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v4.17
   1/*
   2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18#include "xfs.h"
  19#include "xfs_fs.h"
  20#include "xfs_shared.h"
  21#include "xfs_format.h"
  22#include "xfs_log_format.h"
  23#include "xfs_trans_resv.h"
  24#include "xfs_bit.h"
  25#include "xfs_mount.h"
  26#include "xfs_defer.h"
  27#include "xfs_inode.h"
  28#include "xfs_bmap.h"
  29#include "xfs_bmap_util.h"
  30#include "xfs_bmap_btree.h"
  31#include "xfs_alloc.h"
  32#include "xfs_error.h"
  33#include "xfs_trans.h"
  34#include "xfs_trans_space.h"
  35#include "xfs_trace.h"
  36#include "xfs_buf.h"
  37#include "xfs_icache.h"
  38#include "xfs_rtalloc.h"
  39
  40
  41/*
  42 * Read and return the summary information for a given extent size,
  43 * bitmap block combination.
  44 * Keeps track of a current summary block, so we don't keep reading
  45 * it from the buffer cache.
  46 */
  47static int
  48xfs_rtget_summary(
  49	xfs_mount_t	*mp,		/* file system mount structure */
  50	xfs_trans_t	*tp,		/* transaction pointer */
  51	int		log,		/* log2 of extent size */
  52	xfs_rtblock_t	bbno,		/* bitmap block number */
  53	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
  54	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
  55	xfs_suminfo_t	*sum)		/* out: summary info for this block */
  56{
  57	return xfs_rtmodify_summary_int(mp, tp, log, bbno, 0, rbpp, rsb, sum);
  58}
  59
  60/*
  61 * Return whether there are any free extents in the size range given
  62 * by low and high, for the bitmap block bbno.
  63 */
  64STATIC int				/* error */
  65xfs_rtany_summary(
  66	xfs_mount_t	*mp,		/* file system mount structure */
  67	xfs_trans_t	*tp,		/* transaction pointer */
  68	int		low,		/* low log2 extent size */
  69	int		high,		/* high log2 extent size */
  70	xfs_rtblock_t	bbno,		/* bitmap block number */
  71	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
  72	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
  73	int		*stat)		/* out: any good extents here? */
  74{
  75	int		error;		/* error value */
  76	int		log;		/* loop counter, log2 of ext. size */
  77	xfs_suminfo_t	sum;		/* summary data */
  78
  79	/*
  80	 * Loop over logs of extent sizes.  Order is irrelevant.
  81	 */
  82	for (log = low; log <= high; log++) {
  83		/*
  84		 * Get one summary datum.
  85		 */
  86		error = xfs_rtget_summary(mp, tp, log, bbno, rbpp, rsb, &sum);
  87		if (error) {
  88			return error;
  89		}
  90		/*
  91		 * If there are any, return success.
  92		 */
  93		if (sum) {
  94			*stat = 1;
  95			return 0;
  96		}
  97	}
  98	/*
  99	 * Found nothing, return failure.
 100	 */
 101	*stat = 0;
 102	return 0;
 103}
 104
 105
 106/*
 107 * Copy and transform the summary file, given the old and new
 108 * parameters in the mount structures.
 109 */
 110STATIC int				/* error */
 111xfs_rtcopy_summary(
 112	xfs_mount_t	*omp,		/* old file system mount point */
 113	xfs_mount_t	*nmp,		/* new file system mount point */
 114	xfs_trans_t	*tp)		/* transaction pointer */
 115{
 116	xfs_rtblock_t	bbno;		/* bitmap block number */
 117	xfs_buf_t	*bp;		/* summary buffer */
 118	int		error;		/* error return value */
 119	int		log;		/* summary level number (log length) */
 120	xfs_suminfo_t	sum;		/* summary data */
 121	xfs_fsblock_t	sumbno;		/* summary block number */
 122
 123	bp = NULL;
 124	for (log = omp->m_rsumlevels - 1; log >= 0; log--) {
 125		for (bbno = omp->m_sb.sb_rbmblocks - 1;
 126		     (xfs_srtblock_t)bbno >= 0;
 127		     bbno--) {
 128			error = xfs_rtget_summary(omp, tp, log, bbno, &bp,
 129				&sumbno, &sum);
 130			if (error)
 131				return error;
 132			if (sum == 0)
 133				continue;
 134			error = xfs_rtmodify_summary(omp, tp, log, bbno, -sum,
 135				&bp, &sumbno);
 136			if (error)
 137				return error;
 138			error = xfs_rtmodify_summary(nmp, tp, log, bbno, sum,
 139				&bp, &sumbno);
 140			if (error)
 141				return error;
 142			ASSERT(sum > 0);
 143		}
 144	}
 145	return 0;
 146}
 147/*
 148 * Mark an extent specified by start and len allocated.
 149 * Updates all the summary information as well as the bitmap.
 150 */
 151STATIC int				/* error */
 152xfs_rtallocate_range(
 153	xfs_mount_t	*mp,		/* file system mount point */
 154	xfs_trans_t	*tp,		/* transaction pointer */
 155	xfs_rtblock_t	start,		/* start block to allocate */
 156	xfs_extlen_t	len,		/* length to allocate */
 157	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 158	xfs_fsblock_t	*rsb)		/* in/out: summary block number */
 159{
 160	xfs_rtblock_t	end;		/* end of the allocated extent */
 161	int		error;		/* error value */
 162	xfs_rtblock_t	postblock = 0;	/* first block allocated > end */
 163	xfs_rtblock_t	preblock = 0;	/* first block allocated < start */
 164
 165	end = start + len - 1;
 166	/*
 167	 * Assume we're allocating out of the middle of a free extent.
 168	 * We need to find the beginning and end of the extent so we can
 169	 * properly update the summary.
 170	 */
 171	error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
 172	if (error) {
 173		return error;
 174	}
 175	/*
 176	 * Find the next allocated block (end of free extent).
 177	 */
 178	error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
 179		&postblock);
 180	if (error) {
 181		return error;
 182	}
 183	/*
 184	 * Decrement the summary information corresponding to the entire
 185	 * (old) free extent.
 186	 */
 187	error = xfs_rtmodify_summary(mp, tp,
 188		XFS_RTBLOCKLOG(postblock + 1 - preblock),
 189		XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
 190	if (error) {
 191		return error;
 192	}
 193	/*
 194	 * If there are blocks not being allocated at the front of the
 195	 * old extent, add summary data for them to be free.
 196	 */
 197	if (preblock < start) {
 198		error = xfs_rtmodify_summary(mp, tp,
 199			XFS_RTBLOCKLOG(start - preblock),
 200			XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
 201		if (error) {
 202			return error;
 203		}
 204	}
 205	/*
 206	 * If there are blocks not being allocated at the end of the
 207	 * old extent, add summary data for them to be free.
 208	 */
 209	if (postblock > end) {
 210		error = xfs_rtmodify_summary(mp, tp,
 211			XFS_RTBLOCKLOG(postblock - end),
 212			XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
 213		if (error) {
 214			return error;
 215		}
 216	}
 217	/*
 218	 * Modify the bitmap to mark this extent allocated.
 219	 */
 220	error = xfs_rtmodify_range(mp, tp, start, len, 0);
 221	return error;
 222}
 223
 224/*
 225 * Attempt to allocate an extent minlen<=len<=maxlen starting from
 226 * bitmap block bbno.  If we don't get maxlen then use prod to trim
 227 * the length, if given.  Returns error; returns starting block in *rtblock.
 228 * The lengths are all in rtextents.
 229 */
 230STATIC int				/* error */
 231xfs_rtallocate_extent_block(
 232	xfs_mount_t	*mp,		/* file system mount point */
 233	xfs_trans_t	*tp,		/* transaction pointer */
 234	xfs_rtblock_t	bbno,		/* bitmap block number */
 235	xfs_extlen_t	minlen,		/* minimum length to allocate */
 236	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 237	xfs_extlen_t	*len,		/* out: actual length allocated */
 238	xfs_rtblock_t	*nextp,		/* out: next block to try */
 239	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 240	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 241	xfs_extlen_t	prod,		/* extent product factor */
 242	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 243{
 244	xfs_rtblock_t	besti;		/* best rtblock found so far */
 245	xfs_rtblock_t	bestlen;	/* best length found so far */
 246	xfs_rtblock_t	end;		/* last rtblock in chunk */
 247	int		error;		/* error value */
 248	xfs_rtblock_t	i;		/* current rtblock trying */
 249	xfs_rtblock_t	next;		/* next rtblock to try */
 250	int		stat;		/* status from internal calls */
 251
 252	/*
 253	 * Loop over all the extents starting in this bitmap block,
 254	 * looking for one that's long enough.
 255	 */
 256	for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
 257		end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
 258	     i <= end;
 259	     i++) {
 260		/*
 261		 * See if there's a free extent of maxlen starting at i.
 262		 * If it's not so then next will contain the first non-free.
 263		 */
 264		error = xfs_rtcheck_range(mp, tp, i, maxlen, 1, &next, &stat);
 265		if (error) {
 266			return error;
 267		}
 268		if (stat) {
 269			/*
 270			 * i for maxlen is all free, allocate and return that.
 271			 */
 272			error = xfs_rtallocate_range(mp, tp, i, maxlen, rbpp,
 273				rsb);
 274			if (error) {
 275				return error;
 276			}
 277			*len = maxlen;
 278			*rtblock = i;
 279			return 0;
 280		}
 281		/*
 282		 * In the case where we have a variable-sized allocation
 283		 * request, figure out how big this free piece is,
 284		 * and if it's big enough for the minimum, and the best
 285		 * so far, remember it.
 286		 */
 287		if (minlen < maxlen) {
 288			xfs_rtblock_t	thislen;	/* this extent size */
 289
 290			thislen = next - i;
 291			if (thislen >= minlen && thislen > bestlen) {
 292				besti = i;
 293				bestlen = thislen;
 294			}
 295		}
 296		/*
 297		 * If not done yet, find the start of the next free space.
 298		 */
 299		if (next < end) {
 300			error = xfs_rtfind_forw(mp, tp, next, end, &i);
 301			if (error) {
 302				return error;
 303			}
 304		} else
 305			break;
 306	}
 307	/*
 308	 * Searched the whole thing & didn't find a maxlen free extent.
 309	 */
 310	if (minlen < maxlen && besti != -1) {
 311		xfs_extlen_t	p;	/* amount to trim length by */
 312
 313		/*
 314		 * If size should be a multiple of prod, make that so.
 315		 */
 316		if (prod > 1 && (p = do_mod(bestlen, prod)))
 317			bestlen -= p;
 318		/*
 319		 * Allocate besti for bestlen & return that.
 320		 */
 321		error = xfs_rtallocate_range(mp, tp, besti, bestlen, rbpp, rsb);
 322		if (error) {
 323			return error;
 324		}
 325		*len = bestlen;
 326		*rtblock = besti;
 327		return 0;
 328	}
 329	/*
 330	 * Allocation failed.  Set *nextp to the next block to try.
 331	 */
 332	*nextp = next;
 333	*rtblock = NULLRTBLOCK;
 334	return 0;
 335}
 336
 337/*
 338 * Allocate an extent of length minlen<=len<=maxlen, starting at block
 339 * bno.  If we don't get maxlen then use prod to trim the length, if given.
 340 * Returns error; returns starting block in *rtblock.
 341 * The lengths are all in rtextents.
 342 */
 343STATIC int				/* error */
 344xfs_rtallocate_extent_exact(
 345	xfs_mount_t	*mp,		/* file system mount point */
 346	xfs_trans_t	*tp,		/* transaction pointer */
 347	xfs_rtblock_t	bno,		/* starting block number to allocate */
 348	xfs_extlen_t	minlen,		/* minimum length to allocate */
 349	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 350	xfs_extlen_t	*len,		/* out: actual length allocated */
 351	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 352	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 353	xfs_extlen_t	prod,		/* extent product factor */
 354	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 355{
 356	int		error;		/* error value */
 357	xfs_extlen_t	i;		/* extent length trimmed due to prod */
 358	int		isfree;		/* extent is free */
 359	xfs_rtblock_t	next;		/* next block to try (dummy) */
 360
 361	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 362	/*
 363	 * Check if the range in question (for maxlen) is free.
 364	 */
 365	error = xfs_rtcheck_range(mp, tp, bno, maxlen, 1, &next, &isfree);
 366	if (error) {
 367		return error;
 368	}
 369	if (isfree) {
 370		/*
 371		 * If it is, allocate it and return success.
 372		 */
 373		error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
 374		if (error) {
 375			return error;
 376		}
 377		*len = maxlen;
 378		*rtblock = bno;
 379		return 0;
 380	}
 381	/*
 382	 * If not, allocate what there is, if it's at least minlen.
 383	 */
 384	maxlen = next - bno;
 385	if (maxlen < minlen) {
 386		/*
 387		 * Failed, return failure status.
 388		 */
 389		*rtblock = NULLRTBLOCK;
 390		return 0;
 391	}
 392	/*
 393	 * Trim off tail of extent, if prod is specified.
 394	 */
 395	if (prod > 1 && (i = maxlen % prod)) {
 396		maxlen -= i;
 397		if (maxlen < minlen) {
 398			/*
 399			 * Now we can't do it, return failure status.
 400			 */
 401			*rtblock = NULLRTBLOCK;
 402			return 0;
 403		}
 404	}
 405	/*
 406	 * Allocate what we can and return it.
 407	 */
 408	error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
 409	if (error) {
 410		return error;
 411	}
 412	*len = maxlen;
 413	*rtblock = bno;
 414	return 0;
 415}
 416
 417/*
 418 * Allocate an extent of length minlen<=len<=maxlen, starting as near
 419 * to bno as possible.  If we don't get maxlen then use prod to trim
 420 * the length, if given.  The lengths are all in rtextents.
 421 */
 422STATIC int				/* error */
 423xfs_rtallocate_extent_near(
 424	xfs_mount_t	*mp,		/* file system mount point */
 425	xfs_trans_t	*tp,		/* transaction pointer */
 426	xfs_rtblock_t	bno,		/* starting block number to allocate */
 427	xfs_extlen_t	minlen,		/* minimum length to allocate */
 428	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 429	xfs_extlen_t	*len,		/* out: actual length allocated */
 430	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 431	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 432	xfs_extlen_t	prod,		/* extent product factor */
 433	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 434{
 435	int		any;		/* any useful extents from summary */
 436	xfs_rtblock_t	bbno;		/* bitmap block number */
 437	int		error;		/* error value */
 438	int		i;		/* bitmap block offset (loop control) */
 439	int		j;		/* secondary loop control */
 440	int		log2len;	/* log2 of minlen */
 441	xfs_rtblock_t	n;		/* next block to try */
 442	xfs_rtblock_t	r;		/* result block */
 443
 444	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 445	/*
 446	 * If the block number given is off the end, silently set it to
 447	 * the last block.
 448	 */
 449	if (bno >= mp->m_sb.sb_rextents)
 450		bno = mp->m_sb.sb_rextents - 1;
 451	/*
 452	 * Try the exact allocation first.
 453	 */
 454	error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen, len,
 455		rbpp, rsb, prod, &r);
 456	if (error) {
 457		return error;
 458	}
 459	/*
 460	 * If the exact allocation worked, return that.
 461	 */
 462	if (r != NULLRTBLOCK) {
 463		*rtblock = r;
 464		return 0;
 465	}
 466	bbno = XFS_BITTOBLOCK(mp, bno);
 467	i = 0;
 468	ASSERT(minlen != 0);
 469	log2len = xfs_highbit32(minlen);
 470	/*
 471	 * Loop over all bitmap blocks (bbno + i is current block).
 472	 */
 473	for (;;) {
 474		/*
 475		 * Get summary information of extents of all useful levels
 476		 * starting in this bitmap block.
 477		 */
 478		error = xfs_rtany_summary(mp, tp, log2len, mp->m_rsumlevels - 1,
 479			bbno + i, rbpp, rsb, &any);
 480		if (error) {
 481			return error;
 482		}
 483		/*
 484		 * If there are any useful extents starting here, try
 485		 * allocating one.
 486		 */
 487		if (any) {
 488			/*
 489			 * On the positive side of the starting location.
 490			 */
 491			if (i >= 0) {
 492				/*
 493				 * Try to allocate an extent starting in
 494				 * this block.
 495				 */
 496				error = xfs_rtallocate_extent_block(mp, tp,
 497					bbno + i, minlen, maxlen, len, &n, rbpp,
 498					rsb, prod, &r);
 499				if (error) {
 500					return error;
 501				}
 502				/*
 503				 * If it worked, return it.
 504				 */
 505				if (r != NULLRTBLOCK) {
 506					*rtblock = r;
 507					return 0;
 508				}
 509			}
 510			/*
 511			 * On the negative side of the starting location.
 512			 */
 513			else {		/* i < 0 */
 514				/*
 515				 * Loop backwards through the bitmap blocks from
 516				 * the starting point-1 up to where we are now.
 517				 * There should be an extent which ends in this
 518				 * bitmap block and is long enough.
 519				 */
 520				for (j = -1; j > i; j--) {
 521					/*
 522					 * Grab the summary information for
 523					 * this bitmap block.
 524					 */
 525					error = xfs_rtany_summary(mp, tp,
 526						log2len, mp->m_rsumlevels - 1,
 527						bbno + j, rbpp, rsb, &any);
 528					if (error) {
 529						return error;
 530					}
 531					/*
 532					 * If there's no extent given in the
 533					 * summary that means the extent we
 534					 * found must carry over from an
 535					 * earlier block.  If there is an
 536					 * extent given, we've already tried
 537					 * that allocation, don't do it again.
 538					 */
 539					if (any)
 540						continue;
 541					error = xfs_rtallocate_extent_block(mp,
 542						tp, bbno + j, minlen, maxlen,
 543						len, &n, rbpp, rsb, prod, &r);
 544					if (error) {
 545						return error;
 546					}
 547					/*
 548					 * If it works, return the extent.
 549					 */
 550					if (r != NULLRTBLOCK) {
 551						*rtblock = r;
 552						return 0;
 553					}
 554				}
 555				/*
 556				 * There weren't intervening bitmap blocks
 557				 * with a long enough extent, or the
 558				 * allocation didn't work for some reason
 559				 * (i.e. it's a little * too short).
 560				 * Try to allocate from the summary block
 561				 * that we found.
 562				 */
 563				error = xfs_rtallocate_extent_block(mp, tp,
 564					bbno + i, minlen, maxlen, len, &n, rbpp,
 565					rsb, prod, &r);
 566				if (error) {
 567					return error;
 568				}
 569				/*
 570				 * If it works, return the extent.
 571				 */
 572				if (r != NULLRTBLOCK) {
 573					*rtblock = r;
 574					return 0;
 575				}
 576			}
 577		}
 578		/*
 579		 * Loop control.  If we were on the positive side, and there's
 580		 * still more blocks on the negative side, go there.
 581		 */
 582		if (i > 0 && (int)bbno - i >= 0)
 583			i = -i;
 584		/*
 585		 * If positive, and no more negative, but there are more
 586		 * positive, go there.
 587		 */
 588		else if (i > 0 && (int)bbno + i < mp->m_sb.sb_rbmblocks - 1)
 589			i++;
 590		/*
 591		 * If negative or 0 (just started), and there are positive
 592		 * blocks to go, go there.  The 0 case moves to block 1.
 593		 */
 594		else if (i <= 0 && (int)bbno - i < mp->m_sb.sb_rbmblocks - 1)
 595			i = 1 - i;
 596		/*
 597		 * If negative or 0 and there are more negative blocks,
 598		 * go there.
 599		 */
 600		else if (i <= 0 && (int)bbno + i > 0)
 601			i--;
 602		/*
 603		 * Must be done.  Return failure.
 604		 */
 605		else
 606			break;
 607	}
 608	*rtblock = NULLRTBLOCK;
 609	return 0;
 610}
 611
 612/*
 613 * Allocate an extent of length minlen<=len<=maxlen, with no position
 614 * specified.  If we don't get maxlen then use prod to trim
 615 * the length, if given.  The lengths are all in rtextents.
 616 */
 617STATIC int				/* error */
 618xfs_rtallocate_extent_size(
 619	xfs_mount_t	*mp,		/* file system mount point */
 620	xfs_trans_t	*tp,		/* transaction pointer */
 621	xfs_extlen_t	minlen,		/* minimum length to allocate */
 622	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 623	xfs_extlen_t	*len,		/* out: actual length allocated */
 624	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 625	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 626	xfs_extlen_t	prod,		/* extent product factor */
 627	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 628{
 629	int		error;		/* error value */
 630	int		i;		/* bitmap block number */
 631	int		l;		/* level number (loop control) */
 632	xfs_rtblock_t	n;		/* next block to be tried */
 633	xfs_rtblock_t	r;		/* result block number */
 634	xfs_suminfo_t	sum;		/* summary information for extents */
 635
 636	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 637	ASSERT(maxlen != 0);
 638
 639	/*
 640	 * Loop over all the levels starting with maxlen.
 641	 * At each level, look at all the bitmap blocks, to see if there
 642	 * are extents starting there that are long enough (>= maxlen).
 643	 * Note, only on the initial level can the allocation fail if
 644	 * the summary says there's an extent.
 645	 */
 646	for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
 647		/*
 648		 * Loop over all the bitmap blocks.
 649		 */
 650		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
 651			/*
 652			 * Get the summary for this level/block.
 653			 */
 654			error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
 655				&sum);
 656			if (error) {
 657				return error;
 658			}
 659			/*
 660			 * Nothing there, on to the next block.
 661			 */
 662			if (!sum)
 663				continue;
 664			/*
 665			 * Try allocating the extent.
 666			 */
 667			error = xfs_rtallocate_extent_block(mp, tp, i, maxlen,
 668				maxlen, len, &n, rbpp, rsb, prod, &r);
 669			if (error) {
 670				return error;
 671			}
 672			/*
 673			 * If it worked, return that.
 674			 */
 675			if (r != NULLRTBLOCK) {
 676				*rtblock = r;
 677				return 0;
 678			}
 679			/*
 680			 * If the "next block to try" returned from the
 681			 * allocator is beyond the next bitmap block,
 682			 * skip to that bitmap block.
 683			 */
 684			if (XFS_BITTOBLOCK(mp, n) > i + 1)
 685				i = XFS_BITTOBLOCK(mp, n) - 1;
 686		}
 687	}
 688	/*
 689	 * Didn't find any maxlen blocks.  Try smaller ones, unless
 690	 * we're asking for a fixed size extent.
 691	 */
 692	if (minlen > --maxlen) {
 693		*rtblock = NULLRTBLOCK;
 694		return 0;
 695	}
 696	ASSERT(minlen != 0);
 697	ASSERT(maxlen != 0);
 698
 699	/*
 700	 * Loop over sizes, from maxlen down to minlen.
 701	 * This time, when we do the allocations, allow smaller ones
 702	 * to succeed.
 703	 */
 704	for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
 705		/*
 706		 * Loop over all the bitmap blocks, try an allocation
 707		 * starting in that block.
 708		 */
 709		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
 710			/*
 711			 * Get the summary information for this level/block.
 712			 */
 713			error =	xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
 714						  &sum);
 715			if (error) {
 716				return error;
 717			}
 718			/*
 719			 * If nothing there, go on to next.
 720			 */
 721			if (!sum)
 722				continue;
 723			/*
 724			 * Try the allocation.  Make sure the specified
 725			 * minlen/maxlen are in the possible range for
 726			 * this summary level.
 727			 */
 728			error = xfs_rtallocate_extent_block(mp, tp, i,
 729					XFS_RTMAX(minlen, 1 << l),
 730					XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
 731					len, &n, rbpp, rsb, prod, &r);
 732			if (error) {
 733				return error;
 734			}
 735			/*
 736			 * If it worked, return that extent.
 737			 */
 738			if (r != NULLRTBLOCK) {
 739				*rtblock = r;
 740				return 0;
 741			}
 742			/*
 743			 * If the "next block to try" returned from the
 744			 * allocator is beyond the next bitmap block,
 745			 * skip to that bitmap block.
 746			 */
 747			if (XFS_BITTOBLOCK(mp, n) > i + 1)
 748				i = XFS_BITTOBLOCK(mp, n) - 1;
 749		}
 750	}
 751	/*
 752	 * Got nothing, return failure.
 753	 */
 754	*rtblock = NULLRTBLOCK;
 755	return 0;
 756}
 757
 758/*
 759 * Allocate space to the bitmap or summary file, and zero it, for growfs.
 760 */
 761STATIC int
 762xfs_growfs_rt_alloc(
 763	struct xfs_mount	*mp,		/* file system mount point */
 764	xfs_extlen_t		oblocks,	/* old count of blocks */
 765	xfs_extlen_t		nblocks,	/* new count of blocks */
 766	struct xfs_inode	*ip)		/* inode (bitmap/summary) */
 767{
 768	xfs_fileoff_t		bno;		/* block number in file */
 769	struct xfs_buf		*bp;	/* temporary buffer for zeroing */
 770	xfs_daddr_t		d;		/* disk block address */
 771	int			error;		/* error return value */
 772	xfs_fsblock_t		firstblock;/* first block allocated in xaction */
 773	struct xfs_defer_ops	dfops;		/* list of freed blocks */
 774	xfs_fsblock_t		fsbno;		/* filesystem block for bno */
 775	struct xfs_bmbt_irec	map;		/* block map output */
 776	int			nmap;		/* number of block maps */
 777	int			resblks;	/* space reservation */
 778	struct xfs_trans	*tp;
 779
 780	/*
 781	 * Allocate space to the file, as necessary.
 782	 */
 783	while (oblocks < nblocks) {
 
