OpenSolaris_b135/lib/libdevinfo/devinfo_devlink.h
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _DEVINFO_DEVLINK_H
#define _DEVINFO_DEVLINK_H
#ifdef __cplusplus
extern "C" {
#endif
#define _POSIX_PTHREAD_SEMANTICS /* For readdir_r */
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <thread.h>
#include <synch.h>
#include <libdevinfo.h>
#include <limits.h>
#include <stdlib.h>
#include <dirent.h>
#include <regex.h>
#include <errno.h>
#include <stdarg.h>
#include <sys/uio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/mman.h>
#include <sys/wait.h>
#include <door.h>
#include <signal.h>
#include <sys/statvfs.h>
struct db_link {
uint32_t attr; /* primary or secondary */
uint32_t path; /* link path */
uint32_t content; /* link content */
uint32_t sib; /* next link for same minor */
};
struct db_minor {
uint32_t name; /* minor name */
uint32_t nodetype; /* minor node type */
uint32_t sib; /* next minor for same node */
uint32_t link; /* next minor for same node */
};
struct db_node {
uint32_t path; /* node path */
uint32_t sib; /* node's sibling */
uint32_t child; /* first child for this node */
uint32_t minor; /* first minor for node */
};
typedef enum db_seg {
DB_NODE = 0,
DB_MINOR,
DB_LINK,
DB_STR,
DB_TYPES, /* Number of non-header segments */
DB_HEADER
} db_seg_t;
struct db_hdr {
uint32_t magic; /* Magic number */
uint32_t vers; /* database format version */
uint32_t root_idx; /* index for root node */
uint32_t dngl_idx; /* head of DB dangling links */
uint32_t page_sz; /* page size for mmap alignment */
uint32_t update_count; /* updates since last /dev synch up */
uint32_t nelems[DB_TYPES]; /* Number of elements of each type */
};
typedef struct cache_link {
char *path; /* link path */
char *content; /* link content */
uint_t attr; /* link attributes */
struct cache_link *hash; /* next link on same hash chain */
struct cache_link *sib; /* next link for same minor */
struct cache_minor *minor; /* minor for this link */
} cache_link_t;
typedef struct cache_minor {
char *name; /* minor name */
char *nodetype; /* minor nodetype */
struct cache_node *node; /* node for this minor */
struct cache_minor *sib; /* next minor for same node */
struct cache_link *link; /* first link pointing to minor */
} cache_minor_t;
typedef struct cache_node {
char *path; /* path */
struct cache_node *parent; /* node's parent */
struct cache_node *sib; /* node's sibling */
struct cache_node *child; /* first child for this node */
struct cache_minor *minor; /* first minor for node */
} cache_node_t;
struct cache {
uint_t flags; /* cache state */
uint_t update_count; /* updates since /dev synchronization */
uint_t hash_sz; /* number of hash chains */
cache_link_t **hash; /* hash table */
cache_node_t *root; /* root of cache tree */
cache_link_t *dngl; /* list of dangling links */
cache_minor_t *last_minor; /* last minor looked up */
};
struct db {
int db_fd; /* database file */
uint_t flags; /* database open mode */
struct db_hdr *hdr; /* DB header */
int seg_prot[DB_TYPES]; /* protection for segments */
caddr_t seg_base[DB_TYPES]; /* base address for segments */
};
struct di_devlink_handle {
char *dev_dir; /* <root-dir>/dev */
char *db_dir; /* <root-dir>/etc/dev */
uint_t flags; /* handle flags */
uint_t error; /* records errors encountered */
int lock_fd; /* lock file for updates */
struct cache cache;
struct db db;
};
typedef struct link_desc {
regex_t *regp;
const char *minor_path;
uint_t flags;
void *arg;
int (*fcn)(di_devlink_t, void *);
int retval;
} link_desc_t;
struct tnode {
void *node;
int flags;
struct di_devlink_handle *handle;
};
struct di_devlink {
char *rel_path;
char *abs_path;
char *content;
int type;
};
typedef struct recurse {
void *data;
int (*fcn)(struct di_devlink_handle *, void *, const char *);
} recurse_t;
/*
* Debug levels currently defined.
