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Ignore whitespace Rev HEAD → Rev 2536

/trunk/uspace/srv/vfs/vfs_register.c
1,5 → 1,5
/*
* Copyright (c) 2008 Jakub Jermar
* Copyright (c) 2007 Jakub Jermar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
28,17 → 28,16
 
/** @addtogroup fs
* @{
*/
*/
 
/**
* @file vfs_register.c
* @brief
* @file vfs.c
* @brief VFS_REGISTER method.
*/
 
#include <ipc/ipc.h>
#include <ipc/services.h>
#include <async.h>
#include <fibril.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
45,21 → 44,13
#include <string.h>
#include <ctype.h>
#include <bool.h>
#include <fibril_sync.h>
#include <adt/list.h>
#include <as.h>
#include <assert.h>
#include <atomic.h>
#include <futex.h>
#include <libadt/list.h>
#include "vfs.h"
 
FIBRIL_CONDVAR_INITIALIZE(fs_head_cv);
FIBRIL_MUTEX_INITIALIZE(fs_head_lock);
LIST_INITIALIZE(fs_head);
atomic_t fs_head_futex = FUTEX_INITIALIZER;
link_t fs_head;
 
atomic_t fs_handle_next = {
.count = 1
};
 
/** Verify the VFS info structure.
*
* @param info Info structure to be verified.
90,15 → 81,51
}
}
}
 
/*
* This check is not redundant. It ensures that the name is
* NULL-terminated, even if FS_NAME_MAXLEN characters are used.
* Check if the FS implements mandatory VFS operations.
*/
if (info->name[i] != '\0') {
dprintf("The name is not properly NULL-terminated.\n");
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_REGISTER)] != VFS_OP_DEFINED) {
dprintf("Operation VFS_REGISTER not defined by the client.\n");
return false;
}
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] != VFS_OP_DEFINED) {
dprintf("Operation VFS_MOUNT not defined by the client.\n");
return false;
}
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] != VFS_OP_DEFINED) {
dprintf("Operation VFS_UNMOUNT not defined by the client.\n");
return false;
}
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] != VFS_OP_DEFINED) {
dprintf("Operation VFS_LOOKUP not defined by the client.\n");
return false;
}
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_OPEN)] != VFS_OP_DEFINED) {
dprintf("Operation VFS_OPEN not defined by the client.\n");
return false;
}
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_CLOSE)] != VFS_OP_DEFINED) {
dprintf("Operation VFS_CLOSE not defined by the client.\n");
return false;
}
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_READ)] != VFS_OP_DEFINED) {
dprintf("Operation VFS_READ not defined by the client.\n");
return false;
}
/*
* Check if each operation is either not defined, defined or default.
*/
for (i = VFS_FIRST; i < VFS_LAST; i++) {
if ((info->ops[IPC_METHOD_TO_VFS_OP(i)] != VFS_OP_NULL) &&
(info->ops[IPC_METHOD_TO_VFS_OP(i)] != VFS_OP_DEFAULT) &&
(info->ops[IPC_METHOD_TO_VFS_OP(i)] != VFS_OP_DEFINED)) {
dprintf("Operation info not understood.\n");
return false;
}
}
return true;
}
 
115,19 → 142,19
size_t size;
 
dprintf("Processing VFS_REGISTER request received from %p.\n",
request->in_phone_hash);
request->in_phone_hash);
 
/*
* The first call has to be IPC_M_DATA_SEND in which we receive the
* VFS info structure from the client FS.
*/
if (!ipc_data_write_receive(&callid, &size)) {
if (!ipc_data_receive(&callid, &call, NULL, &size)) {
/*
* The client doesn't obey the same protocol as we do.
*/
dprintf("Receiving of VFS info failed.\n");
ipc_answer_0(callid, EINVAL);
ipc_answer_0(rid, EINVAL);
ipc_answer_fast(callid, EINVAL, 0, 0);
ipc_answer_fast(rid, EINVAL, 0, 0);
return;
}
143,32 → 170,31
* the info structure.
*/
dprintf("Received VFS info has bad size.\n");
ipc_answer_0(callid, EINVAL);
ipc_answer_0(rid, EINVAL);
ipc_answer_fast(callid, EINVAL, 0, 0);
ipc_answer_fast(rid, EINVAL, 0, 0);
return;
}
fs_info_t *fs_info;
 
