source: mainline/uspace/srv/fs/udf/udf_ops.c@ d0a1e9b6

/*
 * Copyright (c) 2008 Jakub Jermar
 * Copyright (c) 2012 Julia Medvedeva
 * 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 udf_ops.c
 * @brief Implementation of VFS operations for the UDF file system
 *        server.
 */

#include <libfs.h>
#include <block.h>
#include <ipc/services.h>
#include <ipc/loc.h>
#include <macros.h>
#include <async.h>
#include <errno.h>
#include <str.h>
#include <byteorder.h>
#include <adt/hash_table.h>
#include <adt/list.h>
#include <assert.h>
#include <fibril_synch.h>
#include <sys/mman.h>
#include <align.h>
#include <malloc.h>
#include <inttypes.h>
#include <io/log.h>
#include "../../vfs/vfs.h"
#include "udf.h"
#include "udf_cksum.h"
#include "udf_volume.h"
#include "udf_idx.h"
#include "udf_file.h"
#include "udf_osta.h"

/** Mutex protecting the list of cached free nodes. */
static FIBRIL_MUTEX_INITIALIZE(ffn_mutex);

/** List of cached free nodes. */
static LIST_INITIALIZE(ffn_list);

static int udf_node_get(fs_node_t **rfn, service_id_t service_id,
    fs_index_t index)
{
        udf_instance_t *instance;
        int rc = fs_instance_get(service_id, (void **) &instance);
        if (rc != EOK)
                return rc;
        
        udf_node_t *node;
        rc = udf_idx_get(&node, instance, index);
        if (rc != EOK) {
                rc = udf_idx_add(&node, instance, index);
                if (rc != EOK)
                        return rc;
                
                rc = udf_node_get_core(node);
                if (rc != EOK) {
                        udf_idx_del(node);
                        return rc;
                }
        }
        
        *rfn = FS_NODE(node);
        return EOK;
}

static int udf_root_get(fs_node_t **rfn, service_id_t service_id)
{
        udf_instance_t *instance;
        int rc = fs_instance_get(service_id, (void **) &instance);
        if (rc != EOK)
                return rc;
        
        return udf_node_get(rfn, service_id,
            instance->volumes[DEFAULT_VOL].root_dir);
}

static service_id_t udf_service_get(fs_node_t *node)
{
        udf_node_t *udfn = UDF_NODE(node);
        if (udfn)
                return udfn->instance->service_id;
        
        return 0;
}

static int udf_match(fs_node_t **rfn, fs_node_t *pfn, const char *component)
{
        char *name = malloc(MAX_FILE_NAME_LEN + 1);
        if (name == NULL)
                return ENOMEM;
        
        block_t *block = NULL;
        udf_file_identifier_descriptor_t *fid = NULL;
        size_t pos = 0;
        
        while (udf_get_fid(&fid, &block, UDF_NODE(pfn), pos) == EOK) {
                udf_long_ad_t long_ad = fid->icb;
                
                udf_to_unix_name(name, MAX_FILE_NAME_LEN,
                    (char *) fid->implementation_use + FLE16(fid->lenght_iu),
                    fid->lenght_file_id, &UDF_NODE(pfn)->instance->charset);
                
                if (stricmp(name, component) == 0) {
                        int rc = udf_node_get(rfn, udf_service_get(pfn),
                            udf_long_ad_to_pos(UDF_NODE(pfn)->instance, &long_ad));
                        
                        if (block != NULL)
                                block_put(block);
                        
                        free(name);
                        return rc;
                }
                
                if (block != NULL) {
                        int rc = block_put(block);
                        if (rc != EOK)
                                return rc;
                }
                
                pos++;
        }
        
        free(name);
        return ENOENT;
}

static int udf_node_open(fs_node_t *fn)
{
        return EOK;
}

static int udf_node_put(fs_node_t *fn)
{
        udf_node_t *node = UDF_NODE(fn);
        if (!node)
                return EINVAL;
        
        fibril_mutex_lock(&node->lock);
        node->ref_cnt--;
        fibril_mutex_unlock(&node->lock);
        
        /* Delete node from hash table and memory */
        if (!node->ref_cnt)
                udf_idx_del(node);
        
        return EOK;
}

static int udf_create_node(fs_node_t **rfn, service_id_t service_id, int flags)
{
        return ENOTSUP;
}

static int udf_destroy_node(fs_node_t *fn)
{
        return ENOTSUP;
}

static int udf_link(fs_node_t *pfn, fs_node_t *cfn, const char *name)
{
        return ENOTSUP;
}

static int udf_unlink(fs_node_t *pfn, fs_node_t *cfn, const char *nm)
{
        return ENOTSUP;
}

static int udf_has_children(bool *has_children, fs_node_t *fn)
{
        *has_children = true;
        return EOK;
}

