WebSVN – HelenOS – Diff – /trunk/uspace/srv/vfs/vfs_ops.c


/*
 * Copyright (c) 2008 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/** @addtogroup fs
 * @{
 */
 
/**
 * @file vfs_ops.c
 * @brief Operations that VFS offers to its clients.
 */
 
#include "vfs.h"
#include <ipc/ipc.h>
#include <async.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <bool.h>
#include <futex.h>
#include <fibril_sync.h>
#include <adt/list.h>
#include <unistd.h>
#include <ctype.h>
#include <fcntl.h>
#include <assert.h>
#include <vfs/canonify.h>
 
/* Forward declarations of static functions. */
static int vfs_truncate_internal(fs_handle_t, dev_handle_t, fs_index_t, size_t);
 
/** Pending mount structure. */
typedef struct {
    link_t link;
    char *fs_name;            /**< File system name */
    char *mp;                 /**< Mount point */
    char *opts;       /**< Mount options. */
    ipc_callid_t callid;      /**< Call ID waiting for the mount */
    ipc_callid_t rid;         /**< Request ID */
    dev_handle_t dev_handle;  /**< Device handle */
} pending_req_t;
 
FIBRIL_CONDVAR_INITIALIZE(pending_cv);
bool pending_new_fs = false;    /**< True if a new file system was mounted. */
LIST_INITIALIZE(pending_req);
 
/**
 * This rwlock prevents the race between a triplet-to-VFS-node resolution and a
 * concurrent VFS operation which modifies the file system namespace.
 */
FIBRIL_RWLOCK_INITIALIZE(namespace_rwlock);
 
vfs_pair_t rootfs = {
    .fs_handle = 0,
    .dev_handle = 0
};
 
static void vfs_mount_internal(ipc_callid_t rid, dev_handle_t dev_handle,
    fs_handle_t fs_handle, char *mp, char *opts)
{
    vfs_lookup_res_t mp_res;
    vfs_lookup_res_t mr_res;
    vfs_node_t *mp_node = NULL;
    vfs_node_t *mr_node;
    fs_index_t rindex;
    size_t rsize;
    unsigned rlnkcnt;
    ipcarg_t rc;
    int phone;
    aid_t msg;
    ipc_call_t answer;
   
    /* Resolve the path to the mountpoint. */
    fibril_rwlock_write_lock(&namespace_rwlock);
    if (rootfs.fs_handle) {
        /* We already have the root FS. */
        if (str_cmp(mp, "/") == 0) {
            /* Trying to mount root FS over root FS */
            fibril_rwlock_write_unlock(&namespace_rwlock);
            ipc_answer_0(rid, EBUSY);
            return;
        }
       
        rc = vfs_lookup_internal(mp, L_DIRECTORY, &mp_res, NULL);
        if (rc != EOK) {
            /* The lookup failed for some reason. */
            fibril_rwlock_write_unlock(&namespace_rwlock);
            ipc_answer_0(rid, rc);
            return;
        }
       
        mp_node = vfs_node_get(&mp_res);
        if (!mp_node) {
            fibril_rwlock_write_unlock(&namespace_rwlock);
            ipc_answer_0(rid, ENOMEM);
            return;
        }
       
        /*
         * Now we hold a reference to mp_node.
         * It will be dropped upon the corresponding VFS_UNMOUNT.
         * This prevents the mount point from being deleted.
         */
    } else {
        /* We still don't have the root file system mounted. */
        if (str_cmp(mp, "/") == 0) {
            /*
             * For this simple, but important case,
             * we are almost done.
             */
           
            /* Tell the mountee that it is being mounted. */
            phone = vfs_grab_phone(fs_handle);
            msg = async_send_1(phone, VFS_MOUNTED,
                (ipcarg_t) dev_handle, &answer);
            /* send the mount options */
            rc = ipc_data_write_start(phone, (void *)opts,
                str_size(opts));
            if (rc != EOK) {
 
                async_wait_for(msg, NULL);
                vfs_release_phone(phone);
                fibril_rwlock_write_unlock(&namespace_rwlock);
                ipc_answer_0(rid, rc);
                return;
            }
 
            async_wait_for(msg, &rc);
            vfs_release_phone(phone);
           
            if (rc != EOK) {
                fibril_rwlock_write_unlock(&namespace_rwlock);
                ipc_answer_0(rid, rc);
                return;
            }
 
            rindex = (fs_index_t) IPC_GET_ARG1(answer);
            rsize = (size_t) IPC_GET_ARG2(answer);
            rlnkcnt = (unsigned) IPC_GET_ARG3(answer);
           
            mr_res.triplet.fs_handle = fs_handle;
            mr_res.triplet.dev_handle = dev_handle;
            mr_res.triplet.index = rindex;
            mr_res.size = rsize;
            mr_res.lnkcnt = rlnkcnt;
            mr_res.type = VFS_NODE_DIRECTORY;
           
            rootfs.fs_handle = fs_handle;
            rootfs.dev_handle = dev_handle;
           
            /* Add reference to the mounted root. */
            mr_node = vfs_node_get(&mr_res);
            assert(mr_node);
           
            fibril_rwlock_write_unlock(&namespace_rwlock);
            ipc_answer_0(rid, rc);
            return;
        } else {
            /*
             * We can't resolve this without the root filesystem
             * being mounted first.
             */
            fibril_rwlock_write_unlock(&namespace_rwlock);
            ipc_answer_0(rid, ENOENT);
            return;
        }
    }
   
    /*
     * At this point, we have all necessary pieces: file system and device
     * handles, and we know the mount point VFS node.
     */
   
    int mountee_phone = vfs_grab_phone(fs_handle);
    assert(mountee_phone >= 0);
 
 
    phone = vfs_grab_phone(mp_res.triplet.fs_handle);
    msg = async_send_4(phone, VFS_MOUNT,
        (ipcarg_t) mp_res.triplet.dev_handle,
        (ipcarg_t) mp_res.triplet.index,
        (ipcarg_t) fs_handle,
        (ipcarg_t) dev_handle, &answer);
   
    /* send connection */
    rc = async_req_1_0(phone, IPC_M_CONNECTION_CLONE, mountee_phone);
    if (rc != EOK) {
 
        async_wait_for(msg, NULL);
        vfs_release_phone(mountee_phone);
        vfs_release_phone(phone);
        /* Mount failed, drop reference to mp_node. */
        if (mp_node)
            vfs_node_put(mp_node);
        ipc_answer_0(rid, rc);
        fibril_rwlock_write_unlock(&namespace_rwlock);
        return;
    }
 
    vfs_release_phone(mountee_phone);
   
    /* send the mount options */
    rc = ipc_data_write_start(phone, (void *)opts, str_size(opts));
    if (rc != EOK) {
 
        async_wait_for(msg, NULL);
        vfs_release_phone(phone);
        /* Mount failed, drop reference to mp_node. */
        if (mp_node)
            vfs_node_put(mp_node);
        fibril_rwlock_write_unlock(&namespace_rwlock);
        ipc_answer_0(rid, rc);
        return;
    }
 
    async_wait_for(msg, &rc);
    vfs_release_phone(phone);
   
    if (rc == EOK) {
        rindex = (fs_index_t) IPC_GET_ARG1(answer);
        rsize = (size_t) IPC_GET_ARG2(answer);
        rlnkcnt = (unsigned) IPC_GET_ARG3(answer);
   
        mr_res.triplet.fs_handle = fs_handle;
        mr_res.triplet.dev_handle = dev_handle;
        mr_res.triplet.index = rindex;
        mr_res.size = rsize;
        mr_res.lnkcnt = rlnkcnt;
        mr_res.type = VFS_NODE_DIRECTORY;
   
        /* Add reference to the mounted root. */
        mr_node = vfs_node_get(&mr_res);
        assert(mr_node);
    } else {
        /* Mount failed, drop reference to mp_node. */
        if (mp_node)
            vfs_node_put(mp_node);
    }
 
    ipc_answer_0(rid, rc);
    fibril_rwlock_write_unlock(&namespace_rwlock);
}
 
/** Process pending mount requests */
void vfs_process_pending_mount(void)
{
    link_t *cur;
   
    while (true) {
        fibril_mutex_lock(&fs_head_lock);
        while (!pending_new_fs)
            fibril_condvar_wait(&pending_cv, &fs_head_lock);
rescan:
        for (cur = pending_req.next; cur != &pending_req;
            cur = cur->next) {
            pending_req_t *pr = list_get_instance(cur,
                pending_req_t, link);
            fs_handle_t fs_handle = fs_name_to_handle(pr->fs_name,
                false);
            if (!fs_handle)
                continue;
       
            /* Acknowledge that we know fs_name. */
            ipc_answer_0(pr->callid, EOK);
       
            list_remove(cur);
            fibril_mutex_unlock(&fs_head_lock);
           
