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v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   4 * All Rights Reserved.
   5 */
   6#include "xfs.h"
   7#include "xfs_fs.h"
   8#include "xfs_shared.h"
   9#include "xfs_format.h"
  10#include "xfs_log_format.h"
  11#include "xfs_trans_resv.h"
  12#include "xfs_bit.h"
  13#include "xfs_mount.h"
  14#include "xfs_inode.h"
  15#include "xfs_bmap.h"
  16#include "xfs_bmap_btree.h"
  17#include "xfs_trans.h"
  18#include "xfs_trans_space.h"
  19#include "xfs_icache.h"
  20#include "xfs_rtalloc.h"
  21
  22
  23/*
  24 * Read and return the summary information for a given extent size,
  25 * bitmap block combination.
  26 * Keeps track of a current summary block, so we don't keep reading
  27 * it from the buffer cache.
  28 */
  29static int
  30xfs_rtget_summary(
  31	xfs_mount_t	*mp,		/* file system mount structure */
  32	xfs_trans_t	*tp,		/* transaction pointer */
  33	int		log,		/* log2 of extent size */
  34	xfs_rtblock_t	bbno,		/* bitmap block number */
  35	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
  36	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
  37	xfs_suminfo_t	*sum)		/* out: summary info for this block */
  38{
  39	return xfs_rtmodify_summary_int(mp, tp, log, bbno, 0, rbpp, rsb, sum);
  40}
  41
  42/*
  43 * Return whether there are any free extents in the size range given
  44 * by low and high, for the bitmap block bbno.
  45 */
  46STATIC int				/* error */
  47xfs_rtany_summary(
  48	xfs_mount_t	*mp,		/* file system mount structure */
  49	xfs_trans_t	*tp,		/* transaction pointer */
  50	int		low,		/* low log2 extent size */
  51	int		high,		/* high log2 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	int		*stat)		/* out: any good extents here? */
  56{
  57	int		error;		/* error value */
  58	int		log;		/* loop counter, log2 of ext. size */
  59	xfs_suminfo_t	sum;		/* summary data */
  60
  61	/* There are no extents at levels < m_rsum_cache[bbno]. */
  62	if (mp->m_rsum_cache && low < mp->m_rsum_cache[bbno])
  63		low = mp->m_rsum_cache[bbno];
  64
  65	/*
  66	 * Loop over logs of extent sizes.
  67	 */
  68	for (log = low; log <= high; log++) {
  69		/*
  70		 * Get one summary datum.
  71		 */
  72		error = xfs_rtget_summary(mp, tp, log, bbno, rbpp, rsb, &sum);
  73		if (error) {
  74			return error;
  75		}
  76		/*
  77		 * If there are any, return success.
  78		 */
  79		if (sum) {
  80			*stat = 1;
  81			goto out;
  82		}
  83	}
  84	/*
  85	 * Found nothing, return failure.
  86	 */
  87	*stat = 0;
  88out:
  89	/* There were no extents at levels < log. */
  90	if (mp->m_rsum_cache && log > mp->m_rsum_cache[bbno])
  91		mp->m_rsum_cache[bbno] = log;
  92	return 0;
  93}
  94
  95
  96/*
  97 * Copy and transform the summary file, given the old and new
  98 * parameters in the mount structures.
  99 */
 100STATIC int				/* error */
 101xfs_rtcopy_summary(
 102	xfs_mount_t	*omp,		/* old file system mount point */
 103	xfs_mount_t	*nmp,		/* new file system mount point */
 104	xfs_trans_t	*tp)		/* transaction pointer */
 105{
 106	xfs_rtblock_t	bbno;		/* bitmap block number */
 107	xfs_buf_t	*bp;		/* summary buffer */
 108	int		error;		/* error return value */
 109	int		log;		/* summary level number (log length) */
 110	xfs_suminfo_t	sum;		/* summary data */
 111	xfs_fsblock_t	sumbno;		/* summary block number */
 112
 113	bp = NULL;
 114	for (log = omp->m_rsumlevels - 1; log >= 0; log--) {
 115		for (bbno = omp->m_sb.sb_rbmblocks - 1;
 116		     (xfs_srtblock_t)bbno >= 0;
 117		     bbno--) {
 118			error = xfs_rtget_summary(omp, tp, log, bbno, &bp,
 119				&sumbno, &sum);
 120			if (error)
 121				return error;
 122			if (sum == 0)
 123				continue;
 124			error = xfs_rtmodify_summary(omp, tp, log, bbno, -sum,
 125				&bp, &sumbno);
 126			if (error)
 127				return error;
 128			error = xfs_rtmodify_summary(nmp, tp, log, bbno, sum,
 129				&bp, &sumbno);
 130			if (error)
 131				return error;
 132			ASSERT(sum > 0);
 133		}
 134	}
 135	return 0;
 136}
 137/*
 138 * Mark an extent specified by start and len allocated.
 139 * Updates all the summary information as well as the bitmap.
 140 */
 141STATIC int				/* error */
 142xfs_rtallocate_range(
 143	xfs_mount_t	*mp,		/* file system mount point */
 144	xfs_trans_t	*tp,		/* transaction pointer */
 145	xfs_rtblock_t	start,		/* start block to allocate */
 146	xfs_extlen_t	len,		/* length to allocate */
 147	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 148	xfs_fsblock_t	*rsb)		/* in/out: summary block number */
 149{
 150	xfs_rtblock_t	end;		/* end of the allocated extent */
 151	int		error;		/* error value */
 152	xfs_rtblock_t	postblock = 0;	/* first block allocated > end */
 153	xfs_rtblock_t	preblock = 0;	/* first block allocated < start */
 154
 155	end = start + len - 1;
 156	/*
 157	 * Assume we're allocating out of the middle of a free extent.
 158	 * We need to find the beginning and end of the extent so we can
 159	 * properly update the summary.
 160	 */
 161	error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
 162	if (error) {
 163		return error;
 164	}
 165	/*
 166	 * Find the next allocated block (end of free extent).
 167	 */
 168	error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
 169		&postblock);
 170	if (error) {
 171		return error;
 172	}
 173	/*
 174	 * Decrement the summary information corresponding to the entire
 175	 * (old) free extent.
 176	 */
 177	error = xfs_rtmodify_summary(mp, tp,
 178		XFS_RTBLOCKLOG(postblock + 1 - preblock),
 179		XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
 180	if (error) {
 181		return error;
 182	}
 183	/*
 184	 * If there are blocks not being allocated at the front of the
 185	 * old extent, add summary data for them to be free.
 186	 */
 187	if (preblock < start) {
 188		error = xfs_rtmodify_summary(mp, tp,
 189			XFS_RTBLOCKLOG(start - preblock),
 190			XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
 191		if (error) {
 192			return error;
 193		}
 194	}
 195	/*
 196	 * If there are blocks not being allocated at the end of the
 197	 * old extent, add summary data for them to be free.
 198	 */
 199	if (postblock > end) {
 200		error = xfs_rtmodify_summary(mp, tp,
 201			XFS_RTBLOCKLOG(postblock - end),
 202			XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
 203		if (error) {
 204			return error;
 205		}
 206	}
 207	/*
 208	 * Modify the bitmap to mark this extent allocated.
 209	 */
 210	error = xfs_rtmodify_range(mp, tp, start, len, 0);
 211	return error;
 212}
 213
 214/*
 215 * Attempt to allocate an extent minlen<=len<=maxlen starting from
 216 * bitmap block bbno.  If we don't get maxlen then use prod to trim
 217 * the length, if given.  Returns error; returns starting block in *rtblock.
 218 * The lengths are all in rtextents.
 219 */
 220STATIC int				/* error */
 221xfs_rtallocate_extent_block(
 222	xfs_mount_t	*mp,		/* file system mount point */
 223	xfs_trans_t	*tp,		/* transaction pointer */
 224	xfs_rtblock_t	bbno,		/* bitmap block number */
 225	xfs_extlen_t	minlen,		/* minimum length to allocate */
 226	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 227	xfs_extlen_t	*len,		/* out: actual length allocated */
 228	xfs_rtblock_t	*nextp,		/* out: next block to try */
 229	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 230	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 231	xfs_extlen_t	prod,		/* extent product factor */
 232	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 233{
 234	xfs_rtblock_t	besti;		/* best rtblock found so far */
 235	xfs_rtblock_t	bestlen;	/* best length found so far */
 236	xfs_rtblock_t	end;		/* last rtblock in chunk */
 237	int		error;		/* error value */
 238	xfs_rtblock_t	i;		/* current rtblock trying */
 239	xfs_rtblock_t	next;		/* next rtblock to try */
 240	int		stat;		/* status from internal calls */
 241
 242	/*
 243	 * Loop over all the extents starting in this bitmap block,
 244	 * looking for one that's long enough.
 245	 */
 246	for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
 247		end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
 248	     i <= end;
 249	     i++) {
 
 
 