 784		resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
 785		/*
 786		 * Reserve space & log for one extent added to the file.
 787		 */
 788		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtalloc, resblks,
 789				0, 0, &tp);
 790		if (error)
 791			return error;
 792		/*
 793		 * Lock the inode.
 794		 */
 795		xfs_ilock(ip, XFS_ILOCK_EXCL);
 796		xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 797
 798		xfs_defer_init(&dfops, &firstblock);
 799		/*
 800		 * Allocate blocks to the bitmap file.
 801		 */
 802		nmap = 1;
 803		error = xfs_bmapi_write(tp, ip, oblocks, nblocks - oblocks,
 804					XFS_BMAPI_METADATA, &firstblock,
 805					resblks, &map, &nmap, &dfops);
 806		if (!error && nmap < 1)
 807			error = -ENOSPC;
 808		if (error)
 809			goto out_bmap_cancel;
 810		/*
 811		 * Free any blocks freed up in the transaction, then commit.
 812		 */
 813		error = xfs_defer_finish(&tp, &dfops);
 814		if (error)
 815			goto out_bmap_cancel;
 816		error = xfs_trans_commit(tp);
 817		if (error)
 818			return error;
 819		/*
 820		 * Now we need to clear the allocated blocks.
 821		 * Do this one block per transaction, to keep it simple.
 822		 */
 823		for (bno = map.br_startoff, fsbno = map.br_startblock;
 824		     bno < map.br_startoff + map.br_blockcount;
 825		     bno++, fsbno++) {
 