            /* Do the mount */
            vfs_mount_internal(pr->rid, pr->dev_handle, fs_handle,
                pr->mp, pr->opts);
 
            free(pr->fs_name);
            free(pr->mp);
            free(pr->opts);
            free(pr);
       
            fibril_mutex_lock(&fs_head_lock);
            goto rescan;
        }
        pending_new_fs = false;
        fibril_mutex_unlock(&fs_head_lock);
    }
}
 
void vfs_mount(ipc_callid_t rid, ipc_call_t *request)
{
    /*
     * We expect the library to do the device-name to device-handle
     * translation for us, thus the device handle will arrive as ARG1
     * in the request.
     */
    dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
   
    /*
     * Mount flags are passed as ARG2.
     */
    unsigned int flags = (unsigned int) IPC_GET_ARG2(*request);
   
    /*
     * For now, don't make use of ARG3, but it can be used to
     * carry mount options in the future.
     */
   
    /* We want the client to send us the mount point. */
    ipc_callid_t callid;
    size_t size;
    if (!ipc_data_write_receive(&callid, &size)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
   
    /* Check whether size is reasonable wrt. the mount point. */
    if ((size < 1) || (size > MAX_PATH_LEN)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
   
    /* Allocate buffer for the mount point data being received. */
    char *mp = malloc(size + 1);
    if (!mp) {
        ipc_answer_0(callid, ENOMEM);
        ipc_answer_0(rid, ENOMEM);
        return;
    }
   
    /* Deliver the mount point. */
    ipcarg_t retval = ipc_data_write_finalize(callid, mp, size);
    if (retval != EOK) {
        ipc_answer_0(rid, retval);
        free(mp);
        return;
    }
    mp[size] = '\0';
   
    /* Now we expect to receive the mount options. */
    if (!ipc_data_write_receive(&callid, &size)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        free(mp);
        return;
    }
 
    /* Check the offered options size. */
    if (size < 0 || size > MAX_MNTOPTS_LEN) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        free(mp);
        return;
    }
 
    /* Allocate buffer for the mount options. */
    char *opts = (char *) malloc(size + 1);
    if (!opts) {
        ipc_answer_0(callid, ENOMEM);
        ipc_answer_0(rid, ENOMEM);
        free(mp);
        return;
    }
 
    /* Deliver the mount options. */
    retval = ipc_data_write_finalize(callid, opts, size);
    if (retval != EOK) {
        ipc_answer_0(rid, retval);
        free(mp);
        free(opts);
        return;
    }
    opts[size] = '\0';
   
    /*
     * Now, we expect the client to send us data with the name of the file
     * system.
     */
    if (!ipc_data_write_receive(&callid, &size)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        free(mp);
        free(opts);
        return;
    }
   
    /*
     * Don't receive more than is necessary for storing a full file system
     * name.
     */
    if ((size < 1) || (size > FS_NAME_MAXLEN)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        free(mp);
        free(opts);
        return;
    }
   
    /*
     * Allocate buffer for file system name.
     */
    char *fs_name = (char *) malloc(size + 1);
    if (fs_name == NULL) {
        ipc_answer_0(callid, ENOMEM);
        ipc_answer_0(rid, ENOMEM);
        free(mp);
        free(opts);
        return;
    }
   
    /* Deliver the file system name. */
    retval = ipc_data_write_finalize(callid, fs_name, size);
    if (retval != EOK) {
        ipc_answer_0(rid, retval);
        free(mp);
        free(opts);
        free(fs_name);
        return;
    }
    fs_name[size] = '\0';
 
    /*
     * Wait for IPC_M_PING so that we can return an error if we don't know
     * fs_name.
     */
    ipc_call_t data;
    callid = async_get_call(&data);
    if (IPC_GET_METHOD(data) != IPC_M_PING) {
        ipc_answer_0(callid, ENOTSUP);
        ipc_answer_0(rid, ENOTSUP);
        free(mp);
        free(opts);
        free(fs_name);
        return;
    }
 
    /*
     * Check if we know a file system with the same name as is in fs_name.
     * This will also give us its file system handle.
     */
    fibril_mutex_lock(&fs_head_lock);
    fs_handle_t fs_handle = fs_name_to_handle(fs_name, false);
    if (!fs_handle) {
        if (flags & IPC_FLAG_BLOCKING) {
            pending_req_t *pr;
 
            /* Blocking mount, add to pending list */
            pr = (pending_req_t *) malloc(sizeof(pending_req_t));
            if (!pr) {
                fibril_mutex_unlock(&fs_head_lock);
                ipc_answer_0(callid, ENOMEM);
                ipc_answer_0(rid, ENOMEM);
                free(mp);
                free(fs_name);
                free(opts);
                return;
            }
           
            pr->fs_name = fs_name;
            pr->mp = mp;
            pr->opts = opts;
            pr->callid = callid;
            pr->rid = rid;
            pr->dev_handle = dev_handle;
            link_initialize(&pr->link);
            list_append(&pr->link, &pending_req);
            fibril_mutex_unlock(&fs_head_lock);
            return;
        }
       
        fibril_mutex_unlock(&fs_head_lock);
        ipc_answer_0(callid, ENOENT);
        ipc_answer_0(rid, ENOENT);
        free(mp);
        free(fs_name);
        free(opts);
        return;
    }
    fibril_mutex_unlock(&fs_head_lock);
   
    /* Acknowledge that we know fs_name. */
    ipc_answer_0(callid, EOK);
   
    /* Do the mount */
    vfs_mount_internal(rid, dev_handle, fs_handle, mp, opts);
    free(mp);
    free(fs_name);
    free(opts);
}
 
void vfs_open(ipc_callid_t rid, ipc_call_t *request)
{
    if (!vfs_files_init()) {
        ipc_answer_0(rid, ENOMEM);
        return;
    }
   
    /*
     * The POSIX interface is open(path, oflag, mode).
     * We can receive oflags and mode along with the VFS_OPEN call; the path
     * will need to arrive in another call.
     *
     * We also receive one private, non-POSIX set of flags called lflag
     * used to pass information to vfs_lookup_internal().
     */
    int lflag = IPC_GET_ARG1(*request);
    int oflag = IPC_GET_ARG2(*request);
    int mode = IPC_GET_ARG3(*request);
    size_t len;
   
    /*
     * Make sure that we are called with exactly one of L_FILE and
     * L_DIRECTORY. Make sure that the user does not pass L_OPEN.
     */
    if (((lflag & (L_FILE | L_DIRECTORY)) == 0) ||
        ((lflag & (L_FILE | L_DIRECTORY)) == (L_FILE | L_DIRECTORY)) ||
        ((lflag & L_OPEN) != 0)) {
        ipc_answer_0(rid, EINVAL);
        return;
    }
   
    if (oflag & O_CREAT)
        lflag |= L_CREATE;
    if (oflag & O_EXCL)
        lflag |= L_EXCLUSIVE;
   
    ipc_callid_t callid;
    if (!ipc_data_write_receive(&callid, &len)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
   
    char *path = malloc(len + 1);
    if (!path) {
        ipc_answer_0(callid, ENOMEM);
        ipc_answer_0(rid, ENOMEM);
        return;
    }
   
    int rc;
    if ((rc = ipc_data_write_finalize(callid, path, len))) {
        ipc_answer_0(rid, rc);
        free(path);
        return;
    }
    path[len] = '\0';
   
    /*
     * Avoid the race condition in which the file can be deleted before we
     * find/create-and-lock the VFS node corresponding to the looked-up
     * triplet.
     */
    if (lflag & L_CREATE)
        fibril_rwlock_write_lock(&namespace_rwlock);
    else
        fibril_rwlock_read_lock(&namespace_rwlock);
   
    /* The path is now populated and we can call vfs_lookup_internal(). */
    vfs_lookup_res_t lr;
    rc = vfs_lookup_internal(path, lflag | L_OPEN, &lr, NULL);
    if (rc != EOK) {
        if (lflag & L_CREATE)
            fibril_rwlock_write_unlock(&namespace_rwlock);
        else
            fibril_rwlock_read_unlock(&namespace_rwlock);
        ipc_answer_0(rid, rc);
        free(path);
        return;
    }
   
    /* Path is no longer needed. */
    free(path);
   
    vfs_node_t *node = vfs_node_get(&lr);
    if (lflag & L_CREATE)
        fibril_rwlock_write_unlock(&namespace_rwlock);
    else
        fibril_rwlock_read_unlock(&namespace_rwlock);
   
    /* Truncate the file if requested and if necessary. */
    if (oflag & O_TRUNC) {
        fibril_rwlock_write_lock(&node->contents_rwlock);
        if (node->size) {
            rc = vfs_truncate_internal(node->fs_handle,
                node->dev_handle, node->index, 0);
            if (rc) {
                fibril_rwlock_write_unlock(&node->contents_rwlock);
                vfs_node_put(node);
                ipc_answer_0(rid, rc);
                return;
            }
            node->size = 0;
        }
        fibril_rwlock_write_unlock(&node->contents_rwlock);
    }
   
    /*
     * Get ourselves a file descriptor and the corresponding vfs_file_t
     * structure.
     */
    int fd = vfs_fd_alloc();
    if (fd < 0) {
        vfs_node_put(node);
        ipc_answer_0(rid, fd);
        return;
    }
    vfs_file_t *file = vfs_file_get(fd);
    file->node = node;
    if (oflag & O_APPEND)
        file->append = true;
   