 250		/*
 251		 * See if there's a free extent of maxlen starting at i.
 252		 * If it's not so then next will contain the first non-free.
 253		 */
 254		error = xfs_rtcheck_range(mp, tp, i, maxlen, 1, &next, &stat);
 255		if (error) {
 256			return error;
 257		}
 258		if (stat) {
 259			/*
 260			 * i for maxlen is all free, allocate and return that.
 261			 */
 262			error = xfs_rtallocate_range(mp, tp, i, maxlen, rbpp,
 263				rsb);
 264			if (error) {
 265				return error;
 266			}
 267			*len = maxlen;
 268			*rtblock = i;
 269			return 0;
 270		}
 271		/*
 272		 * In the case where we have a variable-sized allocation
 273		 * request, figure out how big this free piece is,
 274		 * and if it's big enough for the minimum, and the best
 275		 * so far, remember it.
 276		 */
 277		if (minlen < maxlen) {
 278			xfs_rtblock_t	thislen;	/* this extent size */
 279
 280			thislen = next - i;
 281			if (thislen >= minlen && thislen > bestlen) {
 282				besti = i;
 283				bestlen = thislen;
 284			}
 285		}
 286		/*
 287		 * If not done yet, find the start of the next free space.
 288		 */
 289		if (next < end) {
 290			error = xfs_rtfind_forw(mp, tp, next, end, &i);
 291			if (error) {
 292				return error;
 293			}
 294		} else
 295			break;
 296	}
 297	/*
 298	 * Searched the whole thing & didn't find a maxlen free extent.
 299	 */
 300	if (minlen < maxlen && besti != -1) {
 301		xfs_extlen_t	p;	/* amount to trim length by */
 302
 303		/*
 304		 * If size should be a multiple of prod, make that so.
 305		 */
 306		if (prod > 1) {
 307			div_u64_rem(bestlen, prod, &p);
 308			if (p)
 309				bestlen -= p;
 310		}
 311
 312		/*
 313		 * Allocate besti for bestlen & return that.
 314		 */
 315		error = xfs_rtallocate_range(mp, tp, besti, bestlen, rbpp, rsb);
 316		if (error) {
 317			return error;
 318		}
 319		*len = bestlen;
 320		*rtblock = besti;
 321		return 0;
 322	}
 323	/*
 324	 * Allocation failed.  Set *nextp to the next block to try.
 325	 */
 326	*nextp = next;
 327	*rtblock = NULLRTBLOCK;
 328	return 0;
 329}
 330
 331/*
 332 * Allocate an extent of length minlen<=len<=maxlen, starting at block
 333 * bno.  If we don't get maxlen then use prod to trim the length, if given.
 334 * Returns error; returns starting block in *rtblock.
 335 * The lengths are all in rtextents.
 336 */
 337STATIC int				/* error */
 338xfs_rtallocate_extent_exact(
 339	xfs_mount_t	*mp,		/* file system mount point */
 340	xfs_trans_t	*tp,		/* transaction pointer */
 341	xfs_rtblock_t	bno,		/* starting block number to allocate */
 342	xfs_extlen_t	minlen,		/* minimum length to allocate */
 343	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 344	xfs_extlen_t	*len,		/* out: actual length allocated */
 345	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 346	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 347	xfs_extlen_t	prod,		/* extent product factor */
 348	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 349{
 350	int		error;		/* error value */
 351	xfs_extlen_t	i;		/* extent length trimmed due to prod */
 352	int		isfree;		/* extent is free */
 353	xfs_rtblock_t	next;		/* next block to try (dummy) */
 354
 355	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 356	/*
 357	 * Check if the range in question (for maxlen) is free.
 358	 */
 359	error = xfs_rtcheck_range(mp, tp, bno, maxlen, 1, &next, &isfree);
 360	if (error) {
 361		return error;
 362	}
 363	if (isfree) {
 364		/*
 365		 * If it is, allocate it and return success.
 366		 */
 367		error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
 368		if (error) {
 369			return error;
 370		}
 371		*len = maxlen;
 372		*rtblock = bno;
 373		return 0;
 374	}
 375	/*
 376	 * If not, allocate what there is, if it's at least minlen.
 377	 */
 378	maxlen = next - bno;
 379	if (maxlen < minlen) {
 380		/*
 381		 * Failed, return failure status.
 382		 */
 383		*rtblock = NULLRTBLOCK;
 384		return 0;
 385	}
 386	/*
 387	 * Trim off tail of extent, if prod is specified.
 388	 */
 389	if (prod > 1 && (i = maxlen % prod)) {
 390		maxlen -= i;
 391		if (maxlen < minlen) {
 392			/*
 393			 * Now we can't do it, return failure status.
 394			 */
 395			*rtblock = NULLRTBLOCK;
 396			return 0;
 397		}
 398	}
 399	/*
 400	 * Allocate what we can and return it.
 401	 */
 402	error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
 403	if (error) {
 404		return error;
 405	}
 406	*len = maxlen;
 407	*rtblock = bno;
 408	return 0;
 409}
 410
 411/*
 412 * Allocate an extent of length minlen<=len<=maxlen, starting as near
 413 * to bno as possible.  If we don't get maxlen then use prod to trim
 414 * the length, if given.  The lengths are all in rtextents.
 415 */
 416STATIC int				/* error */
 417xfs_rtallocate_extent_near(
 418	xfs_mount_t	*mp,		/* file system mount point */
 419	xfs_trans_t	*tp,		/* transaction pointer */
 420	xfs_rtblock_t	bno,		/* starting block number to allocate */
 421	xfs_extlen_t	minlen,		/* minimum length to allocate */
 422	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 423	xfs_extlen_t	*len,		/* out: actual length allocated */
 424	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 425	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 426	xfs_extlen_t	prod,		/* extent product factor */
 427	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 428{
 429	int		any;		/* any useful extents from summary */
 430	xfs_rtblock_t	bbno;		/* bitmap block number */
 431	int		error;		/* error value */
 432	int		i;		/* bitmap block offset (loop control) */
 433	int		j;		/* secondary loop control */
 434	int		log2len;	/* log2 of minlen */
 435	xfs_rtblock_t	n;		/* next block to try */
 436	xfs_rtblock_t	r;		/* result block */
 437
 438	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 439	/*
 440	 * If the block number given is off the end, silently set it to
 441	 * the last block.
 442	 */
 443	if (bno >= mp->m_sb.sb_rextents)
 444		bno = mp->m_sb.sb_rextents - 1;
 
 
 
 
 
 
 
 
 445	/*
 446	 * Try the exact allocation first.
 447	 */
 448	error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen, len,
 449		rbpp, rsb, prod, &r);
 450	if (error) {
 451		return error;
 452	}
 453	/*
 454	 * If the exact allocation worked, return that.
 455	 */
 456	if (r != NULLRTBLOCK) {
 457		*rtblock = r;
 458		return 0;
 459	}
 460	bbno = XFS_BITTOBLOCK(mp, bno);
 461	i = 0;
 462	ASSERT(minlen != 0);
 463	log2len = xfs_highbit32(minlen);
 464	/*
 465	 * Loop over all bitmap blocks (bbno + i is current block).
 466	 */
 467	for (;;) {
 468		/*
 469		 * Get summary information of extents of all useful levels
 470		 * starting in this bitmap block.
 471		 */
 472		error = xfs_rtany_summary(mp, tp, log2len, mp->m_rsumlevels - 1,
 473			bbno + i, rbpp, rsb, &any);
 474		if (error) {
 475			return error;
 476		}
 477		/*
 478		 * If there are any useful extents starting here, try
 479		 * allocating one.
 480		 */
 481		if (any) {
 482			/*
 483			 * On the positive side of the starting location.
 484			 */
 485			if (i >= 0) {
 486				/*
 487				 * Try to allocate an extent starting in
 488				 * this block.
 489				 */
 490				error = xfs_rtallocate_extent_block(mp, tp,
 491					bbno + i, minlen, maxlen, len, &n, rbpp,
 492					rsb, prod, &r);
 493				if (error) {
 494					return error;
 495				}
 496				/*
 497				 * If it worked, return it.
 498				 */
 499				if (r != NULLRTBLOCK) {
 500					*rtblock = r;
 501					return 0;
 502				}
 503			}
 504			/*
 505			 * On the negative side of the starting location.
 506			 */
 507			else {		/* i < 0 */
 508				/*
 509				 * Loop backwards through the bitmap blocks from
 510				 * the starting point-1 up to where we are now.
 511				 * There should be an extent which ends in this
 512				 * bitmap block and is long enough.
 513				 */
 514				for (j = -1; j > i; j--) {
 515					/*
 516					 * Grab the summary information for
 517					 * this bitmap block.
 518					 */
 519					error = xfs_rtany_summary(mp, tp,
 520						log2len, mp->m_rsumlevels - 1,
 521						bbno + j, rbpp, rsb, &any);
 522					if (error) {
 523						return error;
 524					}
 525					/*
 526					 * If there's no extent given in the
 527					 * summary that means the extent we
 528					 * found must carry over from an
 529					 * earlier block.  If there is an
 530					 * extent given, we've already tried
 531					 * that allocation, don't do it again.
 532					 */
 533					if (any)
 534						continue;
 535					error = xfs_rtallocate_extent_block(mp,
 536						tp, bbno + j, minlen, maxlen,
 537						len, &n, rbpp, rsb, prod, &r);
 538					if (error) {
 539						return error;
 540					}
 541					/*
 542					 * If it works, return the extent.
 543					 */
 544					if (r != NULLRTBLOCK) {
 545						*rtblock = r;
 546						return 0;
 547					}
 548				}
 549				/*
 550				 * There weren't intervening bitmap blocks
 551				 * with a long enough extent, or the
 552				 * allocation didn't work for some reason
 553				 * (i.e. it's a little * too short).
 554				 * Try to allocate from the summary block
 555				 * that we found.
 556				 */
 557				error = xfs_rtallocate_extent_block(mp, tp,
 558					bbno + i, minlen, maxlen, len, &n, rbpp,
 559					rsb, prod, &r);
 560				if (error) {
 561					return error;
 562				}
 563				/*
 564				 * If it works, return the extent.
 565				 */
 566				if (r != NULLRTBLOCK) {
 567					*rtblock = r;
 568					return 0;
 569				}
 570			}
 571		}
 572		/*
 573		 * Loop control.  If we were on the positive side, and there's
 574		 * still more blocks on the negative side, go there.
 575		 */
 576		if (i > 0 && (int)bbno - i >= 0)
 577			i = -i;
 578		/*
 579		 * If positive, and no more negative, but there are more
 580		 * positive, go there.
 581		 */
 582		else if (i > 0 && (int)bbno + i < mp->m_sb.sb_rbmblocks - 1)
 583			i++;
 584		/*
 585		 * If negative or 0 (just started), and there are positive
 586		 * blocks to go, go there.  The 0 case moves to block 1.
 587		 */
 588		else if (i <= 0 && (int)bbno - i < mp->m_sb.sb_rbmblocks - 1)
 589			i = 1 - i;
 590		/*
 591		 * If negative or 0 and there are more negative blocks,
 592		 * go there.
 593		 */
 594		else if (i <= 0 && (int)bbno + i > 0)
 595			i--;
 596		/*
 597		 * Must be done.  Return failure.
 598		 */
 599		else
 600			break;
 601	}
 602	*rtblock = NULLRTBLOCK;
 603	return 0;
 604}
 605
 606/*
 607 * Allocate an extent of length minlen<=len<=maxlen, with no position
 608 * specified.  If we don't get maxlen then use prod to trim
 609 * the length, if given.  The lengths are all in rtextents.
 610 */
 611STATIC int				/* error */
 612xfs_rtallocate_extent_size(
 613	xfs_mount_t	*mp,		/* file system mount point */
 614	xfs_trans_t	*tp,		/* transaction pointer */
 615	xfs_extlen_t	minlen,		/* minimum length to allocate */
 616	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 617	xfs_extlen_t	*len,		/* out: actual length allocated */
 618	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
 619	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 620	xfs_extlen_t	prod,		/* extent product factor */
 621	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 622{
 623	int		error;		/* error value */
 624	int		i;		/* bitmap block number */
 625	int		l;		/* level number (loop control) */
 626	xfs_rtblock_t	n;		/* next block to be tried */
 627	xfs_rtblock_t	r;		/* result block number */
 628	xfs_suminfo_t	sum;		/* summary information for extents */
 629
 630	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 631	ASSERT(maxlen != 0);
 632
 633	/*
 634	 * Loop over all the levels starting with maxlen.
 635	 * At each level, look at all the bitmap blocks, to see if there
 636	 * are extents starting there that are long enough (>= maxlen).
 637	 * Note, only on the initial level can the allocation fail if
 638	 * the summary says there's an extent.
 639	 */
 640	for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
 641		/*
 642		 * Loop over all the bitmap blocks.
 643		 */
 644		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
 645			/*
 646			 * Get the summary for this level/block.
 647			 */
 648			error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
 649				&sum);
 650			if (error) {
 651				return error;
 652			}
 653			/*
 654			 * Nothing there, on to the next block.
 655			 */
 656			if (!sum)
 657				continue;
 658			/*
 659			 * Try allocating the extent.
 660			 */
 661			error = xfs_rtallocate_extent_block(mp, tp, i, maxlen,
 662				maxlen, len, &n, rbpp, rsb, prod, &r);
 663			if (error) {
 664				return error;
 665			}
 666			/*
 667			 * If it worked, return that.
 668			 */
 669			if (r != NULLRTBLOCK) {
 670				*rtblock = r;
 671				return 0;
 672			}
 673			/*
 674			 * If the "next block to try" returned from the
 675			 * allocator is beyond the next bitmap block,
 676			 * skip to that bitmap block.
 677			 */
 678			if (XFS_BITTOBLOCK(mp, n) > i + 1)
 679				i = XFS_BITTOBLOCK(mp, n) - 1;
 680		}
 681	}
 682	/*
 683	 * Didn't find any maxlen blocks.  Try smaller ones, unless
 684	 * we're asking for a fixed size extent.
 685	 */
 686	if (minlen > --maxlen) {
 687		*rtblock = NULLRTBLOCK;
 688		return 0;
 689	}
 690	ASSERT(minlen != 0);
 691	ASSERT(maxlen != 0);
 692
 693	/*
 694	 * Loop over sizes, from maxlen down to minlen.
 695	 * This time, when we do the allocations, allow smaller ones
 696	 * to succeed.
 697	 */
 698	for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
 699		/*
 700		 * Loop over all the bitmap blocks, try an allocation
 701		 * starting in that block.
 702		 */
 703		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
 704			/*
 705			 * Get the summary information for this level/block.
 706			 */
 707			error =	xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
 708						  &sum);
 709			if (error) {
 710				return error;
 711			}
 712			/*
 713			 * If nothing there, go on to next.
 714			 */
 715			if (!sum)
 716				continue;
 717			/*
 718			 * Try the allocation.  Make sure the specified
 719			 * minlen/maxlen are in the possible range for
 720			 * this summary level.
 721			 */
 722			error = xfs_rtallocate_extent_block(mp, tp, i,
 723					XFS_RTMAX(minlen, 1 << l),
 724					XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
 725					len, &n, rbpp, rsb, prod, &r);
 726			if (error) {
 727				return error;
 728			}
 729			/*
 730			 * If it worked, return that extent.
 731			 */
 732			if (r != NULLRTBLOCK) {
 733				*rtblock = r;
 734				return 0;
 735			}
 736			/*
 737			 * If the "next block to try" returned from the
 738			 * allocator is beyond the next bitmap block,
 739			 * skip to that bitmap block.
 740			 */
 741			if (XFS_BITTOBLOCK(mp, n) > i + 1)
 742				i = XFS_BITTOBLOCK(mp, n) - 1;
 743		}
 744	}
 745	/*
 746	 * Got nothing, return failure.
 747	 */
 748	*rtblock = NULLRTBLOCK;
 749	return 0;
 750}
 751
 752/*
 753 * Allocate space to the bitmap or summary file, and zero it, for growfs.
 754 */
 755STATIC int
 756xfs_growfs_rt_alloc(
 757	struct xfs_mount	*mp,		/* file system mount point */
 758	xfs_extlen_t		oblocks,	/* old count of blocks */
 759	xfs_extlen_t		nblocks,	/* new count of blocks */
 760	struct xfs_inode	*ip)		/* inode (bitmap/summary) */
 761{
 762	xfs_fileoff_t		bno;		/* block number in file */
 763	struct xfs_buf		*bp;	/* temporary buffer for zeroing */
 764	xfs_daddr_t		d;		/* disk block address */
 765	int			error;		/* error return value */
 766	xfs_fsblock_t		fsbno;		/* filesystem block for bno */
 767	struct xfs_bmbt_irec	map;		/* block map output */
 768	int			nmap;		/* number of block maps */
 769	int			resblks;	/* space reservation */
 