 826			/*
 827			 * Reserve log for one block zeroing.
 828			 */
 829			error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtzero,
 830					0, 0, 0, &tp);
 831			if (error)
 832				return error;
 833			/*
 834			 * Lock the bitmap inode.
 835			 */
 836			xfs_ilock(ip, XFS_ILOCK_EXCL);
 837			xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 838			/*
 839			 * Get a buffer for the block.
 840			 */
 841			d = XFS_FSB_TO_DADDR(mp, fsbno);
 842			bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
 843				mp->m_bsize, 0);
 844			if (bp == NULL) {
 845				error = -EIO;
 846				goto out_trans_cancel;
 847			}
 848			memset(bp->b_addr, 0, mp->m_sb.sb_blocksize);
 849			xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
 850			/*
 851			 * Commit the transaction.
 852			 */
 853			error = xfs_trans_commit(tp);
 854			if (error)
 855				return error;
 856		}
 857		/*
 858		 * Go on to the next extent, if any.
 859		 */
 860		oblocks = map.br_startoff + map.br_blockcount;
 861	}
 862
 863	return 0;
 864
 865out_bmap_cancel:
 866	xfs_defer_cancel(&dfops);
 867out_trans_cancel:
 868	xfs_trans_cancel(tp);
 869	return error;
 870}
 871
 872/*
 873 * Visible (exported) functions.
 874 */
 875
 876/*
 877 * Grow the realtime area of the filesystem.
 878 */
 879int
 880xfs_growfs_rt(
 881	xfs_mount_t	*mp,		/* mount point for filesystem */
 882	xfs_growfs_rt_t	*in)		/* growfs rt input struct */
 883{
 884	xfs_rtblock_t	bmbno;		/* bitmap block number */
 885	xfs_buf_t	*bp;		/* temporary buffer */
 886	int		error;		/* error return value */
 887	xfs_mount_t	*nmp;		/* new (fake) mount structure */
 888	xfs_rfsblock_t	nrblocks;	/* new number of realtime blocks */
 889	xfs_extlen_t	nrbmblocks;	/* new number of rt bitmap blocks */
 890	xfs_rtblock_t	nrextents;	/* new number of realtime extents */
 891	uint8_t		nrextslog;	/* new log2 of sb_rextents */
 892	xfs_extlen_t	nrsumblocks;	/* new number of summary blocks */
 893	uint		nrsumlevels;	/* new rt summary levels */
 894	uint		nrsumsize;	/* new size of rt summary, bytes */
 895	xfs_sb_t	*nsbp;		/* new superblock */
 896	xfs_extlen_t	rbmblocks;	/* current number of rt bitmap blocks */
 897	xfs_extlen_t	rsumblocks;	/* current number of rt summary blks */
 898	xfs_sb_t	*sbp;		/* old superblock */
 899	xfs_fsblock_t	sumbno;		/* summary block number */
 900
 901	sbp = &mp->m_sb;
 902	/*
 903	 * Initial error checking.
 904	 */
 905	if (!capable(CAP_SYS_ADMIN))
 906		return -EPERM;
 907	if (mp->m_rtdev_targp == NULL || mp->m_rbmip == NULL ||
 908	    (nrblocks = in->newblocks) <= sbp->sb_rblocks ||
 909	    (sbp->sb_rblocks && (in->extsize != sbp->sb_rextsize)))
 910		return -EINVAL;
 911	if ((error = xfs_sb_validate_fsb_count(sbp, nrblocks)))
 912		return error;
 913	/*
 914	 * Read in the last block of the device, make sure it exists.
 915	 */
 916	error = xfs_buf_read_uncached(mp->m_rtdev_targp,
 917				XFS_FSB_TO_BB(mp, nrblocks - 1),
 918				XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
 919	if (error)
 920		return error;
 921	xfs_buf_relse(bp);
 922
 923	/*
 924	 * Calculate new parameters.  These are the final values to be reached.
 925	 */
 926	nrextents = nrblocks;
 927	do_div(nrextents, in->extsize);
 928	nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize);
 929	nrextslog = xfs_highbit32(nrextents);
 930	nrsumlevels = nrextslog + 1;
 931	nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
 932	nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
 933	nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
 934	/*
 935	 * New summary size can't be more than half the size of
 936	 * the log.  This prevents us from getting a log overflow,
 937	 * since we'll log basically the whole summary file at once.
 938	 */
 939	if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
 940		return -EINVAL;
 941	/*
 942	 * Get the old block counts for bitmap and summary inodes.
 943	 * These can't change since other growfs callers are locked out.
 944	 */
 945	rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_d.di_size);
 946	rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_d.di_size);
 947	/*
 948	 * Allocate space to the bitmap and summary files, as necessary.
 949	 */
 950	error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
 951	if (error)
 952		return error;
 953	error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
 954	if (error)
 955		return error;
 956	/*
 957	 * Allocate a new (fake) mount/sb.
 958	 */
 959	nmp = kmem_alloc(sizeof(*nmp), KM_SLEEP);
 960	/*
 961	 * Loop over the bitmap blocks.
 962	 * We will do everything one bitmap block at a time.
 963	 * Skip the current block if it is exactly full.
 964	 * This also deals with the case where there were no rtextents before.
 965	 */
 966	for (bmbno = sbp->sb_rbmblocks -
 967		     ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
 968	     bmbno < nrbmblocks;
 969	     bmbno++) {
 970		xfs_trans_t	*tp;
 971
 972		*nmp = *mp;
 973		nsbp = &nmp->m_sb;
 974		/*
 975		 * Calculate new sb and mount fields for this round.
 976		 */
 977		nsbp->sb_rextsize = in->extsize;
 978		nsbp->sb_rbmblocks = bmbno + 1;
 979		nsbp->sb_rblocks =
 980			XFS_RTMIN(nrblocks,
 981				  nsbp->sb_rbmblocks * NBBY *
 982				  nsbp->sb_blocksize * nsbp->sb_rextsize);
 983		nsbp->sb_rextents = nsbp->sb_rblocks;
 984		do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
 985		ASSERT(nsbp->sb_rextents != 0);
 986		nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
 987		nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
 988		nrsumsize =
 989			(uint)sizeof(xfs_suminfo_t) * nrsumlevels *
 990			nsbp->sb_rbmblocks;
 991		nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
 992		nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
 993		/*
 994		 * Start a transaction, get the log reservation.
 995		 */
 996		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtfree, 0, 0, 0,
 997				&tp);
 