    /*
     * The following increase in reference count is for the fact that the
     * file is being opened and that a file structure is pointing to it.
     * It is necessary so that the file will not disappear when
     * vfs_node_put() is called. The reference will be dropped by the
     * respective VFS_CLOSE.
     */
    vfs_node_addref(node);
    vfs_node_put(node);
   
    /* Success! Return the new file descriptor to the client. */
    ipc_answer_1(rid, EOK, fd);
}
 
void vfs_open_node(ipc_callid_t rid, ipc_call_t *request)
{
    // FIXME: check for sanity of the supplied fs, dev and index
   
    if (!vfs_files_init()) {
        ipc_answer_0(rid, ENOMEM);
        return;
    }
   
    /*
     * The interface is open_node(fs, dev, index, oflag).
     */
    vfs_lookup_res_t lr;
   
    lr.triplet.fs_handle = IPC_GET_ARG1(*request);
    lr.triplet.dev_handle = IPC_GET_ARG2(*request);
    lr.triplet.index = IPC_GET_ARG3(*request);
    int oflag = IPC_GET_ARG4(*request);
   
    fibril_rwlock_read_lock(&namespace_rwlock);
   
    int rc = vfs_open_node_internal(&lr);
    if (rc != EOK) {
        fibril_rwlock_read_unlock(&namespace_rwlock);
        ipc_answer_0(rid, rc);
        return;
    }
   
    vfs_node_t *node = vfs_node_get(&lr);
    fibril_rwlock_read_unlock(&namespace_rwlock);
   
    /* Truncate the file if requested and if necessary. */
    if (oflag & O_TRUNC) {
        fibril_rwlock_write_lock(&node->contents_rwlock);
        if (node->size) {
            rc = vfs_truncate_internal(node->fs_handle,
                node->dev_handle, node->index, 0);
            if (rc) {
                fibril_rwlock_write_unlock(&node->contents_rwlock);
                vfs_node_put(node);
                ipc_answer_0(rid, rc);
                return;
            }
            node->size = 0;
        }
        fibril_rwlock_write_unlock(&node->contents_rwlock);
    }
   
    /*
     * Get ourselves a file descriptor and the corresponding vfs_file_t
     * structure.
     */
    int fd = vfs_fd_alloc();
    if (fd < 0) {
        vfs_node_put(node);
        ipc_answer_0(rid, fd);
        return;
    }
    vfs_file_t *file = vfs_file_get(fd);
    file->node = node;
    if (oflag & O_APPEND)
        file->append = true;
   
    /*
     * The following increase in reference count is for the fact that the
     * file is being opened and that a file structure is pointing to it.
     * It is necessary so that the file will not disappear when
     * vfs_node_put() is called. The reference will be dropped by the
     * respective VFS_CLOSE.
     */
    vfs_node_addref(node);
    vfs_node_put(node);
   
    /* Success! Return the new file descriptor to the client. */
    ipc_answer_1(rid, EOK, fd);
}
 
void vfs_node(ipc_callid_t rid, ipc_call_t *request)
{
    int fd = IPC_GET_ARG1(*request);
   
    /* Lookup the file structure corresponding to the file descriptor. */
    vfs_file_t *file = vfs_file_get(fd);
    if (!file) {
        ipc_answer_0(rid, ENOENT);
        return;
    }
   
    ipc_answer_3(rid, EOK, file->node->fs_handle, file->node->dev_handle,
        file->node->index);
}
 
void vfs_device(ipc_callid_t rid, ipc_call_t *request)
{
    int fd = IPC_GET_ARG1(*request);
   
    /* Lookup the file structure corresponding to the file descriptor. */
    vfs_file_t *file = vfs_file_get(fd);
    if (!file) {
        ipc_answer_0(rid, ENOENT);
        return;
    }
   
    /*
     * Lock the open file structure so that no other thread can manipulate
     * the same open file at a time.
     */
    fibril_mutex_lock(&file->lock);
    int fs_phone = vfs_grab_phone(file->node->fs_handle);
   
    /* Make a VFS_DEVICE request at the destination FS server. */
    aid_t msg;
    ipc_call_t answer;
    msg = async_send_2(fs_phone, IPC_GET_METHOD(*request),
        file->node->dev_handle, file->node->index, &answer);
 
 
 
    /* Wait for reply from the FS server. */
    ipcarg_t rc;
    async_wait_for(msg, &rc);
 
    vfs_release_phone(fs_phone);
    fibril_mutex_unlock(&file->lock);
   
    ipc_answer_1(rid, EOK, IPC_GET_ARG1(answer));
}
 
void vfs_sync(ipc_callid_t rid, ipc_call_t *request)
{
    int fd = IPC_GET_ARG1(*request);
   
    /* Lookup the file structure corresponding to the file descriptor. */
    vfs_file_t *file = vfs_file_get(fd);
    if (!file) {
        ipc_answer_0(rid, ENOENT);
        return;
    }
   
    /*
     * Lock the open file structure so that no other thread can manipulate
     * the same open file at a time.
     */
    fibril_mutex_lock(&file->lock);
    int fs_phone = vfs_grab_phone(file->node->fs_handle);
   
    /* Make a VFS_SYMC request at the destination FS server. */
    aid_t msg;
    ipc_call_t answer;
    msg = async_send_2(fs_phone, IPC_GET_METHOD(*request),
        file->node->dev_handle, file->node->index, &answer);
 
 
 
    /* Wait for reply from the FS server. */
    ipcarg_t rc;
    async_wait_for(msg, &rc);
   
    vfs_release_phone(fs_phone);
    fibril_mutex_unlock(&file->lock);
   
    ipc_answer_0(rid, rc);
}
 
void vfs_close(ipc_callid_t rid, ipc_call_t *request)
{
    int fd = IPC_GET_ARG1(*request);
   
    /* Lookup the file structure corresponding to the file descriptor. */
    vfs_file_t *file = vfs_file_get(fd);
    if (!file) {
        ipc_answer_0(rid, ENOENT);
        return;
    }
   
    /*
     * Lock the open file structure so that no other thread can manipulate
     * the same open file at a time.
     */
    fibril_mutex_lock(&file->lock);
 
    int fs_phone = vfs_grab_phone(file->node->fs_handle);
   
    /* Make a VFS_CLOSE request at the destination FS server. */
    aid_t msg;
    ipc_call_t answer;
    msg = async_send_2(fs_phone, IPC_GET_METHOD(*request),
        file->node->dev_handle, file->node->index, &answer);
 
 
 
    /* Wait for reply from the FS server. */
    ipcarg_t rc;
    async_wait_for(msg, &rc);
 
    vfs_release_phone(fs_phone);
    fibril_mutex_unlock(&file->lock);
   
    int retval = IPC_GET_ARG1(answer);
    if (retval != EOK)
        ipc_answer_0(rid, retval);
   
    retval = vfs_fd_free(fd);
    ipc_answer_0(rid, retval);
}
 
static void vfs_rdwr(ipc_callid_t rid, ipc_call_t *request, bool read)
{
 
    /*
     * The following code strongly depends on the fact that the files data
     * structure can be only accessed by a single fibril and all file
     * operations are serialized (i.e. the reads and writes cannot
     * interleave and a file cannot be closed while it is being read).
     *
     * Additional synchronization needs to be added once the table of
     * open files supports parallel access!
     */
 
    int fd = IPC_GET_ARG1(*request);
   
    /* Lookup the file structure corresponding to the file descriptor. */
    vfs_file_t *file = vfs_file_get(fd);
    if (!file) {
        ipc_answer_0(rid, ENOENT);
        return;
    }
   
    /*
     * Now we need to receive a call with client's
     * IPC_M_DATA_READ/IPC_M_DATA_WRITE request.
     */
    ipc_callid_t callid;
    int res;
    if (read)
        res = ipc_data_read_receive(&callid, NULL);
    else
        res = ipc_data_write_receive(&callid, NULL);
    if (!res) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
   
    /*
     * Lock the open file structure so that no other thread can manipulate
     * the same open file at a time.
     */
    fibril_mutex_lock(&file->lock);
 
    /*
     * Lock the file's node so that no other client can read/write to it at
     * the same time.
     */
    if (read)
        fibril_rwlock_read_lock(&file->node->contents_rwlock);
    else
        fibril_rwlock_write_lock(&file->node->contents_rwlock);
 
    if (file->node->type == VFS_NODE_DIRECTORY) {
        /*
         * Make sure that no one is modifying the namespace
         * while we are in readdir().
         */
        assert(read);
        fibril_rwlock_read_lock(&namespace_rwlock);
    }
   
    int fs_phone = vfs_grab_phone(file->node->fs_handle);  
   
    /* Make a VFS_READ/VFS_WRITE request at the destination FS server. */
    aid_t msg;
    ipc_call_t answer;
    if (!read && file->append)
        file->pos = file->node->size;
    msg = async_send_3(fs_phone, IPC_GET_METHOD(*request),
        file->node->dev_handle, file->node->index, file->pos, &answer);
   
