blkcache.h File Reference

#include <core/system.h>

Go to the source code of this file.

Typedefs
typedef ssize_t(*)	blkcache_io(void *owner, uint64_t sector, size_t count, void *buf)

Functions
ssize_t	blkcache_read (void *owner, uint64_t sector, size_t count, void *buf, uint64_t nsectors, blkcache_io read)
	Reads sectors of a disk through the cache.
ssize_t	blkcache_write (void *owner, uint64_t sector, size_t count, void *buf, blkcache_io write)
	Writes sectors of a disk through the cache: they stay dirty in it until it is flushed.
int	blkcache_flush (void)
	Writes every dirty block of the cache to its disk.

Typedef Documentation

blkcache_io

typedef ssize_t(*) blkcache_io(void *owner, uint64_t sector, size_t count, void *buf)

Definition at line 10 of file blkcache.h.

Function Documentation

blkcache_flush()

int blkcache_flush

(

void

)

Writes every dirty block of the cache to its disk.

Returns

0, or a negative errno if a write failed

Definition at line 309 of file blkcache.c.

References blkcache_flush(), blks, CACHE_BLOCKS, blk::dirty, dirty, flush_block(), full_dirty(), lookup(), blk::nr, blk::owner, RUN_MAX, and blk::write.

Referenced by blkcache_flush(), blkcache_write(), flush_old(), and kdev_sync().

blkcache_read()

ssize_t blkcache_read	(	void *	owner,
		uint64_t	sector,
		size_t	count,
		void *	buf,
		uint64_t	nsectors,
		blkcache_io	read )

Reads sectors of a disk through the cache.

The sectors the cache doesn't have are read with read, and cached.

Parameters

owner	the disk (the driver's, for its sectors)
sector	the first sector, absolute on the disk
count	how many sectors
buf	where to put them
nsectors	the disk's size in sectors, or 0 if it isn't known
read	how the driver reads sectors

Returns

0, or a negative errno (-EIO past the disk's end)

Definition at line 367 of file blkcache.c.

References blk_data(), BLK_SECTORS, BLK_SIZE, blkcache_read(), block_new(), flush_old(), kfree(), kmalloc(), lookup(), memcpy(), MIN, blk::nr, overlap(), blk::owner, prefault(), RUN_MAX, sector_mask(), SECTOR_SIZE, touch(), blk::valid, and writes.

Referenced by ata_read(), and blkcache_read().

blkcache_write()

ssize_t blkcache_write	(	void *	owner,
		uint64_t	sector,
		size_t	count,
		void *	buf,
		blkcache_io	write )

Writes sectors of a disk through the cache: they stay dirty in it until it is flushed.

If the cache has no room even after flushing, they go straight to the disk.

Parameters

owner	the disk (the driver's, for its sectors)
sector	the first sector, absolute on the disk
count	how many sectors
buf	the sectors' data
write	how the driver writes sectors

Returns

0, or a negative errno

Definition at line 484 of file blkcache.c.

References blk_data(), BLK_SECTORS, blkcache_flush(), blkcache_write(), block_new(), dirty, DIRTY_MAX, flush_old(), kfree(), kmalloc(), lookup(), make_dirty(), memcpy(), blk::nr, overlap(), blk::owner, prefault(), sector_mask(), SECTOR_SIZE, touch(), blk::valid, blk::write, and writes.

Referenced by ata_write(), and blkcache_write().