WebSVN – HelenOS – Diff – /branches/dd/uspace/lib/libblock/libblock.c


/*
 * Copyright (c) 2008 Jakub Jermar
 * Copyright (c) 2008 Martin Decky
 * 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 libblock
 * @{
 */
/**
 * @file
 * @brief
 */
 
#include "libblock.h"
#include "../../srv/vfs/vfs.h"
#include <ipc/devmap.h>
#include <ipc/bd.h>
#include <ipc/services.h>
#include <errno.h>
#include <sys/mman.h>
#include <async.h>
#include <ipc/ipc.h>
#include <as.h>
#include <assert.h>
#include <futex.h>
#include <adt/list.h>
#include <adt/hash_table.h>
#include <mem.h>
 
/** Lock protecting the device connection list */
static futex_t dcl_lock = FUTEX_INITIALIZER;
/** Device connection list head. */
static LIST_INITIALIZE(dcl_head);
 
#define CACHE_BUCKETS_LOG2      10
#define CACHE_BUCKETS           (1 << CACHE_BUCKETS_LOG2)
 
typedef struct {
    futex_t lock;
    size_t block_size;      /**< Block size. */
    unsigned block_count;       /**< Total number of blocks. */
    hash_table_t block_hash;
    link_t free_head;
} cache_t;
 
typedef struct {
    link_t link;
    dev_handle_t dev_handle;
    int dev_phone;
    void *com_area;
    size_t com_size;
    void *bb_buf;
    off_t bb_off;
    size_t bb_size;
    cache_t *cache;
} devcon_t;
 
static devcon_t *devcon_search(dev_handle_t dev_handle)
{
    link_t *cur;
 
    futex_down(&dcl_lock);
    for (cur = dcl_head.next; cur != &dcl_head; cur = cur->next) {
        devcon_t *devcon = list_get_instance(cur, devcon_t, link);
        if (devcon->dev_handle == dev_handle) {
            futex_up(&dcl_lock);
            return devcon;
        }
    }
    futex_up(&dcl_lock);
    return NULL;
}
 
static int devcon_add(dev_handle_t dev_handle, int dev_phone, void *com_area,
   size_t com_size)
{
    link_t *cur;
    devcon_t *devcon;
 
    devcon = malloc(sizeof(devcon_t));
    if (!devcon)
        return ENOMEM;
   
    link_initialize(&devcon->link);
    devcon->dev_handle = dev_handle;
    devcon->dev_phone = dev_phone;
    devcon->com_area = com_area;
    devcon->com_size = com_size;
    devcon->bb_buf = NULL;
    devcon->bb_off = 0;
    devcon->bb_size = 0;
    devcon->cache = NULL;
 
    futex_down(&dcl_lock);
    for (cur = dcl_head.next; cur != &dcl_head; cur = cur->next) {
        devcon_t *d = list_get_instance(cur, devcon_t, link);
        if (d->dev_handle == dev_handle) {
            futex_up(&dcl_lock);
            free(devcon);
            return EEXIST;
        }
    }
    list_append(&devcon->link, &dcl_head);
    futex_up(&dcl_lock);
    return EOK;
}
 
static void devcon_remove(devcon_t *devcon)
{
    futex_down(&dcl_lock);
    list_remove(&devcon->link);
    futex_up(&dcl_lock);
}
 
int block_init(dev_handle_t dev_handle, size_t com_size)
{
    int rc;
    int dev_phone;
    void *com_area;
   
    com_area = mmap(NULL, com_size, PROTO_READ | PROTO_WRITE,
        MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
    if (!com_area) {
        return ENOMEM;
    }
 
    dev_phone = devmap_device_connect(dev_handle, IPC_FLAG_BLOCKING);
    if (dev_phone < 0) {
        munmap(com_area, com_size);
        return dev_phone;
    }
 
    rc = ipc_share_out_start(dev_phone, com_area,
        AS_AREA_READ | AS_AREA_WRITE);
    if (rc != EOK) {
            munmap(com_area, com_size);
        ipc_hangup(dev_phone);
        return rc;
    }
   
    rc = devcon_add(dev_handle, dev_phone, com_area, com_size);
    if (rc != EOK) {
        munmap(com_area, com_size);
        ipc_hangup(dev_phone);
        return rc;
    }
 
    return EOK;
}
 
void block_fini(dev_handle_t dev_handle)
{
    devcon_t *devcon = devcon_search(dev_handle);
    assert(devcon);
   
    devcon_remove(devcon);
 
    if (devcon->bb_buf)
        free(devcon->bb_buf);
 
    if (devcon->cache) {
        hash_table_destroy(&devcon->cache->block_hash);
        free(devcon->cache);
    }
 
    munmap(devcon->com_area, devcon->com_size);
    ipc_hangup(devcon->dev_phone);
 
    free(devcon);  
}
 
int block_bb_read(dev_handle_t dev_handle, off_t off, size_t size)
{
    void *bb_buf;
    int rc;
 
    devcon_t *devcon = devcon_search(dev_handle);
    if (!devcon)
        return ENOENT;
    if (devcon->bb_buf)
        return EEXIST;
    bb_buf = malloc(size);
    if (!bb_buf)
        return ENOMEM;
   