 998		if (error)
 999			break;
1000		/*
1001		 * Lock out other callers by grabbing the bitmap inode lock.
1002		 */
1003		xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
1004		xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
1005		/*
1006		 * Update the bitmap inode's size.
1007		 */
1008		mp->m_rbmip->i_d.di_size =
1009			nsbp->sb_rbmblocks * nsbp->sb_blocksize;
1010		xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1011		/*
1012		 * Get the summary inode into the transaction.
1013		 */
1014		xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL);
1015		xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
1016		/*
1017		 * Update the summary inode's size.
1018		 */
1019		mp->m_rsumip->i_d.di_size = nmp->m_rsumsize;
1020		xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
1021		/*
1022		 * Copy summary data from old to new sizes.
1023		 * Do this when the real size (not block-aligned) changes.
1024		 */
1025		if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
1026		    mp->m_rsumlevels != nmp->m_rsumlevels) {
1027			error = xfs_rtcopy_summary(mp, nmp, tp);
1028			if (error)
1029				goto error_cancel;
1030		}
1031		/*
1032		 * Update superblock fields.
1033		 */
1034		if (nsbp->sb_rextsize != sbp->sb_rextsize)
1035			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
1036				nsbp->sb_rextsize - sbp->sb_rextsize);
1037		if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
1038			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
1039				nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
1040		if (nsbp->sb_rblocks != sbp->sb_rblocks)
1041			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
1042				nsbp->sb_rblocks - sbp->sb_rblocks);
1043		if (nsbp->sb_rextents != sbp->sb_rextents)
1044			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
1045				nsbp->sb_rextents - sbp->sb_rextents);
1046		if (nsbp->sb_rextslog != sbp->sb_rextslog)
1047			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
1048				nsbp->sb_rextslog - sbp->sb_rextslog);
1049		/*
1050		 * Free new extent.
1051		 */
1052		bp = NULL;
1053		error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
1054			nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
1055		if (error) {
1056error_cancel:
1057			xfs_trans_cancel(tp);
1058			break;
1059		}
1060		/*
1061		 * Mark more blocks free in the superblock.
1062		 */
1063		xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
1064			nsbp->sb_rextents - sbp->sb_rextents);
1065		/*
1066		 * Update mp values into the real mp structure.
1067		 */
1068		mp->m_rsumlevels = nrsumlevels;
1069		mp->m_rsumsize = nrsumsize;
1070
1071		error = xfs_trans_commit(tp);
1072		if (error)
1073			break;
1074	}
1075
1076	/*
1077	 * Free the fake mp structure.
1078	 */
1079	kmem_free(nmp);
1080
1081	return error;
1082}
1083
1084/*
1085 * Allocate an extent in the realtime subvolume, with the usual allocation
1086 * parameters.  The length units are all in realtime extents, as is the
1087 * result block number.
1088 */
1089int					/* error */
1090xfs_rtallocate_extent(
1091	xfs_trans_t	*tp,		/* transaction pointer */
1092	xfs_rtblock_t	bno,		/* starting block number to allocate */
1093	xfs_extlen_t	minlen,		/* minimum length to allocate */
1094	xfs_extlen_t	maxlen,		/* maximum length to allocate */
1095	xfs_extlen_t	*len,		/* out: actual length allocated */
 
1096	int		wasdel,		/* was a delayed allocation extent */
1097	xfs_extlen_t	prod,		/* extent product factor */
1098	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
1099{
1100	xfs_mount_t	*mp = tp->t_mountp;
1101	int		error;		/* error value */
1102	xfs_rtblock_t	r;		/* result allocated block */
1103	xfs_fsblock_t	sb;		/* summary file block number */
1104	xfs_buf_t	*sumbp;		/* summary file block buffer */
1105
1106	ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1107	ASSERT(minlen > 0 && minlen <= maxlen);
1108
1109	/*
1110	 * If prod is set then figure out what to do to minlen and maxlen.
1111	 */
1112	if (prod > 1) {
1113		xfs_extlen_t	i;
1114
1115		if ((i = maxlen % prod))
1116			maxlen -= i;
1117		if ((i = minlen % prod))
1118			minlen += prod - i;
1119		if (maxlen < minlen) {
1120			*rtblock = NULLRTBLOCK;
1121			return 0;
1122		}
1123	}
1124
1125retry:
1126	sumbp = NULL;
1127	if (bno == 0) {
 
 
 
 
1128		error = xfs_rtallocate_extent_size(mp, tp, minlen, maxlen, len,
1129				&sumbp,	&sb, prod, &r);
1130	} else {
 
1131		error = xfs_rtallocate_extent_near(mp, tp, bno, minlen, maxlen,
1132				len, &sumbp, &sb, prod, &r);
 
 
 
 
 
 
 
 
1133	}
1134
1135	if (error)
1136		return error;
1137
1138	/*
1139	 * If it worked, update the superblock.
1140	 */
1141	if (r != NULLRTBLOCK) {
1142		long	slen = (long)*len;
1143
1144		ASSERT(*len >= minlen && *len <= maxlen);
1145		if (wasdel)
1146			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
1147		else
1148			xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
1149	} else if (prod > 1) {
1150		prod = 1;
1151		goto retry;
1152	}
1153
1154	*rtblock = r;
1155	return 0;
1156}
1157
1158/*
1159 * Initialize realtime fields in the mount structure.
1160 */
1161int				/* error */
1162xfs_rtmount_init(
1163	struct xfs_mount	*mp)	/* file system mount structure */
1164{
1165	struct xfs_buf		*bp;	/* buffer for last block of subvolume */
1166	struct xfs_sb		*sbp;	/* filesystem superblock copy in mount */
1167	xfs_daddr_t		d;	/* address of last block of subvolume */
1168	int			error;
1169
1170	sbp = &mp->m_sb;
1171	if (sbp->sb_rblocks == 0)
1172		return 0;
1173	if (mp->m_rtdev_targp == NULL) {
1174		xfs_warn(mp,
1175	"Filesystem has a realtime volume, use rtdev=device option");
1176		return -ENODEV;
1177	}
1178	mp->m_rsumlevels = sbp->sb_rextslog + 1;
1179	mp->m_rsumsize =
1180		(uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
1181		sbp->sb_rbmblocks;
1182	mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
1183	mp->m_rbmip = mp->m_rsumip = NULL;
1184	/*
1185	 * Check that the realtime section is an ok size.
1186	 */
1187	d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
1188	if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
1189		xfs_warn(mp, "realtime mount -- %llu != %llu",
1190			(unsigned long long) XFS_BB_TO_FSB(mp, d),
1191			(unsigned long long) mp->m_sb.sb_rblocks);
1192		return -EFBIG;
1193	}
1194	error = xfs_buf_read_uncached(mp->m_rtdev_targp,
1195					d - XFS_FSB_TO_BB(mp, 1),
1196					XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
1197	if (error) {
1198		xfs_warn(mp, "realtime device size check failed");
1199		return error;
1200	}
1201	xfs_buf_relse(bp);
1202	return 0;
1203}
1204
1205/*
1206 * Get the bitmap and summary inodes into the mount structure
1207 * at mount time.
1208 */
1209int					/* error */
1210xfs_rtmount_inodes(
1211	xfs_mount_t	*mp)		/* file system mount structure */
1212{
1213	int		error;		/* error return value */
1214	xfs_sb_t	*sbp;
1215
1216	sbp = &mp->m_sb;
1217	if (sbp->sb_rbmino == NULLFSINO)
1218		return 0;
1219	error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip);
1220	if (error)
1221		return error;
1222	ASSERT(mp->m_rbmip != NULL);
1223	ASSERT(sbp->sb_rsumino != NULLFSINO);
1224	error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip);
1225	if (error) {
1226		IRELE(mp->m_rbmip);
1227		return error;
1228	}
1229	ASSERT(mp->m_rsumip != NULL);
1230	return 0;
1231}
1232
1233void
1234xfs_rtunmount_inodes(
1235	struct xfs_mount	*mp)
1236{
1237	if (mp->m_rbmip)
1238		IRELE(mp->m_rbmip);
1239	if (mp->m_rsumip)
1240		IRELE(mp->m_rsumip);
1241}
1242
1243/*
1244 * Pick an extent for allocation at the start of a new realtime file.
1245 * Use the sequence number stored in the atime field of the bitmap inode.
1246 * Translate this to a fraction of the rtextents, and return the product
1247 * of rtextents and the fraction.
1248 * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
1249 */
1250int					/* error */
1251xfs_rtpick_extent(
1252	xfs_mount_t	*mp,		/* file system mount point */
1253	xfs_trans_t	*tp,		/* transaction pointer */
1254	xfs_extlen_t	len,		/* allocation length (rtextents) */
1255	xfs_rtblock_t	*pick)		/* result rt extent */
1256{
1257	xfs_rtblock_t	b;		/* result block */
1258	int		log2;		/* log of sequence number */
1259	uint64_t	resid;		/* residual after log removed */
1260	uint64_t	seq;		/* sequence number of file creation */
1261	uint64_t	*seqp;		/* pointer to seqno in inode */
1262
1263	ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1264
1265	seqp = (uint64_t *)&VFS_I(mp->m_rbmip)->i_atime;
1266	if (!(mp->m_rbmip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
1267		mp->m_rbmip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
1268		*seqp = 0;
1269	}
1270	seq = *seqp;
1271	if ((log2 = xfs_highbit64(seq)) == -1)
1272		b = 0;
1273	else {
1274		resid = seq - (1ULL << log2);
1275		b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
1276		    (log2 + 1);
1277		if (b >= mp->m_sb.sb_rextents)
1278			b = do_mod(b, mp->m_sb.sb_rextents);
1279		if (b + len > mp->m_sb.sb_rextents)
1280			b = mp->m_sb.sb_rextents - len;
1281	}
1282	*seqp = seq + 1;
1283	xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1284	*pick = b;
1285	return 0;
1286}
v4.6
   1/*
   2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18#include "xfs.h"
  19#include "xfs_fs.h"
  20#include "xfs_shared.h"
  21#include "xfs_format.h"
  22#include "xfs_log_format.h"
  23#include "xfs_trans_resv.h"
  24#include "xfs_bit.h"
  25#include "xfs_mount.h"
 
