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device-mapper.c revision 1.6.2.2
      1 /*        $NetBSD: device-mapper.c,v 1.6.2.2 2009/05/04 08:12:36 yamt Exp $ */
      2 
      3 /*
      4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Adam Hamsik.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * I want to say thank you to all people who helped me with this project.
     34  */
     35 
     36 #include <sys/types.h>
     37 #include <sys/param.h>
     38 
     39 #include <sys/buf.h>
     40 #include <sys/conf.h>
     41 #include <sys/dkio.h>
     42 #include <sys/disk.h>
     43 #include <sys/disklabel.h>
     44 #include <sys/ioctl.h>
     45 #include <sys/ioccom.h>
     46 #include <sys/kmem.h>
     47 #include <sys/module.h>
     48 
     49 #include "netbsd-dm.h"
     50 #include "dm.h"
     51 
     52 static dev_type_open(dmopen);
     53 static dev_type_close(dmclose);
     54 static dev_type_read(dmread);
     55 static dev_type_write(dmwrite);
     56 static dev_type_ioctl(dmioctl);
     57 static dev_type_strategy(dmstrategy);
     58 static dev_type_size(dmsize);
     59 
     60 /* attach and detach routines */
     61 int dmattach(void);
     62 int dmdestroy(void);
     63 
     64 static int dm_cmd_to_fun(prop_dictionary_t);
     65 static int disk_ioctl_switch(dev_t, u_long, void *);
     66 static int dm_ioctl_switch(u_long);
     67 static void dmminphys(struct buf *);
     68 
     69 /* ***Variable-definitions*** */
     70 const struct bdevsw dm_bdevsw = {
     71 	.d_open = dmopen,
     72 	.d_close = dmclose,
     73 	.d_strategy = dmstrategy,
     74 	.d_ioctl = dmioctl,
     75 	.d_dump = nodump,
     76 	.d_psize = dmsize,
     77 	.d_flag = D_DISK | D_MPSAFE
     78 };
     79 
     80 const struct cdevsw dm_cdevsw = {
     81 	.d_open = dmopen,
     82 	.d_close = dmclose,
     83 	.d_read = dmread,
     84 	.d_write = dmwrite,
     85 	.d_ioctl = dmioctl,
     86 	.d_stop = nostop,
     87 	.d_tty = notty,
     88 	.d_poll = nopoll,
     89 	.d_mmap = nommap,
     90 	.d_kqfilter = nokqfilter,
     91 	.d_flag = D_DISK | D_MPSAFE
     92 };
     93 
     94 const struct dkdriver dmdkdriver = {
     95 	.d_strategy = dmstrategy
     96 };
     97 
     98 extern uint64_t dev_counter;
     99 
    100 /*
    101  * This array is used to translate cmd to function pointer.
    102  *
    103  * Interface between libdevmapper and lvm2tools uses different
    104  * names for one IOCTL call because libdevmapper do another thing
    105  * then. When I run "info" or "mknodes" libdevmapper will send same
    106  * ioctl to kernel but will do another things in userspace.
    107  *
    108  */
    109 struct cmd_function cmd_fn[] = {
    110 		{ .cmd = "version", .fn = dm_get_version_ioctl},
    111 		{ .cmd = "targets", .fn = dm_list_versions_ioctl},
    112 		{ .cmd = "create",  .fn = dm_dev_create_ioctl},
    113 		{ .cmd = "info",    .fn = dm_dev_status_ioctl},
    114 		{ .cmd = "mknodes", .fn = dm_dev_status_ioctl},
    115 		{ .cmd = "names",   .fn = dm_dev_list_ioctl},
    116 		{ .cmd = "suspend", .fn = dm_dev_suspend_ioctl},
    117 		{ .cmd = "remove",  .fn = dm_dev_remove_ioctl},
    118 		{ .cmd = "rename",  .fn = dm_dev_rename_ioctl},
    119 		{ .cmd = "resume",  .fn = dm_dev_resume_ioctl},
    120 		{ .cmd = "clear",   .fn = dm_table_clear_ioctl},
    121 		{ .cmd = "deps",    .fn = dm_table_deps_ioctl},
    122 		{ .cmd = "reload",  .fn = dm_table_load_ioctl},
    123 		{ .cmd = "status",  .fn = dm_table_status_ioctl},
    124 		{ .cmd = "table",   .fn = dm_table_status_ioctl},
    125 		{NULL, NULL}
    126 };
    127 
    128 
    129 MODULE(MODULE_CLASS_DRIVER, dm, NULL);
    130 
    131 /* New module handle routine */
    132 static int
    133 dm_modcmd(modcmd_t cmd, void *arg)
    134 {
    135 #ifdef _MODULE
    136 	int bmajor = -1, cmajor = -1;
    137 
    138 	switch (cmd) {
    139 	case MODULE_CMD_INIT:
    140 		dmattach();
    141 		return devsw_attach("dm", &dm_bdevsw, &bmajor,
    142 		    &dm_cdevsw, &cmajor);
    143 		break;
    144 
    145 	case MODULE_CMD_FINI:
    146 		/*
    147 		 * Disable unloading of dm module if there are any devices
    148 		 * defined in driver. This is probably too strong we need
    149 		 * to disable auto-unload only if there is mounted dm device
    150 		 * present.