    off_t bufpos = 0;
    size_t buflen = 0;
    rc = block_read(dev_handle, &bufpos, &buflen, &off,
        bb_buf, size, size);
    if (rc != EOK) {
            free(bb_buf);
        return rc;
    }
    devcon->bb_buf = bb_buf;
    devcon->bb_off = off;
    devcon->bb_size = size;
 
    return EOK;
}
 
void *block_bb_get(dev_handle_t dev_handle)
{
    devcon_t *devcon = devcon_search(dev_handle);
    assert(devcon);
    return devcon->bb_buf;
}
 
static hash_index_t cache_hash(unsigned long *key)
{
    return *key & (CACHE_BUCKETS - 1);
}
 
static int cache_compare(unsigned long *key, hash_count_t keys, link_t *item)
{
    block_t *b = hash_table_get_instance(item, block_t, hash_link);
    return b->boff == *key;
}
 
static void cache_remove_callback(link_t *item)
{
}
 
static hash_table_operations_t cache_ops = {
    .hash = cache_hash,
    .compare = cache_compare,
    .remove_callback = cache_remove_callback
};
 
int block_cache_init(dev_handle_t dev_handle, size_t size, unsigned blocks)
{
    devcon_t *devcon = devcon_search(dev_handle);
    cache_t *cache;
    if (!devcon)
        return ENOENT;
    if (devcon->cache)
        return EEXIST;
    cache = malloc(sizeof(cache_t));
    if (!cache)
        return ENOMEM;
   
    futex_initialize(&cache->lock, 1);
    list_initialize(&cache->free_head);
    cache->block_size = size;
    cache->block_count = blocks;
 
    if (!hash_table_create(&cache->block_hash, CACHE_BUCKETS, 1,
        &cache_ops)) {
        free(cache);
        return ENOMEM;
    }
 
    devcon->cache = cache;
    return EOK;
}
 
static bool cache_can_grow(cache_t *cache)
{
    return true;
}
 
static void block_initialize(block_t *b)
{
    futex_initialize(&b->lock, 1);
    b->refcnt = 1;
    b->dirty = false;
    rwlock_initialize(&b->contents_lock);
    link_initialize(&b->free_link);
    link_initialize(&b->hash_link);
}
 
/** Instantiate a block in memory and get a reference to it.
 *
 * @param dev_handle        Device handle of the block device.
 * @param boff          Block offset.
 * @param flags         If BLOCK_FLAGS_NOREAD is specified, block_get()
 *              will not read the contents of the block from the
 *              device.
 *
 * @return          Block structure.
 */
block_t *block_get(dev_handle_t dev_handle, bn_t boff, int flags)
{
    devcon_t *devcon;
    cache_t *cache;
    block_t *b;
    link_t *l;
    unsigned long key = boff;
   
    devcon = devcon_search(dev_handle);
 
    assert(devcon);
    assert(devcon->cache);
   
    cache = devcon->cache;
    futex_down(&cache->lock);
    l = hash_table_find(&cache->block_hash, &key);
    if (l) {
        /*
         * We found the block in the cache.
         */
        b = hash_table_get_instance(l, block_t, hash_link);
        futex_down(&b->lock);
        if (b->refcnt++ == 0)
            list_remove(&b->free_link);
        futex_up(&b->lock);
        futex_up(&cache->lock);
    } else {
        /*
         * The block was not found in the cache.
         */
        int rc;
        off_t bufpos = 0;
        size_t buflen = 0;
        off_t pos = boff * cache->block_size;
        bool sync = false;
 
        if (cache_can_grow(cache)) {
            /*
             * We can grow the cache by allocating new blocks.
             * Should the allocation fail, we fail over and try to
             * recycle a block from the cache.
             */
            b = malloc(sizeof(block_t));
            if (!b)
                goto recycle;
            b->data = malloc(cache->block_size);
            if (!b->data) {
                free(b);
                goto recycle;
            }
        } else {
            /*
             * Try to recycle a block from the free list.
             */
            unsigned long temp_key;
recycle:
            assert(!list_empty(&cache->free_head));
            l = cache->free_head.next;
            list_remove(l);
            b = hash_table_get_instance(l, block_t, hash_link);
            sync = b->dirty;
            temp_key = b->boff;
            hash_table_remove(&cache->block_hash, &temp_key, 1);
        }
 
        block_initialize(b);
        b->dev_handle = dev_handle;
        b->size = cache->block_size;
        b->boff = boff;
        hash_table_insert(&cache->block_hash, &key, &b->hash_link);
 
        /*
         * Lock the block before releasing the cache lock. Thus we don't
         * kill concurent operations on the cache while doing I/O on the
         * block.
         */
        futex_down(&b->lock);
        futex_up(&cache->lock);
 
        if (sync) {
            /*
             * The block is dirty and needs to be written back to
             * the device before we can read in the new contents.
             */
            abort();    /* TODO: block_write() */
        }
        if (!(flags & BLOCK_FLAGS_NOREAD)) {
            /*
             * The block contains old or no data. We need to read
             * the new contents from the device.
             */
            rc = block_read(dev_handle, &bufpos, &buflen, &pos,
                b->data, cache->block_size, cache->block_size);
            assert(rc == EOK);
        }
 
        futex_up(&b->lock);
    }
    return b;
}
 
/** Release a reference to a block.
 *
 * If the last reference is dropped, the block is put on the free list.
 *
 * @param block     Block of which a reference is to be released.
 */
void block_put(block_t *block)
{
    devcon_t *devcon = devcon_search(block->dev_handle);
    cache_t *cache;
 
    assert(devcon);
    assert(devcon->cache);
 
    cache = devcon->cache;
    futex_down(&cache->lock);
    futex_down(&block->lock);
    if (!--block->refcnt) {
        /*
         * Last reference to the block was dropped, put the block on the
         * free list.
         */
        list_append(&block->free_link, &cache->free_head);
    }
    futex_up(&block->lock);
    futex_up(&cache->lock);
}
 