  26#include "xfs_inode.h"
  27#include "xfs_bmap.h"
  28#include "xfs_bmap_util.h"
  29#include "xfs_bmap_btree.h"
  30#include "xfs_alloc.h"
  31#include "xfs_error.h"
  32#include "xfs_trans.h"
  33#include "xfs_trans_space.h"
  34#include "xfs_trace.h"
  35#include "xfs_buf.h"
  36#include "xfs_icache.h"
  37#include "xfs_rtalloc.h"
  38
  39
  40/*
  41 * Read and return the summary information for a given extent size,
  42 * bitmap block combination.
  43 * Keeps track of a current summary block, so we don't keep reading
  44 * it from the buffer cache.
  45 */
  46static int
  47xfs_rtget_summary(
  48	xfs_mount_t	*mp,		/* file system mount structure */
  49	xfs_trans_t	*tp,		/* transaction pointer */
  50	int		log,		/* log2 of extent size */
  51	xfs_rtblock_t	bbno,		/* bitmap block number */
  52	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
  53	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
  54	xfs_suminfo_t	*sum)		/* out: summary info for this block */
  55{
  56	return xfs_rtmodify_summary_int(mp, tp, log, bbno, 0, rbpp, rsb, sum);
  57}
  58
  59/*
  60 * Return whether there are any free extents in the size range given
  61 * by low and high, for the bitmap block bbno.
  62 */
  63STATIC int				/* error */
  64xfs_rtany_summary(
  65	xfs_mount_t	*mp,		/* file system mount structure */
  66	xfs_trans_t	*tp,		/* transaction pointer */
  67	int		low,		/* low log2 extent size */
  68	int		high,		/* high log2 extent size */
  69	xfs_rtblock_t	bbno,		/* bitmap block number */
  70	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
  71	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
  72	int		*stat)		/* out: any good extents here? */
  73{
  74	int		error;		/* error value */
  75	int		log;		/* loop counter, log2 of ext. size */
  76	xfs_suminfo_t	sum;		/* summary data */
  77
  78	/*
  79	 * Loop over logs of extent sizes.  Order is irrelevant.
  80	 */
  81	for (log = low; log <= high; log++) {
  82		/*
  83		 * Get one summary datum.
  84		 */
  85		error = xfs_rtget_summary(mp, tp, log, bbno, rbpp, rsb, &sum);
  86		if (error) {
  87			return error;
  88		}
  89		/*
  90		 * If there are any, return success.
  91		 */
  92		if (sum) {
  93			*stat = 1;
  94			return 0;
  95		}
  96	}
  97	/*
  98	 * Found nothing, return failure.
  99	 */
 100	*stat = 0;
 101	return 0;
 102}
 103
 104
 105/*
 106 * Copy and transform the summary file, given the old and new
 107 * parameters in the mount structures.
 108 */
 109STATIC int				/* error */
 110xfs_rtcopy_summary(
 111	xfs_mount_t	*omp,		/* old file system mount point */
 112	xfs_mount_t	*nmp,		/* new file system mount point */
 113	xfs_trans_t	*tp)		/* transaction pointer */
 114{
 115	xfs_rtblock_t	bbno;		/* bitmap block number */
 116	xfs_buf_t	*bp;		/* summary buffer */
 117	int		error;		/* error return value */
 118	int		log;		/* summary level number (log length) */
 119	xfs_suminfo_t	sum;		/* summary data */
 120	xfs_fsblock_t	sumbno;		/* summary block number */
 121
 122	bp = NULL;
 123	for (log = omp->m_rsumlevels - 1; log >= 0; log--) {
 124		for (bbno = omp->m_sb.sb_rbmblocks - 1;
 125		     (xfs_srtblock_t)bbno >= 0;
 126		     bbno--) {
 127			error = xfs_rtget_summary(omp, tp, log, bbno, &bp,
 128				&sumbno, &sum);
 129			if (error)
 130				return error;
 131			if (sum == 0)
 132				continue;
 133			error = xfs_rtmodify_summary(omp, tp, log, bbno, -sum,
 134				&bp, &sumbno);
 135			if (error)
 136				return error;
 137			error = xfs_rtmodify_summary(nmp, tp, log, bbno, sum,
 138				&bp, &sumbno);
 139			if (error)
 140				return error;
 141			ASSERT(sum > 0);
 142		}
 143	}
 144	return 0;
 145}
 146/*
 147 * Mark an extent specified by start and len allocated.
 148 * Updates all the summary information as well as the bitmap.
 149 */
 150STATIC int				/* error */
 151xfs_rtallocate_range(
 152	xfs_mount_t	*mp,		/* file system mount point */
 153	xfs_trans_t	*tp,		/* transaction pointer */
 154	xfs_rtblock_t	start,		/* start block to allocate */
 155	xfs_extlen_t	len,		/* length to allocate */
 156	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 157	xfs_fsblock_t	*rsb)		/* in/out: summary block number */
 158{
 159	xfs_rtblock_t	end;		/* end of the allocated extent */
 160	int		error;		/* error value */
 161	xfs_rtblock_t	postblock = 0;	/* first block allocated > end */
 162	xfs_rtblock_t	preblock = 0;	/* first block allocated < start */
 163
 164	end = start + len - 1;
 165	/*
 166	 * Assume we're allocating out of the middle of a free extent.
 167	 * We need to find the beginning and end of the extent so we can
 168	 * properly update the summary.
 169	 */
 170	error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
 171	if (error) {
 172		return error;
 173	}
 174	/*
 175	 * Find the next allocated block (end of free extent).
 176	 */
 177	error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
 178		&postblock);
 179	if (error) {
 180		return error;
 181	}
 182	/*
 183	 * Decrement the summary information corresponding to the entire
 184	 * (old) free extent.
 185	 */
 186	error = xfs_rtmodify_summary(mp, tp,
 187		XFS_RTBLOCKLOG(postblock + 1 - preblock),
 188		XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
 189	if (error) {
 190		return error;
 191	}
 192	/*
 193	 * If there are blocks not being allocated at the front of the
 194	 * old extent, add summary data for them to be free.
 195	 */
 196	if (preblock < start) {
 197		error = xfs_rtmodify_summary(mp, tp,
 198			XFS_RTBLOCKLOG(start - preblock),
 199			XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
 200		if (error) {
 201			return error;
 202		}
 203	}
 204	/*
 205	 * If there are blocks not being allocated at the end of the
 206	 * old extent, add summary data for them to be free.
 207	 */
 208	if (postblock > end) {
 209		error = xfs_rtmodify_summary(mp, tp,
 210			XFS_RTBLOCKLOG(postblock - end),
 211			XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
 212		if (error) {
 213			return error;
 214		}
 215	}
 216	/*
 217	 * Modify the bitmap to mark this extent allocated.
 218	 */
 219	error = xfs_rtmodify_range(mp, tp, start, len, 0);
 220	return error;
 221}
 222
 223/*
 224 * Attempt to allocate an extent minlen<=len<=maxlen starting from
 225 * bitmap block bbno.  If we don't get maxlen then use prod to trim
 226 * the length, if given.  Returns error; returns starting block in *rtblock.
 227 * The lengths are all in rtextents.
 228 */
 229STATIC int				/* error */
 230xfs_rtallocate_extent_block(
 231	xfs_mount_t	*mp,		/* file system mount point */
 232	xfs_trans_t	*tp,		/* transaction pointer */
 233	xfs_rtblock_t	bbno,		/* bitmap block number */
 234	xfs_extlen_t	minlen,		/* minimum length to allocate */
 235	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 236	xfs_extlen_t	*len,		/* out: actual length allocated */
 237	xfs_rtblock_t	*nextp,		/* out: next block to try */
 238	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 239	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 240	xfs_extlen_t	prod,		/* extent product factor */
 241	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 242{
 243	xfs_rtblock_t	besti;		/* best rtblock found so far */
 244	xfs_rtblock_t	bestlen;	/* best length found so far */
 245	xfs_rtblock_t	end;		/* last rtblock in chunk */
 246	int		error;		/* error value */
 247	xfs_rtblock_t	i;		/* current rtblock trying */
 248	xfs_rtblock_t	next;		/* next rtblock to try */
 249	int		stat;		/* status from internal calls */
 250
 251	/*
 252	 * Loop over all the extents starting in this bitmap block,
 253	 * looking for one that's long enough.
 254	 */
 255	for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
 256		end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
 257	     i <= end;
 258	     i++) {
 259		/*
 260		 * See if there's a free extent of maxlen starting at i.
 261		 * If it's not so then next will contain the first non-free.
 262		 */
 263		error = xfs_rtcheck_range(mp, tp, i, maxlen, 1, &next, &stat);
 264		if (error) {
 265			return error;
 266		}
 267		if (stat) {
 268			/*
 269			 * i for maxlen is all free, allocate and return that.
 270			 */
 271			error = xfs_rtallocate_range(mp, tp, i, maxlen, rbpp,
 272				rsb);
 273			if (error) {
 274				return error;
 275			}
 276			*len = maxlen;
 277			*rtblock = i;
 278			return 0;
 279		}
 280		/*
 281		 * In the case where we have a variable-sized allocation
 282		 * request, figure out how big this free piece is,
 283		 * and if it's big enough for the minimum, and the best
 284		 * so far, remember it.
 285		 */
 286		if (minlen < maxlen) {
 287			xfs_rtblock_t	thislen;	/* this extent size */
 288
 289			thislen = next - i;
 290			if (thislen >= minlen && thislen > bestlen) {
 291				besti = i;
 292				bestlen = thislen;
 293			}
 294		}
 295		/*
 296		 * If not done yet, find the start of the next free space.
 297		 */
 298		if (next < end) {
 299			error = xfs_rtfind_forw(mp, tp, next, end, &i);
 300			if (error) {
 301				return error;
 302			}
 303		} else
 304			break;
 305	}
 306	/*
 307	 * Searched the whole thing & didn't find a maxlen free extent.
 308	 */
 309	if (minlen < maxlen && besti != -1) {
 310		xfs_extlen_t	p;	/* amount to trim length by */
 311
 312		/*
 313		 * If size should be a multiple of prod, make that so.
 314		 */
 315		if (prod > 1 && (p = do_mod(bestlen, prod)))
 316			bestlen -= p;
 317		/*
 318		 * Allocate besti for bestlen & return that.
 319		 */
 320		error = xfs_rtallocate_range(mp, tp, besti, bestlen, rbpp, rsb);
 321		if (error) {
 322			return error;
 323		}
 324		*len = bestlen;
 325		*rtblock = besti;
 326		return 0;
 327	}
 328	/*
 329	 * Allocation failed.  Set *nextp to the next block to try.
 330	 */
 331	*nextp = next;
 332	*rtblock = NULLRTBLOCK;
 333	return 0;
 334}
 335
 336/*
 337 * Allocate an extent of length minlen<=len<=maxlen, starting at block
 338 * bno.  If we don't get maxlen then use prod to trim the length, if given.
 339 * Returns error; returns starting block in *rtblock.
 340 * The lengths are all in rtextents.
 341 */
 342STATIC int				/* error */
 343xfs_rtallocate_extent_exact(
 344	xfs_mount_t	*mp,		/* file system mount point */
 345	xfs_trans_t	*tp,		/* transaction pointer */
 346	xfs_rtblock_t	bno,		/* starting block number to allocate */
 347	xfs_extlen_t	minlen,		/* minimum length to allocate */
 348	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 349	xfs_extlen_t	*len,		/* out: actual length allocated */
 350	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 351	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 352	xfs_extlen_t	prod,		/* extent product factor */
 353	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 354{
 355	int		error;		/* error value */
 356	xfs_extlen_t	i;		/* extent length trimmed due to prod */
 357	int		isfree;		/* extent is free */
 358	xfs_rtblock_t	next;		/* next block to try (dummy) */
 359
 360	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 361	/*
 362	 * Check if the range in question (for maxlen) is free.
 363	 */
 364	error = xfs_rtcheck_range(mp, tp, bno, maxlen, 1, &next, &isfree);
 365	if (error) {
 366		return error;
 367	}
 368	if (isfree) {
 369		/*
 370		 * If it is, allocate it and return success.
 371		 */
 372		error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
 373		if (error) {
 374			return error;
 375		}
 376		*len = maxlen;
 377		*rtblock = bno;
 378		return 0;
 379	}
 380	/*
 381	 * If not, allocate what there is, if it's at least minlen.
 382	 */
 383	maxlen = next - bno;
 384	if (maxlen < minlen) {
 385		/*
 386		 * Failed, return failure status.
 387		 */
 388		*rtblock = NULLRTBLOCK;
 389		return 0;
 390	}
 391	/*
 392	 * Trim off tail of extent, if prod is specified.
 393	 */
 394	if (prod > 1 && (i = maxlen % prod)) {