 770	struct xfs_trans	*tp;
 771
 
 
 
 
 
 772	/*
 773	 * Allocate space to the file, as necessary.
 774	 */
 775	while (oblocks < nblocks) {
 776		resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
 777		/*
 778		 * Reserve space & log for one extent added to the file.
 779		 */
 780		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtalloc, resblks,
 781				0, 0, &tp);
 782		if (error)
 783			return error;
 784		/*
 785		 * Lock the inode.
 786		 */
 787		xfs_ilock(ip, XFS_ILOCK_EXCL);
 788		xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 789
 
 
 
 
 
 790		/*
 791		 * Allocate blocks to the bitmap file.
 792		 */
 793		nmap = 1;
 794		error = xfs_bmapi_write(tp, ip, oblocks, nblocks - oblocks,
 795					XFS_BMAPI_METADATA, resblks, &map,
 796					&nmap);
 797		if (!error && nmap < 1)
 798			error = -ENOSPC;
 799		if (error)
 800			goto out_trans_cancel;
 801		/*
 802		 * Free any blocks freed up in the transaction, then commit.
 803		 */
 804		error = xfs_trans_commit(tp);
 805		if (error)
 806			return error;
 807		/*
 808		 * Now we need to clear the allocated blocks.
 809		 * Do this one block per transaction, to keep it simple.
 810		 */
 811		for (bno = map.br_startoff, fsbno = map.br_startblock;
 812		     bno < map.br_startoff + map.br_blockcount;
 813		     bno++, fsbno++) {
 814			/*
 815			 * Reserve log for one block zeroing.
 816			 */
 817			error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtzero,
 818					0, 0, 0, &tp);
 819			if (error)
 820				return error;
 821			/*
 822			 * Lock the bitmap inode.
 823			 */
 824			xfs_ilock(ip, XFS_ILOCK_EXCL);
 825			xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 826			/*
 827			 * Get a buffer for the block.
 828			 */
 829			d = XFS_FSB_TO_DADDR(mp, fsbno);
 830			bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
 831				mp->m_bsize, 0);
 832			if (bp == NULL) {
 833				error = -EIO;
 834				goto out_trans_cancel;
 835			}
 
 
 836			memset(bp->b_addr, 0, mp->m_sb.sb_blocksize);
 837			xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
 838			/*
 839			 * Commit the transaction.
 840			 */
 841			error = xfs_trans_commit(tp);
 842			if (error)
 843				return error;
 844		}
 845		/*
 846		 * Go on to the next extent, if any.
 847		 */
 848		oblocks = map.br_startoff + map.br_blockcount;
 849	}
 850
 851	return 0;
 852
 853out_trans_cancel:
 854	xfs_trans_cancel(tp);
 855	return error;
 856}
 857
 858static void
 859xfs_alloc_rsum_cache(
 860	xfs_mount_t	*mp,		/* file system mount structure */
 861	xfs_extlen_t	rbmblocks)	/* number of rt bitmap blocks */
 862{
 863	/*
 864	 * The rsum cache is initialized to all zeroes, which is trivially a
 865	 * lower bound on the minimum level with any free extents. We can
 866	 * continue without the cache if it couldn't be allocated.
 867	 */
 868	mp->m_rsum_cache = kmem_zalloc_large(rbmblocks, 0);
 869	if (!mp->m_rsum_cache)
 870		xfs_warn(mp, "could not allocate realtime summary cache");
 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	uint8_t		*rsum_cache;	/* old summary cache */
 902
 903	sbp = &mp->m_sb;
 904	/*
 905	 * Initial error checking.
 906	 */
 907	if (!capable(CAP_SYS_ADMIN))
 908		return -EPERM;
 909	if (mp->m_rtdev_targp == NULL || mp->m_rbmip == NULL ||
 910	    (nrblocks = in->newblocks) <= sbp->sb_rblocks ||
 911	    (sbp->sb_rblocks && (in->extsize != sbp->sb_rextsize)))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 912		return -EINVAL;
 913	if ((error = xfs_sb_validate_fsb_count(sbp, nrblocks)))
 
 
 
 
 
 
 
 
 914		return error;
 915	/*
 916	 * Read in the last block of the device, make sure it exists.
 917	 */
 918	error = xfs_buf_read_uncached(mp->m_rtdev_targp,
 919				XFS_FSB_TO_BB(mp, nrblocks - 1),
 920				XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
 921	if (error)
 922		return error;
 923	xfs_buf_relse(bp);
 924
 925	/*
 926	 * Calculate new parameters.  These are the final values to be reached.
 927	 */
 928	nrextents = nrblocks;
 929	do_div(nrextents, in->extsize);
 930	nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize);
 931	nrextslog = xfs_highbit32(nrextents);
 932	nrsumlevels = nrextslog + 1;
 933	nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
 934	nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
 935	nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
 936	/*
 937	 * New summary size can't be more than half the size of
 938	 * the log.  This prevents us from getting a log overflow,
 939	 * since we'll log basically the whole summary file at once.
 940	 */
 941	if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
 942		return -EINVAL;
 943	/*
 944	 * Get the old block counts for bitmap and summary inodes.
 945	 * These can't change since other growfs callers are locked out.
 946	 */
 947	rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_d.di_size);
 948	rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_d.di_size);
 949	/*
 950	 * Allocate space to the bitmap and summary files, as necessary.
 951	 */
 952	error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
 953	if (error)
 954		return error;
 955	error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
 956	if (error)
 957		return error;
 958
 959	rsum_cache = mp->m_rsum_cache;
 960	if (nrbmblocks != sbp->sb_rbmblocks)
 961		xfs_alloc_rsum_cache(mp, nrbmblocks);
 962
 963	/*
 964	 * Allocate a new (fake) mount/sb.
 965	 */
 966	nmp = kmem_alloc(sizeof(*nmp), 0);
 967	/*
 968	 * Loop over the bitmap blocks.
 969	 * We will do everything one bitmap block at a time.
 970	 * Skip the current block if it is exactly full.
 971	 * This also deals with the case where there were no rtextents before.
 972	 */
 973	for (bmbno = sbp->sb_rbmblocks -
 974		     ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
 975	     bmbno < nrbmblocks;
 976	     bmbno++) {
 977		xfs_trans_t	*tp;
 
 978
 979		*nmp = *mp;
 980		nsbp = &nmp->m_sb;
 981		/*
 982		 * Calculate new sb and mount fields for this round.
 983		 */
 984		nsbp->sb_rextsize = in->extsize;
 985		nsbp->sb_rbmblocks = bmbno + 1;
 986		nsbp->sb_rblocks =
 987			XFS_RTMIN(nrblocks,
 988				  nsbp->sb_rbmblocks * NBBY *
 989				  nsbp->sb_blocksize * nsbp->sb_rextsize);
 990		nsbp->sb_rextents = nsbp->sb_rblocks;
 991		do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
 992		ASSERT(nsbp->sb_rextents != 0);
 993		nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
 994		nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
 995		nrsumsize =
 996			(uint)sizeof(xfs_suminfo_t) * nrsumlevels *
 997			nsbp->sb_rbmblocks;
 998		nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
 999		nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
1000		/*
1001		 * Start a transaction, get the log reservation.
1002		 */
1003		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtfree, 0, 0, 0,
1004				&tp);
1005		if (error)
1006			break;
1007		/*
1008		 * Lock out other callers by grabbing the bitmap inode lock.
1009		 */
1010		xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
1011		xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
1012		/*
1013		 * Update the bitmap inode's size.
 
 
1014		 */
1015		mp->m_rbmip->i_d.di_size =
1016			nsbp->sb_rbmblocks * nsbp->sb_blocksize;
 
1017		xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1018		/*
1019		 * Get the summary inode into the transaction.
1020		 */
1021		xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL);
1022		xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
1023		/*
1024		 * Update the summary inode's size.
 