/** Read data from a block device.
 *
 * @param dev_handle    Device handle of the block device.
 * @param bufpos    Pointer to the first unread valid offset within the
 *          communication buffer.
 * @param buflen    Pointer to the number of unread bytes that are ready in
 *          the communication buffer.
 * @param pos       Device position to be read.
 * @param dst       Destination buffer.
 * @param size      Size of the destination buffer.
 * @param block_size    Block size to be used for the transfer.
 *
 * @return      EOK on success or a negative return code on failure.
 */
int
block_read(dev_handle_t dev_handle, off_t *bufpos, size_t *buflen, off_t *pos,
    void *dst, size_t size, size_t block_size)
{
    off_t offset = 0;
    size_t left = size;
    devcon_t *devcon = devcon_search(dev_handle);
    assert(devcon);
   
    while (left > 0) {
        size_t rd;
       
        if (*bufpos + left < *buflen)
            rd = left;
        else
            rd = *buflen - *bufpos;
       
        if (rd > 0) {
            /*
             * Copy the contents of the communication buffer to the
             * destination buffer.
             */
            memcpy(dst + offset, devcon->com_area + *bufpos, rd);
            offset += rd;
            *bufpos += rd;
            *pos += rd;
            left -= rd;
        }
       
        if (*bufpos == *buflen) {
            /* Refill the communication buffer with a new block. */
            ipcarg_t retval;
            int rc = async_req_2_1(devcon->dev_phone, BD_READ_BLOCK,
                *pos / block_size, block_size, &retval);
            if ((rc != EOK) || (retval != EOK))
                return (rc != EOK ? rc : retval);
           