/*
* Allocate and initialize a buffer for the fs_info structure.
*/
fs_info_t *fs_info;
fs_info = (fs_info_t *) malloc(sizeof(fs_info_t));
if (!fs_info) {
dprintf("Could not allocate memory for FS info.\n");
ipc_answer_0(callid, ENOMEM);
ipc_answer_0(rid, ENOMEM);
ipc_answer_fast(callid, ENOMEM, 0, 0);
ipc_answer_fast(rid, ENOMEM, 0, 0);
return;
}
link_initialize(&fs_info->fs_link);
fibril_mutex_initialize(&fs_info->phone_lock);
rc = ipc_data_write_finalize(callid, &fs_info->vfs_info, size);
rc = ipc_data_deliver(callid, &call, &fs_info->vfs_info, size);
if (rc != EOK) {
dprintf("Failed to deliver the VFS info into our AS, rc=%d.\n",
rc);
free(fs_info);
ipc_answer_0(callid, rc);
ipc_answer_0(rid, rc);
ipc_answer_fast(callid, rc, 0, 0);
ipc_answer_fast(rid, rc, 0, 0);
return;
}
 
176,33 → 202,44
if (!vfs_info_sane(&fs_info->vfs_info)) {
free(fs_info);
ipc_answer_0(callid, EINVAL);
ipc_answer_0(rid, EINVAL);
ipc_answer_fast(callid, EINVAL, 0, 0);
ipc_answer_fast(rid, EINVAL, 0, 0);
return;
}
fibril_mutex_lock(&fs_head_lock);
futex_down(&fs_head_futex);
 
/*
* Check for duplicit registrations.
*/
if (fs_name_to_handle(fs_info->vfs_info.name, false)) {
/*
* We already register a fs like this.
*/
dprintf("FS is already registered.\n");
fibril_mutex_unlock(&fs_head_lock);
free(fs_info);
ipc_answer_0(callid, EEXISTS);
ipc_answer_0(rid, EEXISTS);
return;
link_t *cur;
for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
fs_info_t *fi = list_get_instance(cur, fs_info_t,
fs_link);
/* TODO: replace strcmp with strncmp once we have it */
if (strcmp(fs_info->vfs_info.name, fi->vfs_info.name) == 0) {
/*
* We already register a fs like this.
*/
dprintf("FS is already registered.\n");
futex_up(&fs_head_futex);
free(fs_info);
ipc_answer_fast(callid, EEXISTS, 0, 0);
ipc_answer_fast(rid, EEXISTS, 0, 0);
return;
}
}
 
/*
* Add fs_info to the list of registered FS's.
*/
dprintf("Inserting FS into the list of registered file systems.\n");
dprintf("Adding FS into the registered list.\n");
list_append(&fs_info->fs_link, &fs_head);
 
/*
* ACK receiving a properly formatted, non-duplicit vfs_info.
*/
ipc_answer_fast(callid, EOK, 0, 0);
/*
* Now we want the client to send us the IPC_M_CONNECT_TO_ME call so
213,143 → 250,28
if (IPC_GET_METHOD(call) != IPC_M_CONNECT_TO_ME) {
dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
list_remove(&fs_info->fs_link);
fibril_mutex_unlock(&fs_head_lock);
futex_up(&fs_head_futex);
free(fs_info);
ipc_answer_0(callid, EINVAL);
ipc_answer_0(rid, EINVAL);
ipc_answer_fast(callid, EINVAL, 0, 0);
ipc_answer_fast(rid, EINVAL, 0, 0);
return;
}
fs_info->phone = IPC_GET_ARG5(call);
ipc_answer_0(callid, EOK);
fs_info->phone = IPC_GET_ARG3(call);
ipc_answer_fast(callid, EOK, 0, 0);
 
dprintf("Callback connection to FS created.\n");
 