 
1025		 */
1026		mp->m_rsumip->i_d.di_size = nmp->m_rsumsize;
 
1027		xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
1028		/*
1029		 * Copy summary data from old to new sizes.
1030		 * Do this when the real size (not block-aligned) changes.
1031		 */
1032		if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
1033		    mp->m_rsumlevels != nmp->m_rsumlevels) {
1034			error = xfs_rtcopy_summary(mp, nmp, tp);
1035			if (error)
1036				goto error_cancel;
1037		}
1038		/*
1039		 * Update superblock fields.
1040		 */
1041		if (nsbp->sb_rextsize != sbp->sb_rextsize)
1042			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
1043				nsbp->sb_rextsize - sbp->sb_rextsize);
1044		if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
1045			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
1046				nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
1047		if (nsbp->sb_rblocks != sbp->sb_rblocks)
1048			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
1049				nsbp->sb_rblocks - sbp->sb_rblocks);
1050		if (nsbp->sb_rextents != sbp->sb_rextents)
1051			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
1052				nsbp->sb_rextents - sbp->sb_rextents);
1053		if (nsbp->sb_rextslog != sbp->sb_rextslog)
1054			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
1055				nsbp->sb_rextslog - sbp->sb_rextslog);
1056		/*
1057		 * Free new extent.
1058		 */
1059		bp = NULL;
1060		error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
1061			nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
1062		if (error) {
1063error_cancel:
1064			xfs_trans_cancel(tp);
1065			break;
1066		}
1067		/*
1068		 * Mark more blocks free in the superblock.
1069		 */
1070		xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
1071			nsbp->sb_rextents - sbp->sb_rextents);
1072		/*
1073		 * Update mp values into the real mp structure.
1074		 */
1075		mp->m_rsumlevels = nrsumlevels;
1076		mp->m_rsumsize = nrsumsize;
1077
1078		error = xfs_trans_commit(tp);
1079		if (error)
1080			break;
1081	}
 
 
 
 
 
