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      1 /*
      2  * ioe_e4defrag:  ioengine for git://git.kernel.dk/fio.git
      3  *
      4  * IO engine that does regular EXT4_IOC_MOVE_EXT ioctls to simulate
      5  * defragment activity
      6  *
      7  */
      8 
      9 #include <sys/types.h>
     10 #include <sys/stat.h>
     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 
     21 #ifndef EXT4_IOC_MOVE_EXT
     22 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
     23 struct move_extent {
     24 	__u32 reserved;         /* should be zero */
     25 	__u32 donor_fd;         /* donor file descriptor */
     26 	__u64 orig_start;       /* logical start offset in block for orig */
     27 	__u64 donor_start;      /* logical start offset in block for donor */
     28 	__u64 len;              /* block length to be moved */
     29 	__u64 moved_len;        /* moved block length */
     30 };
     31 #endif
     32 
     33 struct e4defrag_data {
     34 	int donor_fd;
     35 	int bsz;
     36 };
     37 
     38 struct e4defrag_options {
     39 	struct thread_data *td;
     40 	unsigned int inplace;
     41 	char * donor_name;
     42 };
     43 
     44 static struct fio_option options[] = {
     45 	{
     46 		.name	= "donorname",
     47 		.type	= FIO_OPT_STR_STORE,
     48 		.off1	= offsetof(struct e4defrag_options, donor_name),
     49 		.help	= "File used as a block donor",
     50 		.category = FIO_OPT_C_ENGINE,
     51 		.group	= FIO_OPT_G_E4DEFRAG,
     52 	},
     53 	{
     54 		.name	= "inplace",
     55 		.type	= FIO_OPT_INT,
     56 		.off1	= offsetof(struct e4defrag_options, inplace),
     57 		.minval	= 0,
     58 		.maxval	= 1,
     59 		.help	= "Alloc and free space inside defrag event",
     60 		.category = FIO_OPT_C_ENGINE,
     61 		.group	= FIO_OPT_G_E4DEFRAG,
     62 	},
     63 	{
     64 		.name	= NULL,
     65 	},
     66 };
     67 
     68 static int fio_e4defrag_init(struct thread_data *td)
     69 {
     70 	int r, len = 0;
     71 	struct e4defrag_options *o = td->eo;
     72 	struct e4defrag_data *ed;
     73 	struct stat stub;
     74 	char donor_name[PATH_MAX];
     75 
     76 	if (!strlen(o->donor_name)) {
     77 		log_err("'donorname' options required\n");
     78 		return 1;
     79 	}
     80 
     81 	ed = malloc(sizeof(*ed));
     82 	if (!ed) {
     83 		td_verror(td, ENOMEM, "io_queue_init");
     84 		return 1;
     85 	}
     86 	memset(ed, 0 ,sizeof(*ed));
     87 
     88 	if (td->o.directory)
     89 		len = sprintf(donor_name, "%s/", td->o.directory);
     90 	sprintf(donor_name + len, "%s", o->donor_name);
     91 
     92 	ed->donor_fd = open(donor_name, O_CREAT|O_WRONLY, 0644);
     93 	if (ed->donor_fd < 0) {
     94 		td_verror(td, errno, "io_queue_init");
     95 		log_err("Can't open donor file %s err:%d", donor_name, ed->donor_fd);
     96 		free(ed);
     97 		return 1;
     98 	}
     99 
    100 	if (!o->inplace) {
    101 		long long len = td->o.file_size_high - td->o.start_offset;
    102 		r = fallocate(ed->donor_fd, 0, td->o.start_offset, len);
    103 		if (r)
    104 			goto err;
    105 	}
    106 	r = fstat(ed->donor_fd, &stub);
    107 	if (r)
    108 		goto err;
    109 
    110 	ed->bsz = stub.st_blksize;
    111 	td->io_ops->data = ed;
    112 	return 0;
    113 err:
    114 	td_verror(td, errno, "io_queue_init");
    115 	close(ed->donor_fd);
    116 	free(ed);
    117 	return 1;
    118 }
    119 
    120 static void fio_e4defrag_cleanup(struct thread_data *td)
    121 {
    122 	struct e4defrag_data *ed = td->io_ops->data;
    123 	if (ed) {
    124 		if (ed->donor_fd >= 0)
    125 			close(ed->donor_fd);
    126 		free(ed);
    127 	}
    128 }
    129 
    130 
    131 static int fio_e4defrag_queue(struct thread_data *td, struct io_u *io_u)
    132 {
    133 
    134 	int ret;
    135 	unsigned long long len;
    136 	struct move_extent me;
    137 	struct fio_file *f = io_u->file;
    138 	struct e4defrag_data *ed = td->io_ops->data;
    139 	struct e4defrag_options *o = td->eo;
    140 
    141 	fio_ro_check(td, io_u);
    142 
    143 	/* Theoretically defragmentation should not change data, but it
    144 	 * changes data layout. So this function handle only DDIR_WRITE
    145 	 * in order to satisfy strict read only access pattern
    146 	 */
    147 	if (io_u->ddir != DDIR_WRITE) {
    148 		io_u->error = EINVAL;
    149 		return FIO_Q_COMPLETED;
    150 	}
    151 
    152 	if (o->inplace) {
    153 		ret = fallocate(ed->donor_fd, 0, io_u->offset, io_u->xfer_buflen);
    154 		if (ret)
    155 			goto out;
    156 	}
    157 
    158 	memset(&me, 0, sizeof(me));
    159 	me.donor_fd = ed->donor_fd;
    160 	me.orig_start = io_u->offset / ed->bsz;
    161 	me.donor_start = me.orig_start;
    162 	len = (io_u->offset + io_u->xfer_buflen + ed->bsz -1);
    163 	me.len = len / ed->bsz - me.orig_start;
    164 
    165 	ret = ioctl(f->fd, EXT4_IOC_MOVE_EXT, &me);
    166 	len = me.moved_len * ed->bsz;
    167 
    168 	if (len > io_u->xfer_buflen)
    169 		len = io_u->xfer_buflen;
    170 
    171 	if (len != io_u->xfer_buflen) {
    172 		io_u->resid = io_u->xfer_buflen - len;
    173 		io_u->error = 0;
    174 	}
    175 	if (ret)
    176 		io_u->error = errno;
    177 
    178 	if (o->inplace)
    179 		ret = ftruncate(ed->donor_fd, 0);
    180 out:
    181 	if (ret && !io_u->error)
    182 		io_u->error = errno;
    183 
    184 	return FIO_Q_COMPLETED;
    185 }
    186 
    187 static struct ioengine_ops ioengine = {
    188 	.name			= "e4defrag",
    189 	.version		= FIO_IOOPS_VERSION,
    190 	.init			= fio_e4defrag_init,
    191 	.queue			= fio_e4defrag_queue,
    192 	.open_file		= generic_open_file,
    193 	.close_file		= generic_close_file,
    194 	.get_file_size		= generic_get_file_size,
    195 	.flags			= FIO_SYNCIO,
    196 	.cleanup		= fio_e4defrag_cleanup,
    197 	.options		= options,
    198 	.option_struct_size	= sizeof(struct e4defrag_options),
    199 
    200 };
    201 
    202 static void fio_init fio_syncio_register(void)
    203 {
    204 	register_ioengine(&ioengine);
    205 }
    206 
    207 static void fio_exit fio_syncio_unregister(void)
    208 {
    209 	unregister_ioengine(&ioengine);
    210 }
    211