*/
typedef enum {
DBG_ERR = 1,
DBG_LCK,
DBG_INFO,
DBG_STEP,
DBG_ALL
} debug_level_t;
#define DB_MAGIC 0xBAC2ACAB
#define DB_FILE ".devlink_db"
#define DB_TMP ".devlink_db_tmp"
#define DB_LOCK ".devlink_db_lock"
#define DB_PERMS (S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR)
#define DB_LOCK_PERMS DB_PERMS
#define DB_VERSION 1
#define DB_NIL 0
#define DEV "/dev"
#define ETCDEV "/etc/dev"
#define DEVICES_SUFFIX "ices"
#define HDR_LEN sizeof (struct db_hdr)
#define AVG_CHAIN_SIZE 20 /* Average number of links per chain */
#define MIN_HASH_SIZE 1024 /* Min number of chains in hash table */
#define MAX_UPDATE_INTERVAL 5 /* Max DB writes before synching with /dev */
#define MAX_LOCK_RETRY 5 /* Max attempts at locking the update lock */
/*
* Various flags private to the implementation
*/
#define A_PRIMARY 0x0001U
#define A_SECONDARY 0x0002U
#define A_LINK_TYPES 0x0003U /* Mask */
#define A_VALID 0x0004U
#define TYPE_DB 0x0008U
#define TYPE_CACHE 0x0010U
#define CREATE_FLAG 0x0020U
#define INSERT_HEAD 0x0040U
#define INSERT_TAIL 0x0080U
#define OPEN_RDWR 0x0100U
#define OPEN_RDONLY 0x0200U
#define OPEN_FLAGS 0x0300U /* Mask */
#define UNLINK_FROM_HASH 0x0400U
#define SET_VALID_ATTR(a) ((a) |= A_VALID)
#define CLR_VALID_ATTR(a) ((a) &= ~A_VALID)
#define GET_VALID_ATTR(a) ((a) & A_VALID)
#define SET_DB_ERR(h) ((h)->error = 1)
#define DB_ERR(h) ((h)->error)
#define LOOKUP_DB(f) ((f) & TYPE_DB)
#define LOOKUP_CACHE(f) ((f) & TYPE_CACHE)
#define CREATE_ELEM(f) ((f) & CREATE_FLAG)
#define IS_RDWR(f) (((f) & OPEN_FLAGS) == OPEN_RDWR)
#define IS_RDONLY(f) (((f) & OPEN_FLAGS) == OPEN_RDONLY)
#define HDL_RDWR(h) (((h)->flags & OPEN_FLAGS) == OPEN_RDWR)
#define HDL_RDONLY(h) (((h)->flags & OPEN_FLAGS) == OPEN_RDONLY)
#define CACHE(h) (&(h)->cache)
#define CACHE_ROOT(h) (CACHE(h)->root)
#define CACHE_HASH(h, i) (CACHE(h)->hash[i])
#define CACHE_LAST(h) (CACHE(h)->last_minor)
#define CACHE_EMPTY(h) (CACHE(h)->root == NULL && CACHE(h)->dngl == NULL)
#define DB(h) (&(h)->db)
#define DB_HDR(h) (DB(h)->hdr)
#define DB_NUM(h, t) (DB_HDR(h)->nelems[t])
#define DB_SEG(h, t) (DB(h)->seg_base[t])
#define DB_SEG_PROT(h, t) (DB(h)->seg_prot[t])
#define DB_OPEN(h) (DB_HDR(h) != NULL)
#define DB_RDWR(h) ((DB(h)->flags & OPEN_FLAGS) == OPEN_RDWR)
#define DB_RDONLY(h) ((DB(h)->flags & OPEN_FLAGS) == OPEN_RDONLY)
#define DB_EMPTY(h) (DB_HDR(h)->root_idx == DB_NIL && \
DB_HDR(h)->dngl_idx == DB_NIL)
#define TYPE_NONE(f) (((f) & DI_LINK_TYPES) == 0)
#define TYPE_PRI(f) (((f) & DI_LINK_TYPES) == DI_PRIMARY_LINK)
#define TYPE_SEC(f) (((f) & DI_LINK_TYPES) == DI_SECONDARY_LINK)
#define LINK_TYPE(f) ((f) & DI_LINK_TYPES)
#define VALID_TYPE(f) (TYPE_NONE(f) || TYPE_PRI(f) || TYPE_SEC(f))
#define VALID_STR(h, i, s) ((i) + strlen(s) + 1 <= DB_HDR(h)->nelems[DB_STR])
#define VALID_INDEX(h, t, i) ((i) < DB_HDR(h)->nelems[t])
/*
* Environment variables used by DEBUG version of code.