    151 		 */
    152 		if (dev_counter > 0)
    153 			return EBUSY;
    154 		dmdestroy();
    155 		return devsw_detach(&dm_bdevsw, &dm_cdevsw);
    156 		break;
    157 	case MODULE_CMD_STAT:
    158 		return ENOTTY;
    159 
    160 	default:
    161 		return ENOTTY;
    162 	}
    163 
    164 	return 0;
    165 #else
    166 
    167 	if (cmd == MODULE_CMD_INIT)
    168 		return 0;
    169 	return ENOTTY;
    170 
    171 #endif /* _MODULE */
    172 }
    173 
    174 
    175 /* attach routine */
    176 int
    177 dmattach(void)
    178 {
    179 	dm_target_init();
    180 	dm_dev_init();
    181 	dm_pdev_init();
    182 
    183 	return 0;
    184 }
    185 
    186 /* Destroy routine */
    187 int
    188 dmdestroy(void)
    189 {
    190 	dm_dev_destroy();
    191 	dm_pdev_destroy();
    192 	dm_target_destroy();
    193 
    194 	return 0;
    195 }
    196 
    197 static int
    198 dmopen(dev_t dev, int flags, int mode, struct lwp *l)
    199 {
    200 	aprint_debug("open routine called %" PRIu32 "\n", minor(dev));
    201 	return 0;
    202 }
    203 
    204 static int
    205 dmclose(dev_t dev, int flags, int mode, struct lwp *l)
    206 {
    207 	aprint_debug("CLOSE routine called\n");
    208 
    209 	return 0;
    210 }
    211 
    212 
    213 static int
    214 dmioctl(dev_t dev, const u_long cmd, void *data, int flag, struct lwp *l)
    215 {
    216 	int r;
    217 	prop_dictionary_t dm_dict_in;
    218 
    219 	r = 0;
    220 
    221 	aprint_debug("dmioctl called\n");
    222 
    223 	KASSERT(data != NULL);
    224 
    225 	if (disk_ioctl_switch(dev, cmd, data) != 0) {
    226 		struct plistref *pref = (struct plistref *) data;
    227 
    228 		if((r = prop_dictionary_copyin_ioctl(pref, cmd, &dm_dict_in)) != 0)
    229 			return r;
    230 
    231 		dm_check_version(dm_dict_in);
    232 
    233 		/* call cmd selected function */
    234 		if ((r = dm_ioctl_switch(cmd)) != 0) {
    235 			prop_object_release(dm_dict_in);
    236 			return r;
    237 		}
    238 
    239 		/* run ioctl routine */
    240 		if ((r = dm_cmd_to_fun(dm_dict_in)) != 0) {
    241 			prop_object_release(dm_dict_in);
    242 			return r;
    243 		}
    244 
    245 		r = prop_dictionary_copyout_ioctl(pref, cmd, dm_dict_in);
    246 
    247 		prop_object_release(dm_dict_in);
    248 	}
    249 
    250 	return r;
    251 }
    252 
    253 /*
    254  * Translate command sent from libdevmapper to func.
    255  */
    256 static int
    257 dm_cmd_to_fun(prop_dictionary_t dm_dict){
    258 	int i, r;
    259 	prop_string_t command;
    260 
    261 	r = 0;
    262 
    263 	if ((command = prop_dictionary_get(dm_dict, DM_IOCTL_COMMAND)) == NULL)
    264 		return EINVAL;
    265 
    266 	for(i = 0; cmd_fn[i].cmd != NULL; i++)
    267 		if (prop_string_equals_cstring(command, cmd_fn[i].cmd))
    268 			break;
    269 
    270 	if (cmd_fn[i].cmd == NULL)
    271 		return EINVAL;
    272 
    273 	aprint_debug("ioctl %s called\n", cmd_fn[i].cmd);
    274 	r = cmd_fn[i].fn(dm_dict);
    275 
    276 	return r;
    277 }
    278 
    279 /* Call apropriate ioctl handler function. */
    280 static int
    281 dm_ioctl_switch(u_long cmd)
    282 {
    283 	int r;
    284 
    285 	r = 0;
    286 
    287 	switch(cmd) {
    288 
    289 	case NETBSD_DM_IOCTL:
    290 		aprint_debug("NetBSD_DM_IOCTL called\n");
    291 		break;
    292 
    293 	default:
    294 		 aprint_debug("unknown ioctl called\n");
    295 		 return ENOTTY;
    296 		 break; /* NOT REACHED */
    297 	}
    298 
    299 	 return r;
    300 }
    301 
    302  /*
    303   * Check for disk specific ioctls.
