Home | History | Annotate | Download | only in engines 
      1 /*
      2  * falloc: ioengine for git://git.kernel.dk/fio.git
      3  *
      4  * IO engine that does regular fallocate to simulate data transfer
      5  * as fio ioengine.
      6  * DDIR_READ  does fallocate(,mode = FALLOC_FL_KEEP_SIZE,)
      7  * DDIR_WRITE does fallocate(,mode = 0) : fallocate with size extension
      8  * DDIR_TRIM  does fallocate(,mode = FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)
      9  *
     10  */
     11 #include <stdio.h>
     12 #include <stdlib.h>
     13 #include <unistd.h>
     14 #include <sys/uio.h>
     15 #include <errno.h>
     16 #include <assert.h>
     17 #include <fcntl.h>
     18 
     19 #include "../fio.h"
     20 #include "../filehash.h"
     21 
     22 /*
     23  * generic_open_file is not appropriate because does not allow to perform
     24  * TRIM in to file
     25  */
     26 static int open_file(struct thread_data *td, struct fio_file *f)
     27 {
     28 	int from_hash = 0;
     29 
     30 	dprint(FD_FILE, "fd open %s\n", f->file_name);
     31 
     32 	if (f->filetype != FIO_TYPE_FILE) {
     33 		log_err("fio: only files are supported fallocate \n");
     34 		return 1;
     35 	}
     36 	if (!strcmp(f->file_name, "-")) {
     37 		log_err("fio: can't read/write to stdin/out\n");
     38 		return 1;
     39 	}
     40 
     41 open_again:
     42 	from_hash = file_lookup_open(f, O_CREAT|O_RDWR);
     43 
     44 	if (f->fd == -1) {
     45 		char buf[FIO_VERROR_SIZE];
     46 		int e = errno;
     47 
     48 		snprintf(buf, sizeof(buf), "open(%s)", f->file_name);
     49 		td_verror(td, e, buf);
     50 	}
     51 
     52 	if (!from_hash && f->fd != -1) {
     53 		if (add_file_hash(f)) {
     54 			int fio_unused ret;
     55 
     56 			/*
     57 			 * OK to ignore, we haven't done anything with it
     58 			 */
     59 			ret = generic_close_file(td, f);
     60 			goto open_again;
     61 		}
     62 	}
     63 
     64 	return 0;
     65 }
     66 
     67 #ifndef FALLOC_FL_KEEP_SIZE
     68 #define FALLOC_FL_KEEP_SIZE     0x01 /* default is extend size */
     69 #endif
     70 #ifndef FALLOC_FL_PUNCH_HOLE
     71 #define FALLOC_FL_PUNCH_HOLE    0x02 /* de-allocates range */
     72 #endif
     73 static int fio_fallocate_queue(struct thread_data *td, struct io_u *io_u)
     74 {
     75 	struct fio_file *f = io_u->file;
     76 	int ret;
     77 	int flags = 0;
     78 
     79 	fio_ro_check(td, io_u);
     80 
     81 	if (io_u->ddir == DDIR_READ)
     82 		flags = FALLOC_FL_KEEP_SIZE;
     83 	else if (io_u->ddir == DDIR_WRITE)
     84 		flags = 0;
     85 	else if (io_u->ddir == DDIR_TRIM)
     86 		flags = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
     87 
     88 	ret = fallocate(f->fd, flags, io_u->offset, io_u->xfer_buflen);
     89 
     90 	if (ret)
     91 		io_u->error = errno;
     92 
     93 	return FIO_Q_COMPLETED;
     94 }
     95 
     96 static struct ioengine_ops ioengine = {
     97 	.name		= "falloc",
     98 	.version	= FIO_IOOPS_VERSION,
     99 	.queue		= fio_fallocate_queue,
    100 	.open_file	= open_file,
    101 	.close_file	= generic_close_file,
    102 	.get_file_size	= generic_get_file_size,
    103 	.flags		= FIO_SYNCIO
    104 };
    105 
    106 static void fio_init fio_syncio_register(void)
    107 {
    108 	register_ioengine(&ioengine);
    109 }
    110 
    111 static void fio_exit fio_syncio_unregister(void)
    112 {
    113 	unregister_ioengine(&ioengine);
    114 }
    115