/*
* The client will want us to send him the address space area with PLB.
*/
futex_up(&fs_head_futex);
 
if (!ipc_share_in_receive(&callid, &size)) {
dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
list_remove(&fs_info->fs_link);
fibril_mutex_unlock(&fs_head_lock);
ipc_hangup(fs_info->phone);
free(fs_info);
ipc_answer_0(callid, EINVAL);
ipc_answer_0(rid, EINVAL);
return;
}
/*
* We can only send the client address space area PLB_SIZE bytes long.
*/
if (size != PLB_SIZE) {
dprintf("Client suggests wrong size of PFB, size = %d\n", size);
list_remove(&fs_info->fs_link);
fibril_mutex_unlock(&fs_head_lock);
ipc_hangup(fs_info->phone);
free(fs_info);
ipc_answer_0(callid, EINVAL);
ipc_answer_0(rid, EINVAL);
return;
}
 
/*
* Commit to read-only sharing the PLB with the client.
*/
(void) ipc_share_in_finalize(callid, plb,
AS_AREA_READ | AS_AREA_CACHEABLE);
 
dprintf("Sharing PLB.\n");
 
/*
* That was it. The FS has been registered.
* In reply to the VFS_REGISTER request, we assign the client file
* system a global file system handle.
*/
fs_info->fs_handle = (fs_handle_t) atomic_postinc(&fs_handle_next);
ipc_answer_1(rid, EOK, (ipcarg_t) fs_info->fs_handle);
fibril_condvar_broadcast(&fs_head_cv);
fibril_mutex_unlock(&fs_head_lock);
dprintf("\"%.*s\" filesystem successfully registered, handle=%d.\n",
FS_NAME_MAXLEN, fs_info->vfs_info.name, fs_info->fs_handle);
}
ipc_answer_fast(rid, EOK, 0, 0);
dprintf("\"%s\" filesystem successfully registered.\n",
fs_info->vfs_info.name);
 
/** For a given file system handle, implement policy for allocating a phone.
*
* @param handle File system handle.
*
* @return Phone over which a multi-call request can be safely
* sent. Return 0 if no phone was found.
*/
int vfs_grab_phone(fs_handle_t handle)
{
int phone;
 
/*
* For now, we don't try to be very clever and very fast. We simply
* lookup the phone in the fs_head list and duplicate it. The duplicate
* phone will be returned to the client and the client will use it for
* communication. In the future, we should cache the connections so
* that they do not have to be reestablished over and over again.
*/
fibril_mutex_lock(&fs_head_lock);
link_t *cur;
fs_info_t *fs;
for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
fs = list_get_instance(cur, fs_info_t, fs_link);
if (fs->fs_handle == handle) {
fibril_mutex_unlock(&fs_head_lock);
fibril_mutex_lock(&fs->phone_lock);
phone = ipc_connect_me_to(fs->phone, 0, 0, 0);
fibril_mutex_unlock(&fs->phone_lock);
 
assert(phone > 0);
return phone;
}
}
fibril_mutex_unlock(&fs_head_lock);
return 0;
}
 
/** Tell VFS that the phone is not needed anymore.
*
* @param phone Phone to FS task.
*/
void vfs_release_phone(int phone)
{
/* TODO: implement connection caching */
ipc_hangup(phone);
}
 
/** Convert file system name to its handle.
*
* @param name File system name.
* @param lock If true, the function will lock and unlock the
* fs_head_lock.
*
* @return File system handle or zero if file system not found.
*/
fs_handle_t fs_name_to_handle(char *name, bool lock)
{
int handle = 0;
if (lock)
fibril_mutex_lock(&fs_head_lock);
link_t *cur;
for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
fs_info_t *fs = list_get_instance(cur, fs_info_t, fs_link);
if (str_cmp(fs->vfs_info.name, name) == 0) {
handle = fs->fs_handle;
break;
}
}
if (lock)
fibril_mutex_unlock(&fs_head_lock);
return handle;
}
 
/**
* @}
*/