 395		maxlen -= i;
 396		if (maxlen < minlen) {
 397			/*
 398			 * Now we can't do it, return failure status.
 399			 */
 400			*rtblock = NULLRTBLOCK;
 401			return 0;
 402		}
 403	}
 404	/*
 405	 * Allocate what we can and return it.
 406	 */
 407	error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
 408	if (error) {
 409		return error;
 410	}
 411	*len = maxlen;
 412	*rtblock = bno;
 413	return 0;
 414}
 415
 416/*
 417 * Allocate an extent of length minlen<=len<=maxlen, starting as near
 418 * to bno as possible.  If we don't get maxlen then use prod to trim
 419 * the length, if given.  The lengths are all in rtextents.
 420 */
 421STATIC int				/* error */
 422xfs_rtallocate_extent_near(
 423	xfs_mount_t	*mp,		/* file system mount point */
 424	xfs_trans_t	*tp,		/* transaction pointer */
 425	xfs_rtblock_t	bno,		/* starting block number to allocate */
 426	xfs_extlen_t	minlen,		/* minimum length to allocate */
 427	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 428	xfs_extlen_t	*len,		/* out: actual length allocated */
 429	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 430	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 431	xfs_extlen_t	prod,		/* extent product factor */
 432	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 433{
 434	int		any;		/* any useful extents from summary */
 435	xfs_rtblock_t	bbno;		/* bitmap block number */
 436	int		error;		/* error value */
 437	int		i;		/* bitmap block offset (loop control) */
 438	int		j;		/* secondary loop control */
 439	int		log2len;	/* log2 of minlen */
 440	xfs_rtblock_t	n;		/* next block to try */
 441	xfs_rtblock_t	r;		/* result block */
 442
 443	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 444	/*
 445	 * If the block number given is off the end, silently set it to
 446	 * the last block.
 447	 */
 448	if (bno >= mp->m_sb.sb_rextents)
 449		bno = mp->m_sb.sb_rextents - 1;
 450	/*
 451	 * Try the exact allocation first.
 452	 */
 453	error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen, len,
 454		rbpp, rsb, prod, &r);
 455	if (error) {
 456		return error;
 457	}
 458	/*
 459	 * If the exact allocation worked, return that.
 460	 */
 461	if (r != NULLRTBLOCK) {
 462		*rtblock = r;
 463		return 0;
 464	}
 465	bbno = XFS_BITTOBLOCK(mp, bno);
 466	i = 0;
 467	ASSERT(minlen != 0);
 468	log2len = xfs_highbit32(minlen);
 469	/*
 470	 * Loop over all bitmap blocks (bbno + i is current block).
 471	 */
 472	for (;;) {
 473		/*
 474		 * Get summary information of extents of all useful levels
 475		 * starting in this bitmap block.
 476		 */
 477		error = xfs_rtany_summary(mp, tp, log2len, mp->m_rsumlevels - 1,
 478			bbno + i, rbpp, rsb, &any);
 479		if (error) {
 480			return error;
 481		}
 482		/*
 483		 * If there are any useful extents starting here, try
 484		 * allocating one.
 485		 */
 486		if (any) {
 487			/*
 488			 * On the positive side of the starting location.
 489			 */
 490			if (i >= 0) {
 491				/*
 492				 * Try to allocate an extent starting in
 493				 * this block.
 494				 */
 495				error = xfs_rtallocate_extent_block(mp, tp,
 496					bbno + i, minlen, maxlen, len, &n, rbpp,
 497					rsb, prod, &r);
 498				if (error) {
 499					return error;
 500				}
 501				/*
 502				 * If it worked, return it.
 503				 */
 504				if (r != NULLRTBLOCK) {
 505					*rtblock = r;
 506					return 0;
 507				}
 508			}
 509			/*
 510			 * On the negative side of the starting location.
 511			 */
 512			else {		/* i < 0 */
 513				/*
 514				 * Loop backwards through the bitmap blocks from
 515				 * the starting point-1 up to where we are now.
 516				 * There should be an extent which ends in this
 517				 * bitmap block and is long enough.
 518				 */
 519				for (j = -1; j > i; j--) {
 520					/*
 521					 * Grab the summary information for
 522					 * this bitmap block.
 523					 */
 524					error = xfs_rtany_summary(mp, tp,
 525						log2len, mp->m_rsumlevels - 1,
 526						bbno + j, rbpp, rsb, &any);
 527					if (error) {
 528						return error;
 529					}
 530					/*
 531					 * If there's no extent given in the
 532					 * summary that means the extent we
 533					 * found must carry over from an
 534					 * earlier block.  If there is an
 535					 * extent given, we've already tried
 536					 * that allocation, don't do it again.
 537					 */
 538					if (any)
 539						continue;
 540					error = xfs_rtallocate_extent_block(mp,
 541						tp, bbno + j, minlen, maxlen,
 542						len, &n, rbpp, rsb, prod, &r);
 543					if (error) {
 544						return error;
 545					}
 546					/*
 547					 * If it works, return the extent.
 548					 */
 549					if (r != NULLRTBLOCK) {
 550						*rtblock = r;
 551						return 0;
 552					}
 553				}
 554				/*
 555				 * There weren't intervening bitmap blocks
 556				 * with a long enough extent, or the
 557				 * allocation didn't work for some reason
 558				 * (i.e. it's a little * too short).
 559				 * Try to allocate from the summary block
 560				 * that we found.
 561				 */
 562				error = xfs_rtallocate_extent_block(mp, tp,
 563					bbno + i, minlen, maxlen, len, &n, rbpp,
 564					rsb, prod, &r);
 565				if (error) {
 566					return error;
 567				}
 568				/*
 569				 * If it works, return the extent.
 570				 */
 571				if (r != NULLRTBLOCK) {
 572					*rtblock = r;
 573					return 0;
 574				}
 575			}
 576		}
 577		/*
 578		 * Loop control.  If we were on the positive side, and there's
 579		 * still more blocks on the negative side, go there.
 580		 */
 581		if (i > 0 && (int)bbno - i >= 0)
 582			i = -i;
 583		/*
 584		 * If positive, and no more negative, but there are more
 585		 * positive, go there.
 586		 */
 587		else if (i > 0 && (int)bbno + i < mp->m_sb.sb_rbmblocks - 1)
 588			i++;
 589		/*
 590		 * If negative or 0 (just started), and there are positive
 591		 * blocks to go, go there.  The 0 case moves to block 1.
 592		 */
 593		else if (i <= 0 && (int)bbno - i < mp->m_sb.sb_rbmblocks - 1)
 594			i = 1 - i;
 595		/*
 596		 * If negative or 0 and there are more negative blocks,
 597		 * go there.
 598		 */
 599		else if (i <= 0 && (int)bbno + i > 0)
 600			i--;
 601		/*
 602		 * Must be done.  Return failure.
 603		 */
 604		else
 605			break;
 606	}
 607	*rtblock = NULLRTBLOCK;
 608	return 0;
 609}
 610
 611/*
 612 * Allocate an extent of length minlen<=len<=maxlen, with no position
 613 * specified.  If we don't get maxlen then use prod to trim
 614 * the length, if given.  The lengths are all in rtextents.
 615 */
 616STATIC int				/* error */
 617xfs_rtallocate_extent_size(
 618	xfs_mount_t	*mp,		/* file system mount point */
 619	xfs_trans_t	*tp,		/* transaction pointer */
 620	xfs_extlen_t	minlen,		/* minimum length to allocate */
 621	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 622	xfs_extlen_t	*len,		/* out: actual length allocated */
 623	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 624	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 625	xfs_extlen_t	prod,		/* extent product factor */
 626	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 627{
 628	int		error;		/* error value */
 629	int		i;		/* bitmap block number */
 630	int		l;		/* level number (loop control) */
 631	xfs_rtblock_t	n;		/* next block to be tried */
 632	xfs_rtblock_t	r;		/* result block number */
 633	xfs_suminfo_t	sum;		/* summary information for extents */
 634
 635	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 636	ASSERT(maxlen != 0);
 637
 638	/*
 639	 * Loop over all the levels starting with maxlen.
 640	 * At each level, look at all the bitmap blocks, to see if there
 641	 * are extents starting there that are long enough (>= maxlen).
 642	 * Note, only on the initial level can the allocation fail if
 643	 * the summary says there's an extent.
 644	 */
 645	for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
 646		/*
 647		 * Loop over all the bitmap blocks.
 648		 */
 649		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
 650			/*
 651			 * Get the summary for this level/block.
 652			 */
 653			error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
 654				&sum);
 655			if (error) {
 656				return error;
 657			}
 658			/*
 659			 * Nothing there, on to the next block.
 660			 */
 661			if (!sum)
 662				continue;
 663			/*
 664			 * Try allocating the extent.
 665			 */
 666			error = xfs_rtallocate_extent_block(mp, tp, i, maxlen,
 667				maxlen, len, &n, rbpp, rsb, prod, &r);
 668			if (error) {
 669				return error;
 670			}
 671			/*
 672			 * If it worked, return that.
 673			 */
 674			if (r != NULLRTBLOCK) {
 675				*rtblock = r;
 676				return 0;
 677			}
 678			/*
 679			 * If the "next block to try" returned from the
 680			 * allocator is beyond the next bitmap block,
 681			 * skip to that bitmap block.
 682			 */
 683			if (XFS_BITTOBLOCK(mp, n) > i + 1)
 684				i = XFS_BITTOBLOCK(mp, n) - 1;
 685		}
 686	}
 687	/*
 688	 * Didn't find any maxlen blocks.  Try smaller ones, unless
 689	 * we're asking for a fixed size extent.
 690	 */
 691	if (minlen > --maxlen) {
 692		*rtblock = NULLRTBLOCK;
 693		return 0;
 694	}
 695	ASSERT(minlen != 0);
 696	ASSERT(maxlen != 0);
 697
 698	/*
 699	 * Loop over sizes, from maxlen down to minlen.
 700	 * This time, when we do the allocations, allow smaller ones
 701	 * to succeed.
 702	 */
 703	for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
 704		/*
 705		 * Loop over all the bitmap blocks, try an allocation
 706		 * starting in that block.
 707		 */
 708		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
 709			/*
 710			 * Get the summary information for this level/block.
 711			 */
 712			error =	xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
 713						  &sum);
 714			if (error) {
 715				return error;
 716			}
 717			/*
 718			 * If nothing there, go on to next.
 719			 */
 720			if (!sum)
 721				continue;
 722			/*
 723			 * Try the allocation.  Make sure the specified
 724			 * minlen/maxlen are in the possible range for
 725			 * this summary level.
 726			 */
 727			error = xfs_rtallocate_extent_block(mp, tp, i,
 728					XFS_RTMAX(minlen, 1 << l),
 729					XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
 730					len, &n, rbpp, rsb, prod, &r);
 731			if (error) {
 732				return error;
 733			}
 734			/*
 735			 * If it worked, return that extent.
 736			 */
 737			if (r != NULLRTBLOCK) {
 738				*rtblock = r;
 739				return 0;
 740			}
 741			/*
 742			 * If the "next block to try" returned from the
 743			 * allocator is beyond the next bitmap block,
 744			 * skip to that bitmap block.
 745			 */
 746			if (XFS_BITTOBLOCK(mp, n) > i + 1)
 747				i = XFS_BITTOBLOCK(mp, n) - 1;
 748		}
 749	}
 750	/*
 751	 * Got nothing, return failure.
 752	 */
 753	*rtblock = NULLRTBLOCK;
 754	return 0;
 755}
 756
 757/*
 758 * Allocate space to the bitmap or summary file, and zero it, for growfs.
 759 */
 760STATIC int
 761xfs_growfs_rt_alloc(
 762	struct xfs_mount	*mp,		/* file system mount point */
 763	xfs_extlen_t		oblocks,	/* old count of blocks */
 764	xfs_extlen_t		nblocks,	/* new count of blocks */
 765	struct xfs_inode	*ip)		/* inode (bitmap/summary) */
 766{
 767	xfs_fileoff_t		bno;		/* block number in file */
 768	struct xfs_buf		*bp;	/* temporary buffer for zeroing */
 769	xfs_daddr_t		d;		/* disk block address */
 770	int			error;		/* error return value */
 771	xfs_fsblock_t		firstblock;/* first block allocated in xaction */
 772	struct xfs_bmap_free	flist;		/* list of freed blocks */
 773	xfs_fsblock_t		fsbno;		/* filesystem block for bno */
 774	struct xfs_bmbt_irec	map;		/* block map output */
 775	int			nmap;		/* number of block maps */
 776	int			resblks;	/* space reservation */
 777	struct xfs_trans	*tp;
 778
 779	/*
 780	 * Allocate space to the file, as necessary.
 781	 */