static fs_index_t udf_index_get(fs_node_t *fn)
{
        udf_node_t *node = UDF_NODE(fn);
        if (node)
                return node->index;
        
        return 0;
}

static aoff64_t udf_size_get(fs_node_t *fn)
{
        udf_node_t *node = UDF_NODE(fn);
        if (node)
                return node->data_size;
        
        return 0;
}

static unsigned int udf_lnkcnt_get(fs_node_t *fn)
{
        udf_node_t *node = UDF_NODE(fn);
        if (node)
                return node->link_cnt;
        
        return 0;
}

static bool udf_is_directory(fs_node_t *fn)
{
        udf_node_t *node = UDF_NODE(fn);
        if (node)
                return node->type == NODE_DIR;
        
        return false;
}

static bool udf_is_file(fs_node_t *fn)
{
        udf_node_t *node = UDF_NODE(fn);
        if (node)
                return node->type == NODE_FILE;
        
        return false;
}

static uint32_t udf_size_block(service_id_t service_id)
{
        udf_instance_t *instance;
        int rc = fs_instance_get(service_id, (void **) &instance);
        if (rc != EOK)
                return rc;

        if (NULL == instance)
                return ENOENT;
        
        return instance->volumes[DEFAULT_VOL].logical_block_size;
}

libfs_ops_t udf_libfs_ops = {
        .root_get = udf_root_get,
        .match = udf_match,
        .node_get = udf_node_get,
        .node_open = udf_node_open,
        .node_put = udf_node_put,
        .create = udf_create_node,
        .destroy = udf_destroy_node,
        .link = udf_link,
        .unlink = udf_unlink,
        .has_children = udf_has_children,
        .index_get = udf_index_get,
        .size_get = udf_size_get,
        .lnkcnt_get = udf_lnkcnt_get,
        .is_directory = udf_is_directory,
        .is_file = udf_is_file,
        .service_get = udf_service_get,
        .size_block = udf_size_block
};

static int udf_mounted(service_id_t service_id, const char *opts,
    fs_index_t *index, aoff64_t *size, unsigned *linkcnt)
{
        enum cache_mode cmode;
        
        /* Check for option enabling write through. */
        if (str_cmp(opts, "wtcache") == 0)
                cmode = CACHE_MODE_WT;
        else
                cmode = CACHE_MODE_WB;
        
        udf_instance_t *instance = malloc(sizeof(udf_instance_t));
        if (!instance)
                return ENOMEM;
        
        instance->sector_size = 0;
        
        /* Check for block size. Will be enhanced later */
        if (str_cmp(opts, "bs=512") == 0)
                instance->sector_size = 512;
        else if (str_cmp(opts, "bs=1024") == 0)
                instance->sector_size = 1024;
        else if (str_cmp(opts, "bs=2048") == 0)
                instance->sector_size = 2048;
        
        /* initialize block cache */
        int rc = block_init(EXCHANGE_SERIALIZE, service_id, MAX_SIZE);
        if (rc != EOK)
                return rc;
        
        rc = fs_instance_create(service_id, instance);
        if (rc != EOK) {
                free(instance);
                block_fini(service_id);
                return rc;
        }
        
        instance->service_id = service_id;
        instance->open_nodes_count = 0;
        
        /* Check Volume Recognition Sequence */
        rc = udf_volume_recongnition(service_id);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_NOTE, "VRS failed");
                fs_instance_destroy(service_id);
                free(instance);
                block_fini(service_id);
                return rc;
        }
        
        /* Search for Anchor Volume Descriptor */
        udf_anchor_volume_descriptor_t avd;
        rc = udf_get_anchor_volume_descriptor(service_id, &avd);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_NOTE, "Anchor read failed");
                fs_instance_destroy(service_id);
                free(instance);
                block_fini(service_id);
                return rc;
        }
        
        log_msg(LOG_DEFAULT, LVL_DEBUG,
            "Volume: Anchor volume descriptor found. Sector size=%" PRIu32,
            instance->sector_size);
        log_msg(LOG_DEFAULT, LVL_DEBUG,
            "Anchor: main sequence [length=%" PRIu32 " (bytes), start=%"
            PRIu32 " (sector)]", avd.main_extent.length,
            avd.main_extent.location);
        log_msg(LOG_DEFAULT, LVL_DEBUG,
            "Anchor: reserve sequence [length=%" PRIu32 " (bytes), start=%"
            PRIu32 " (sector)]", avd.reserve_extent.length,
            avd.reserve_extent.location);
        
        /* Initialize the block cache */
        rc = block_cache_init(service_id, instance->sector_size, 0, cmode);
        if (rc != EOK) {
                fs_instance_destroy(service_id);
                free(instance);
                block_fini(service_id);
                return rc;
        }
        
