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 * during allocation of clusters. The lock does not have to be held durring
 51 
 * during allocation of clusters. The lock does not have to be held durring
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 * deallocation of clusters.
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 * deallocation of clusters.
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 */  
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 */  
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static futex_t fat_alloc_lock = FUTEX_INITIALIZER;
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static futex_t fat_alloc_lock = FUTEX_INITIALIZER;
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 55 
 
- 
 
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/** Read block from file located on a FAT file system.
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 *
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 * @param bs        Buffer holding the boot sector of the file system.
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 * @param dev_handle    Device handle of the file system.
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 * @param firstc    First cluster used by the file. Can be zero if the file
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 *          is empty.
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 * @param offset    Offset in blocks.
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 *
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 * @return      Block structure holding the requested block.
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 */
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block_t *
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block_t *
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_fat_block_get(fat_bs_t *bs, dev_handle_t dev_handle, fat_cluster_t firstc,
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_fat_block_get(fat_bs_t *bs, dev_handle_t dev_handle, fat_cluster_t firstc,
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    off_t offset)
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    off_t offset)
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{
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{
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    block_t *b;
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    block_t *b;
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        b->dirty = true;        /* need to sync node */
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        b->dirty = true;        /* need to sync node */
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        block_put(b);
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        block_put(b);
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    }
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    }
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}
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}
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/** Mark cluster in one instance of FAT.
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 *
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 * @param bs        Buffer holding the boot sector for the file system.
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 * @param dev_handle    Device handle for the file system.
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 * @param fatno     Number of the FAT instance where to make the change.
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 * @param clst      Cluster which is to be marked.
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 * @param value     Value mark the cluster with.
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 */
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void
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void
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fat_mark_cluster(fat_bs_t *bs, dev_handle_t dev_handle, unsigned fatno,
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fat_mark_cluster(fat_bs_t *bs, dev_handle_t dev_handle, unsigned fatno,
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    fat_cluster_t clst, fat_cluster_t value)
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    fat_cluster_t clst, fat_cluster_t value)
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{
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{
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    block_t *b;
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    block_t *b;
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    *cp = host2uint16_t_le(value);
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    *cp = host2uint16_t_le(value);
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    b->dirty = true;        /* need to sync block */
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    b->dirty = true;        /* need to sync block */
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    block_put(b);
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    block_put(b);
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}
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}
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/** Replay the allocatoin of clusters in all shadow instances of FAT.
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 *
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 * @param bs        Buffer holding the boot sector of the file system.
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 * @param dev_handle    Device handle of the file system.
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 * @param lifo      Chain of allocated clusters.
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 * @param nclsts    Number of clusters in the lifo chain.
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 */
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void fat_alloc_shadow_clusters(fat_bs_t *bs, dev_handle_t dev_handle,
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void fat_alloc_shadow_clusters(fat_bs_t *bs, dev_handle_t dev_handle,
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    fat_cluster_t *lifo, unsigned nclsts)
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    fat_cluster_t *lifo, unsigned nclsts)
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{
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{
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    uint8_t fatno;
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    uint8_t fatno;
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    unsigned c;
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    unsigned c;
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                c == 0 ? FAT_CLST_LAST1 : lifo[c - 1]);
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                c == 0 ? FAT_CLST_LAST1 : lifo[c - 1]);
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        }
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        }
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    }
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    }
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}
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}
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/** Allocate clusters in FAT1.
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 *
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 * This function will attempt to allocate the requested number of clusters in
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 * the first FAT instance.  The FAT will be altered so that the allocated
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 * clusters form an independent chain (i.e. a chain which does not belong to any
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 * file yet).
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 *
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 * @param bs        Buffer holding the boot sector of the file system.
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 * @param dev_handle    Device handle of the file system.
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 * @param nclsts    Number of clusters to allocate.
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 * @param mcl       Output parameter where the first cluster in the chain
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 *          will be returned.
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 * @param lcl       Output parameter where the last cluster in the chain
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 *          will be returned.
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 *
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 * @return      EOK on success, a negative error code otherwise.
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 */
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int
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int
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fat_alloc_clusters(fat_bs_t *bs, dev_handle_t dev_handle, unsigned nclsts,
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fat_alloc_clusters(fat_bs_t *bs, dev_handle_t dev_handle, unsigned nclsts,
250 
    fat_cluster_t *mcl, fat_cluster_t *lcl)
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    fat_cluster_t *mcl, fat_cluster_t *lcl)
251 
{
 293 
{
252 
    uint16_t bps;
 294 
    uint16_t bps;
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 354 
   
313 
    free(lifo);
 355 
    free(lifo);
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    return ENOSPC;
 356 
    return ENOSPC;
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}
 357 
}
316 
 
 358 
 
- 
 
 359 
/** Append a cluster chain to the last file cluster in all FATs.
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 360 
 *
- 
 
 361 
 * @param bs        Buffer holding boot sector of the file system.
- 
 
 362 
 * @param nodep     Node representing the file.
- 
 
 363 
 * @param mcl       First cluster of the cluster chain to append.
- 
 
 364 
 */
317 
void fat_append_clusters(fat_bs_t *bs, fat_node_t *nodep, fat_cluster_t mcl)
 365 
void fat_append_clusters(fat_bs_t *bs, fat_node_t *nodep, fat_cluster_t mcl)
318 
{
 366 
{
319 
    dev_handle_t dev_handle = nodep->idx->dev_handle;
 367 
    dev_handle_t dev_handle = nodep->idx->dev_handle;
320 
    fat_cluster_t lcl;
 368 
    fat_cluster_t lcl;
321 
    uint8_t fatno;
 369 
    uint8_t fatno;