1082
 
1083	/*
1084	 * Free the fake mp structure.
1085	 */
1086	kmem_free(nmp);
1087
1088	/*
1089	 * If we had to allocate a new rsum_cache, we either need to free the
1090	 * old one (if we succeeded) or free the new one and restore the old one
1091	 * (if there was an error).
1092	 */
1093	if (rsum_cache != mp->m_rsum_cache) {
1094		if (error) {
1095			kmem_free(mp->m_rsum_cache);
1096			mp->m_rsum_cache = rsum_cache;
1097		} else {
1098			kmem_free(rsum_cache);
1099		}
1100	}
1101
1102	return error;
1103}
1104
1105/*
1106 * Allocate an extent in the realtime subvolume, with the usual allocation
1107 * parameters.  The length units are all in realtime extents, as is the
1108 * result block number.
1109 */
1110int					/* error */
1111xfs_rtallocate_extent(
1112	xfs_trans_t	*tp,		/* transaction pointer */
1113	xfs_rtblock_t	bno,		/* starting block number to allocate */
1114	xfs_extlen_t	minlen,		/* minimum length to allocate */
1115	xfs_extlen_t	maxlen,		/* maximum length to allocate */
1116	xfs_extlen_t	*len,		/* out: actual length allocated */
1117	int		wasdel,		/* was a delayed allocation extent */
1118	xfs_extlen_t	prod,		/* extent product factor */
1119	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
1120{
1121	xfs_mount_t	*mp = tp->t_mountp;
1122	int		error;		/* error value */
1123	xfs_rtblock_t	r;		/* result allocated block */
1124	xfs_fsblock_t	sb;		/* summary file block number */
1125	xfs_buf_t	*sumbp;		/* summary file block buffer */
1126
1127	ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1128	ASSERT(minlen > 0 && minlen <= maxlen);
1129
1130	/*
1131	 * If prod is set then figure out what to do to minlen and maxlen.
1132	 */
1133	if (prod > 1) {
1134		xfs_extlen_t	i;
1135
1136		if ((i = maxlen % prod))
1137			maxlen -= i;
1138		if ((i = minlen % prod))
1139			minlen += prod - i;
1140		if (maxlen < minlen) {
1141			*rtblock = NULLRTBLOCK;
1142			return 0;
1143		}
1144	}
1145
1146retry:
1147	sumbp = NULL;
1148	if (bno == 0) {
1149		error = xfs_rtallocate_extent_size(mp, tp, minlen, maxlen, len,
1150				&sumbp,	&sb, prod, &r);
1151	} else {
1152		error = xfs_rtallocate_extent_near(mp, tp, bno, minlen, maxlen,
1153				len, &sumbp, &sb, prod, &r);
1154	}
1155
1156	if (error)
1157		return error;
1158
1159	/*
1160	 * If it worked, update the superblock.
1161	 */
1162	if (r != NULLRTBLOCK) {
1163		long	slen = (long)*len;
1164
1165		ASSERT(*len >= minlen && *len <= maxlen);
1166		if (wasdel)
1167			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
1168		else
1169			xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
1170	} else if (prod > 1) {
1171		prod = 1;
1172		goto retry;
1173	}
1174
1175	*rtblock = r;
1176	return 0;
1177}
1178
1179/*
1180 * Initialize realtime fields in the mount structure.
1181 */
1182int				/* error */
1183xfs_rtmount_init(
1184	struct xfs_mount	*mp)	/* file system mount structure */
1185{
1186	struct xfs_buf		*bp;	/* buffer for last block of subvolume */
1187	struct xfs_sb		*sbp;	/* filesystem superblock copy in mount */
1188	xfs_daddr_t		d;	/* address of last block of subvolume */
1189	int			error;
1190
1191	sbp = &mp->m_sb;
1192	if (sbp->sb_rblocks == 0)
1193		return 0;
1194	if (mp->m_rtdev_targp == NULL) {
1195		xfs_warn(mp,
1196	"Filesystem has a realtime volume, use rtdev=device option");
1197		return -ENODEV;
1198	}
1199	mp->m_rsumlevels = sbp->sb_rextslog + 1;
1200	mp->m_rsumsize =
1201		(uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
1202		sbp->sb_rbmblocks;
1203	mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
1204	mp->m_rbmip = mp->m_rsumip = NULL;
1205	/*
1206	 * Check that the realtime section is an ok size.
1207	 */
1208	d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
1209	if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
1210		xfs_warn(mp, "realtime mount -- %llu != %llu",
1211			(unsigned long long) XFS_BB_TO_FSB(mp, d),
1212			(unsigned long long) mp->m_sb.sb_rblocks);
1213		return -EFBIG;
1214	}
1215	error = xfs_buf_read_uncached(mp->m_rtdev_targp,
1216					d - XFS_FSB_TO_BB(mp, 1),
1217					XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
1218	if (error) {
1219		xfs_warn(mp, "realtime device size check failed");
1220		return error;
1221	}
1222	xfs_buf_relse(bp);
1223	return 0;
1224}
1225
1226/*
1227 * Get the bitmap and summary inodes and the summary cache into the mount
1228 * structure at mount time.
1229 */
1230int					/* error */
1231xfs_rtmount_inodes(
1232	xfs_mount_t	*mp)		/* file system mount structure */
1233{
1234	int		error;		/* error return value */
1235	xfs_sb_t	*sbp;
1236
1237	sbp = &mp->m_sb;
1238	error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip);
1239	if (error)
1240		return error;
1241	ASSERT(mp->m_rbmip != NULL);
1242
1243	error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip);
1244	if (error) {
1245		xfs_irele(mp->m_rbmip);
1246		return error;
1247	}
1248	ASSERT(mp->m_rsumip != NULL);
1249	xfs_alloc_rsum_cache(mp, sbp->sb_rbmblocks);
1250	return 0;
1251}
1252
1253void
1254xfs_rtunmount_inodes(
1255	struct xfs_mount	*mp)
1256{
1257	kmem_free(mp->m_rsum_cache);
1258	if (mp->m_rbmip)
1259		xfs_irele(mp->m_rbmip);
1260	if (mp->m_rsumip)
1261		xfs_irele(mp->m_rsumip);
1262}
1263
1264/*
1265 * Pick an extent for allocation at the start of a new realtime file.
1266 * Use the sequence number stored in the atime field of the bitmap inode.
1267 * Translate this to a fraction of the rtextents, and return the product
1268 * of rtextents and the fraction.
1269 * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
1270 */
1271int					/* error */
1272xfs_rtpick_extent(
1273	xfs_mount_t	*mp,		/* file system mount point */
1274	xfs_trans_t	*tp,		/* transaction pointer */
1275	xfs_extlen_t	len,		/* allocation length (rtextents) */
1276	xfs_rtblock_t	*pick)		/* result rt extent */
1277{
1278	xfs_rtblock_t	b;		/* result block */
1279	int		log2;		/* log of sequence number */
1280	uint64_t	resid;		/* residual after log removed */
1281	uint64_t	seq;		/* sequence number of file creation */
1282	uint64_t	*seqp;		/* pointer to seqno in inode */
1283
1284	ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1285
1286	seqp = (uint64_t *)&VFS_I(mp->m_rbmip)->i_atime;
1287	if (!(mp->m_rbmip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
1288		mp->m_rbmip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
1289		*seqp = 0;
1290	}
1291	seq = *seqp;
1292	if ((log2 = xfs_highbit64(seq)) == -1)
1293		b = 0;
1294	else {
1295		resid = seq - (1ULL << log2);
1296		b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
1297		    (log2 + 1);
1298		if (b >= mp->m_sb.sb_rextents)
1299			div64_u64_rem(b, mp->m_sb.sb_rextents, &b);
1300		if (b + len > mp->m_sb.sb_rextents)
1301			b = mp->m_sb.sb_rextents - len;
1302	}
1303	*seqp = seq + 1;
1304	xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1305	*pick = b;
1306	return 0;
1307}
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   4 * All Rights Reserved.
   5 */
   6#include "xfs.h"
   7#include "xfs_fs.h"
   8#include "xfs_shared.h"
   9#include "xfs_format.h"
  10#include "xfs_log_format.h"
  11#include "xfs_trans_resv.h"
  12#include "xfs_bit.h"
  13#include "xfs_mount.h"
  14#include "xfs_inode.h"
  15#include "xfs_bmap.h"
  16#include "xfs_bmap_btree.h"
  17#include "xfs_trans.h"
  18#include "xfs_trans_space.h"
  19#include "xfs_icache.h"
  20#include "xfs_rtalloc.h"
  21#include "xfs_sb.h"
  22
  23/*
  24 * Read and return the summary information for a given extent size,
  25 * bitmap block combination.
  26 * Keeps track of a current summary block, so we don't keep reading
  27 * it from the buffer cache.
  28 */
  29static int
  30xfs_rtget_summary(
  31	xfs_mount_t	*mp,		/* file system mount structure */
  32	xfs_trans_t	*tp,		/* transaction pointer */
  33	int		log,		/* log2 of extent size */
  34	xfs_rtblock_t	bbno,		/* bitmap block number */
  35	struct xfs_buf	**rbpp,		/* in/out: summary block buffer */
  36	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
  37	xfs_suminfo_t	*sum)		/* out: summary info for this block */
  38{
  39	return xfs_rtmodify_summary_int(mp, tp, log, bbno, 0, rbpp, rsb, sum);
  40}
  41
  42/*
  43 * Return whether there are any free extents in the size range given
  44 * by low and high, for the bitmap block bbno.
  45 */
  46STATIC int				/* error */
  47xfs_rtany_summary(
  48	xfs_mount_t	*mp,		/* file system mount structure */
  49	xfs_trans_t	*tp,		/* transaction pointer */
  50	int		low,		/* low log2 extent size */
  51	int		high,		/* high log2 extent size */
  52	xfs_rtblock_t	bbno,		/* bitmap block number */
  53	struct xfs_buf	**rbpp,		/* in/out: summary block buffer */
  54	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
  55	int		*stat)		/* out: any good extents here? */
  56{
  57	int		error;		/* error value */
  58	int		log;		/* loop counter, log2 of ext. size */
  59	xfs_suminfo_t	sum;		/* summary data */
  60
  61	/* There are no extents at levels < m_rsum_cache[bbno]. */
  62	if (mp->m_rsum_cache && low < mp->m_rsum_cache[bbno])
  63		low = mp->m_rsum_cache[bbno];
  64
  65	/*
  66	 * Loop over logs of extent sizes.
  67	 */
  68	for (log = low; log <= high; log++) {
  69		/*
  70		 * Get one summary datum.
  71		 */
  72		error = xfs_rtget_summary(mp, tp, log, bbno, rbpp, rsb, &sum);
  73		if (error) {
  74			return error;
  75		}
  76		/*
  77		 * If there are any, return success.
  78		 */
  79		if (sum) {
  80			*stat = 1;
  81			goto out;
  82		}
  83	}
  84	/*
  85	 * Found nothing, return failure.
  86	 */
  87	*stat = 0;
  88out:
  89	/* There were no extents at levels < log. */
  90	if (mp->m_rsum_cache && log > mp->m_rsum_cache[bbno])
  91		mp->m_rsum_cache[bbno] = log;
  92	return 0;
  93}
  94
  95
  96/*
  97 * Copy and transform the summary file, given the old and new
  98 * parameters in the mount structures.
  99 */
 100STATIC int				/* error */
 101xfs_rtcopy_summary(
 102	xfs_mount_t	*omp,		/* old file system mount point */
 103	xfs_mount_t	*nmp,		/* new file system mount point */
 104	xfs_trans_t	*tp)		/* transaction pointer */
 105{
 106	xfs_rtblock_t	bbno;		/* bitmap block number */
 107	struct xfs_buf	*bp;		/* summary buffer */
 108	int		error;		/* error return value */
 109	int		log;		/* summary level number (log length) */
 110	xfs_suminfo_t	sum;		/* summary data */
 111	xfs_fsblock_t	sumbno;		/* summary block number */
 112
 113	bp = NULL;
 114	for (log = omp->m_rsumlevels - 1; log >= 0; log--) {
 115		for (bbno = omp->m_sb.sb_rbmblocks - 1;
 116		     (xfs_srtblock_t)bbno >= 0;
 117		     bbno--) {
 118			error = xfs_rtget_summary(omp, tp, log, bbno, &bp,
 119				&sumbno, &sum);
 120			if (error)
 121				return error;
 122			if (sum == 0)
 123				continue;
 124			error = xfs_rtmodify_summary(omp, tp, log, bbno, -sum,
 125				&bp, &sumbno);
 126			if (error)
 127				return error;
 128			error = xfs_rtmodify_summary(nmp, tp, log, bbno, sum,
 129				&bp, &sumbno);
 130			if (error)
 131				return error;
 132			ASSERT(sum > 0);
 133		}
 134	}
 135	return 0;
 136}
 137/*
 138 * Mark an extent specified by start and len allocated.
 139 * Updates all the summary information as well as the bitmap.
 140 */
 141STATIC int				/* error */
 142xfs_rtallocate_range(
 143	xfs_mount_t	*mp,		/* file system mount point */
 144	xfs_trans_t	*tp,		/* transaction pointer */
 145	xfs_rtblock_t	start,		/* start block to allocate */
 146	xfs_extlen_t	len,		/* length to allocate */
 147	struct xfs_buf	**rbpp,		/* in/out: summary block buffer */
 148	xfs_fsblock_t	*rsb)		/* in/out: summary block number */
 149{
 150	xfs_rtblock_t	end;		/* end of the allocated extent */
 151	int		error;		/* error value */
 152	xfs_rtblock_t	postblock = 0;	/* first block allocated > end */
 153	xfs_rtblock_t	preblock = 0;	/* first block allocated < start */
 154
 155	end = start + len - 1;
 156	/*
 157	 * Assume we're allocating out of the middle of a free extent.
 158	 * We need to find the beginning and end of the extent so we can
 159	 * properly update the summary.
 160	 */
 161	error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
 162	if (error) {
 163		return error;
 164	}
 165	/*
 166	 * Find the next allocated block (end of free extent).
 167	 */
 168	error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
 169		&postblock);
 170	if (error) {
 171		return error;
 172	}
 173	/*
 174	 * Decrement the summary information corresponding to the entire
 175	 * (old) free extent.
 176	 */
 177	error = xfs_rtmodify_summary(mp, tp,
 178		XFS_RTBLOCKLOG(postblock + 1 - preblock),
 179		XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
 180	if (error) {
 181		return error;
 182	}
 183	/*
 184	 * If there are blocks not being allocated at the front of the
 185	 * old extent, add summary data for them to be free.
 186	 */
 187	if (preblock < start) {
 188		error = xfs_rtmodify_summary(mp, tp,
 189			XFS_RTBLOCKLOG(start - preblock),
 190			XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
 191		if (error) {
 192			return error;
 193		}
 194	}
 195	/*
 196	 * If there are blocks not being allocated at the end of the
 197	 * old extent, add summary data for them to be free.
 198	 */
 199	if (postblock > end) {
 200		error = xfs_rtmodify_summary(mp, tp,
 201			XFS_RTBLOCKLOG(postblock - end),
 202			XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
 203		if (error) {
 204			return error;
 205		}
 206	}
 207	/*
 208	 * Modify the bitmap to mark this extent allocated.
 209	 */
 210	error = xfs_rtmodify_range(mp, tp, start, len, 0);
 211	return error;
 212}
 213
 214/*
 215 * Attempt to allocate an extent minlen<=len<=maxlen starting from
 216 * bitmap block bbno.  If we don't get maxlen then use prod to trim
 217 * the length, if given.  Returns error; returns starting block in *rtblock.
 218 * The lengths are all in rtextents.
 219 */
 220STATIC int				/* error */
 221xfs_rtallocate_extent_block(
 222	xfs_mount_t	*mp,		/* file system mount point */
 223	xfs_trans_t	*tp,		/* transaction pointer */
 224	xfs_rtblock_t	bbno,		/* bitmap block number */
 225	xfs_extlen_t	minlen,		/* minimum length to allocate */
 226	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 227	xfs_extlen_t	*len,		/* out: actual length allocated */
 228	xfs_rtblock_t	*nextp,		/* out: next block to try */
 229	struct xfs_buf	**rbpp,		/* in/out: summary block buffer */
 230	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 231	xfs_extlen_t	prod,		/* extent product factor */
 232	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 233{
 234	xfs_rtblock_t	besti;		/* best rtblock found so far */
 235	xfs_rtblock_t	bestlen;	/* best length found so far */
 236	xfs_rtblock_t	end;		/* last rtblock in chunk */
 237	int		error;		/* error value */
 238	xfs_rtblock_t	i;		/* current rtblock trying */
 239	xfs_rtblock_t	next;		/* next rtblock to try */
 240	int		stat;		/* status from internal calls */
 241
 242	/*
 243	 * Loop over all the extents starting in this bitmap block,
 244	 * looking for one that's long enough.
 245	 */
 246	for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
 247		end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
 248	     i <= end;
 249	     i++) {
 250		/* Make sure we don't scan off the end of the rt volume. */
 251		maxlen = min(mp->m_sb.sb_rextents, i + maxlen) - i;
 252
 253		/*
 254		 * See if there's a free extent of maxlen starting at i.
 255		 * If it's not so then next will contain the first non-free.
 256		 */
 257		error = xfs_rtcheck_range(mp, tp, i, maxlen, 1, &next, &stat);
 258		if (error) {
 259			return error;
 260		}
 261		if (stat) {
 262			/*
 263			 * i for maxlen is all free, allocate and return that.
 264			 */
 265			error = xfs_rtallocate_range(mp, tp, i, maxlen, rbpp,
 266				rsb);
 267			if (error) {
 268				return error;
 269			}
 270			*len = maxlen;
 271			*rtblock = i;
 272			return 0;
 273		}
 274		/*
 275		 * In the case where we have a variable-sized allocation
 276		 * request, figure out how big this free piece is,
 277		 * and if it's big enough for the minimum, and the best
 278		 * so far, remember it.
 279		 */
 280		if (minlen < maxlen) {