 782	while (oblocks < nblocks) {
 783		tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_ALLOC);
 784		resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
 785		/*
 786		 * Reserve space & log for one extent added to the file.
 787		 */
 788		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_growrtalloc,
 789					  resblks, 0);
 790		if (error)
 791			goto out_trans_cancel;
 792		/*
 793		 * Lock the inode.
 794		 */
 795		xfs_ilock(ip, XFS_ILOCK_EXCL);
 796		xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 797
 798		xfs_bmap_init(&flist, &firstblock);
 799		/*
 800		 * Allocate blocks to the bitmap file.
 801		 */
 802		nmap = 1;
 803		error = xfs_bmapi_write(tp, ip, oblocks, nblocks - oblocks,
 804					XFS_BMAPI_METADATA, &firstblock,
 805					resblks, &map, &nmap, &flist);
 806		if (!error && nmap < 1)
 807			error = -ENOSPC;
 808		if (error)
 809			goto out_bmap_cancel;
 810		/*
 811		 * Free any blocks freed up in the transaction, then commit.
 812		 */
 813		error = xfs_bmap_finish(&tp, &flist, NULL);
 814		if (error)
 815			goto out_bmap_cancel;
 816		error = xfs_trans_commit(tp);
 817		if (error)
 818			return error;
 819		/*
 820		 * Now we need to clear the allocated blocks.
 821		 * Do this one block per transaction, to keep it simple.
 822		 */
 823		for (bno = map.br_startoff, fsbno = map.br_startblock;
 824		     bno < map.br_startoff + map.br_blockcount;
 825		     bno++, fsbno++) {
 826			tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_ZERO);
 827			/*
 828			 * Reserve log for one block zeroing.
 829			 */
 830			error = xfs_trans_reserve(tp, &M_RES(mp)->tr_growrtzero,
 831						  0, 0);
 832			if (error)
 833				goto out_trans_cancel;
 834			/*
 835			 * Lock the bitmap inode.
 836			 */
 837			xfs_ilock(ip, XFS_ILOCK_EXCL);
 838			xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 839			/*
 840			 * Get a buffer for the block.
 841			 */
 842			d = XFS_FSB_TO_DADDR(mp, fsbno);
 843			bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
 844				mp->m_bsize, 0);
 845			if (bp == NULL) {
 846				error = -EIO;
 847				goto out_trans_cancel;
 848			}
 849			memset(bp->b_addr, 0, mp->m_sb.sb_blocksize);
 850			xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
 851			/*
 852			 * Commit the transaction.
 853			 */
 854			error = xfs_trans_commit(tp);
 855			if (error)
 856				return error;
 857		}
 858		/*
 859		 * Go on to the next extent, if any.
 860		 */
 861		oblocks = map.br_startoff + map.br_blockcount;
 862	}
 863
 864	return 0;
 865
 866out_bmap_cancel:
 867	xfs_bmap_cancel(&flist);
 868out_trans_cancel:
 869	xfs_trans_cancel(tp);
 870	return error;
 871}
 872
 873/*
 874 * Visible (exported) functions.
 875 */
 876
 877/*
 878 * Grow the realtime area of the filesystem.
 879 */
 880int
 881xfs_growfs_rt(
 882	xfs_mount_t	*mp,		/* mount point for filesystem */
 883	xfs_growfs_rt_t	*in)		/* growfs rt input struct */
 884{
 885	xfs_rtblock_t	bmbno;		/* bitmap block number */
 886	xfs_buf_t	*bp;		/* temporary buffer */
 887	int		error;		/* error return value */
 888	xfs_mount_t	*nmp;		/* new (fake) mount structure */
 889	xfs_rfsblock_t	nrblocks;	/* new number of realtime blocks */
 890	xfs_extlen_t	nrbmblocks;	/* new number of rt bitmap blocks */
 891	xfs_rtblock_t	nrextents;	/* new number of realtime extents */
 892	uint8_t		nrextslog;	/* new log2 of sb_rextents */
 893	xfs_extlen_t	nrsumblocks;	/* new number of summary blocks */
 894	uint		nrsumlevels;	/* new rt summary levels */
 895	uint		nrsumsize;	/* new size of rt summary, bytes */
 896	xfs_sb_t	*nsbp;		/* new superblock */
 897	xfs_extlen_t	rbmblocks;	/* current number of rt bitmap blocks */
 898	xfs_extlen_t	rsumblocks;	/* current number of rt summary blks */
 899	xfs_sb_t	*sbp;		/* old superblock */
 900	xfs_fsblock_t	sumbno;		/* summary block number */
 901
 902	sbp = &mp->m_sb;
 903	/*
 904	 * Initial error checking.
 905	 */
 906	if (!capable(CAP_SYS_ADMIN))
 907		return -EPERM;
 908	if (mp->m_rtdev_targp == NULL || mp->m_rbmip == NULL ||
 909	    (nrblocks = in->newblocks) <= sbp->sb_rblocks ||
 910	    (sbp->sb_rblocks && (in->extsize != sbp->sb_rextsize)))
 911		return -EINVAL;
 912	if ((error = xfs_sb_validate_fsb_count(sbp, nrblocks)))
 913		return error;
 914	/*
 915	 * Read in the last block of the device, make sure it exists.
 916	 */
 917	error = xfs_buf_read_uncached(mp->m_rtdev_targp,
 918				XFS_FSB_TO_BB(mp, nrblocks - 1),
 919				XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
 920	if (error)
 921		return error;
 922	xfs_buf_relse(bp);
 923
 924	/*
 925	 * Calculate new parameters.  These are the final values to be reached.
 926	 */
 927	nrextents = nrblocks;
 928	do_div(nrextents, in->extsize);
 929	nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize);
 930	nrextslog = xfs_highbit32(nrextents);
 931	nrsumlevels = nrextslog + 1;
 932	nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
 933	nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
 934	nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
 935	/*
 936	 * New summary size can't be more than half the size of
 937	 * the log.  This prevents us from getting a log overflow,
 938	 * since we'll log basically the whole summary file at once.
 939	 */
 940	if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
 941		return -EINVAL;
 942	/*
 943	 * Get the old block counts for bitmap and summary inodes.
 944	 * These can't change since other growfs callers are locked out.
 945	 */
 946	rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_d.di_size);
 947	rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_d.di_size);
 948	/*
 949	 * Allocate space to the bitmap and summary files, as necessary.
 950	 */
 951	error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
 952	if (error)
 953		return error;
 954	error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
 955	if (error)
 956		return error;
 957	/*
 958	 * Allocate a new (fake) mount/sb.
 959	 */
 960	nmp = kmem_alloc(sizeof(*nmp), KM_SLEEP);
 961	/*
 962	 * Loop over the bitmap blocks.
 963	 * We will do everything one bitmap block at a time.
 964	 * Skip the current block if it is exactly full.
 965	 * This also deals with the case where there were no rtextents before.
 966	 */
 967	for (bmbno = sbp->sb_rbmblocks -
 968		     ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
 969	     bmbno < nrbmblocks;
 970	     bmbno++) {
 971		xfs_trans_t	*tp;
 972
 973		*nmp = *mp;
 974		nsbp = &nmp->m_sb;
 975		/*
 976		 * Calculate new sb and mount fields for this round.
 977		 */
 978		nsbp->sb_rextsize = in->extsize;
 979		nsbp->sb_rbmblocks = bmbno + 1;
 980		nsbp->sb_rblocks =
 981			XFS_RTMIN(nrblocks,
 982				  nsbp->sb_rbmblocks * NBBY *
 983				  nsbp->sb_blocksize * nsbp->sb_rextsize);
 984		nsbp->sb_rextents = nsbp->sb_rblocks;
 985		do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
 986		ASSERT(nsbp->sb_rextents != 0);
 987		nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
 988		nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
 989		nrsumsize =
 990			(uint)sizeof(xfs_suminfo_t) * nrsumlevels *
 991			nsbp->sb_rbmblocks;
 992		nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
 993		nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
 994		/*
 995		 * Start a transaction, get the log reservation.
 996		 */
 997		tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_FREE);
 998		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_growrtfree,
 999					  0, 0);
1000		if (error)
1001			goto error_cancel;
1002		/*
1003		 * Lock out other callers by grabbing the bitmap inode lock.
1004		 */
1005		xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
1006		xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
1007		/*
1008		 * Update the bitmap inode's size.
1009		 */
1010		mp->m_rbmip->i_d.di_size =
1011			nsbp->sb_rbmblocks * nsbp->sb_blocksize;
1012		xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1013		/*
1014		 * Get the summary inode into the transaction.
1015		 */
1016		xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL);
1017		xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
1018		/*
1019		 * Update the summary inode's size.
1020		 */
1021		mp->m_rsumip->i_d.di_size = nmp->m_rsumsize;
1022		xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
1023		/*
1024		 * Copy summary data from old to new sizes.
1025		 * Do this when the real size (not block-aligned) changes.
1026		 */
1027		if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
1028		    mp->m_rsumlevels != nmp->m_rsumlevels) {
1029			error = xfs_rtcopy_summary(mp, nmp, tp);
1030			if (error)
1031				goto error_cancel;
1032		}
1033		/*
1034		 * Update superblock fields.
1035		 */
1036		if (nsbp->sb_rextsize != sbp->sb_rextsize)
1037			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
1038				nsbp->sb_rextsize - sbp->sb_rextsize);
1039		if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
1040			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
1041				nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
1042		if (nsbp->sb_rblocks != sbp->sb_rblocks)
1043			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
1044				nsbp->sb_rblocks - sbp->sb_rblocks);
1045		if (nsbp->sb_rextents != sbp->sb_rextents)
1046			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
1047				nsbp->sb_rextents - sbp->sb_rextents);
1048		if (nsbp->sb_rextslog != sbp->sb_rextslog)
1049			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
1050				nsbp->sb_rextslog - sbp->sb_rextslog);
1051		/*
1052		 * Free new extent.
1053		 */
1054		bp = NULL;
1055		error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
1056			nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
1057		if (error) {
1058error_cancel:
1059			xfs_trans_cancel(tp);
1060			break;
1061		}
1062		/*
1063		 * Mark more blocks free in the superblock.
1064		 */
1065		xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
1066			nsbp->sb_rextents - sbp->sb_rextents);
1067		/*
1068		 * Update mp values into the real mp structure.
1069		 */
1070		mp->m_rsumlevels = nrsumlevels;
1071		mp->m_rsumsize = nrsumsize;
1072
1073		error = xfs_trans_commit(tp);
1074		if (error)
1075			break;
1076	}
1077
1078	/*
1079	 * Free the fake mp structure.
1080	 */
1081	kmem_free(nmp);
1082
1083	return error;
1084}
1085
1086/*
1087 * Allocate an extent in the realtime subvolume, with the usual allocation
1088 * parameters.  The length units are all in realtime extents, as is the
1089 * result block number.
1090 */
1091int					/* error */
1092xfs_rtallocate_extent(
1093	xfs_trans_t	*tp,		/* transaction pointer */
1094	xfs_rtblock_t	bno,		/* starting block number to allocate */
1095	xfs_extlen_t	minlen,		/* minimum length to allocate */
1096	xfs_extlen_t	maxlen,		/* maximum length to allocate */
1097	xfs_extlen_t	*len,		/* out: actual length allocated */
1098	xfs_alloctype_t	type,		/* allocation type XFS_ALLOCTYPE... */
1099	int		wasdel,		/* was a delayed allocation extent */
1100	xfs_extlen_t	prod,		/* extent product factor */
1101	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
1102{
1103	xfs_mount_t	*mp = tp->t_mountp;
1104	int		error;		/* error value */
1105	xfs_rtblock_t	r;		/* result allocated block */
1106	xfs_fsblock_t	sb;		/* summary file block number */
1107	xfs_buf_t	*sumbp;		/* summary file block buffer */
1108
1109	ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1110	ASSERT(minlen > 0 && minlen <= maxlen);
1111
1112	/*
1113	 * If prod is set then figure out what to do to minlen and maxlen.
1114	 */
1115	if (prod > 1) {
1116		xfs_extlen_t	i;
1117
1118		if ((i = maxlen % prod))
1119			maxlen -= i;
1120		if ((i = minlen % prod))
1121			minlen += prod - i;
1122		if (maxlen < minlen) {
1123			*rtblock = NULLRTBLOCK;
1124			return 0;
1125		}
1126	}
1127
 