            *bufpos = 0;
            *buflen = block_size;
        }
    }
   
    return EOK;
}
 
/** @}
 */
 

Rev 4439	Rev 4537
1	/*	1	/*
2	* Copyright (c) 2008 Jakub Jermar	2	* Copyright (c) 2008 Jakub Jermar
3	* Copyright (c) 2008 Martin Decky	3	* Copyright (c) 2008 Martin Decky
4	* All rights reserved.	4	* All rights reserved.
5	*	5	*
6	* Redistribution and use in source and binary forms, with or without	6	* Redistribution and use in source and binary forms, with or without
7	* modification, are permitted provided that the following conditions	7	* modification, are permitted provided that the following conditions
8	* are met:	8	* are met:
9	*	9	*
10	* - Redistributions of source code must retain the above copyright	10	* - Redistributions of source code must retain the above copyright
11	* notice, this list of conditions and the following disclaimer.	11	* notice, this list of conditions and the following disclaimer.
12	* - Redistributions in binary form must reproduce the above copyright	12	* - Redistributions in binary form must reproduce the above copyright
13	* notice, this list of conditions and the following disclaimer in the	13	* notice, this list of conditions and the following disclaimer in the
14	* documentation and/or other materials provided with the distribution.	14	* documentation and/or other materials provided with the distribution.
15	* - The name of the author may not be used to endorse or promote products	15	* - The name of the author may not be used to endorse or promote products
16	* derived from this software without specific prior written permission.	16	* derived from this software without specific prior written permission.
17	*	17	*
18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28	*/	28	*/
29		29
30	/** @addtogroup libblock	30	/** @addtogroup libblock
31	* @{	31	* @{
32	*/	32	*/
33	/**	33	/**
34	* @file	34	* @file
35	* @brief	35	* @brief
36	*/	36	*/
37		37
38	#include "libblock.h"	38	#include "libblock.h"
39	#include "../../srv/vfs/vfs.h"	39	#include "../../srv/vfs/vfs.h"
40	#include <ipc/devmap.h>	40	#include <ipc/devmap.h>
41	#include <ipc/bd.h>	41	#include <ipc/bd.h>
42	#include <ipc/services.h>	42	#include <ipc/services.h>
43	#include <errno.h>	43	#include <errno.h>
44	#include <sys/mman.h>	44	#include <sys/mman.h>
45	#include <async.h>	45	#include <async.h>
46	#include <ipc/ipc.h>	46	#include <ipc/ipc.h>
47	#include <as.h>	47	#include <as.h>
48	#include <assert.h>	48	#include <assert.h>
49	#include <futex.h>	49	#include <futex.h>
50	#include <libadt/list.h>	50	#include <adt/list.h>
51	#include <libadt/hash_table.h>	51	#include <adt/hash_table.h>
-		52	#include <mem.h>
52		53
53	/** Lock protecting the device connection list */	54	/** Lock protecting the device connection list */
54	static futex_t dcl_lock = FUTEX_INITIALIZER;	55	static futex_t dcl_lock = FUTEX_INITIALIZER;
55	/** Device connection list head. */	56	/** Device connection list head. */
56	static LIST_INITIALIZE(dcl_head);	57	static LIST_INITIALIZE(dcl_head);
57		58
58	#define CACHE_BUCKETS_LOG2 10	59	#define CACHE_BUCKETS_LOG2 10
59	#define CACHE_BUCKETS (1 << CACHE_BUCKETS_LOG2)	60	#define CACHE_BUCKETS (1 << CACHE_BUCKETS_LOG2)
60		61
61	typedef struct {	62	typedef struct {
62	futex_t lock;	63	futex_t lock;
63	size_t block_size; /*< Block size. /	64	size_t block_size; /*< Block size. /
64	unsigned block_count; /*< Total number of blocks. /	65	unsigned block_count; /*< Total number of blocks. /
65	hash_table_t block_hash;	66	hash_table_t block_hash;
66	link_t free_head;	67	link_t free_head;
67	} cache_t;	68	} cache_t;
68		69
69	typedef struct {	70	typedef struct {
70	link_t link;	71	link_t link;
71	dev_handle_t dev_handle;	72	dev_handle_t dev_handle;
72	int dev_phone;	73	int dev_phone;
73	void *com_area;	74	void *com_area;
74	size_t com_size;	75	size_t com_size;
75	void *bb_buf;	76	void *bb_buf;
76	off_t bb_off;	77	off_t bb_off;
77	size_t bb_size;	78	size_t bb_size;
78	cache_t *cache;	79	cache_t *cache;
79	} devcon_t;	80	} devcon_t;
80		81
81	static devcon_t *devcon_search(dev_handle_t dev_handle)	82	static devcon_t *devcon_search(dev_handle_t dev_handle)
82	{	83	{
83	link_t *cur;	84	link_t *cur;
84		85
85	futex_down(&dcl_lock);	86	futex_down(&dcl_lock);
86	for (cur = dcl_head.next; cur != &dcl_head; cur = cur->next) {	87	for (cur = dcl_head.next; cur != &dcl_head; cur = cur->next) {
87	devcon_t *devcon = list_get_instance(cur, devcon_t, link);	88	devcon_t *devcon = list_get_instance(cur, devcon_t, link);
88	if (devcon->dev_handle == dev_handle) {	89	if (devcon->dev_handle == dev_handle) {
89	futex_up(&dcl_lock);	90	futex_up(&dcl_lock);
90	return devcon;	91	return devcon;
91	}	92	}
92	}	93	}
93	futex_up(&dcl_lock);	94	futex_up(&dcl_lock);
94	return NULL;	95	return NULL;
95	}	96	}
96		97
97	static int devcon_add(dev_handle_t dev_handle, int dev_phone, void *com_area,	98	static int devcon_add(dev_handle_t dev_handle, int dev_phone, void *com_area,