 281			xfs_rtblock_t	thislen;	/* this extent size */
 282
 283			thislen = next - i;
 284			if (thislen >= minlen && thislen > bestlen) {
 285				besti = i;
 286				bestlen = thislen;
 287			}
 288		}
 289		/*
 290		 * If not done yet, find the start of the next free space.
 291		 */
 292		if (next < end) {
 293			error = xfs_rtfind_forw(mp, tp, next, end, &i);
 294			if (error) {
 295				return error;
 296			}
 297		} else
 298			break;
 299	}
 300	/*
 301	 * Searched the whole thing & didn't find a maxlen free extent.
 302	 */
 303	if (minlen < maxlen && besti != -1) {
 304		xfs_extlen_t	p;	/* amount to trim length by */
 305
 306		/*
 307		 * If size should be a multiple of prod, make that so.
 308		 */
 309		if (prod > 1) {
 310			div_u64_rem(bestlen, prod, &p);
 311			if (p)
 312				bestlen -= p;
 313		}
 314
 315		/*
 316		 * Allocate besti for bestlen & return that.
 317		 */
 318		error = xfs_rtallocate_range(mp, tp, besti, bestlen, rbpp, rsb);
 319		if (error) {
 320			return error;
 321		}
 322		*len = bestlen;
 323		*rtblock = besti;
 324		return 0;
 325	}
 326	/*
 327	 * Allocation failed.  Set *nextp to the next block to try.
 328	 */
 329	*nextp = next;
 330	*rtblock = NULLRTBLOCK;
 331	return 0;
 332}
 333
 334/*
 335 * Allocate an extent of length minlen<=len<=maxlen, starting at block
 336 * bno.  If we don't get maxlen then use prod to trim the length, if given.
 337 * Returns error; returns starting block in *rtblock.
 338 * The lengths are all in rtextents.
 339 */
 340STATIC int				/* error */
 341xfs_rtallocate_extent_exact(
 342	xfs_mount_t	*mp,		/* file system mount point */
 343	xfs_trans_t	*tp,		/* transaction pointer */
 344	xfs_rtblock_t	bno,		/* starting block number to allocate */
 345	xfs_extlen_t	minlen,		/* minimum length to allocate */
 346	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 347	xfs_extlen_t	*len,		/* out: actual length allocated */
 348	struct xfs_buf	**rbpp,		/* in/out: summary block buffer */
 349	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 350	xfs_extlen_t	prod,		/* extent product factor */
 351	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 352{
 353	int		error;		/* error value */
 354	xfs_extlen_t	i;		/* extent length trimmed due to prod */
 355	int		isfree;		/* extent is free */
 356	xfs_rtblock_t	next;		/* next block to try (dummy) */
 357
 358	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 359	/*
 360	 * Check if the range in question (for maxlen) is free.
 361	 */
 362	error = xfs_rtcheck_range(mp, tp, bno, maxlen, 1, &next, &isfree);
 363	if (error) {
 364		return error;
 365	}
 366	if (isfree) {
 367		/*
 368		 * If it is, allocate it and return success.
 369		 */
 370		error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
 371		if (error) {
 372			return error;
 373		}
 374		*len = maxlen;
 375		*rtblock = bno;
 376		return 0;
 377	}
 378	/*
 379	 * If not, allocate what there is, if it's at least minlen.
 380	 */
 381	maxlen = next - bno;
 382	if (maxlen < minlen) {
 383		/*
 384		 * Failed, return failure status.
 385		 */
 386		*rtblock = NULLRTBLOCK;
 387		return 0;
 388	}
 389	/*
 390	 * Trim off tail of extent, if prod is specified.
 391	 */
 392	if (prod > 1 && (i = maxlen % prod)) {
 393		maxlen -= i;
 394		if (maxlen < minlen) {
 395			/*
 396			 * Now we can't do it, return failure status.
 397			 */
 398			*rtblock = NULLRTBLOCK;
 399			return 0;
 400		}
 401	}
 402	/*
 403	 * Allocate what we can and return it.
 404	 */
 405	error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
 406	if (error) {
 407		return error;
 408	}
 409	*len = maxlen;
 410	*rtblock = bno;
 411	return 0;
 412}
 413
 414/*
 415 * Allocate an extent of length minlen<=len<=maxlen, starting as near
 416 * to bno as possible.  If we don't get maxlen then use prod to trim
 417 * the length, if given.  The lengths are all in rtextents.
 418 */
 419STATIC int				/* error */
 420xfs_rtallocate_extent_near(
 421	xfs_mount_t	*mp,		/* file system mount point */
 422	xfs_trans_t	*tp,		/* transaction pointer */
 423	xfs_rtblock_t	bno,		/* starting block number to allocate */
 424	xfs_extlen_t	minlen,		/* minimum length to allocate */
 425	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 426	xfs_extlen_t	*len,		/* out: actual length allocated */
 427	struct xfs_buf	**rbpp,		/* in/out: summary block buffer */
 428	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 429	xfs_extlen_t	prod,		/* extent product factor */
 430	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 431{
 432	int		any;		/* any useful extents from summary */
 433	xfs_rtblock_t	bbno;		/* bitmap block number */
 434	int		error;		/* error value */
 435	int		i;		/* bitmap block offset (loop control) */
 436	int		j;		/* secondary loop control */
 437	int		log2len;	/* log2 of minlen */
 438	xfs_rtblock_t	n;		/* next block to try */
 439	xfs_rtblock_t	r;		/* result block */
 440
 441	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 442	/*
 443	 * If the block number given is off the end, silently set it to
 444	 * the last block.
 445	 */
 446	if (bno >= mp->m_sb.sb_rextents)
 447		bno = mp->m_sb.sb_rextents - 1;
 448
 449	/* Make sure we don't run off the end of the rt volume. */
 450	maxlen = min(mp->m_sb.sb_rextents, bno + maxlen) - bno;
 451	if (maxlen < minlen) {
 452		*rtblock = NULLRTBLOCK;
 453		return 0;
 454	}
 455
 456	/*
 457	 * Try the exact allocation first.
 458	 */
 459	error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen, len,
 460		rbpp, rsb, prod, &r);
 461	if (error) {
 462		return error;
 463	}
 464	/*
 465	 * If the exact allocation worked, return that.
 466	 */
 467	if (r != NULLRTBLOCK) {
 468		*rtblock = r;
 469		return 0;
 470	}
 471	bbno = XFS_BITTOBLOCK(mp, bno);
 472	i = 0;
 473	ASSERT(minlen != 0);
 474	log2len = xfs_highbit32(minlen);
 475	/*
 476	 * Loop over all bitmap blocks (bbno + i is current block).
 477	 */
 478	for (;;) {
 479		/*
 480		 * Get summary information of extents of all useful levels
 481		 * starting in this bitmap block.
 482		 */
 483		error = xfs_rtany_summary(mp, tp, log2len, mp->m_rsumlevels - 1,
 484			bbno + i, rbpp, rsb, &any);
 485		if (error) {
 486			return error;
 487		}
 488		/*
 489		 * If there are any useful extents starting here, try
 490		 * allocating one.
 491		 */
 492		if (any) {
 493			/*
 494			 * On the positive side of the starting location.
 495			 */
 496			if (i >= 0) {
 497				/*
 498				 * Try to allocate an extent starting in
 499				 * this block.
 500				 */
 501				error = xfs_rtallocate_extent_block(mp, tp,
 502					bbno + i, minlen, maxlen, len, &n, rbpp,
 503					rsb, prod, &r);
 504				if (error) {
 505					return error;
 506				}
 507				/*
 508				 * If it worked, return it.
 509				 */
 510				if (r != NULLRTBLOCK) {
 511					*rtblock = r;
 512					return 0;
 513				}
 514			}
 515			/*
 516			 * On the negative side of the starting location.
 517			 */
 518			else {		/* i < 0 */
 519				/*
 520				 * Loop backwards through the bitmap blocks from
 521				 * the starting point-1 up to where we are now.
 522				 * There should be an extent which ends in this
 523				 * bitmap block and is long enough.
 524				 */
 525				for (j = -1; j > i; j--) {
 526					/*
 527					 * Grab the summary information for
 528					 * this bitmap block.
 529					 */
 530					error = xfs_rtany_summary(mp, tp,
 531						log2len, mp->m_rsumlevels - 1,
 532						bbno + j, rbpp, rsb, &any);
 533					if (error) {
 534						return error;
 535					}
 536					/*
 537					 * If there's no extent given in the
 538					 * summary that means the extent we
 539					 * found must carry over from an
 540					 * earlier block.  If there is an
 541					 * extent given, we've already tried
 542					 * that allocation, don't do it again.
 543					 */
 544					if (any)
 545						continue;
 546					error = xfs_rtallocate_extent_block(mp,
 547						tp, bbno + j, minlen, maxlen,
 548						len, &n, rbpp, rsb, prod, &r);
 549					if (error) {
 550						return error;
 551					}
 552					/*
 553					 * If it works, return the extent.
 554					 */
 555					if (r != NULLRTBLOCK) {
 556						*rtblock = r;
 557						return 0;
 558					}
 559				}
 560				/*
 561				 * There weren't intervening bitmap blocks
 562				 * with a long enough extent, or the
 563				 * allocation didn't work for some reason
 564				 * (i.e. it's a little * too short).
 565				 * Try to allocate from the summary block
 566				 * that we found.
 567				 */
 568				error = xfs_rtallocate_extent_block(mp, tp,
 569					bbno + i, minlen, maxlen, len, &n, rbpp,
 570					rsb, prod, &r);
 571				if (error) {
 572					return error;
 573				}
 574				/*
 575				 * If it works, return the extent.
 576				 */
 577				if (r != NULLRTBLOCK) {
 578					*rtblock = r;
 579					return 0;
 580				}
 581			}
 582		}
 583		/*
 584		 * Loop control.  If we were on the positive side, and there's
 585		 * still more blocks on the negative side, go there.
 586		 */
 587		if (i > 0 && (int)bbno - i >= 0)
 588			i = -i;
 589		/*
 590		 * If positive, and no more negative, but there are more
 591		 * positive, go there.
 592		 */
 593		else if (i > 0 && (int)bbno + i < mp->m_sb.sb_rbmblocks - 1)
 594			i++;
 595		/*
 596		 * If negative or 0 (just started), and there are positive
 597		 * blocks to go, go there.  The 0 case moves to block 1.
 598		 */
 599		else if (i <= 0 && (int)bbno - i < mp->m_sb.sb_rbmblocks - 1)
 600			i = 1 - i;
 601		/*
 602		 * If negative or 0 and there are more negative blocks,
 603		 * go there.
 604		 */
 605		else if (i <= 0 && (int)bbno + i > 0)
 606			i--;
 607		/*
 608		 * Must be done.  Return failure.
 609		 */
 610		else
 611			break;
 612	}
 613	*rtblock = NULLRTBLOCK;
 614	return 0;
 615}
 616
 617/*
 618 * Allocate an extent of length minlen<=len<=maxlen, with no position
 619 * specified.  If we don't get maxlen then use prod to trim
 620 * the length, if given.  The lengths are all in rtextents.
 621 */
 622STATIC int				/* error */
 623xfs_rtallocate_extent_size(
 624	xfs_mount_t	*mp,		/* file system mount point */
 625	xfs_trans_t	*tp,		/* transaction pointer */
 626	xfs_extlen_t	minlen,		/* minimum length to allocate */
 627	xfs_extlen_t	maxlen,		/* maximum length to allocate */
 628	xfs_extlen_t	*len,		/* out: actual length allocated */
 629	struct xfs_buf	**rbpp,		/* in/out: summary block buffer */
 630	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
 631	xfs_extlen_t	prod,		/* extent product factor */
 632	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
 633{
 634	int		error;		/* error value */
 635	int		i;		/* bitmap block number */
 636	int		l;		/* level number (loop control) */
 637	xfs_rtblock_t	n;		/* next block to be tried */
 638	xfs_rtblock_t	r;		/* result block number */
 639	xfs_suminfo_t	sum;		/* summary information for extents */
 640
 641	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
 642	ASSERT(maxlen != 0);
 643
 644	/*
 645	 * Loop over all the levels starting with maxlen.
 646	 * At each level, look at all the bitmap blocks, to see if there
 647	 * are extents starting there that are long enough (>= maxlen).
 648	 * Note, only on the initial level can the allocation fail if
 649	 * the summary says there's an extent.
 650	 */
 651	for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
 652		/*
 653		 * Loop over all the bitmap blocks.
 654		 */
 655		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
 656			/*
 657			 * Get the summary for this level/block.
 658			 */
 659			error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
 660				&sum);
 661			if (error) {
 662				return error;
 663			}
 664			/*
 665			 * Nothing there, on to the next block.
 666			 */
 667			if (!sum)
 668				continue;
 669			/*
 670			 * Try allocating the extent.
 671			 */
 672			error = xfs_rtallocate_extent_block(mp, tp, i, maxlen,
 673				maxlen, len, &n, rbpp, rsb, prod, &r);
 674			if (error) {
 675				return error;
 676			}
 677			/*
 678			 * If it worked, return that.
 679			 */
 680			if (r != NULLRTBLOCK) {
 681				*rtblock = r;
 682				return 0;
 683			}
 684			/*
 685			 * If the "next block to try" returned from the
 686			 * allocator is beyond the next bitmap block,
 687			 * skip to that bitmap block.
 688			 */
 689			if (XFS_BITTOBLOCK(mp, n) > i + 1)
 690				i = XFS_BITTOBLOCK(mp, n) - 1;
 691		}
 692	}
 693	/*
 694	 * Didn't find any maxlen blocks.  Try smaller ones, unless
 695	 * we're asking for a fixed size extent.
 696	 */
 697	if (minlen > --maxlen) {
 698		*rtblock = NULLRTBLOCK;
 699		return 0;
 700	}
 701	ASSERT(minlen != 0);
 702	ASSERT(maxlen != 0);
 703
 704	/*
 705	 * Loop over sizes, from maxlen down to minlen.
 706	 * This time, when we do the allocations, allow smaller ones
 707	 * to succeed.
 708	 */
 709	for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
 710		/*
 711		 * Loop over all the bitmap blocks, try an allocation
 712		 * starting in that block.
 713		 */
 714		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
 715			/*
 716			 * Get the summary information for this level/block.
 717			 */
 718			error =	xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
 719						  &sum);
 720			if (error) {
 721				return error;
 722			}
 723			/*
 724			 * If nothing there, go on to next.
 725			 */
 726			if (!sum)
 727				continue;
 728			/*
 729			 * Try the allocation.  Make sure the specified
 730			 * minlen/maxlen are in the possible range for
 731			 * this summary level.
 732			 */
 733			error = xfs_rtallocate_extent_block(mp, tp, i,
 734					XFS_RTMAX(minlen, 1 << l),
 735					XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
 736					len, &n, rbpp, rsb, prod, &r);
 737			if (error) {
 738				return error;
 739			}
 740			/*
 741			 * If it worked, return that extent.
 742			 */
 743			if (r != NULLRTBLOCK) {
 744				*rtblock = r;
 745				return 0;
 746			}
 747			/*
 748			 * If the "next block to try" returned from the
 749			 * allocator is beyond the next bitmap block,
 750			 * skip to that bitmap block.
 751			 */
 752			if (XFS_BITTOBLOCK(mp, n) > i + 1)
 753				i = XFS_BITTOBLOCK(mp, n) - 1;
 754		}
 755	}
 756	/*
 757	 * Got nothing, return failure.
 758	 */
 759	*rtblock = NULLRTBLOCK;
 760	return 0;
 761}
 762
 763/*
 764 * Allocate space to the bitmap or summary file, and zero it, for growfs.
 765 */
 766STATIC int
 767xfs_growfs_rt_alloc(
 768	struct xfs_mount	*mp,		/* file system mount point */
 769	xfs_extlen_t		oblocks,	/* old count of blocks */
 770	xfs_extlen_t		nblocks,	/* new count of blocks */
 771	struct xfs_inode	*ip)		/* inode (bitmap/summary) */
 772{
 773	xfs_fileoff_t		bno;		/* block number in file */
 774	struct xfs_buf		*bp;	/* temporary buffer for zeroing */
 775	xfs_daddr_t		d;		/* disk block address */
 776	int			error;		/* error return value */
 777	xfs_fsblock_t		fsbno;		/* filesystem block for bno */
 778	struct xfs_bmbt_irec	map;		/* block map output */
 779	int			nmap;		/* number of block maps */
 780	int			resblks;	/* space reservation */
 781	enum xfs_blft		buf_type;
 782	struct xfs_trans	*tp;
 783
 784	if (ip == mp->m_rsumip)
 785		buf_type = XFS_BLFT_RTSUMMARY_BUF;
 786	else
 787		buf_type = XFS_BLFT_RTBITMAP_BUF;
 788
 789	/*
 790	 * Allocate space to the file, as necessary.
 791	 */
 792	while (oblocks < nblocks) {
 793		resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
 794		/*
 795		 * Reserve space & log for one extent added to the file.
 796		 */
 797		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtalloc, resblks,
 798				0, 0, &tp);
 799		if (error)
 800			return error;
 801		/*
 802		 * Lock the inode.
 803		 */
 804		xfs_ilock(ip, XFS_ILOCK_EXCL);
 805		xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 806
 807		error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK,
 808				XFS_IEXT_ADD_NOSPLIT_CNT);
 809		if (error)
 810			goto out_trans_cancel;
 811
 812		/*
 813		 * Allocate blocks to the bitmap file.
 814		 */
 815		nmap = 1;
 816		error = xfs_bmapi_write(tp, ip, oblocks, nblocks - oblocks,
 817					XFS_BMAPI_METADATA, 0, &map, &nmap);
 