    /*
     * Forward the IPC_M_DATA_READ/IPC_M_DATA_WRITE request to the
     * destination FS server. The call will be routed as if sent by
     * ourselves. Note that call arguments are immutable in this case so we
     * don't have to bother.
     */
    ipc_forward_fast(callid, fs_phone, 0, 0, 0, IPC_FF_ROUTE_FROM_ME);
 
 
 
    /* Wait for reply from the FS server. */
    ipcarg_t rc;
    async_wait_for(msg, &rc);
   
    vfs_release_phone(fs_phone);
   
    size_t bytes = IPC_GET_ARG1(answer);
 
    if (file->node->type == VFS_NODE_DIRECTORY)
        fibril_rwlock_read_unlock(&namespace_rwlock);
   
    /* Unlock the VFS node. */
    if (read)
        fibril_rwlock_read_unlock(&file->node->contents_rwlock);
    else {
        /* Update the cached version of node's size. */
        if (rc == EOK)
            file->node->size = IPC_GET_ARG2(answer);
        fibril_rwlock_write_unlock(&file->node->contents_rwlock);
    }
   
    /* Update the position pointer and unlock the open file. */
    if (rc == EOK)
        file->pos += bytes;
    fibril_mutex_unlock(&file->lock);
   
    /*
     * FS server's reply is the final result of the whole operation we
     * return to the client.
     */
    ipc_answer_1(rid, rc, bytes);
}
 
void vfs_read(ipc_callid_t rid, ipc_call_t *request)
{
    vfs_rdwr(rid, request, true);
}
 
void vfs_write(ipc_callid_t rid, ipc_call_t *request)
{
    vfs_rdwr(rid, request, false);
}
 
void vfs_seek(ipc_callid_t rid, ipc_call_t *request)
{
    int fd = (int) IPC_GET_ARG1(*request);
    off_t off = (off_t) IPC_GET_ARG2(*request);
    int whence = (int) IPC_GET_ARG3(*request);
 
 
    /* Lookup the file structure corresponding to the file descriptor. */
    vfs_file_t *file = vfs_file_get(fd);
    if (!file) {
        ipc_answer_0(rid, ENOENT);
        return;
    }
 
    off_t newpos;
    fibril_mutex_lock(&file->lock);
    if (whence == SEEK_SET) {
        file->pos = off;
        fibril_mutex_unlock(&file->lock);
        ipc_answer_1(rid, EOK, off);
        return;
    }
    if (whence == SEEK_CUR) {
        if (file->pos + off < file->pos) {
            fibril_mutex_unlock(&file->lock);
            ipc_answer_0(rid, EOVERFLOW);
            return;
        }
        file->pos += off;
        newpos = file->pos;
        fibril_mutex_unlock(&file->lock);
        ipc_answer_1(rid, EOK, newpos);
        return;
    }
    if (whence == SEEK_END) {
        fibril_rwlock_read_lock(&file->node->contents_rwlock);
        size_t size = file->node->size;
        fibril_rwlock_read_unlock(&file->node->contents_rwlock);
        if (size + off < size) {
            fibril_mutex_unlock(&file->lock);
            ipc_answer_0(rid, EOVERFLOW);
            return;
        }
        newpos = size + off;
        fibril_mutex_unlock(&file->lock);
        ipc_answer_1(rid, EOK, newpos);
        return;
    }
    fibril_mutex_unlock(&file->lock);
    ipc_answer_0(rid, EINVAL);
}
 
int
vfs_truncate_internal(fs_handle_t fs_handle, dev_handle_t dev_handle,
    fs_index_t index, size_t size)
{
    ipcarg_t rc;
    int fs_phone;
   
    fs_phone = vfs_grab_phone(fs_handle);
    rc = async_req_3_0(fs_phone, VFS_TRUNCATE, (ipcarg_t)dev_handle,
        (ipcarg_t)index, (ipcarg_t)size);
    vfs_release_phone(fs_phone);
    return (int)rc;
}
 
void vfs_truncate(ipc_callid_t rid, ipc_call_t *request)
{
    int fd = IPC_GET_ARG1(*request);
    size_t size = IPC_GET_ARG2(*request);
    int rc;
 
    vfs_file_t *file = vfs_file_get(fd);
    if (!file) {
        ipc_answer_0(rid, ENOENT);
        return;
    }
    fibril_mutex_lock(&file->lock);
 
    fibril_rwlock_write_lock(&file->node->contents_rwlock);
    rc = vfs_truncate_internal(file->node->fs_handle,
        file->node->dev_handle, file->node->index, size);
    if (rc == EOK)
        file->node->size = size;
    fibril_rwlock_write_unlock(&file->node->contents_rwlock);
 
    fibril_mutex_unlock(&file->lock);
    ipc_answer_0(rid, (ipcarg_t)rc);
}
 
void vfs_mkdir(ipc_callid_t rid, ipc_call_t *request)
{
    int mode = IPC_GET_ARG1(*request);
 
    size_t len;
    ipc_callid_t callid;
 
    if (!ipc_data_write_receive(&callid, &len)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
    char *path = malloc(len + 1);
    if (!path) {
        ipc_answer_0(callid, ENOMEM);
        ipc_answer_0(rid, ENOMEM);
        return;
    }
    int rc;
    if ((rc = ipc_data_write_finalize(callid, path, len))) {
        ipc_answer_0(rid, rc);
        free(path);
        return;
    }
    path[len] = '\0';
   
    fibril_rwlock_write_lock(&namespace_rwlock);
    int lflag = L_DIRECTORY | L_CREATE | L_EXCLUSIVE;
    rc = vfs_lookup_internal(path, lflag, NULL, NULL);
    fibril_rwlock_write_unlock(&namespace_rwlock);
    free(path);
    ipc_answer_0(rid, rc);
}
 
void vfs_unlink(ipc_callid_t rid, ipc_call_t *request)
{
    int lflag = IPC_GET_ARG1(*request);
 
    size_t len;
    ipc_callid_t callid;
 
    if (!ipc_data_write_receive(&callid, &len)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
    char *path = malloc(len + 1);
    if (!path) {
        ipc_answer_0(callid, ENOMEM);
        ipc_answer_0(rid, ENOMEM);
        return;
    }
    int rc;
    if ((rc = ipc_data_write_finalize(callid, path, len))) {
        ipc_answer_0(rid, rc);
        free(path);
        return;
    }
    path[len] = '\0';
   
    fibril_rwlock_write_lock(&namespace_rwlock);
    lflag &= L_DIRECTORY;   /* sanitize lflag */
    vfs_lookup_res_t lr;
    rc = vfs_lookup_internal(path, lflag | L_UNLINK, &lr, NULL);
    free(path);
    if (rc != EOK) {
        fibril_rwlock_write_unlock(&namespace_rwlock);
        ipc_answer_0(rid, rc);
        return;
    }
 
    /*
     * The name has already been unlinked by vfs_lookup_internal().
     * We have to get and put the VFS node to ensure that it is
     * VFS_DESTROY'ed after the last reference to it is dropped.
     */
    vfs_node_t *node = vfs_node_get(&lr);
    futex_down(&nodes_futex);
    node->lnkcnt--;
    futex_up(&nodes_futex);
    fibril_rwlock_write_unlock(&namespace_rwlock);
    vfs_node_put(node);
    ipc_answer_0(rid, EOK);
}
 
void vfs_rename(ipc_callid_t rid, ipc_call_t *request)
{
    size_t olen, nlen;
    ipc_callid_t callid;
    int rc;
 
    /* Retrieve the old path. */
    if (!ipc_data_write_receive(&callid, &olen)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
    char *old = malloc(olen + 1);
    if (!old) {
        ipc_answer_0(callid, ENOMEM);
        ipc_answer_0(rid, ENOMEM);
        return;
    }
    if ((rc = ipc_data_write_finalize(callid, old, olen))) {
        ipc_answer_0(rid, rc);
        free(old);
        return;
    }
    old[olen] = '\0';
   