98	size_t com_size)	99	size_t com_size)
99	{	100	{
100	link_t *cur;	101	link_t *cur;
101	devcon_t *devcon;	102	devcon_t *devcon;
102		103
103	devcon = malloc(sizeof(devcon_t));	104	devcon = malloc(sizeof(devcon_t));
104	if (!devcon)	105	if (!devcon)
105	return ENOMEM;	106	return ENOMEM;
106		107
107	link_initialize(&devcon->link);	108	link_initialize(&devcon->link);
108	devcon->dev_handle = dev_handle;	109	devcon->dev_handle = dev_handle;
109	devcon->dev_phone = dev_phone;	110	devcon->dev_phone = dev_phone;
110	devcon->com_area = com_area;	111	devcon->com_area = com_area;
111	devcon->com_size = com_size;	112	devcon->com_size = com_size;
112	devcon->bb_buf = NULL;	113	devcon->bb_buf = NULL;
113	devcon->bb_off = 0;	114	devcon->bb_off = 0;
114	devcon->bb_size = 0;	115	devcon->bb_size = 0;
115	devcon->cache = NULL;	116	devcon->cache = NULL;
116		117
117	futex_down(&dcl_lock);	118	futex_down(&dcl_lock);
118	for (cur = dcl_head.next; cur != &dcl_head; cur = cur->next) {	119	for (cur = dcl_head.next; cur != &dcl_head; cur = cur->next) {
119	devcon_t *d = list_get_instance(cur, devcon_t, link);	120	devcon_t *d = list_get_instance(cur, devcon_t, link);
120	if (d->dev_handle == dev_handle) {	121	if (d->dev_handle == dev_handle) {
121	futex_up(&dcl_lock);	122	futex_up(&dcl_lock);
122	free(devcon);	123	free(devcon);
123	return EEXIST;	124	return EEXIST;
124	}	125	}
125	}	126	}
126	list_append(&devcon->link, &dcl_head);	127	list_append(&devcon->link, &dcl_head);
127	futex_up(&dcl_lock);	128	futex_up(&dcl_lock);
128	return EOK;	129	return EOK;
129	}	130	}
130		131
131	static void devcon_remove(devcon_t *devcon)	132	static void devcon_remove(devcon_t *devcon)
132	{	133	{
133	futex_down(&dcl_lock);	134	futex_down(&dcl_lock);
134	list_remove(&devcon->link);	135	list_remove(&devcon->link);
135	futex_up(&dcl_lock);	136	futex_up(&dcl_lock);
136	}	137	}
137		138
138	int block_init(dev_handle_t dev_handle, size_t com_size)	139	int block_init(dev_handle_t dev_handle, size_t com_size)
139	{	140	{
140	int rc;	141	int rc;
141	int dev_phone;	142	int dev_phone;
142	void *com_area;	143	void *com_area;
143		144
144	com_area = mmap(NULL, com_size, PROTO_READ \| PROTO_WRITE,	145	com_area = mmap(NULL, com_size, PROTO_READ \| PROTO_WRITE,
145	MAP_ANONYMOUS \| MAP_PRIVATE, 0, 0);	146	MAP_ANONYMOUS \| MAP_PRIVATE, 0, 0);
146	if (!com_area) {	147	if (!com_area) {
147	return ENOMEM;	148	return ENOMEM;
148	}	149	}
149		150
150	dev_phone = devmap_device_connect(dev_handle, IPC_FLAG_BLOCKING);	151	dev_phone = devmap_device_connect(dev_handle, IPC_FLAG_BLOCKING);
151	if (dev_phone < 0) {	152	if (dev_phone < 0) {
152	munmap(com_area, com_size);	153	munmap(com_area, com_size);
153	return dev_phone;	154	return dev_phone;
154	}	155	}
155		156
156	rc = ipc_share_out_start(dev_phone, com_area,	157	rc = ipc_share_out_start(dev_phone, com_area,
157	AS_AREA_READ \| AS_AREA_WRITE);	158	AS_AREA_READ \| AS_AREA_WRITE);
158	if (rc != EOK) {	159	if (rc != EOK) {
159	munmap(com_area, com_size);	160	munmap(com_area, com_size);
160	ipc_hangup(dev_phone);	161	ipc_hangup(dev_phone);
161	return rc;	162	return rc;
162	}	163	}
163		164
164	rc = devcon_add(dev_handle, dev_phone, com_area, com_size);	165	rc = devcon_add(dev_handle, dev_phone, com_area, com_size);
165	if (rc != EOK) {	166	if (rc != EOK) {
166	munmap(com_area, com_size);	167	munmap(com_area, com_size);
167	ipc_hangup(dev_phone);	168	ipc_hangup(dev_phone);
168	return rc;	169	return rc;
169	}	170	}
170		171
171	return EOK;	172	return EOK;
172	}	173	}
173		174
174	void block_fini(dev_handle_t dev_handle)	175	void block_fini(dev_handle_t dev_handle)
175	{	176	{
176	devcon_t *devcon = devcon_search(dev_handle);	177	devcon_t *devcon = devcon_search(dev_handle);
177	assert(devcon);	178	assert(devcon);
178		179
179	devcon_remove(devcon);	180	devcon_remove(devcon);
180		181
181	if (devcon->bb_buf)	182	if (devcon->bb_buf)
182	free(devcon->bb_buf);	183	free(devcon->bb_buf);
183		184
184	if (devcon->cache) {	185	if (devcon->cache) {
185	hash_table_destroy(&devcon->cache->block_hash);	186	hash_table_destroy(&devcon->cache->block_hash);
186	free(devcon->cache);	187	free(devcon->cache);
187	}	188	}
188		189
189	munmap(devcon->com_area, devcon->com_size);	190	munmap(devcon->com_area, devcon->com_size);
190	ipc_hangup(devcon->dev_phone);	191	ipc_hangup(devcon->dev_phone);
191		192
192	free(devcon);	193	free(devcon);
193	}	194	}
194		195
195	int block_bb_read(dev_handle_t dev_handle, off_t off, size_t size)	196	int block_bb_read(dev_handle_t dev_handle, off_t off, size_t size)
196	{	197	{
197	void *bb_buf;	198	void *bb_buf;
198	int rc;	199	int rc;
199		200
200	devcon_t *devcon = devcon_search(dev_handle);	201	devcon_t *devcon = devcon_search(dev_handle);
201	if (!devcon)	202	if (!devcon)
202	return ENOENT;	203	return ENOENT;
203	if (devcon->bb_buf)	204	if (devcon->bb_buf)