1128	sumbp = NULL;
1129	/*
1130	 * Allocate by size, or near another block, or exactly at some block.
1131	 */
1132	switch (type) {
1133	case XFS_ALLOCTYPE_ANY_AG:
1134		error = xfs_rtallocate_extent_size(mp, tp, minlen, maxlen, len,
1135				&sumbp,	&sb, prod, &r);
1136		break;
1137	case XFS_ALLOCTYPE_NEAR_BNO:
1138		error = xfs_rtallocate_extent_near(mp, tp, bno, minlen, maxlen,
1139				len, &sumbp, &sb, prod, &r);
1140		break;
1141	case XFS_ALLOCTYPE_THIS_BNO:
1142		error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen,
1143				len, &sumbp, &sb, prod, &r);
1144		break;
1145	default:
1146		error = -EIO;
1147		ASSERT(0);
1148	}
 
1149	if (error)
1150		return error;
1151
1152	/*
1153	 * If it worked, update the superblock.
1154	 */
1155	if (r != NULLRTBLOCK) {
1156		long	slen = (long)*len;
1157
1158		ASSERT(*len >= minlen && *len <= maxlen);
1159		if (wasdel)
1160			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
1161		else
1162			xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
 
 
 
1163	}
 
1164	*rtblock = r;
1165	return 0;
1166}
1167
1168/*
1169 * Initialize realtime fields in the mount structure.
1170 */
1171int				/* error */
1172xfs_rtmount_init(
1173	struct xfs_mount	*mp)	/* file system mount structure */
1174{
1175	struct xfs_buf		*bp;	/* buffer for last block of subvolume */
1176	struct xfs_sb		*sbp;	/* filesystem superblock copy in mount */
1177	xfs_daddr_t		d;	/* address of last block of subvolume */
1178	int			error;
1179
1180	sbp = &mp->m_sb;
1181	if (sbp->sb_rblocks == 0)
1182		return 0;
1183	if (mp->m_rtdev_targp == NULL) {
1184		xfs_warn(mp,
1185	"Filesystem has a realtime volume, use rtdev=device option");
1186		return -ENODEV;
1187	}
1188	mp->m_rsumlevels = sbp->sb_rextslog + 1;
1189	mp->m_rsumsize =
1190		(uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
1191		sbp->sb_rbmblocks;
1192	mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
1193	mp->m_rbmip = mp->m_rsumip = NULL;
1194	/*
1195	 * Check that the realtime section is an ok size.
1196	 */
1197	d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
1198	if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
1199		xfs_warn(mp, "realtime mount -- %llu != %llu",
1200			(unsigned long long) XFS_BB_TO_FSB(mp, d),
1201			(unsigned long long) mp->m_sb.sb_rblocks);
1202		return -EFBIG;
1203	}
1204	error = xfs_buf_read_uncached(mp->m_rtdev_targp,
1205					d - XFS_FSB_TO_BB(mp, 1),
1206					XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
1207	if (error) {
1208		xfs_warn(mp, "realtime device size check failed");
1209		return error;
1210	}
1211	xfs_buf_relse(bp);
1212	return 0;
1213}
1214
1215/*
1216 * Get the bitmap and summary inodes into the mount structure
1217 * at mount time.
1218 */
1219int					/* error */
1220xfs_rtmount_inodes(
1221	xfs_mount_t	*mp)		/* file system mount structure */
1222{
1223	int		error;		/* error return value */
1224	xfs_sb_t	*sbp;
1225
1226	sbp = &mp->m_sb;
1227	if (sbp->sb_rbmino == NULLFSINO)
1228		return 0;
1229	error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip);
1230	if (error)
1231		return error;
1232	ASSERT(mp->m_rbmip != NULL);
1233	ASSERT(sbp->sb_rsumino != NULLFSINO);
1234	error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip);
1235	if (error) {
1236		IRELE(mp->m_rbmip);
1237		return error;
1238	}
1239	ASSERT(mp->m_rsumip != NULL);
1240	return 0;
1241}
1242
1243void
1244xfs_rtunmount_inodes(
1245	struct xfs_mount	*mp)
1246{
1247	if (mp->m_rbmip)
1248		IRELE(mp->m_rbmip);
1249	if (mp->m_rsumip)
1250		IRELE(mp->m_rsumip);
1251}
1252
1253/*
1254 * Pick an extent for allocation at the start of a new realtime file.
1255 * Use the sequence number stored in the atime field of the bitmap inode.
1256 * Translate this to a fraction of the rtextents, and return the product
1257 * of rtextents and the fraction.
1258 * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
1259 */
1260int					/* error */
1261xfs_rtpick_extent(
1262	xfs_mount_t	*mp,		/* file system mount point */
1263	xfs_trans_t	*tp,		/* transaction pointer */
1264	xfs_extlen_t	len,		/* allocation length (rtextents) */
1265	xfs_rtblock_t	*pick)		/* result rt extent */
1266{
1267	xfs_rtblock_t	b;		/* result block */
1268	int		log2;		/* log of sequence number */
1269	__uint64_t	resid;		/* residual after log removed */
1270	__uint64_t	seq;		/* sequence number of file creation */
1271	__uint64_t	*seqp;		/* pointer to seqno in inode */
1272
1273	ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1274
1275	seqp = (__uint64_t *)&VFS_I(mp->m_rbmip)->i_atime;
1276	if (!(mp->m_rbmip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
1277		mp->m_rbmip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
1278		*seqp = 0;
1279	}
1280	seq = *seqp;
1281	if ((log2 = xfs_highbit64(seq)) == -1)
1282		b = 0;
1283	else {
1284		resid = seq - (1ULL << log2);
1285		b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
1286		    (log2 + 1);
1287		if (b >= mp->m_sb.sb_rextents)
1288			b = do_mod(b, mp->m_sb.sb_rextents);
1289		if (b + len > mp->m_sb.sb_rextents)
1290			b = mp->m_sb.sb_rextents - len;
1291	}
1292	*seqp = seq + 1;
1293	xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1294	*pick = b;
1295	return 0;
1296}