACK 0x0020 /* * DM_UDEV_PRIMARY_SOURCE_FLAG is automatically appended by * libdevmapper for all ioctls generating udev uevents. Once used in * udev rules, we know if this is a real "primary sourced" event or not. * We need to distinguish real events originated in libdevmapper from * any spurious events to gather all missing information (e.g. events * generated as a result of "udevadm trigger" command or as a result * of the "watch" udev rule). */ #define DM_UDEV_PRIMARY_SOURCE_FLAG 0x0040 int dm_cookie_supported(void); /* * Udev synchronisation functions. */ void dm_udev_set_sync_support(int sync_with_udev); int dm_udev_get_sync_support(void); void dm_udev_set_checking(int checking); int dm_udev_get_checking(void); /* * Default value to get new auto generated cookie created */ #define DM_COOKIE_AUTO_CREATE 0 int dm_udev_create_cookie(uint32_t *cookie); int dm_udev_complete(uint32_t cookie); int dm_udev_wait(uint32_t cookie); #define DM_DEV_DIR_UMASK 0022 #define DM_CONTROL_NODE_UMASK 0177 #ifdef __cplusplus } #endif #endif /* LIB_DEVICE_MAPPER_H */