204	return EEXIST;	205	return EEXIST;
205	bb_buf = malloc(size);	206	bb_buf = malloc(size);
206	if (!bb_buf)	207	if (!bb_buf)
207	return ENOMEM;	208	return ENOMEM;
208		209
209	off_t bufpos = 0;	210	off_t bufpos = 0;
210	size_t buflen = 0;	211	size_t buflen = 0;
211	rc = block_read(dev_handle, &bufpos, &buflen, &off,	212	rc = block_read(dev_handle, &bufpos, &buflen, &off,
212	bb_buf, size, size);	213	bb_buf, size, size);
213	if (rc != EOK) {	214	if (rc != EOK) {
214	free(bb_buf);	215	free(bb_buf);
215	return rc;	216	return rc;
216	}	217	}
217	devcon->bb_buf = bb_buf;	218	devcon->bb_buf = bb_buf;
218	devcon->bb_off = off;	219	devcon->bb_off = off;
219	devcon->bb_size = size;	220	devcon->bb_size = size;
220		221
221	return EOK;	222	return EOK;
222	}	223	}
223		224
224	void *block_bb_get(dev_handle_t dev_handle)	225	void *block_bb_get(dev_handle_t dev_handle)
225	{	226	{
226	devcon_t *devcon = devcon_search(dev_handle);	227	devcon_t *devcon = devcon_search(dev_handle);
227	assert(devcon);	228	assert(devcon);
228	return devcon->bb_buf;	229	return devcon->bb_buf;
229	}	230	}
230		231
231	static hash_index_t cache_hash(unsigned long *key)	232	static hash_index_t cache_hash(unsigned long *key)
232	{	233	{
233	return *key & (CACHE_BUCKETS - 1);	234	return *key & (CACHE_BUCKETS - 1);
234	}	235	}
235		236
236	static int cache_compare(unsigned long key, hash_count_t keys, link_t item)	237	static int cache_compare(unsigned long key, hash_count_t keys, link_t item)
237	{	238	{
238	block_t *b = hash_table_get_instance(item, block_t, hash_link);	239	block_t *b = hash_table_get_instance(item, block_t, hash_link);
239	return b->boff == *key;	240	return b->boff == *key;
240	}	241	}
241		242
242	static void cache_remove_callback(link_t *item)	243	static void cache_remove_callback(link_t *item)
243	{	244	{
244	}	245	}
245		246
246	static hash_table_operations_t cache_ops = {	247	static hash_table_operations_t cache_ops = {
247	.hash = cache_hash,	248	.hash = cache_hash,
248	.compare = cache_compare,	249	.compare = cache_compare,
249	.remove_callback = cache_remove_callback	250	.remove_callback = cache_remove_callback
250	};	251	};
251		252
252	int block_cache_init(dev_handle_t dev_handle, size_t size, unsigned blocks)	253	int block_cache_init(dev_handle_t dev_handle, size_t size, unsigned blocks)
253	{	254	{
254	devcon_t *devcon = devcon_search(dev_handle);	255	devcon_t *devcon = devcon_search(dev_handle);
255	cache_t *cache;	256	cache_t *cache;
256	if (!devcon)	257	if (!devcon)
257	return ENOENT;	258	return ENOENT;
258	if (devcon->cache)	259	if (devcon->cache)
259	return EEXIST;	260	return EEXIST;
260	cache = malloc(sizeof(cache_t));	261	cache = malloc(sizeof(cache_t));
261	if (!cache)	262	if (!cache)
262	return ENOMEM;	263	return ENOMEM;
263		264
264	futex_initialize(&cache->lock, 1);	265	futex_initialize(&cache->lock, 1);
265	list_initialize(&cache->free_head);	266	list_initialize(&cache->free_head);
266	cache->block_size = size;	267	cache->block_size = size;
267	cache->block_count = blocks;	268	cache->block_count = blocks;
268		269
269	if (!hash_table_create(&cache->block_hash, CACHE_BUCKETS, 1,	270	if (!hash_table_create(&cache->block_hash, CACHE_BUCKETS, 1,
270	&cache_ops)) {	271	&cache_ops)) {
271	free(cache);	272	free(cache);
272	return ENOMEM;	273	return ENOMEM;
273	}	274	}
274		275
275	devcon->cache = cache;	276	devcon->cache = cache;
276	return EOK;	277	return EOK;
277	}	278	}
278		279
279	static bool cache_can_grow(cache_t *cache)	280	static bool cache_can_grow(cache_t *cache)
280	{	281	{
281	return true;	282	return true;
282	}	283	}
283		284
284	static void block_initialize(block_t *b)	285	static void block_initialize(block_t *b)
285	{	286	{
286	futex_initialize(&b->lock, 1);	287	futex_initialize(&b->lock, 1);
287	b->refcnt = 1;	288	b->refcnt = 1;
288	b->dirty = false;	289	b->dirty = false;
289	rwlock_initialize(&b->contents_lock);	290	rwlock_initialize(&b->contents_lock);
290	link_initialize(&b->free_link);	291	link_initialize(&b->free_link);
291	link_initialize(&b->hash_link);	292	link_initialize(&b->hash_link);
292	}	293	}
293		294
294	/** Instantiate a block in memory and get a reference to it.	295	/** Instantiate a block in memory and get a reference to it.
295	*	296	*
296	* @param dev_handle Device handle of the block device.	297	* @param dev_handle Device handle of the block device.
297	* @param boff Block offset.	298	* @param boff Block offset.
298	* @param flags If BLOCK_FLAGS_NOREAD is specified, block_get()	299	* @param flags If BLOCK_FLAGS_NOREAD is specified, block_get()
299	* will not read the contents of the block from the	300	* will not read the contents of the block from the
300	* device.	301	* device.
301	*	302	*
302	* @return Block structure.	303	* @return Block structure.
303	*/	304	*/
304	block_t *block_get(dev_handle_t dev_handle, bn_t boff, int flags)	305	block_t *block_get(dev_handle_t dev_handle, bn_t boff, int flags)