    304   */
    305 
    306 static int
    307 disk_ioctl_switch(dev_t dev, u_long cmd, void *data)
    308 {
    309 	dm_dev_t *dmv;
    310 
    311 	switch(cmd) {
    312 	case DIOCGWEDGEINFO:
    313 	{
    314 		struct dkwedge_info *dkw = (void *) data;
    315 
    316 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
    317 			return ENOENT;
    318 
    319 		aprint_normal("DIOCGWEDGEINFO ioctl called\n");
    320 
    321 		strlcpy(dkw->dkw_devname, dmv->name, 16);
    322 		strlcpy(dkw->dkw_wname, dmv->name, DM_NAME_LEN);
    323 		strlcpy(dkw->dkw_parent, dmv->name, 16);
    324 
    325 		dkw->dkw_offset = 0;
    326 		dkw->dkw_size = dm_table_size(&dmv->table_head);
    327 		strcpy(dkw->dkw_ptype, DKW_PTYPE_FFS);
    328 
    329 		dm_dev_unbusy(dmv);
    330 		break;
    331 	}
    332 
    333 	case DIOCGDINFO:
    334 	{
    335 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
    336 			return ENOENT;
    337 
    338 		aprint_debug("DIOCGDINFO %d\n", dmv->diskp->dk_label->d_secsize);
    339 
    340 		*(struct disklabel *)data = *(dmv->diskp->dk_label);
    341 
    342 		dm_dev_unbusy(dmv);
    343 		break;
    344 	}
    345 
    346 	case DIOCGPART:
    347 	{
    348 		if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
    349 			return ENOENT;
    350 
    351 		((struct partinfo *)data)->disklab = dmv->diskp->dk_label;
    352 		((struct partinfo *)data)->part = &dmv->diskp->dk_label->d_partitions[0];
    353 
    354 		dm_dev_unbusy(dmv);
    355 		break;
    356 	}
    357 	case DIOCWDINFO:
    358 	case DIOCSDINFO:
    359 	case DIOCKLABEL:
    360 	case DIOCWLABEL:
    361 	case DIOCGDEFLABEL:
    362 
    363 	default:
    364 		aprint_debug("unknown disk_ioctl called\n");
    365 		return 1;
    366 		break; /* NOT REACHED */
    367 	}
    368 
    369 	return 0;
    370 }
    371 
    372 /*
    373  * Do all IO operations on dm logical devices.
    374  */
    375 static void
    376 dmstrategy(struct buf *bp)
    377 {
    378 	dm_dev_t *dmv;
    379 	dm_table_t  *tbl;
    380 	dm_table_entry_t *table_en;
    381 	struct buf *nestbuf;
    382 
    383 	uint32_t dev_type;
    384 
    385 	uint64_t buf_start, buf_len, issued_len;
    386 	uint64_t table_start, table_end;
    387 	uint64_t start, end;
    388 
    389 	buf_start = bp->b_blkno * DEV_BSIZE;
    390 	buf_len = bp->b_bcount;
    391 
    392 	tbl = NULL;
    393 
    394 	table_end = 0;
    395 	dev_type = 0;
    396 	issued_len = 0;
    397 
    398 	if ((dmv = dm_dev_lookup(NULL, NULL, minor(bp->b_dev))) == NULL) {
    399 		bp->b_error = EIO;
    400 		bp->b_resid = bp->b_bcount;
    401 		biodone(bp);
    402 		return;
    403 	}
    404 
    405 	/* FIXME: have to be called with IPL_BIO*/
    406 	disk_busy(dmv->diskp);
    407 
    408 	/* Select active table */
    409 	tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);
    410 
    411 	 /* Nested buffers count down to zero therefore I have
    412 	    to set bp->b_resid to maximal value. */
    413 	bp->b_resid = bp->b_bcount;
    414 
    415 	/*
    416 	 * Find out what tables I want to select.