    /* Retrieve the new path. */
    if (!ipc_data_write_receive(&callid, &nlen)) {
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        free(old);
        return;
    }
    char *new = malloc(nlen + 1);
    if (!new) {
        ipc_answer_0(callid, ENOMEM);
        ipc_answer_0(rid, ENOMEM);
        free(old);
        return;
    }
    if ((rc = ipc_data_write_finalize(callid, new, nlen))) {
        ipc_answer_0(rid, rc);
        free(old);
        free(new);
        return;
    }
    new[nlen] = '\0';
 
    char *oldc = canonify(old, &olen);
    char *newc = canonify(new, &nlen);
    if (!oldc || !newc) {
        ipc_answer_0(rid, EINVAL);
        free(old);
        free(new);
        return;
    }
    oldc[olen] = '\0';
    newc[nlen] = '\0';
    if ((!str_lcmp(newc, oldc, str_length(oldc))) &&
        ((newc[str_length(oldc)] == '/') ||
        (str_length(oldc) == 1) ||
        (str_length(oldc) == str_length(newc)))) {
            /*
         * oldc is a prefix of newc and either
         * - newc continues with a / where oldc ends, or
         * - oldc was / itself, or
         * - oldc and newc are equal.
         */
        ipc_answer_0(rid, EINVAL);
        free(old);
        free(new);
        return;
    }
   
    vfs_lookup_res_t old_lr;
    vfs_lookup_res_t new_lr;
    vfs_lookup_res_t new_par_lr;
    fibril_rwlock_write_lock(&namespace_rwlock);
    /* Lookup the node belonging to the old file name. */
    rc = vfs_lookup_internal(oldc, L_NONE, &old_lr, NULL);
    if (rc != EOK) {
        fibril_rwlock_write_unlock(&namespace_rwlock);
        ipc_answer_0(rid, rc);
        free(old);
        free(new);
        return;
    }
    vfs_node_t *old_node = vfs_node_get(&old_lr);
    if (!old_node) {
        fibril_rwlock_write_unlock(&namespace_rwlock);
        ipc_answer_0(rid, ENOMEM);
        free(old);
        free(new);
        return;
    }
    /* Determine the path to the parent of the node with the new name. */
    char *parentc = str_dup(newc);
    if (!parentc) {
        fibril_rwlock_write_unlock(&namespace_rwlock);
        ipc_answer_0(rid, rc);
        free(old);
        free(new);
        return;
    }
    char *lastsl = str_rchr(parentc + 1, '/');
    if (lastsl)
        *lastsl = '\0';
    else
        parentc[1] = '\0';
    /* Lookup parent of the new file name. */
    rc = vfs_lookup_internal(parentc, L_NONE, &new_par_lr, NULL);
    free(parentc);  /* not needed anymore */
    if (rc != EOK) {
        fibril_rwlock_write_unlock(&namespace_rwlock);
        ipc_answer_0(rid, rc);
        free(old);
        free(new);
        return;
    }
    /* Check whether linking to the same file system instance. */
    if ((old_node->fs_handle != new_par_lr.triplet.fs_handle) ||
        (old_node->dev_handle != new_par_lr.triplet.dev_handle)) {
        fibril_rwlock_write_unlock(&namespace_rwlock);
        ipc_answer_0(rid, EXDEV);   /* different file systems */
        free(old);
        free(new);
        return;
    }
    /* Destroy the old link for the new name. */
    vfs_node_t *new_node = NULL;
    rc = vfs_lookup_internal(newc, L_UNLINK, &new_lr, NULL);
    switch (rc) {
    case ENOENT:
        /* simply not in our way */
        break;
    case EOK:
        new_node = vfs_node_get(&new_lr);
        if (!new_node) {
            fibril_rwlock_write_unlock(&namespace_rwlock);
            ipc_answer_0(rid, ENOMEM);
            free(old);
            free(new);
            return;
        }
        futex_down(&nodes_futex);
        new_node->lnkcnt--;
        futex_up(&nodes_futex);
        break;
    default:
        fibril_rwlock_write_unlock(&namespace_rwlock);
        ipc_answer_0(rid, ENOTEMPTY);
        free(old);
        free(new);
        return;
    }
    /* Create the new link for the new name. */
    rc = vfs_lookup_internal(newc, L_LINK, NULL, NULL, old_node->index);
    if (rc != EOK) {
        fibril_rwlock_write_unlock(&namespace_rwlock);
        if (new_node)
            vfs_node_put(new_node);
        ipc_answer_0(rid, rc);
        free(old);
        free(new);
        return;
    }
    futex_down(&nodes_futex);
    old_node->lnkcnt++;
    futex_up(&nodes_futex);
    /* Destroy the link for the old name. */
    rc = vfs_lookup_internal(oldc, L_UNLINK, NULL, NULL);
    if (rc != EOK) {
        fibril_rwlock_write_unlock(&namespace_rwlock);
        vfs_node_put(old_node);
        if (new_node)
            vfs_node_put(new_node);
        ipc_answer_0(rid, rc);
        free(old);
        free(new);
        return;
    }
    futex_down(&nodes_futex);
    old_node->lnkcnt--;
    futex_up(&nodes_futex);
    fibril_rwlock_write_unlock(&namespace_rwlock);
    vfs_node_put(old_node);
    if (new_node)
        vfs_node_put(new_node);
    free(old);
    free(new);
    ipc_answer_0(rid, EOK);
}
 
