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  1. /*
  2.  * Copyright (c) 2008 Jakub Jermar
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup fs
  30.  * @{
  31.  */
  32.  
  33. #ifndef VFS_VFS_H_
  34. #define VFS_VFS_H_
  35.  
  36. #include <ipc/ipc.h>
  37. #include <adt/list.h>
  38. #include <fibril_sync.h>
  39. #include <sys/types.h>
  40. #include <devmap.h>
  41. #include <bool.h>
  42. #include <ipc/vfs.h>
  43.  
  44. // FIXME: according to CONFIG_DEBUG
  45. // #define dprintf(...)  printf(__VA_ARGS__)
  46.  
  47. #define dprintf(...)
  48.  
  49. /**
  50.  * A structure like this will be allocated for each registered file system.
  51.  */
  52. typedef struct {
  53.     link_t fs_link;
  54.     vfs_info_t vfs_info;
  55.     fs_handle_t fs_handle;
  56.     fibril_mutex_t phone_lock;
  57.     ipcarg_t phone;
  58. } fs_info_t;
  59.  
  60. /**
  61.  * VFS_PAIR uniquely represents a file system instance.
  62.  */
  63. #define VFS_PAIR \
  64.     fs_handle_t fs_handle; \
  65.     dev_handle_t dev_handle;
  66.  
  67. /**
  68.  * VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but
  69.  * doesn't contain any state. For a stateful structure, see vfs_node_t.
  70.  *
  71.  * @note    fs_handle, dev_handle and index are meant to be returned in one
  72.  *      IPC reply.
  73.  */
  74. #define VFS_TRIPLET \
  75.     VFS_PAIR; \
  76.     fs_index_t index;
  77.  
  78. typedef struct {
  79.     VFS_PAIR;
  80. } vfs_pair_t;
  81.  
  82. typedef struct {
  83.     VFS_TRIPLET;
  84. } vfs_triplet_t;
  85.  
  86. typedef enum vfs_node_type {
  87.     VFS_NODE_UNKNOWN,
  88.     VFS_NODE_FILE,
  89.     VFS_NODE_DIRECTORY,
  90. } vfs_node_type_t;
  91.  
  92. typedef struct {
  93.     vfs_triplet_t triplet;
  94.     vfs_node_type_t type;
  95.     size_t size;
  96.     unsigned lnkcnt;
  97. } vfs_lookup_res_t;
  98.  
  99. /**
  100.  * Instances of this type represent an active, in-memory VFS node and any state
  101.  * which may be associated with it.
  102.  */
  103. typedef struct {
  104.     VFS_TRIPLET;        /**< Identity of the node. */
  105.  
  106.     /**
  107.      * Usage counter.  This includes, but is not limited to, all vfs_file_t
  108.      * structures that reference this node.
  109.      */
  110.     unsigned refcnt;
  111.    
  112.     /** Number of names this node has in the file system namespace. */
  113.     unsigned lnkcnt;
  114.  
  115.     link_t nh_link;     /**< Node hash-table link. */
  116.  
  117.     vfs_node_type_t type;   /**< Partial info about the node type. */
  118.  
  119.     size_t size;        /**< Cached size if the node is a file. */
  120.  
  121.     /**
  122.      * Holding this rwlock prevents modifications of the node's contents.
  123.      */
  124.     fibril_rwlock_t contents_rwlock;
  125. } vfs_node_t;
  126.  
  127. /**
  128.  * Instances of this type represent an open file. If the file is opened by more
  129.  * than one task, there will be a separate structure allocated for each task.
  130.  */
  131. typedef struct {
  132.     /** Serializes access to this open file. */
  133.     fibril_mutex_t lock;
  134.  
  135.     vfs_node_t *node;
  136.    
  137.     /** Number of file handles referencing this file. */
  138.     unsigned refcnt;
  139.  
  140.     /** Append on write. */
  141.     bool append;
  142.  
  143.     /** Current position in the file. */
  144.     off_t pos;
  145. } vfs_file_t;
  146.  
  147. extern fibril_mutex_t nodes_mutex;
  148.  
  149. extern link_t fs_head;      /**< List of registered file systems. */
  150.  
  151. extern vfs_pair_t rootfs;   /**< Root file system. */
  152.  
  153. /** Each instance of this type describes one path lookup in progress. */
  154. typedef struct {
  155.     link_t  plb_link;   /**< Active PLB entries list link. */
  156.     unsigned index;     /**< Index of the first character in PLB. */
  157.     size_t len;     /**< Number of characters in this PLB entry. */
  158. } plb_entry_t;
  159.  
  160. extern fibril_mutex_t plb_mutex;/**< Mutex protecting plb and plb_head. */
  161. extern uint8_t *plb;        /**< Path Lookup Buffer */
  162. extern link_t plb_head;     /**< List of active PLB entries. */
  163.  
  164. #define MAX_MNTOPTS_LEN     256
  165.  
  166. /** Holding this rwlock prevents changes in file system namespace. */
  167. extern fibril_rwlock_t namespace_rwlock;
  168.  
  169. extern int vfs_grab_phone(fs_handle_t);
  170. extern void vfs_release_phone(int);
  171.  
  172. extern fibril_mutex_t fs_head_lock;
  173. extern bool pending_new_fs;
  174. extern fibril_condvar_t pending_cv;
  175.  
  176. extern fs_handle_t fs_name_to_handle(char *, bool);
  177.  
  178. extern int vfs_lookup_internal(char *, int, vfs_lookup_res_t *,
  179.     vfs_pair_t *, ...);
  180. extern int vfs_open_node_internal(vfs_lookup_res_t *);
  181.  
  182. extern bool vfs_nodes_init(void);
  183. extern vfs_node_t *vfs_node_get(vfs_lookup_res_t *);
  184. extern void vfs_node_put(vfs_node_t *);
  185.  
  186. #define MAX_OPEN_FILES  128
  187.  
  188. extern bool vfs_files_init(void);
  189. extern vfs_file_t *vfs_file_get(int);
  190. extern int vfs_fd_alloc(void);
  191. extern int vfs_fd_free(int);
  192.  
  193. extern void vfs_file_addref(vfs_file_t *);
  194. extern void vfs_file_delref(vfs_file_t *);
  195.  
  196. extern void vfs_node_addref(vfs_node_t *);
  197. extern void vfs_node_delref(vfs_node_t *);
  198.  
  199. extern void vfs_process_pending_mount(void);
  200. extern void vfs_register(ipc_callid_t, ipc_call_t *);
  201. extern void vfs_mount(ipc_callid_t, ipc_call_t *);
  202. extern void vfs_open(ipc_callid_t, ipc_call_t *);
  203. extern void vfs_open_node(ipc_callid_t, ipc_call_t *);
  204. extern void vfs_device(ipc_callid_t, ipc_call_t *);
  205. extern void vfs_sync(ipc_callid_t, ipc_call_t *);
  206. extern void vfs_node(ipc_callid_t, ipc_call_t *);
  207. extern void vfs_close(ipc_callid_t, ipc_call_t *);
  208. extern void vfs_read(ipc_callid_t, ipc_call_t *);
  209. extern void vfs_write(ipc_callid_t, ipc_call_t *);
  210. extern void vfs_seek(ipc_callid_t, ipc_call_t *);
  211. extern void vfs_truncate(ipc_callid_t, ipc_call_t *);
  212. extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);
  213. extern void vfs_unlink(ipc_callid_t, ipc_call_t *);
  214. extern void vfs_rename(ipc_callid_t, ipc_call_t *);
  215.  
  216. #endif
  217.  
  218. /**
  219.  * @}
  220.  */
  221.