305	{	306	{
306	devcon_t *devcon;	307	devcon_t *devcon;
307	cache_t *cache;	308	cache_t *cache;
308	block_t *b;	309	block_t *b;
309	link_t *l;	310	link_t *l;
310	unsigned long key = boff;	311	unsigned long key = boff;
311		312
312	devcon = devcon_search(dev_handle);	313	devcon = devcon_search(dev_handle);
313		314
314	assert(devcon);	315	assert(devcon);
315	assert(devcon->cache);	316	assert(devcon->cache);
316		317
317	cache = devcon->cache;	318	cache = devcon->cache;
318	futex_down(&cache->lock);	319	futex_down(&cache->lock);
319	l = hash_table_find(&cache->block_hash, &key);	320	l = hash_table_find(&cache->block_hash, &key);
320	if (l) {	321	if (l) {
321	/*	322	/*
322	* We found the block in the cache.	323	* We found the block in the cache.
323	*/	324	*/
324	b = hash_table_get_instance(l, block_t, hash_link);	325	b = hash_table_get_instance(l, block_t, hash_link);
325	futex_down(&b->lock);	326	futex_down(&b->lock);
326	if (b->refcnt++ == 0)	327	if (b->refcnt++ == 0)
327	list_remove(&b->free_link);	328	list_remove(&b->free_link);
328	futex_up(&b->lock);	329	futex_up(&b->lock);
329	futex_up(&cache->lock);	330	futex_up(&cache->lock);
330	} else {	331	} else {
331	/*	332	/*
332	* The block was not found in the cache.	333	* The block was not found in the cache.
333	*/	334	*/
334	int rc;	335	int rc;
335	off_t bufpos = 0;	336	off_t bufpos = 0;
336	size_t buflen = 0;	337	size_t buflen = 0;
337	off_t pos = boff * cache->block_size;	338	off_t pos = boff * cache->block_size;
338	bool sync = false;	339	bool sync = false;
339		340
340	if (cache_can_grow(cache)) {	341	if (cache_can_grow(cache)) {
341	/*	342	/*
342	* We can grow the cache by allocating new blocks.	343	* We can grow the cache by allocating new blocks.
343	* Should the allocation fail, we fail over and try to	344	* Should the allocation fail, we fail over and try to
344	* recycle a block from the cache.	345	* recycle a block from the cache.
345	*/	346	*/
346	b = malloc(sizeof(block_t));	347	b = malloc(sizeof(block_t));
347	if (!b)	348	if (!b)
348	goto recycle;	349	goto recycle;
349	b->data = malloc(cache->block_size);	350	b->data = malloc(cache->block_size);
350	if (!b->data) {	351	if (!b->data) {
351	free(b);	352	free(b);
352	goto recycle;	353	goto recycle;
353	}	354	}
354	} else {	355	} else {
355	/*	356	/*
356	* Try to recycle a block from the free list.	357	* Try to recycle a block from the free list.
357	*/	358	*/
358	unsigned long temp_key;	359	unsigned long temp_key;
359	recycle:	360	recycle:
360	assert(!list_empty(&cache->free_head));	361	assert(!list_empty(&cache->free_head));
361	l = cache->free_head.next;	362	l = cache->free_head.next;
362	list_remove(l);	363	list_remove(l);
363	b = hash_table_get_instance(l, block_t, hash_link);	364	b = hash_table_get_instance(l, block_t, hash_link);
364	sync = b->dirty;	365	sync = b->dirty;
365	temp_key = b->boff;	366	temp_key = b->boff;
366	hash_table_remove(&cache->block_hash, &temp_key, 1);	367	hash_table_remove(&cache->block_hash, &temp_key, 1);
367	}	368	}
368		369
369	block_initialize(b);	370	block_initialize(b);
370	b->dev_handle = dev_handle;	371	b->dev_handle = dev_handle;
371	b->size = cache->block_size;	372	b->size = cache->block_size;
372	b->boff = boff;	373	b->boff = boff;
373	hash_table_insert(&cache->block_hash, &key, &b->hash_link);	374	hash_table_insert(&cache->block_hash, &key, &b->hash_link);
374		375
375	/*	376	/*
376	* Lock the block before releasing the cache lock. Thus we don't	377	* Lock the block before releasing the cache lock. Thus we don't
377	* kill concurent operations on the cache while doing I/O on the	378	* kill concurent operations on the cache while doing I/O on the
378	* block.	379	* block.
379	*/	380	*/
380	futex_down(&b->lock);	381	futex_down(&b->lock);
381	futex_up(&cache->lock);	382	futex_up(&cache->lock);
382		383
383	if (sync) {	384	if (sync) {
384	/*	385	/*
385	* The block is dirty and needs to be written back to	386	* The block is dirty and needs to be written back to
386	* the device before we can read in the new contents.	387	* the device before we can read in the new contents.
387	*/	388	*/
388	abort(); /* TODO: block_write() */	389	abort(); /* TODO: block_write() */
389	}	390	}
390	if (!(flags & BLOCK_FLAGS_NOREAD)) {	391	if (!(flags & BLOCK_FLAGS_NOREAD)) {
391	/*	392	/*
392	* The block contains old or no data. We need to read	393	* The block contains old or no data. We need to read
393	* the new contents from the device.	394	* the new contents from the device.
394	*/	395	*/
395	rc = block_read(dev_handle, &bufpos, &buflen, &pos,	396	rc = block_read(dev_handle, &bufpos, &buflen, &pos,
396	b->data, cache->block_size, cache->block_size);	397	b->data, cache->block_size, cache->block_size);
397	assert(rc == EOK);	398	assert(rc == EOK);
398	}	399	}
399		400
400	futex_up(&b->lock);	401	futex_up(&b->lock);