    417 	 */
    418 	SLIST_FOREACH(table_en, tbl, next)
    419 	{
    420 		/* I need need number of bytes not blocks. */
    421 		table_start = table_en->start * DEV_BSIZE;
    422 		/*
    423 		 * I have to sub 1 from table_en->length to prevent
    424 		 * off by one error
    425 		 */
    426 		table_end = table_start + (table_en->length)* DEV_BSIZE;
    427 
    428 		start = MAX(table_start, buf_start);
    429 
    430 		end = MIN(table_end, buf_start + buf_len);
    431 
    432 		aprint_debug("----------------------------------------\n");
    433 		aprint_debug("table_start %010" PRIu64", table_end %010"
    434 		    PRIu64 "\n", table_start, table_end);
    435 		aprint_debug("buf_start %010" PRIu64", buf_len %010"
    436 		    PRIu64"\n", buf_start, buf_len);
    437 		aprint_debug("start-buf_start %010"PRIu64", end %010"
    438 		    PRIu64"\n", start - buf_start, end);
    439 		aprint_debug("start %010" PRIu64" , end %010"
    440                     PRIu64"\n", start, end);
    441 		aprint_debug("\n----------------------------------------\n");
    442 
    443 		if (start < end) {
    444 			/* create nested buffer  */
    445 			nestbuf = getiobuf(NULL, true);
    446 
    447 			nestiobuf_setup(bp, nestbuf, start - buf_start,
    448 			    (end - start));
    449 
    450 			issued_len += end - start;
    451 
    452 			/* I need number of blocks. */
    453 			nestbuf->b_blkno = (start - table_start) / DEV_BSIZE;
    454 
    455 			table_en->target->strategy(table_en, nestbuf);
    456 		}
    457 	}
    458 
    459 	if (issued_len < buf_len)
    460 		nestiobuf_done(bp, buf_len - issued_len, EINVAL);
    461 
    462 	/* FIXME have to be called with SPL_BIO*/
    463 	disk_unbusy(dmv->diskp, buf_len, bp != NULL ? bp->b_flags & B_READ : 0);
    464 
    465 	dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
    466 	dm_dev_unbusy(dmv);
    467 
    468 	return;
    469 }
    470 
    471 
    472 static int
    473 dmread(dev_t dev, struct uio *uio, int flag)
    474 {
    475 	return (physio(dmstrategy, NULL, dev, B_READ, dmminphys, uio));
    476 }
    477 
    478 static int
    479 dmwrite(dev_t dev, struct uio *uio, int flag)
    480 {
    481 	return (physio(dmstrategy, NULL, dev, B_WRITE, dmminphys, uio));
    482 }
    483 
    484 static int
    485 dmsize(dev_t dev)
    486 {
    487 	dm_dev_t *dmv;
    488 	uint64_t size;
    489 
    490 	size = 0;
    491 
    492 	if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
    493 			return -ENOENT;
    494 
    495 	size = dm_table_size(&dmv->table_head);
    496 	dm_dev_unbusy(dmv);
    497 
    498   	return size;
    499 }
    500 
    501 static void
    502 dmminphys(struct buf *bp)
    503 {
    504 	bp->b_bcount = MIN(bp->b_bcount, MAXPHYS);
    505 }
    506 
    507  /*
    508   * Load the label information on the named device
    509   * Actually fabricate a disklabel.
    510   *
    511   * EVENTUALLY take information about different
    512   * data tracks from the TOC and put it in the disklabel
    513   *
    514   * Copied from vnd code.
    515   */
    516 void
    517 dmgetdisklabel(struct disklabel *lp, dm_table_head_t *head)
    518 {
    519 	struct partition *pp;
    520 	int dmp_size;
    521 
    522 	dmp_size = dm_table_size(head);
    523 
    524 	/*
    525 	 * Size must be at least 2048 DEV_BSIZE blocks
    526 	 * (1M) in order to use this geometry.
    527 	 */
    528 
    529 	lp->d_secperunit = dmp_size;
    530 	lp->d_secsize = DEV_BSIZE;
    531 	lp->d_nsectors = 32;
    532 	lp->d_ntracks = 64;
    533 	lp->d_ncylinders = dmp_size / (lp->d_nsectors * lp->d_ntracks);
    534 	lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors;
    535 
    536 	strncpy(lp->d_typename, "lvm", sizeof(lp->d_typename));
    537 	lp->d_type = DTYPE_DM;
    538 	strncpy(lp->d_packname, "fictitious", sizeof(lp->d_packname));
    539 	lp->d_rpm = 3600;
    540 	lp->d_interleave = 1;
    541 	lp->d_flags = 0;
    542 
    543 	pp = &lp->d_partitions[0];
    544 	/*
    545 	 * This is logical offset and therefore it can be 0
    546 	 * I will consider table offsets later in dmstrategy.
    547 	 */
    548 	pp->p_offset = 0;
    549 	pp->p_size = dmp_size * DEV_BSIZE;
    550 	pp->p_fstype = FS_BSDFFS;  /* default value */
    551 	lp->d_npartitions = 1;
    552 
    553 	lp->d_magic = DISKMAGIC;
    554 	lp->d_magic2 = DISKMAGIC;
    555 	lp->d_checksum = dkcksum(lp);
    556 
    557 	return;
    558 }
    559