/**
 * @}
 */
 

Rev 4539	Rev 4551
1	/*	1	/*
2	* Copyright (c) 2008 Jakub Jermar	2	* Copyright (c) 2008 Jakub Jermar
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	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	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.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	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	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	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	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	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	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.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/** @addtogroup fs	29	/** @addtogroup fs
30	* @{	30	* @{
31	*/	31	*/
32		32
33	/**	33	/**
34	* @file vfs_ops.c	34	* @file vfs_ops.c
35	* @brief Operations that VFS offers to its clients.	35	* @brief Operations that VFS offers to its clients.
36	*/	36	*/
37		37
38	#include "vfs.h"	38	#include "vfs.h"
39	#include <ipc/ipc.h>	39	#include <ipc/ipc.h>
40	#include <async.h>	40	#include <async.h>
41	#include <errno.h>	41	#include <errno.h>
42	#include <stdio.h>	42	#include <stdio.h>
43	#include <stdlib.h>	43	#include <stdlib.h>
44	#include <string.h>	44	#include <string.h>
45	#include <bool.h>	45	#include <bool.h>
46	#include <futex.h>	46	#include <futex.h>
47	#include <fibril_sync.h>	47	#include <fibril_sync.h>
48	#include <adt/list.h>	48	#include <adt/list.h>
49	#include <unistd.h>	49	#include <unistd.h>
50	#include <ctype.h>	50	#include <ctype.h>
51	#include <fcntl.h>	51	#include <fcntl.h>
52	#include <assert.h>	52	#include <assert.h>
53	#include <vfs/canonify.h>	53	#include <vfs/canonify.h>
54		54
55	/* Forward declarations of static functions. */	55	/* Forward declarations of static functions. */
56	static int vfs_truncate_internal(fs_handle_t, dev_handle_t, fs_index_t, size_t);	56	static int vfs_truncate_internal(fs_handle_t, dev_handle_t, fs_index_t, size_t);
57		57
58	/** Pending mount structure. */	58	/** Pending mount structure. */
59	typedef struct {	59	typedef struct {
60	link_t link;	60	link_t link;
61	char fs_name; /< File system name /	61	char fs_name; /< File system name /
62	char mp; /< Mount point /	62	char mp; /< Mount point /
63	char opts; /< Mount options. /	63	char opts; /< Mount options. /
64	ipc_callid_t callid; /*< Call ID waiting for the mount /	64	ipc_callid_t callid; /*< Call ID waiting for the mount /
65	ipc_callid_t rid; /*< Request ID /	65	ipc_callid_t rid; /*< Request ID /
66	dev_handle_t dev_handle; /*< Device handle /	66	dev_handle_t dev_handle; /*< Device handle /
67	} pending_req_t;	67	} pending_req_t;
68		68
69	FIBRIL_CONDVAR_INITIALIZE(pending_cv);	69	FIBRIL_CONDVAR_INITIALIZE(pending_cv);
70	bool pending_new_fs = false; /*< True if a new file system was mounted. /	70	bool pending_new_fs = false; /*< True if a new file system was mounted. /
71	LIST_INITIALIZE(pending_req);	71	LIST_INITIALIZE(pending_req);
72		72
73	/**	73	/**
74	* This rwlock prevents the race between a triplet-to-VFS-node resolution and a	74	* This rwlock prevents the race between a triplet-to-VFS-node resolution and a
75	* concurrent VFS operation which modifies the file system namespace.	75	* concurrent VFS operation which modifies the file system namespace.
76	*/	76	*/
77	FIBRIL_RWLOCK_INITIALIZE(namespace_rwlock);	77	FIBRIL_RWLOCK_INITIALIZE(namespace_rwlock);
78		78
79	vfs_pair_t rootfs = {	79	vfs_pair_t rootfs = {
80	.fs_handle = 0,	80	.fs_handle = 0,
81	.dev_handle = 0	81	.dev_handle = 0
82	};	82	};
83		83
84	static void vfs_mount_internal(ipc_callid_t rid, dev_handle_t dev_handle,	84	static void vfs_mount_internal(ipc_callid_t rid, dev_handle_t dev_handle,
85	fs_handle_t fs_handle, char mp, char opts)	85	fs_handle_t fs_handle, char mp, char opts)
86	{	86	{
87	vfs_lookup_res_t mp_res;	87	vfs_lookup_res_t mp_res;
88	vfs_lookup_res_t mr_res;	88	vfs_lookup_res_t mr_res;
89	vfs_node_t *mp_node = NULL;	89	vfs_node_t *mp_node = NULL;
90	vfs_node_t *mr_node;	90	vfs_node_t *mr_node;
91	fs_index_t rindex;	91	fs_index_t rindex;
92	size_t rsize;	92	size_t rsize;
93	unsigned rlnkcnt;	93	unsigned rlnkcnt;
94	ipcarg_t rc;	94	ipcarg_t rc;
95	int phone;	95	int phone;
96	aid_t msg;	96	aid_t msg;
97	ipc_call_t answer;	97	ipc_call_t answer;
98		98
99	/* Resolve the path to the mountpoint. */	99	/* Resolve the path to the mountpoint. */
100	fibril_rwlock_write_lock(&namespace_rwlock);	100	fibril_rwlock_write_lock(&namespace_rwlock);
101	if (rootfs.fs_handle) {	101	if (rootfs.fs_handle) {
102	/* We already have the root FS. */	102	/* We already have the root FS. */
103	if (str_cmp(mp, "/") == 0) {	103	if (str_cmp(mp, "/") == 0) {
104	/* Trying to mount root FS over root FS */	104	/* Trying to mount root FS over root FS */
105	fibril_rwlock_write_unlock(&namespace_rwlock);	105	fibril_rwlock_write_unlock(&namespace_rwlock);
106	ipc_answer_0(rid, EBUSY);	106	ipc_answer_0(rid, EBUSY);
107	return;	107	return;
108	}	108	}
109		109
110	rc = vfs_lookup_internal(mp, L_DIRECTORY, &mp_res, NULL);	110	rc = vfs_lookup_internal(mp, L_DIRECTORY, &mp_res, NULL);
111	if (rc != EOK) {	111	if (rc != EOK) {
112	/* The lookup failed for some reason. */	112	/* The lookup failed for some reason. */
113	fibril_rwlock_write_unlock(&namespace_rwlock);	113	fibril_rwlock_write_unlock(&namespace_rwlock);
114	ipc_answer_0(rid, rc);	114	ipc_answer_0(rid, rc);
115	return;	115	return;
116	}	116	}
117		117
118	mp_node = vfs_node_get(&mp_res);	118	mp_node = vfs_node_get(&mp_res);
119	if (!mp_node) {	119	if (!mp_node) {
120	fibril_rwlock_write_unlock(&namespace_rwlock);	120	fibril_rwlock_write_unlock(&namespace_rwlock);
121	ipc_answer_0(rid, ENOMEM);	121	ipc_answer_0(rid, ENOMEM);
122	return;	122	return;
123	}	123	}
124		124
125	/*	125	/*
126	* Now we hold a reference to mp_node.	126	* Now we hold a reference to mp_node.
127	* It will be dropped upon the corresponding VFS_UNMOUNT.	127	* It will be dropped upon the corresponding VFS_UNMOUNT.
128	* This prevents the mount point from being deleted.	128	* This prevents the mount point from being deleted.
129	*/	129	*/
130	} else {	130	} else {
131	/* We still don't have the root file system mounted. */	131	/* We still don't have the root file system mounted. */
132	if (str_cmp(mp, "/") == 0) {	132	if (str_cmp(mp, "/") == 0) {
133	/*	133	/*
134	* For this simple, but important case,	134	* For this simple, but important case,
135	* we are almost done.	135	* we are almost done.
136	*/	136	*/
137		137
138	/* Tell the mountee that it is being mounted. */	138	/* Tell the mountee that it is being mounted. */
139	phone = vfs_grab_phone(fs_handle);	139	phone = vfs_grab_phone(fs_handle);
140	msg = async_send_1(phone, VFS_MOUNTED,	140	msg = async_send_1(phone, VFS_MOUNTED,
141	(ipcarg_t) dev_handle, &answer);	141	(ipcarg_t) dev_handle, &answer);
142	/* send the mount options */	142	/* send the mount options */
143	rc = ipc_data_write_start(phone, (void *)opts,	143	rc = ipc_data_write_start(phone, (void *)opts,
144	str_size(opts));	144	str_size(opts));
145	if (rc != EOK) {	145	if (rc != EOK) {
146	vfs_release_phone(phone);	-
147	async_wait_for(msg, NULL);	146	async_wait_for(msg, NULL);
-		147	vfs_release_phone(phone);
148	fibril_rwlock_write_unlock(&namespace_rwlock);	148	fibril_rwlock_write_unlock(&namespace_rwlock);
149	ipc_answer_0(rid, rc);	149	ipc_answer_0(rid, rc);
150	return;	150	return;
151	}	151	}
152	vfs_release_phone(phone);	-
153	async_wait_for(msg, &rc);	152	async_wait_for(msg, &rc);
-		153	vfs_release_phone(phone);
154		154
155	if (rc != EOK) {	155	if (rc != EOK) {
156	fibril_rwlock_write_unlock(&namespace_rwlock);	156	fibril_rwlock_write_unlock(&namespace_rwlock);
157	ipc_answer_0(rid, rc);	157	ipc_answer_0(rid, rc);
158	return;	158	return;
159	}	159	}
160		160
161	rindex = (fs_index_t) IPC_GET_ARG1(answer);	161	rindex = (fs_index_t) IPC_GET_ARG1(answer);
162	rsize = (size_t) IPC_GET_ARG2(answer);	162	rsize = (size_t) IPC_GET_ARG2(answer);
163	rlnkcnt = (unsigned) IPC_GET_ARG3(answer);	163	rlnkcnt = (unsigned) IPC_GET_ARG3(answer);
164		164
165	mr_res.triplet.fs_handle = fs_handle;	165	mr_res.triplet.fs_handle = fs_handle;
166	mr_res.triplet.dev_handle = dev_handle;	166	mr_res.triplet.dev_handle = dev_handle;
167	mr_res.triplet.index = rindex;	167	mr_res.triplet.index = rindex;
