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Ignore whitespace Rev 3560 → Rev 3561

/branches/dynload/uspace/lib/libblock/libblock.c
48,6 → 48,7
#include <assert.h>
#include <futex.h>
#include <libadt/list.h>
#include <libadt/hash_table.h>
 
/** Lock protecting the device connection list */
static futex_t dcl_lock = FUTEX_INITIALIZER;
54,7 → 55,18
/** 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;
int dev_handle;
int dev_phone;
63,6 → 75,7
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)
82,7 → 95,7
}
 
static int devcon_add(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)
size_t com_size)
{
link_t *cur;
devcon_t *devcon;
96,9 → 109,10
devcon->dev_phone = dev_phone;
devcon->com_area = com_area;
devcon->com_size = com_size;
devcon->bb_buf = bb_buf;
devcon->bb_off = bb_off;
devcon->bb_size = bb_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) {
121,23 → 135,15
futex_up(&dcl_lock);
}
 
int
block_init(dev_handle_t dev_handle, size_t com_size, off_t bb_off,
size_t bb_size)
int block_init(dev_handle_t dev_handle, size_t com_size)
{
int rc;
int dev_phone;
void *com_area;
void *bb_buf;
bb_buf = malloc(bb_size);
if (!bb_buf)
return ENOMEM;
com_area = mmap(NULL, com_size, PROTO_READ | PROTO_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
if (!com_area) {
free(bb_buf);
return ENOMEM;
}
dev_phone = ipc_connect_me_to(PHONE_NS, SERVICE_DEVMAP,
144,7 → 150,6
DEVMAP_CONNECT_TO_DEVICE, dev_handle);
 
if (dev_phone < 0) {
free(bb_buf);
munmap(com_area, com_size);
return dev_phone;
}
152,29 → 157,18
rc = ipc_share_out_start(dev_phone, com_area,
AS_AREA_READ | AS_AREA_WRITE);
if (rc != EOK) {
free(bb_buf);
munmap(com_area, com_size);
ipc_hangup(dev_phone);
return rc;
}
rc = devcon_add(dev_handle, dev_phone, com_area, com_size, bb_buf,
bb_off, bb_size);
rc = devcon_add(dev_handle, dev_phone, com_area, com_size);
if (rc != EOK) {
free(bb_buf);
munmap(com_area, com_size);
ipc_hangup(dev_phone);
return rc;
}
 
off_t bufpos = 0;
size_t buflen = 0;
if (!block_read(dev_handle, &bufpos, &buflen, &bb_off,
bb_buf, bb_size, bb_size)) {
block_fini(dev_handle);
return EIO; /* XXX real error code */
}
return EOK;
}
 
185,7 → 179,14
devcon_remove(devcon);
 
free(devcon->bb_buf);
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);
 
192,6 → 193,35
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);
199,6 → 229,203
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.
*
* @return Block structure.
*/
block_t *block_get(dev_handle_t dev_handle, off_t boff)
{
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() */
}
/*
* 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.
211,9 → 438,9
* @param size Size of the destination buffer.
* @param block_size Block size to be used for the transfer.
*
* @return True on success, false on failure.
* @return EOK on success or a negative return code on failure.
*/
bool
int
block_read(int dev_handle, off_t *bufpos, size_t *buflen, off_t *pos, void *dst,
size_t size, size_t block_size)
{
248,7 → 475,7
int rc = async_req_2_1(devcon->dev_phone, RD_READ_BLOCK,
*pos / block_size, block_size, &retval);
if ((rc != EOK) || (retval != EOK))
return false;
return (rc != EOK ? rc : retval);
*bufpos = 0;
*buflen = block_size;
255,44 → 482,8
}
}
return true;
return EOK;
}
 
block_t *block_get(dev_handle_t dev_handle, off_t offset, size_t bs)
{
/* FIXME */
block_t *b;
off_t bufpos = 0;
size_t buflen = 0;
off_t pos = offset * bs;
 
b = malloc(sizeof(block_t));
if (!b)
return NULL;
b->data = malloc(bs);
if (!b->data) {
free(b);
return NULL;
}
b->size = bs;
 
if (!block_read(dev_handle, &bufpos, &buflen, &pos, b->data,
bs, bs)) {
free(b->data);
free(b);
return NULL;
}
 
return b;
}
 
void block_put(block_t *block)
{
/* FIXME */
free(block->data);
free(block);
}
 
/** @}
*/
/branches/dynload/uspace/lib/libblock/libblock.h
67,14 → 67,18
void *data;
} block_t;
 
extern int block_init(dev_handle_t, size_t, off_t, size_t);
extern int block_init(dev_handle_t, size_t);
extern void block_fini(dev_handle_t);
 
extern int block_bb_read(dev_handle_t, off_t, size_t);
extern void *block_bb_get(dev_handle_t);
 
extern block_t *block_get(dev_handle_t, off_t, size_t);
extern int block_cache_init(dev_handle_t, size_t, unsigned);
 
extern block_t *block_get(dev_handle_t, off_t);
extern void block_put(block_t *);
 
extern bool block_read(int, off_t *, size_t *, off_t *, void *, size_t, size_t);
extern int block_read(int, off_t *, size_t *, off_t *, void *, size_t, size_t);
 
#endif