 818		if (!error && nmap < 1)
 819			error = -ENOSPC;
 820		if (error)
 821			goto out_trans_cancel;
 822		/*
 823		 * Free any blocks freed up in the transaction, then commit.
 824		 */
 825		error = xfs_trans_commit(tp);
 826		if (error)
 827			return error;
 828		/*
 829		 * Now we need to clear the allocated blocks.
 830		 * Do this one block per transaction, to keep it simple.
 831		 */
 832		for (bno = map.br_startoff, fsbno = map.br_startblock;
 833		     bno < map.br_startoff + map.br_blockcount;
 834		     bno++, fsbno++) {
 835			/*
 836			 * Reserve log for one block zeroing.
 837			 */
 838			error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtzero,
 839					0, 0, 0, &tp);
 840			if (error)
 841				return error;
 842			/*
 843			 * Lock the bitmap inode.
 844			 */
 845			xfs_ilock(ip, XFS_ILOCK_EXCL);
 846			xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 847			/*
 848			 * Get a buffer for the block.
 849			 */
 850			d = XFS_FSB_TO_DADDR(mp, fsbno);
 851			error = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
 852					mp->m_bsize, 0, &bp);
 853			if (error)
 
 854				goto out_trans_cancel;
 855
 856			xfs_trans_buf_set_type(tp, bp, buf_type);
 857			bp->b_ops = &xfs_rtbuf_ops;
 858			memset(bp->b_addr, 0, mp->m_sb.sb_blocksize);
 859			xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
 860			/*
 861			 * Commit the transaction.
 862			 */
 863			error = xfs_trans_commit(tp);
 864			if (error)
 865				return error;
 866		}
 867		/*
 868		 * Go on to the next extent, if any.
 869		 */
 870		oblocks = map.br_startoff + map.br_blockcount;
 871	}
 872
 873	return 0;
 874
 875out_trans_cancel:
 876	xfs_trans_cancel(tp);
 877	return error;
 878}
 879
 880static void
 881xfs_alloc_rsum_cache(
 882	xfs_mount_t	*mp,		/* file system mount structure */
 883	xfs_extlen_t	rbmblocks)	/* number of rt bitmap blocks */
 884{
 885	/*
 886	 * The rsum cache is initialized to all zeroes, which is trivially a
 887	 * lower bound on the minimum level with any free extents. We can
 888	 * continue without the cache if it couldn't be allocated.
 889	 */
 890	mp->m_rsum_cache = kvzalloc(rbmblocks, GFP_KERNEL);
 891	if (!mp->m_rsum_cache)
 892		xfs_warn(mp, "could not allocate realtime summary cache");
 893}
 894
 895/*
 896 * Visible (exported) functions.
 897 */
 898
 899/*
 900 * Grow the realtime area of the filesystem.
 901 */
 902int
 903xfs_growfs_rt(
 904	xfs_mount_t	*mp,		/* mount point for filesystem */
 905	xfs_growfs_rt_t	*in)		/* growfs rt input struct */
 906{
 907	xfs_rtblock_t	bmbno;		/* bitmap block number */
 908	struct xfs_buf	*bp;		/* temporary buffer */
 909	int		error;		/* error return value */
 910	xfs_mount_t	*nmp;		/* new (fake) mount structure */
 911	xfs_rfsblock_t	nrblocks;	/* new number of realtime blocks */
 912	xfs_extlen_t	nrbmblocks;	/* new number of rt bitmap blocks */
 913	xfs_rtblock_t	nrextents;	/* new number of realtime extents */
 914	uint8_t		nrextslog;	/* new log2 of sb_rextents */
 915	xfs_extlen_t	nrsumblocks;	/* new number of summary blocks */
 916	uint		nrsumlevels;	/* new rt summary levels */
 917	uint		nrsumsize;	/* new size of rt summary, bytes */
 918	xfs_sb_t	*nsbp;		/* new superblock */
 919	xfs_extlen_t	rbmblocks;	/* current number of rt bitmap blocks */
 920	xfs_extlen_t	rsumblocks;	/* current number of rt summary blks */
 921	xfs_sb_t	*sbp;		/* old superblock */
 922	xfs_fsblock_t	sumbno;		/* summary block number */
 923	uint8_t		*rsum_cache;	/* old summary cache */
 924
 925	sbp = &mp->m_sb;
 926
 
 
 927	if (!capable(CAP_SYS_ADMIN))
 928		return -EPERM;
 929
 930	/* Needs to have been mounted with an rt device. */
 931	if (!XFS_IS_REALTIME_MOUNT(mp))
 932		return -EINVAL;
 933	/*
 934	 * Mount should fail if the rt bitmap/summary files don't load, but
 935	 * we'll check anyway.
 936	 */
 937	if (!mp->m_rbmip || !mp->m_rsumip)
 938		return -EINVAL;
 939
 940	/* Shrink not supported. */
 941	if (in->newblocks <= sbp->sb_rblocks)
 942		return -EINVAL;
 943
 944	/* Can only change rt extent size when adding rt volume. */
 945	if (sbp->sb_rblocks > 0 && in->extsize != sbp->sb_rextsize)
 946		return -EINVAL;
 947
 948	/* Range check the extent size. */
 949	if (XFS_FSB_TO_B(mp, in->extsize) > XFS_MAX_RTEXTSIZE ||
 950	    XFS_FSB_TO_B(mp, in->extsize) < XFS_MIN_RTEXTSIZE)
 951		return -EINVAL;
 952
 953	/* Unsupported realtime features. */
 954	if (xfs_sb_version_hasrmapbt(&mp->m_sb) ||
 955	    xfs_sb_version_hasreflink(&mp->m_sb))
 956		return -EOPNOTSUPP;
 957
 958	nrblocks = in->newblocks;
 959	error = xfs_sb_validate_fsb_count(sbp, nrblocks);
 960	if (error)
 961		return error;
 962	/*
 963	 * Read in the last block of the device, make sure it exists.
 964	 */
 965	error = xfs_buf_read_uncached(mp->m_rtdev_targp,
 966				XFS_FSB_TO_BB(mp, nrblocks - 1),
 967				XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
 968	if (error)
 969		return error;
 970	xfs_buf_relse(bp);
 971
 972	/*
 973	 * Calculate new parameters.  These are the final values to be reached.
 974	 */
 975	nrextents = nrblocks;
 976	do_div(nrextents, in->extsize);
 977	nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize);
 978	nrextslog = xfs_highbit32(nrextents);
 979	nrsumlevels = nrextslog + 1;
 980	nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
 981	nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
 982	nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
 983	/*
 984	 * New summary size can't be more than half the size of
 985	 * the log.  This prevents us from getting a log overflow,
 986	 * since we'll log basically the whole summary file at once.
 987	 */
 988	if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
 989		return -EINVAL;
 990	/*
 991	 * Get the old block counts for bitmap and summary inodes.
 992	 * These can't change since other growfs callers are locked out.
 993	 */
 994	rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_disk_size);
 995	rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_disk_size);
 996	/*
 997	 * Allocate space to the bitmap and summary files, as necessary.
 998	 */
 999	error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
1000	if (error)
1001		return error;
1002	error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
1003	if (error)
1004		return error;
1005
1006	rsum_cache = mp->m_rsum_cache;
1007	if (nrbmblocks != sbp->sb_rbmblocks)
1008		xfs_alloc_rsum_cache(mp, nrbmblocks);
1009
1010	/*
1011	 * Allocate a new (fake) mount/sb.
1012	 */
1013	nmp = kmem_alloc(sizeof(*nmp), 0);
1014	/*
1015	 * Loop over the bitmap blocks.
1016	 * We will do everything one bitmap block at a time.
1017	 * Skip the current block if it is exactly full.
1018	 * This also deals with the case where there were no rtextents before.
1019	 */
1020	for (bmbno = sbp->sb_rbmblocks -
1021		     ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
1022	     bmbno < nrbmblocks;
1023	     bmbno++) {
1024		struct xfs_trans	*tp;
1025		xfs_rfsblock_t		nrblocks_step;
1026
1027		*nmp = *mp;
1028		nsbp = &nmp->m_sb;
1029		/*
1030		 * Calculate new sb and mount fields for this round.
1031		 */
1032		nsbp->sb_rextsize = in->extsize;
1033		nsbp->sb_rbmblocks = bmbno + 1;
1034		nrblocks_step = (bmbno + 1) * NBBY * nsbp->sb_blocksize *
1035				nsbp->sb_rextsize;
1036		nsbp->sb_rblocks = min(nrblocks, nrblocks_step);
 