*/
#define SKIP_DB "DEBUG_SKIP_DB"
#define SKIP_LAST_CACHE "DEBUG_SKIP_LAST_CACHE"
#define ALT_DB_DIR "DEBUG_ALT_DB_DIR"
/*
* Function prototypes
*/
static struct di_devlink_handle *handle_alloc(const char *dev_dir,
uint_t flags);
static int cache_alloc(struct di_devlink_handle *hdp);
static int open_db(struct di_devlink_handle *hdp, int flags);
static int invalid_db(struct di_devlink_handle *hdp, size_t fsize, long pg_sz);
static int read_nodes(struct di_devlink_handle *hdp, cache_node_t *pcnp,
uint32_t nidx);
static int read_minors(struct di_devlink_handle *hdp, cache_node_t *pcnp,
uint32_t nidx);
static int read_links(struct di_devlink_handle *hdp, cache_minor_t *pcmp,
uint32_t nidx);
static int init_hdr(struct di_devlink_handle *hdp, long page_sz,
uint32_t *count);
static size_t size_db(struct di_devlink_handle *hdp, long page_sz,
uint32_t *count);
static size_t seg_size(struct di_devlink_handle *hdp, int seg);
static cache_node_t *node_insert(struct di_devlink_handle *hdp,
cache_node_t *pcnp, const char *path, int insert);
static cache_minor_t *minor_insert(struct di_devlink_handle *hdp,
cache_node_t *pcnp, const char *name, const char *nodetype,
cache_minor_t **prev);
static cache_link_t *link_insert(struct di_devlink_handle *hdp,
cache_minor_t *mnp, const char *path, const char *content, uint32_t attr);
static void minor_delete(di_devlink_handle_t hdp, cache_minor_t *cmnp);
static void link_delete(di_devlink_handle_t hdp, cache_link_t *clp);
static int write_nodes(struct di_devlink_handle *hdp, struct db_node *pdnp,
cache_node_t *cnp, uint32_t *next);
static int write_minors(struct di_devlink_handle *hdp, struct db_node *pdnp,
cache_minor_t *cmnp, uint32_t *next);
static int write_links(struct di_devlink_handle *hdp, struct db_minor *pdmp,
cache_link_t *clp, uint32_t *next);
static void rm_link_from_hash(struct di_devlink_handle *hdp, cache_link_t *clp);
static uint32_t write_string(struct di_devlink_handle *hdp, const char *str,
uint32_t *next);
static int close_db(struct di_devlink_handle *hdp);
static void cache_free(struct di_devlink_handle *hdp);
static void handle_free(struct di_devlink_handle **pp);
static void resolve_dangling_links(struct di_devlink_handle *hdp);
static void subtree_free(struct di_devlink_handle *hdp, cache_node_t **pp);
static void node_free(cache_node_t **pp);
static void minor_free(struct di_devlink_handle *hdp, cache_minor_t **pp);
static void link_free(cache_link_t **pp);
static void count_node(cache_node_t *cnp, uint32_t *count);
static void count_minor(cache_minor_t *mnp, uint32_t *count);
static void count_link(cache_link_t *clp, uint32_t *count);
static void count_string(const char *str, uint32_t *count);
static int visit_node(const char *path, void *arg);
static int walk_tree(char *cur, void *arg,
int (*node_callback)(const char *path, void *arg));
static void *lookup_node(struct di_devlink_handle *hdp, char *path,
const int flags);
static cache_link_t *add_link(struct di_devlink_handle *hdp, const char *link,
const char *content, int primary);
static void *lookup_minor(struct di_devlink_handle *hdp, const char *minor_path,
const char *nodetype, const int flags);
static cache_link_t *link_hash(di_devlink_handle_t hdp, const char *link,
uint_t flags);
static void hash_insert(struct di_devlink_handle *hdp, cache_link_t *clp);
static uint_t hashfn(struct di_devlink_handle *hdp, const char *str);
static void get_db_path(struct di_devlink_handle *hdp, const char *fname,