        /* Read Volume Descriptor Sequence */
        rc = udf_read_volume_descriptor_sequence(service_id, avd.main_extent);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_NOTE, "Volume Descriptor Sequence read failed");
                fs_instance_destroy(service_id);
                free(instance);
                block_cache_fini(service_id);
                block_fini(service_id);
                return rc;
        }
        
        fs_node_t *rfn;
        rc = udf_node_get(&rfn, service_id, instance->volumes[DEFAULT_VOL].root_dir);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_NOTE, "Can't create root node");
                fs_instance_destroy(service_id);
                free(instance);
                block_cache_fini(service_id);
                block_fini(service_id);
                return rc;
        }
        
        udf_node_t *node = UDF_NODE(rfn);
        *index = instance->volumes[DEFAULT_VOL].root_dir;
        *size = node->data_size;
        *linkcnt = node->link_cnt;
        
        return EOK;
}

static int udf_unmounted(service_id_t service_id)
{
        fs_node_t *fn;
        int rc = udf_root_get(&fn, service_id);
        if (rc != EOK)
                return rc;
        
        udf_node_t *nodep = UDF_NODE(fn);
        udf_instance_t *instance = nodep->instance;
        
        /*
         * We expect exactly two references on the root node.
         * One for the udf_root_get() above and one created in
         * udf_mounted().
         */
        if (nodep->ref_cnt != 2) {
                udf_node_put(fn);
                return EBUSY;
        }
        
        /*
         * Put the root node twice.
         */
        udf_node_put(fn);
        udf_node_put(fn);
        
        fs_instance_destroy(service_id);
        free(instance);
        block_cache_fini(service_id);
        block_fini(service_id);
        
        return EOK;
}

static int udf_read(service_id_t service_id, fs_index_t index, aoff64_t pos,
    size_t *rbytes)
{
        udf_instance_t *instance;
        int rc = fs_instance_get(service_id, (void **) &instance);
        if (rc != EOK)
                return rc;
        
        fs_node_t *rfn;
        rc = udf_node_get(&rfn, service_id, index);
        if (rc != EOK)
                return rc;
        
        udf_node_t *node = UDF_NODE(rfn);
        
        ipc_callid_t callid;
        size_t len = 0;
        if (!async_data_read_receive(&callid, &len)) {
                async_answer_0(callid, EINVAL);
                udf_node_put(rfn);
                return EINVAL;
        }
        
        if (node->type == NODE_FILE) {
                if (pos >= node->data_size) {
                        *rbytes = 0;
                        async_data_read_finalize(callid, NULL, 0);
                        udf_node_put(rfn);
                        return EOK;
                }
                
                size_t read_len = 0;
                if (node->data == NULL)
                        rc = udf_read_file(&read_len, callid, node, pos, len);
                else {
                        /* File in allocation descriptors area */
                        read_len = (len < node->data_size) ? len : node->data_size;
                        async_data_read_finalize(callid, node->data + pos, read_len);
                        rc = EOK;
                }
                
                *rbytes = read_len;
                (void) udf_node_put(rfn);
                return rc;
        } else {
                block_t *block = NULL;
                udf_file_identifier_descriptor_t *fid = NULL;
                if (udf_get_fid(&fid, &block, node, pos) == EOK) {
                        char *name = malloc(MAX_FILE_NAME_LEN + 1);
                        
                        // FIXME: Check for NULL return value
                        
                        udf_to_unix_name(name, MAX_FILE_NAME_LEN,
                            (char *) fid->implementation_use + FLE16(fid->lenght_iu),
                            fid->lenght_file_id, &node->instance->charset);
                        
                        async_data_read_finalize(callid, name, str_size(name) + 1);
                        *rbytes = 1;
                        free(name);
                        udf_node_put(rfn);
                        
                        if (block != NULL)
                                return block_put(block);
                        
                        return EOK;
                } else {
                        *rbytes = 0;
                        udf_node_put(rfn);
                        async_answer_0(callid, ENOENT);
                        return ENOENT;
                }
        }
}

static int udf_close(service_id_t service_id, fs_index_t index)
{
        return EOK;
}

static int udf_sync(service_id_t service_id, fs_index_t index)
{
        return ENOTSUP;
}

static int udf_write(service_id_t service_id, fs_index_t index, aoff64_t pos,
    size_t *wbytes, aoff64_t *nsize)
{
        return ENOTSUP;
}

static int udf_truncate(service_id_t service_id, fs_index_t index,
    aoff64_t size)
{
        return ENOTSUP;
}

static int udf_destroy(service_id_t service_id, fs_index_t index)
{
        return ENOTSUP;
}

vfs_out_ops_t udf_ops = {
        .mounted = udf_mounted,
        .unmounted = udf_unmounted,
        .read = udf_read,
        .write = udf_write,
        .truncate = udf_truncate,
        .close = udf_close,
        .destroy = udf_destroy,
        .sync = udf_sync
};

/**
 * @}
 */