168	mr_res.size = rsize;	168	mr_res.size = rsize;
169	mr_res.lnkcnt = rlnkcnt;	169	mr_res.lnkcnt = rlnkcnt;
170	mr_res.type = VFS_NODE_DIRECTORY;	170	mr_res.type = VFS_NODE_DIRECTORY;
171		171
172	rootfs.fs_handle = fs_handle;	172	rootfs.fs_handle = fs_handle;
173	rootfs.dev_handle = dev_handle;	173	rootfs.dev_handle = dev_handle;
174		174
175	/* Add reference to the mounted root. */	175	/* Add reference to the mounted root. */
176	mr_node = vfs_node_get(&mr_res);	176	mr_node = vfs_node_get(&mr_res);
177	assert(mr_node);	177	assert(mr_node);
178		178
179	fibril_rwlock_write_unlock(&namespace_rwlock);	179	fibril_rwlock_write_unlock(&namespace_rwlock);
180	ipc_answer_0(rid, rc);	180	ipc_answer_0(rid, rc);
181	return;	181	return;
182	} else {	182	} else {
183	/*	183	/*
184	* We can't resolve this without the root filesystem	184	* We can't resolve this without the root filesystem
185	* being mounted first.	185	* being mounted first.
186	*/	186	*/
187	fibril_rwlock_write_unlock(&namespace_rwlock);	187	fibril_rwlock_write_unlock(&namespace_rwlock);
188	ipc_answer_0(rid, ENOENT);	188	ipc_answer_0(rid, ENOENT);
189	return;	189	return;
190	}	190	}
191	}	191	}
192		192
193	/*	193	/*
194	* At this point, we have all necessary pieces: file system and device	194	* At this point, we have all necessary pieces: file system and device
195	* handles, and we know the mount point VFS node.	195	* handles, and we know the mount point VFS node.
196	*/	196	*/
197		197
198	int mountee_phone = vfs_grab_phone(fs_handle);	198	int mountee_phone = vfs_grab_phone(fs_handle);
199	assert(mountee_phone >= 0);	199	assert(mountee_phone >= 0);
200	vfs_release_phone(mountee_phone);	-
201		200
202	phone = vfs_grab_phone(mp_res.triplet.fs_handle);	201	phone = vfs_grab_phone(mp_res.triplet.fs_handle);
203	msg = async_send_4(phone, VFS_MOUNT,	202	msg = async_send_4(phone, VFS_MOUNT,
204	(ipcarg_t) mp_res.triplet.dev_handle,	203	(ipcarg_t) mp_res.triplet.dev_handle,
205	(ipcarg_t) mp_res.triplet.index,	204	(ipcarg_t) mp_res.triplet.index,
206	(ipcarg_t) fs_handle,	205	(ipcarg_t) fs_handle,
207	(ipcarg_t) dev_handle, &answer);	206	(ipcarg_t) dev_handle, &answer);
208		207
209	/* send connection */	208	/* send connection */
210	rc = async_req_1_0(phone, IPC_M_CONNECTION_CLONE, mountee_phone);	209	rc = async_req_1_0(phone, IPC_M_CONNECTION_CLONE, mountee_phone);
211	if (rc != EOK) {	210	if (rc != EOK) {
212	vfs_release_phone(phone);	-
213	async_wait_for(msg, NULL);	211	async_wait_for(msg, NULL);
-		212	vfs_release_phone(mountee_phone);
-		213	vfs_release_phone(phone);
214	/* Mount failed, drop reference to mp_node. */	214	/* Mount failed, drop reference to mp_node. */
215	if (mp_node)	215	if (mp_node)
216	vfs_node_put(mp_node);	216	vfs_node_put(mp_node);
217	ipc_answer_0(rid, rc);	217	ipc_answer_0(rid, rc);
218	fibril_rwlock_write_unlock(&namespace_rwlock);	218	fibril_rwlock_write_unlock(&namespace_rwlock);
219	return;	219	return;
220	}	220	}
-		221
-		222	vfs_release_phone(mountee_phone);
221		223
222	/* send the mount options */	224	/* send the mount options */
223	rc = ipc_data_write_start(phone, (void *)opts, str_size(opts));	225	rc = ipc_data_write_start(phone, (void *)opts, str_size(opts));
224	if (rc != EOK) {	226	if (rc != EOK) {
225	vfs_release_phone(phone);	-
226	async_wait_for(msg, NULL);	227	async_wait_for(msg, NULL);
-		228	vfs_release_phone(phone);
227	/* Mount failed, drop reference to mp_node. */	229	/* Mount failed, drop reference to mp_node. */
228	if (mp_node)	230	if (mp_node)
229	vfs_node_put(mp_node);	231	vfs_node_put(mp_node);
230	fibril_rwlock_write_unlock(&namespace_rwlock);	232	fibril_rwlock_write_unlock(&namespace_rwlock);
231	ipc_answer_0(rid, rc);	233	ipc_answer_0(rid, rc);
232	return;	234	return;
233	}	235	}
234	vfs_release_phone(phone);	-
235	async_wait_for(msg, &rc);	236	async_wait_for(msg, &rc);
-		237	vfs_release_phone(phone);
236		238
237	if (rc == EOK) {	239	if (rc == EOK) {
238	rindex = (fs_index_t) IPC_GET_ARG1(answer);	240	rindex = (fs_index_t) IPC_GET_ARG1(answer);
239	rsize = (size_t) IPC_GET_ARG2(answer);	241	rsize = (size_t) IPC_GET_ARG2(answer);
240	rlnkcnt = (unsigned) IPC_GET_ARG3(answer);	242	rlnkcnt = (unsigned) IPC_GET_ARG3(answer);
241		243
242	mr_res.triplet.fs_handle = fs_handle;	244	mr_res.triplet.fs_handle = fs_handle;
243	mr_res.triplet.dev_handle = dev_handle;	245	mr_res.triplet.dev_handle = dev_handle;
244	mr_res.triplet.index = rindex;	246	mr_res.triplet.index = rindex;
245	mr_res.size = rsize;	247	mr_res.size = rsize;
246	mr_res.lnkcnt = rlnkcnt;	248	mr_res.lnkcnt = rlnkcnt;
247	mr_res.type = VFS_NODE_DIRECTORY;	249	mr_res.type = VFS_NODE_DIRECTORY;
248		250
249	/* Add reference to the mounted root. */	251	/* Add reference to the mounted root. */
250	mr_node = vfs_node_get(&mr_res);	252	mr_node = vfs_node_get(&mr_res);
251	assert(mr_node);	253	assert(mr_node);
252	} else {	254	} else {
253	/* Mount failed, drop reference to mp_node. */	255	/* Mount failed, drop reference to mp_node. */
254	if (mp_node)	256	if (mp_node)
255	vfs_node_put(mp_node);	257	vfs_node_put(mp_node);
256	}	258	}
257		259
258	ipc_answer_0(rid, rc);	260	ipc_answer_0(rid, rc);
259	fibril_rwlock_write_unlock(&namespace_rwlock);	261	fibril_rwlock_write_unlock(&namespace_rwlock);
260	}	262	}
261		263
262	/** Process pending mount requests */	264	/** Process pending mount requests */
263	void vfs_process_pending_mount(void)	265	void vfs_process_pending_mount(void)
264	{	266	{
265	link_t *cur;	267	link_t *cur;
266		268
267	while (true) {	269	while (true) {
268	fibril_mutex_lock(&fs_head_lock);	270	fibril_mutex_lock(&fs_head_lock);
269	while (!pending_new_fs)	271	while (!pending_new_fs)
270	fibril_condvar_wait(&pending_cv, &fs_head_lock);	272	fibril_condvar_wait(&pending_cv, &fs_head_lock);
271	rescan:	273	rescan:
272	for (cur = pending_req.next; cur != &pending_req;	274	for (cur = pending_req.next; cur != &pending_req;
273	cur = cur->next) {	275	cur = cur->next) {
274	pending_req_t *pr = list_get_instance(cur,	276	pending_req_t *pr = list_get_instance(cur,
275	pending_req_t, link);	277	pending_req_t, link);
276	fs_handle_t fs_handle = fs_name_to_handle(pr->fs_name,	278	fs_handle_t fs_handle = fs_name_to_handle(pr->fs_name,
277	false);	279	false);
278	if (!fs_handle)	280	if (!fs_handle)
279	continue;	281	continue;
280		282
281	/* Acknowledge that we know fs_name. */	283	/* Acknowledge that we know fs_name. */
282	ipc_answer_0(pr->callid, EOK);	284	ipc_answer_0(pr->callid, EOK);
283		285
284	list_remove(cur);	286	list_remove(cur);
285	fibril_mutex_unlock(&fs_head_lock);	287	fibril_mutex_unlock(&fs_head_lock);
286		288
287	/* Do the mount */	289	/* Do the mount */
288	vfs_mount_internal(pr->rid, pr->dev_handle, fs_handle,	290	vfs_mount_internal(pr->rid, pr->dev_handle, fs_handle,
289	pr->mp, pr->opts);	291	pr->mp, pr->opts);
290		292
291	free(pr->fs_name);	293	free(pr->fs_name);
292	free(pr->mp);	294	free(pr->mp);
293	free(pr->opts);	295	free(pr->opts);
294	free(pr);	296	free(pr);
295		297
296	fibril_mutex_lock(&fs_head_lock);	298	fibril_mutex_lock(&fs_head_lock);
297	goto rescan;	299	goto rescan;
298	}	300	}
299	pending_new_fs = false;	301	pending_new_fs = false;
300	fibril_mutex_unlock(&fs_head_lock);	302	fibril_mutex_unlock(&fs_head_lock);
301	}	303	}
302	}	304	}
303		305
304	void vfs_mount(ipc_callid_t rid, ipc_call_t *request)	306	void vfs_mount(ipc_callid_t rid, ipc_call_t *request)
305	{	307	{
306	/*	308	/*
307	* We expect the library to do the device-name to device-handle	309	* We expect the library to do the device-name to device-handle
308	* translation for us, thus the device handle will arrive as ARG1	310	* translation for us, thus the device handle will arrive as ARG1
309	* in the request.	311	* in the request.
310	*/	312	*/
311	dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);	313	dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
312		314
313	/*	315	/*
314	* Mount flags are passed as ARG2.	316	* Mount flags are passed as ARG2.
315	*/	317	*/
316	unsigned int flags = (unsigned int) IPC_GET_ARG2(*request);	318	unsigned int flags = (unsigned int) IPC_GET_ARG2(*request);
317		319
318	/*	320	/*
319	* For now, don't make use of ARG3, but it can be used to	321	* For now, don't make use of ARG3, but it can be used to
320	* carry mount options in the future.	322	* carry mount options in the future.
321	*/	323	*/
322		324