401	}	402	}
402	return b;	403	return b;
403	}	404	}
404		405
405	/** Release a reference to a block.	406	/** Release a reference to a block.
406	*	407	*
407	* If the last reference is dropped, the block is put on the free list.	408	* If the last reference is dropped, the block is put on the free list.
408	*	409	*
409	* @param block Block of which a reference is to be released.	410	* @param block Block of which a reference is to be released.
410	*/	411	*/
411	void block_put(block_t *block)	412	void block_put(block_t *block)
412	{	413	{
413	devcon_t *devcon = devcon_search(block->dev_handle);	414	devcon_t *devcon = devcon_search(block->dev_handle);
414	cache_t *cache;	415	cache_t *cache;
415		416
416	assert(devcon);	417	assert(devcon);
417	assert(devcon->cache);	418	assert(devcon->cache);
418		419
419	cache = devcon->cache;	420	cache = devcon->cache;
420	futex_down(&cache->lock);	421	futex_down(&cache->lock);
421	futex_down(&block->lock);	422	futex_down(&block->lock);
422	if (!--block->refcnt) {	423	if (!--block->refcnt) {
423	/*	424	/*
424	* Last reference to the block was dropped, put the block on the	425	* Last reference to the block was dropped, put the block on the
425	* free list.	426	* free list.
426	*/	427	*/
427	list_append(&block->free_link, &cache->free_head);	428	list_append(&block->free_link, &cache->free_head);
428	}	429	}
429	futex_up(&block->lock);	430	futex_up(&block->lock);
430	futex_up(&cache->lock);	431	futex_up(&cache->lock);
431	}	432	}
432		433
433	/** Read data from a block device.	434	/** Read data from a block device.
434	*	435	*
435	* @param dev_handle Device handle of the block device.	436	* @param dev_handle Device handle of the block device.
436	* @param bufpos Pointer to the first unread valid offset within the	437	* @param bufpos Pointer to the first unread valid offset within the
437	* communication buffer.	438	* communication buffer.
438	* @param buflen Pointer to the number of unread bytes that are ready in	439	* @param buflen Pointer to the number of unread bytes that are ready in
439	* the communication buffer.	440	* the communication buffer.
440	* @param pos Device position to be read.	441	* @param pos Device position to be read.
441	* @param dst Destination buffer.	442	* @param dst Destination buffer.
442	* @param size Size of the destination buffer.	443	* @param size Size of the destination buffer.
443	* @param block_size Block size to be used for the transfer.	444	* @param block_size Block size to be used for the transfer.
444	*	445	*
445	* @return EOK on success or a negative return code on failure.	446	* @return EOK on success or a negative return code on failure.
446	*/	447	*/
447	int	448	int
448	block_read(dev_handle_t dev_handle, off_t bufpos, size_t buflen, off_t *pos,	449	block_read(dev_handle_t dev_handle, off_t bufpos, size_t buflen, off_t *pos,
449	void *dst, size_t size, size_t block_size)	450	void *dst, size_t size, size_t block_size)
450	{	451	{
451	off_t offset = 0;	452	off_t offset = 0;
452	size_t left = size;	453	size_t left = size;
453	devcon_t *devcon = devcon_search(dev_handle);	454	devcon_t *devcon = devcon_search(dev_handle);
454	assert(devcon);	455	assert(devcon);
455		456
456	while (left > 0) {	457	while (left > 0) {
457	size_t rd;	458	size_t rd;
458		459
459	if (bufpos + left < buflen)	460	if (bufpos + left < buflen)
460	rd = left;	461	rd = left;
461	else	462	else
462	rd = buflen - bufpos;	463	rd = buflen - bufpos;
463		464
464	if (rd > 0) {	465	if (rd > 0) {
465	/*	466	/*
466	* Copy the contents of the communication buffer to the	467	* Copy the contents of the communication buffer to the
467	* destination buffer.	468	* destination buffer.
468	*/	469	*/
469	memcpy(dst + offset, devcon->com_area + *bufpos, rd);	470	memcpy(dst + offset, devcon->com_area + *bufpos, rd);
470	offset += rd;	471	offset += rd;
471	*bufpos += rd;	472	*bufpos += rd;
472	*pos += rd;	473	*pos += rd;
473	left -= rd;	474	left -= rd;
474	}	475	}
475		476
476	if (bufpos == buflen) {	477	if (bufpos == buflen) {
477	/* Refill the communication buffer with a new block. */	478	/* Refill the communication buffer with a new block. */
478	ipcarg_t retval;	479	ipcarg_t retval;
479	int rc = async_req_2_1(devcon->dev_phone, BD_READ_BLOCK,	480	int rc = async_req_2_1(devcon->dev_phone, BD_READ_BLOCK,
480	*pos / block_size, block_size, &retval);	481	*pos / block_size, block_size, &retval);
481	if ((rc != EOK) \|\| (retval != EOK))	482	if ((rc != EOK) \|\| (retval != EOK))
482	return (rc != EOK ? rc : retval);	483	return (rc != EOK ? rc : retval);
483		484
484	*bufpos = 0;	485	*bufpos = 0;
485	*buflen = block_size;	486	*buflen = block_size;
486	}	487	}
487	}	488	}
488		489
489	return EOK;	490	return EOK;
490	}	491	}
491		492
492	/** @}	493	/** @}
493	*/	494	*/
494		495

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(root)/branches/dd/uspace/lib/libblock/libblock.c – Rev 4439 → 4537