char *buf, size_t blen);
static struct db_node *get_node(struct di_devlink_handle *hdp, uint32_t idx);
static struct db_node *set_node(struct di_devlink_handle *hdp, uint32_t idx);
static struct db_minor *get_minor(struct di_devlink_handle *hdp, uint32_t idx);
static struct db_minor *set_minor(struct di_devlink_handle *hdp, uint32_t idx);
static struct db_link *get_link(struct di_devlink_handle *hdp, uint32_t idx);
static struct db_link *set_link(struct di_devlink_handle *hdp, uint32_t idx);
static char *get_string(struct di_devlink_handle *hdp, uint32_t idx);
static char *set_string(struct di_devlink_handle *hdp, uint32_t idx);
static void *map_seg(struct di_devlink_handle *hdp, uint32_t idx, int prot,
db_seg_t seg);
static int walk_db(struct di_devlink_handle *hdp, link_desc_t *linkp);
static int walk_all_links(struct di_devlink_handle *hdp, link_desc_t *linkp);
static int walk_matching_links(struct di_devlink_handle *hdp,
link_desc_t *linkp);
static int visit_link(struct di_devlink_handle *hdp, link_desc_t *linkp,
struct di_devlink *vlp);
static void walk_cache_minor(di_devlink_handle_t hdp, const char *mpath,
link_desc_t *linkp);
static int walk_cache_links(di_devlink_handle_t hdp, cache_link_t *clp,
link_desc_t *linkp);
static void walk_all_cache(di_devlink_handle_t hdp, link_desc_t *linkp);
static int cache_dev_link(struct di_devlink_handle *hdp, void *data,
const char *link_path);
static int walk_dev(struct di_devlink_handle *hdp, link_desc_t *linkp);
static int recurse_dev(struct di_devlink_handle *hdp, recurse_t *rp);
static int do_recurse(const char *dir, struct di_devlink_handle *hdp,
recurse_t *rp, int *retp);
static int check_attr(uint32_t attr);
static int attr2type(uint32_t attr);
static int check_args(link_desc_t *linkp);
static void *get_last_node(struct di_devlink_handle *hdp, const char *path,
int flags);
static void *get_last_minor(struct di_devlink_handle *hdp,
const char *devfs_path, const char *minor_name, int flags);
static void set_last_minor(struct di_devlink_handle *hdp, cache_minor_t *cmnp,
int flags);
static int enter_db_lock(struct di_devlink_handle *hdp, const char *root_dir);
static void exit_db_lock(struct di_devlink_handle *hdp);
static char *minor_colon(const char *path);
static const char *rel_path(struct di_devlink_handle *hdp, const char *path);
static int link_flag(uint_t flags);
static int s_readlink(const char *link, char *buf, size_t blen);
static cache_minor_t *link2minor(struct di_devlink_handle *hdp,
cache_link_t *clp);
static int link_cmp(cache_link_t *clp, const char *content, int type);
static void delete_unused_nodes(di_devlink_handle_t hdp, cache_node_t *cnp);
static void delete_unused_minor(di_devlink_handle_t hdp, cache_minor_t *cmnp);
static int synchronize_db(di_devlink_handle_t hdp);
static void dprintf(debug_level_t msglevel, const char *fmt, ...);
static di_devlink_handle_t devlink_snapshot(const char *root_dir);
static int devlink_create(const char *root, const char *name, int dca_flags);
static int dca_init(const char *name, struct dca_off *dcp, int dca_flags);
static void exec_cmd(const char *root, struct dca_off *dcp);
static int do_exec(const char *path, char *const argv[]);
static int start_daemon(const char *root, int install);
static int daemon_call(const char *root, struct dca_off *dcp);
int is_minor_node(const char *contents, const char **mn_root);
char *s_realpath(const char *path, char *resolved_path);
#ifdef __cplusplus
}
#endif
#endif /* _DEVINFO_DEVLINK_H */