diff options
Diffstat (limited to 'eio.h')
| -rw-r--r-- | eio.h | 173 |
1 files changed, 173 insertions, 0 deletions
@@ -0,0 +1,173 @@ +#ifndef EIO_H_ +#define EIO_H_ + +#include <stddef.h> +#include <stdlib.h> + +typedef struct eio_req eio_req; + +typedef int (*eio_cb)(eio_req *req); + +#ifndef EIO_COMMON +# define EIO_COMMON \ + eio_cb finish; \ + void (*destroy)(eio_req *req);\ + void *data +#endif + +enum { + EIO_QUIT, + EIO_OPEN, EIO_CLOSE, EIO_DUP2, + EIO_READ, EIO_WRITE, + EIO_READAHEAD, EIO_SENDFILE, + EIO_STAT, EIO_LSTAT, EIO_FSTAT, + EIO_TRUNCATE, EIO_FTRUNCATE, + EIO_UTIME, EIO_FUTIME, + EIO_CHMOD, EIO_FCHMOD, + EIO_CHOWN, EIO_FCHOWN, + EIO_SYNC, EIO_FSYNC, EIO_FDATASYNC, + EIO_UNLINK, EIO_RMDIR, EIO_MKDIR, EIO_RENAME, + EIO_MKNOD, EIO_READDIR, + EIO_LINK, EIO_SYMLINK, EIO_READLINK, + EIO_GROUP, EIO_NOP, + EIO_BUSY, +}; + +typedef double eio_tstamp; /* feel free to use double in your code directly */ + +/* eio request structure */ +/* this structure is mostly read-only */ +struct eio_req +{ + eio_req volatile *next; /* private */ + + ssize_t result; /* result of syscall, e.g. result = read (... */ + off_t offs; /* read, write, truncate, readahead: file offset; mknod: dev_t */ + size_t size; /* read, write, readahead, sendfile: length */ + void *ptr1; /* all applicable requests: pathname, old name */ + void *ptr2; /* all applicable requests: new name or memory buffer */ + eio_tstamp nv1; /* utime, futime: atime; busy: sleep time */ + eio_tstamp nv2; /* utime, futime: mtime */ + + int type; /* EIO_xxx constant */ + int int1; /* all applicable requests: file descriptor; sendfile: output fd; open: flags */ + long int2; /* chown, fchown: uid; sendfile: input fd; open, chmod, mkdir, mknod: file mode */ + long int3; /* chown, fchown: gid */ + int errorno; /* errno value on syscall return */ + + unsigned char flags; /* private */ + unsigned char pri; /* the priority */ + + void (*feed)(eio_req *req); + + EIO_COMMON; + + eio_req *grp, *grp_prev, *grp_next, *grp_first; /* private */ +}; + +enum { + EIO_FLAG_CANCELLED = 0x01, /* request was cancelled */ + EIO_FLAG_PTR2_FREE = 0x02, /* need to free(ptr2) */ +}; + +enum { + EIO_PRI_MIN = -4, + EIO_PRI_MAX = 4, + + EIO_DEFAULT_PRI = 0, + EIO_PRI_BIAS = -EIO_PRI_MIN, + EIO_NUM_PRI = EIO_PRI_MAX + EIO_PRI_BIAS + 1, +}; + +/* returns < 0 on error, errno set + * need_poll, if non-zero, will be called when results are available + * and eio_poll_cb needs to be invoked (it MUST NOT call eio_poll_cb itself). + * done_poll is called when the need to poll is gone. + */ +int eio_init (void (*want_poll)(void), void (*done_poll)(void)); + +/* must be called regularly to handle pending requests */ +/* returns 0 if all requests were handled, -1 if not, or the value of EIO_FINISH if != 0 */ +int eio_poll (void); + +/* stop polling if poll took longer than duration seconds */ +void eio_set_max_poll_time (eio_tstamp nseconds); +/* do not handle more then count requests in one call to eio_poll_cb */ +void eio_set_max_poll_reqs (unsigned int nreqs); +/* when != 0, then eio_submit blocks as long as nready > count */ +void eio_set_max_outstanding (unsigned int maxreqs); +/* set maxinum number of idle threads */ +void eio_set_max_idle (unsigned int nthreads); + +/* set minimum required number + * maximum wanted number + * or maximum idle number of threads */ +void eio_set_min_parallel (unsigned int nthreads); +void eio_set_max_parallel (unsigned int nthreads); +void eio_set_max_idle (unsigned int nthreads); + +unsigned int eio_nreqs (void); /* number of requests in-flight */ +unsigned int eio_nready (void); /* number of not-yet handled requests */ +unsigned int eio_npending (void); /* numbe rof finished but unhandled requests */ +unsigned int eio_nthreads (void); /* number of worker threads in use currently */ + +/*****************************************************************************/ +/* high-level request API */ + +eio_req *eio_fsync (int fd, eio_cb cb); +eio_req *eio_fdatasync (int fd, eio_cb cb); +eio_req *eio_dupclose (int fd, eio_cb cb); +eio_req *eio_readahead (int fd, off_t offset, size_t length, eio_cb cb); +eio_req *eio_read (int fd, off_t offs, size_t length, char *data, eio_cb cb); +eio_req *eio_write (int fd, off_t offs, size_t length, char *data, eio_cb cb); +eio_req *eio_fstat (int fd, eio_cb cb); /* stat buffer=ptr2 allocates dynamically */ +eio_req *eio_futime (int fd, eio_tstamp atime, eio_tstamp mtime, eio_cb cb); +eio_req *eio_ftruncate (int fd, off_t offset, eio_cb cb); +eio_req *eio_fchmod (int fd, mode_t mode, eio_cb cb); +eio_req *eio_fchown (int fd, uid_t uid, gid_t gid, eio_cb cb); +eio_req *eio_dup2 (int fd, int fd2, eio_cb cb); +eio_req *eio_sendfile (int out_fd, int in_fd, off_t in_offset, size_t length, eio_cb cb); +eio_req *eio_open (const char *path, int flags, mode_t mode, eio_cb cb); +eio_req *eio_readlink (const char *path, eio_cb cb); /* result=ptr2 allocated dynamically */ +eio_req *eio_stat (const char *path, eio_cb cb); /* stat buffer=ptr2 allocates dynamically */ +eio_req *eio_lstat (const char *path, eio_cb cb); /* stat buffer=ptr2 allocates dynamically */ +eio_req *eio_utime (const char *path, eio_tstamp atime, eio_tstamp mtime, eio_cb cb); +eio_req *eio_truncate (const char *path, off_t offset, eio_cb cb); +eio_req *eio_chmod (const char *path, mode_t mode, eio_cb cb); +eio_req *eio_mkdir (const char *path, mode_t mode, eio_cb cb); +eio_req *eio_chown (const char *path, uid_t uid, gid_t gid, eio_cb cb); +eio_req *eio_unlink (const char *path, eio_cb cb); +eio_req *eio_rmdir (const char *path, eio_cb cb); +eio_req *eio_readdir (const char *path, eio_cb cb); /* result=ptr2 allocated dynamically */ +eio_req *eio_mknod (const char *path, mode_t mode, dev_t dev, eio_cb cb); +eio_req *eio_busy (eio_tstamp delay, eio_cb cb); /* ties a thread for this long, simulating busyness */ +eio_req *eio_nop (eio_cb cb); /* does nothing except go through the whole process */ + +/* for groups */ +eio_req *eio_grp (eio_cb cb); +void eio_grp_feed (eio_req *grp, int limit, void (*feed)(eio_req *req)); +void eio_grp_add (eio_req *grp, eio_req *req); +void eio_grp_cancel (eio_req *grp); /* cancels all sub requests but not the group */ + +/*****************************************************************************/ +/* low-level request API */ + +/* must be used to initialise eio_req's */ +#define EIO_INIT(req,prio,finish_cb, destroy_cb) \ + memset ((req), 0, sizeof (eio_req)); \ + (req)->pri = (prio) + EIO_PRI_BIAS; \ + (req)->finish = (finish_cb); \ + (req)->destroy = (destroy_cb) + +/* true if the request was cancelled, useful in the invoke callback */ +#define EIO_CANCELLED(req) ((req)->flags & EIO_FLAG_CANCELLED) + +/* submit a request for execution */ +void eio_submit (eio_req *req); +/* cancel a request as soon fast as possible */ +void eio_cancel (eio_req *req); +/* destroy a request that has never been submitted */ +void eio_destroy (eio_req *req); + +#endif + |