bd3cde4571
Add primary cache management feature to libminixfs as mfs and ext2
currently do separately, remove cache code from mfs and ext2, and make
them use the libminixfs interface. This makes all fields of the buf
struct private to libminixfs and FS clients aren't supposed to access
them at all. Only the opaque 'void *data' field (the FS block contents,
used to be called bp) is to be accessed by the FS client.
The main purpose is to implement the interface to the 2ndary vm cache
just once, get rid of some code duplication, and add a little
abstraction to reduce the code inertia of the whole caching business.
Some minor sanity checking and prohibition done by mfs in this code
as removed from the generic primary cache code as a result:
- checking all inodes are not in use when allocating/resizing
the cache
- checking readonly filesystems aren't written to
- checking the superblock isn't written to on mounted filesystems
The minixfslib code relies on fs_blockstats() in the client filesystem to
return some FS usage information.
72 lines
2.8 KiB
C
72 lines
2.8 KiB
C
/* Prototypes for -lminixfs. */
|
|
|
|
#ifndef _MINIX_FSLIB_H
|
|
#define _MINIX_FSLIB_H
|
|
|
|
#include <minix/safecopies.h>
|
|
#include <minix/sef.h>
|
|
#include <minix/vfsif.h>
|
|
|
|
struct buf {
|
|
/* Data portion of the buffer. */
|
|
void *data;
|
|
|
|
/* Header portion of the buffer - internal to libminixfs. */
|
|
struct buf *lmfs_next; /* used to link all free bufs in a chain */
|
|
struct buf *lmfs_prev; /* used to link all free bufs the other way */
|
|
struct buf *lmfs_hash; /* used to link bufs on hash chains */
|
|
block_t lmfs_blocknr; /* block number of its (minor) device */
|
|
dev_t lmfs_dev; /* major | minor device where block resides */
|
|
char lmfs_dirt; /* BP_CLEAN or BP_DIRTY */
|
|
char lmfs_count; /* number of users of this buffer */
|
|
unsigned int lmfs_bytes; /* Number of bytes allocated in bp */
|
|
};
|
|
|
|
int fs_lookup_credentials(vfs_ucred_t *credentials,
|
|
uid_t *caller_uid, gid_t *caller_gid, cp_grant_id_t grant2, size_t cred_size);
|
|
u32_t fs_bufs_heuristic(int minbufs, u32_t btotal, u32_t bfree,
|
|
int blocksize, dev_t majordev);
|
|
|
|
void lmfs_markdirty(struct buf *bp);
|
|
void lmfs_markclean(struct buf *bp);
|
|
int lmfs_isclean(struct buf *bp);
|
|
dev_t lmfs_dev(struct buf *bp);
|
|
int lmfs_bytes(struct buf *bp);
|
|
int lmfs_bufs_in_use(void);
|
|
int lmfs_nr_bufs(void);
|
|
void lmfs_flushall(void);
|
|
int lmfs_fs_block_size(void);
|
|
void lmfs_may_use_vmcache(int);
|
|
void lmfs_set_blocksize(int blocksize, int major);
|
|
void lmfs_reset_rdwt_err(void);
|
|
int lmfs_rdwt_err(void);
|
|
void lmfs_buf_pool(int new_nr_bufs);
|
|
struct buf *lmfs_get_block(dev_t dev, block_t block,int only_search);
|
|
void lmfs_invalidate(dev_t device);
|
|
void lmfs_put_block(struct buf *bp, int block_type);
|
|
void lmfs_rw_scattered(dev_t, struct buf **, int, int);
|
|
|
|
/* calls that libminixfs does into fs */
|
|
void fs_blockstats(u32_t *blocks, u32_t *free, u32_t *used);
|
|
int fs_sync(void);
|
|
|
|
/* get_block arguments */
|
|
#define NORMAL 0 /* forces get_block to do disk read */
|
|
#define NO_READ 1 /* prevents get_block from doing disk read */
|
|
#define PREFETCH 2 /* tells get_block not to read or mark dev */
|
|
|
|
/* When a block is released, the type of usage is passed to put_block(). */
|
|
#define ONE_SHOT 0200 /* set if block not likely to be needed soon */
|
|
|
|
#define INODE_BLOCK 0 /* inode block */
|
|
#define DIRECTORY_BLOCK 1 /* directory block */
|
|
#define INDIRECT_BLOCK 2 /* pointer block */
|
|
#define MAP_BLOCK 3 /* bit map */
|
|
#define FULL_DATA_BLOCK 5 /* data, fully used */
|
|
#define PARTIAL_DATA_BLOCK 6 /* data, partly used*/
|
|
|
|
#define END_OF_FILE (-104) /* eof detected */
|
|
|
|
#endif /* _MINIX_FSLIB_H */
|
|
|