323	/* We want the client to send us the mount point. */	325	/* We want the client to send us the mount point. */
324	ipc_callid_t callid;	326	ipc_callid_t callid;
325	size_t size;	327	size_t size;
326	if (!ipc_data_write_receive(&callid, &size)) {	328	if (!ipc_data_write_receive(&callid, &size)) {
327	ipc_answer_0(callid, EINVAL);	329	ipc_answer_0(callid, EINVAL);
328	ipc_answer_0(rid, EINVAL);	330	ipc_answer_0(rid, EINVAL);
329	return;	331	return;
330	}	332	}
331		333
332	/* Check whether size is reasonable wrt. the mount point. */	334	/* Check whether size is reasonable wrt. the mount point. */
333	if ((size < 1) \|\| (size > MAX_PATH_LEN)) {	335	if ((size < 1) \|\| (size > MAX_PATH_LEN)) {
334	ipc_answer_0(callid, EINVAL);	336	ipc_answer_0(callid, EINVAL);
335	ipc_answer_0(rid, EINVAL);	337	ipc_answer_0(rid, EINVAL);
336	return;	338	return;
337	}	339	}
338		340
339	/* Allocate buffer for the mount point data being received. */	341	/* Allocate buffer for the mount point data being received. */
340	char *mp = malloc(size + 1);	342	char *mp = malloc(size + 1);
341	if (!mp) {	343	if (!mp) {
342	ipc_answer_0(callid, ENOMEM);	344	ipc_answer_0(callid, ENOMEM);
343	ipc_answer_0(rid, ENOMEM);	345	ipc_answer_0(rid, ENOMEM);
344	return;	346	return;
345	}	347	}
346		348
347	/* Deliver the mount point. */	349	/* Deliver the mount point. */
348	ipcarg_t retval = ipc_data_write_finalize(callid, mp, size);	350	ipcarg_t retval = ipc_data_write_finalize(callid, mp, size);
349	if (retval != EOK) {	351	if (retval != EOK) {
350	ipc_answer_0(rid, retval);	352	ipc_answer_0(rid, retval);
351	free(mp);	353	free(mp);
352	return;	354	return;
353	}	355	}
354	mp[size] = '\0';	356	mp[size] = '\0';
355		357
356	/* Now we expect to receive the mount options. */	358	/* Now we expect to receive the mount options. */
357	if (!ipc_data_write_receive(&callid, &size)) {	359	if (!ipc_data_write_receive(&callid, &size)) {
358	ipc_answer_0(callid, EINVAL);	360	ipc_answer_0(callid, EINVAL);
359	ipc_answer_0(rid, EINVAL);	361	ipc_answer_0(rid, EINVAL);
360	free(mp);	362	free(mp);
361	return;	363	return;
362	}	364	}
363		365
364	/* Check the offered options size. */	366	/* Check the offered options size. */
365	if (size < 0 \|\| size > MAX_MNTOPTS_LEN) {	367	if (size < 0 \|\| size > MAX_MNTOPTS_LEN) {
366	ipc_answer_0(callid, EINVAL);	368	ipc_answer_0(callid, EINVAL);
367	ipc_answer_0(rid, EINVAL);	369	ipc_answer_0(rid, EINVAL);
368	free(mp);	370	free(mp);
369	return;	371	return;
370	}	372	}
371		373
372	/* Allocate buffer for the mount options. */	374	/* Allocate buffer for the mount options. */
373	char opts = (char ) malloc(size + 1);	375	char opts = (char ) malloc(size + 1);
374	if (!opts) {	376	if (!opts) {
375	ipc_answer_0(callid, ENOMEM);	377	ipc_answer_0(callid, ENOMEM);
376	ipc_answer_0(rid, ENOMEM);	378	ipc_answer_0(rid, ENOMEM);
377	free(mp);	379	free(mp);
378	return;	380	return;
379	}	381	}
380		382
381	/* Deliver the mount options. */	383	/* Deliver the mount options. */
382	retval = ipc_data_write_finalize(callid, opts, size);	384	retval = ipc_data_write_finalize(callid, opts, size);
383	if (retval != EOK) {	385	if (retval != EOK) {
384	ipc_answer_0(rid, retval);	386	ipc_answer_0(rid, retval);
385	free(mp);	387	free(mp);
386	free(opts);	388	free(opts);
387	return;	389	return;
388	}	390	}
389	opts[size] = '\0';	391	opts[size] = '\0';
390		392
391	/*	393	/*
392	* Now, we expect the client to send us data with the name of the file	394	* Now, we expect the client to send us data with the name of the file
393	* system.	395	* system.
394	*/	396	*/
395	if (!ipc_data_write_receive(&callid, &size)) {	397	if (!ipc_data_write_receive(&callid, &size)) {
396	ipc_answer_0(callid, EINVAL);	398	ipc_answer_0(callid, EINVAL);
397	ipc_answer_0(rid, EINVAL);	399	ipc_answer_0(rid, EINVAL);
398	free(mp);	400	free(mp);
399	free(opts);	401	free(opts);
400	return;	402	return;
401	}	403	}
402		404
403	/*	405	/*
404	* Don't receive more than is necessary for storing a full file system	406	* Don't receive more than is necessary for storing a full file system
405	* name.	407	* name.
406	*/	408	*/
407	if ((size < 1) \|\| (size > FS_NAME_MAXLEN)) {	409	if ((size < 1) \|\| (size > FS_NAME_MAXLEN)) {
408	ipc_answer_0(callid, EINVAL);	410	ipc_answer_0(callid, EINVAL);
409	ipc_answer_0(rid, EINVAL);	411	ipc_answer_0(rid, EINVAL);
410	free(mp);	412	free(mp);
411	free(opts);	413	free(opts);
412	return;	414	return;
413	}	415	}
414		416
415	/*	417	/*
416	* Allocate buffer for file system name.	418	* Allocate buffer for file system name.
417	*/	419	*/
418	char fs_name = (char ) malloc(size + 1);	420	char fs_name = (char ) malloc(size + 1);
419	if (fs_name == NULL) {	421	if (fs_name == NULL) {
420	ipc_answer_0(callid, ENOMEM);	422	ipc_answer_0(callid, ENOMEM);
421	ipc_answer_0(rid, ENOMEM);	423	ipc_answer_0(rid, ENOMEM);
422	free(mp);	424	free(mp);
423	free(opts);	425	free(opts);
424	return;	426	return;
425	}	427	}
426		428
427	/* Deliver the file system name. */	429	/* Deliver the file system name. */
428	retval = ipc_data_write_finalize(callid, fs_name, size);	430	retval = ipc_data_write_finalize(callid, fs_name, size);
429	if (retval != EOK) {	431	if (retval != EOK) {
430	ipc_answer_0(rid, retval);	432	ipc_answer_0(rid, retval);
431	free(mp);	433	free(mp);
432	free(opts);	434	free(opts);
433	free(fs_name);	435	free(fs_name);
434	return;	436	return;
435	}	437	}
436	fs_name[size] = '\0';	438	fs_name[size] = '\0';
437		439
438	/*	440	/*
439	* Wait for IPC_M_PING so that we can return an error if we don't know	441	* Wait for IPC_M_PING so that we can return an error if we don't know
440	* fs_name.	442	* fs_name.
441	*/	443	*/
442	ipc_call_t data;	444	ipc_call_t data;
443	callid = async_get_call(&data);	445	callid = async_get_call(&data);
444	if (IPC_GET_METHOD(data) != IPC_M_PING) {	446	if (IPC_GET_METHOD(data) != IPC_M_PING) {
445	ipc_answer_0(callid, ENOTSUP);	447	ipc_answer_0(callid, ENOTSUP);
446	ipc_answer_0(rid, ENOTSUP);	448	ipc_answer_0(rid, ENOTSUP);
447	free(mp);	449	free(mp);
448	free(opts);	450	free(opts);
449	free(fs_name);	451	free(fs_name);
450	return;	452	return;
451	}	453	}
452		454
453	/*	455	/*
454	* Check if we know a file system with the same name as is in fs_name.	456	* Check if we know a file system with the same name as is in fs_name.
455	* This will also give us its file system handle.	457	* This will also give us its file system handle.
456	*/	458	*/
457	fibril_mutex_lock(&fs_head_lock);	459	fibril_mutex_lock(&fs_head_lock);
458	fs_handle_t fs_handle = fs_name_to_handle(fs_name, false);	460	fs_handle_t fs_handle = fs_name_to_handle(fs_name, false);
459	if (!fs_handle) {	461	if (!fs_handle) {
460	if (flags & IPC_FLAG_BLOCKING) {	462	if (flags & IPC_FLAG_BLOCKING) {
461	pending_req_t *pr;	463	pending_req_t *pr;
462		464
463	/* Blocking mount, add to pending list */	465	/* Blocking mount, add to pending list */
464	pr = (pending_req_t *) malloc(sizeof(pending_req_t));	466	pr = (pending_req_t *) malloc(sizeof(pending_req_t));
465	if (!pr) {	467	if (!pr) {
466	fibril_mutex_unlock(&fs_head_lock);	468	fibril_mutex_unlock(&fs_head_lock);
467	ipc_answer_0(callid, ENOMEM);	469	ipc_answer_0(callid, ENOMEM);
468	ipc_answer_0(rid, ENOMEM);	470	ipc_answer_0(rid, ENOMEM);
469	free(mp);	471	free(mp);
470	free(fs_name);	472	free(fs_name);
471	free(opts);	473	free(opts);
472	return;	474	return;
473	}	475	}
474		476
475	pr->fs_name = fs_name;	477	pr->fs_name = fs_name;
476	pr->mp = mp;	478	pr->mp = mp;
477	pr->opts = opts;	479	pr->opts = opts;
478	pr->callid = callid;	480	pr->callid = callid;
479	pr->rid = rid;	481	pr->rid = rid;
480	pr->dev_handle = dev_handle;	482	pr->dev_handle = dev_handle;
481	link_initialize(&pr->link);	483	link_initialize(&pr->link);
482	list_append(&pr->link, &pending_req);	484	list_append(&pr->link, &pending_req);
483	fibril_mutex_unlock(&fs_head_lock);	485	fibril_mutex_unlock(&fs_head_lock);
484	return;	486	return;
485	}	487	}
486		488
487	fibril_mutex_unlock(&fs_head_lock);	489	fibril_mutex_unlock(&fs_head_lock);
488	ipc_answer_0(callid, ENOENT);	490	ipc_answer_0(callid, ENOENT);
489	ipc_answer_0(rid, ENOENT);	491	ipc_answer_0(rid, ENOENT);
490	free(mp);	492	free(mp);
491	free(fs_name);	493	free(fs_name);
492	free(opts);	494	free(opts);

Subversion Repositories HelenOS

(root)/trunk/uspace/srv/vfs/vfs_ops.c @ 3662 – Rev 4539 → 4551