1037		nsbp->sb_rextents = nsbp->sb_rblocks;
1038		do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
1039		ASSERT(nsbp->sb_rextents != 0);
1040		nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
1041		nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
1042		nrsumsize =
1043			(uint)sizeof(xfs_suminfo_t) * nrsumlevels *
1044			nsbp->sb_rbmblocks;
1045		nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
1046		nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
1047		/*
1048		 * Start a transaction, get the log reservation.
1049		 */
1050		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtfree, 0, 0, 0,
1051				&tp);
1052		if (error)
1053			break;
1054		/*
1055		 * Lock out other callers by grabbing the bitmap inode lock.
1056		 */
1057		xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP);
1058		xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
1059		/*
1060		 * Update the bitmap inode's size ondisk and incore.  We need
1061		 * to update the incore size so that inode inactivation won't
1062		 * punch what it thinks are "posteof" blocks.
1063		 */
1064		mp->m_rbmip->i_disk_size =
1065			nsbp->sb_rbmblocks * nsbp->sb_blocksize;
1066		i_size_write(VFS_I(mp->m_rbmip), mp->m_rbmip->i_disk_size);
1067		xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1068		/*
1069		 * Get the summary inode into the transaction.
1070		 */
1071		xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL | XFS_ILOCK_RTSUM);
1072		xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
1073		/*
1074		 * Update the summary inode's size.  We need to update the
1075		 * incore size so that inode inactivation won't punch what it
1076		 * thinks are "posteof" blocks.
1077		 */
1078		mp->m_rsumip->i_disk_size = nmp->m_rsumsize;
1079		i_size_write(VFS_I(mp->m_rsumip), mp->m_rsumip->i_disk_size);
1080		xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
1081		/*
1082		 * Copy summary data from old to new sizes.
1083		 * Do this when the real size (not block-aligned) changes.
1084		 */
1085		if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
1086		    mp->m_rsumlevels != nmp->m_rsumlevels) {
1087			error = xfs_rtcopy_summary(mp, nmp, tp);
1088			if (error)
1089				goto error_cancel;
1090		}
1091		/*
1092		 * Update superblock fields.
1093		 */
1094		if (nsbp->sb_rextsize != sbp->sb_rextsize)
1095			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
1096				nsbp->sb_rextsize - sbp->sb_rextsize);
1097		if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
1098			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
1099				nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
1100		if (nsbp->sb_rblocks != sbp->sb_rblocks)
1101			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
1102				nsbp->sb_rblocks - sbp->sb_rblocks);
1103		if (nsbp->sb_rextents != sbp->sb_rextents)
1104			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
1105				nsbp->sb_rextents - sbp->sb_rextents);
1106		if (nsbp->sb_rextslog != sbp->sb_rextslog)
1107			xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
1108				nsbp->sb_rextslog - sbp->sb_rextslog);
1109		/*
1110		 * Free new extent.
1111		 */
1112		bp = NULL;
1113		error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
1114			nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
1115		if (error) {
1116error_cancel:
1117			xfs_trans_cancel(tp);
1118			break;
1119		}
1120		/*
1121		 * Mark more blocks free in the superblock.
1122		 */
1123		xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
1124			nsbp->sb_rextents - sbp->sb_rextents);
1125		/*
1126		 * Update mp values into the real mp structure.
1127		 */
1128		mp->m_rsumlevels = nrsumlevels;
1129		mp->m_rsumsize = nrsumsize;
1130
1131		error = xfs_trans_commit(tp);
1132		if (error)
1133			break;
1134	}
1135	if (error)
1136		goto out_free;
1137
1138	/* Update secondary superblocks now the physical grow has completed */
1139	error = xfs_update_secondary_sbs(mp);
1140
1141out_free:
1142	/*
1143	 * Free the fake mp structure.
1144	 */
1145	kmem_free(nmp);
1146
1147	/*
1148	 * If we had to allocate a new rsum_cache, we either need to free the
1149	 * old one (if we succeeded) or free the new one and restore the old one
1150	 * (if there was an error).
1151	 */
1152	if (rsum_cache != mp->m_rsum_cache) {
1153		if (error) {
1154			kmem_free(mp->m_rsum_cache);
1155			mp->m_rsum_cache = rsum_cache;
1156		} else {
1157			kmem_free(rsum_cache);
1158		}
1159	}
1160
1161	return error;
1162}
1163
1164/*
1165 * Allocate an extent in the realtime subvolume, with the usual allocation
1166 * parameters.  The length units are all in realtime extents, as is the
1167 * result block number.
1168 */
1169int					/* error */
1170xfs_rtallocate_extent(
1171	xfs_trans_t	*tp,		/* transaction pointer */
1172	xfs_rtblock_t	bno,		/* starting block number to allocate */
1173	xfs_extlen_t	minlen,		/* minimum length to allocate */
1174	xfs_extlen_t	maxlen,		/* maximum length to allocate */
1175	xfs_extlen_t	*len,		/* out: actual length allocated */
1176	int		wasdel,		/* was a delayed allocation extent */
1177	xfs_extlen_t	prod,		/* extent product factor */
1178	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
1179{
1180	xfs_mount_t	*mp = tp->t_mountp;
1181	int		error;		/* error value */
1182	xfs_rtblock_t	r;		/* result allocated block */
1183	xfs_fsblock_t	sb;		/* summary file block number */
1184	struct xfs_buf	*sumbp;		/* summary file block buffer */
1185
1186	ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1187	ASSERT(minlen > 0 && minlen <= maxlen);
1188
1189	/*
1190	 * If prod is set then figure out what to do to minlen and maxlen.
1191	 */
1192	if (prod > 1) {
1193		xfs_extlen_t	i;
1194
1195		if ((i = maxlen % prod))
1196			maxlen -= i;
1197		if ((i = minlen % prod))
1198			minlen += prod - i;
1199		if (maxlen < minlen) {
1200			*rtblock = NULLRTBLOCK;
1201			return 0;
1202		}
1203	}
1204
1205retry:
1206	sumbp = NULL;
1207	if (bno == 0) {
1208		error = xfs_rtallocate_extent_size(mp, tp, minlen, maxlen, len,
1209				&sumbp,	&sb, prod, &r);
1210	} else {
1211		error = xfs_rtallocate_extent_near(mp, tp, bno, minlen, maxlen,
1212				len, &sumbp, &sb, prod, &r);
1213	}
1214
1215	if (error)
1216		return error;
1217
1218	/*
1219	 * If it worked, update the superblock.
1220	 */
1221	if (r != NULLRTBLOCK) {
1222		long	slen = (long)*len;
1223
1224		ASSERT(*len >= minlen && *len <= maxlen);
1225		if (wasdel)
1226			xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
1227		else
1228			xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
1229	} else if (prod > 1) {
1230		prod = 1;
1231		goto retry;
1232	}
1233
1234	*rtblock = r;
1235	return 0;
1236}
1237
1238/*
1239 * Initialize realtime fields in the mount structure.
1240 */
1241int				/* error */
1242xfs_rtmount_init(
1243	struct xfs_mount	*mp)	/* file system mount structure */
1244{
1245	struct xfs_buf		*bp;	/* buffer for last block of subvolume */
1246	struct xfs_sb		*sbp;	/* filesystem superblock copy in mount */
1247	xfs_daddr_t		d;	/* address of last block of subvolume */
1248	int			error;
1249
1250	sbp = &mp->m_sb;
1251	if (sbp->sb_rblocks == 0)
1252		return 0;
1253	if (mp->m_rtdev_targp == NULL) {
1254		xfs_warn(mp,
1255	"Filesystem has a realtime volume, use rtdev=device option");
1256		return -ENODEV;
1257	}
1258	mp->m_rsumlevels = sbp->sb_rextslog + 1;
1259	mp->m_rsumsize =
1260		(uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
1261		sbp->sb_rbmblocks;
1262	mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
1263	mp->m_rbmip = mp->m_rsumip = NULL;
1264	/*
1265	 * Check that the realtime section is an ok size.
1266	 */
1267	d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
1268	if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
1269		xfs_warn(mp, "realtime mount -- %llu != %llu",
1270			(unsigned long long) XFS_BB_TO_FSB(mp, d),
1271			(unsigned long long) mp->m_sb.sb_rblocks);
1272		return -EFBIG;
1273	}
1274	error = xfs_buf_read_uncached(mp->m_rtdev_targp,
1275					d - XFS_FSB_TO_BB(mp, 1),
1276					XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
1277	if (error) {
1278		xfs_warn(mp, "realtime device size check failed");
1279		return error;
1280	}
1281	xfs_buf_relse(bp);
1282	return 0;
1283}
1284
1285/*
1286 * Get the bitmap and summary inodes and the summary cache into the mount
1287 * structure at mount time.
1288 */
1289int					/* error */
1290xfs_rtmount_inodes(
1291	xfs_mount_t	*mp)		/* file system mount structure */
1292{
1293	int		error;		/* error return value */
1294	xfs_sb_t	*sbp;
1295
1296	sbp = &mp->m_sb;
1297	error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip);
1298	if (error)
1299		return error;
1300	ASSERT(mp->m_rbmip != NULL);
1301
1302	error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip);
1303	if (error) {
1304		xfs_irele(mp->m_rbmip);
1305		return error;
1306	}
1307	ASSERT(mp->m_rsumip != NULL);
1308	xfs_alloc_rsum_cache(mp, sbp->sb_rbmblocks);
1309	return 0;
1310}
1311
1312void
1313xfs_rtunmount_inodes(
1314	struct xfs_mount	*mp)
1315{
1316	kmem_free(mp->m_rsum_cache);
1317	if (mp->m_rbmip)
1318		xfs_irele(mp->m_rbmip);
1319	if (mp->m_rsumip)
1320		xfs_irele(mp->m_rsumip);
1321}
1322
1323/*
1324 * Pick an extent for allocation at the start of a new realtime file.
1325 * Use the sequence number stored in the atime field of the bitmap inode.
1326 * Translate this to a fraction of the rtextents, and return the product
1327 * of rtextents and the fraction.
1328 * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
1329 */
1330int					/* error */
1331xfs_rtpick_extent(
1332	xfs_mount_t	*mp,		/* file system mount point */
1333	xfs_trans_t	*tp,		/* transaction pointer */
1334	xfs_extlen_t	len,		/* allocation length (rtextents) */
1335	xfs_rtblock_t	*pick)		/* result rt extent */
1336{
1337	xfs_rtblock_t	b;		/* result block */
1338	int		log2;		/* log of sequence number */
1339	uint64_t	resid;		/* residual after log removed */
1340	uint64_t	seq;		/* sequence number of file creation */
1341	uint64_t	*seqp;		/* pointer to seqno in inode */
1342
1343	ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1344
1345	seqp = (uint64_t *)&VFS_I(mp->m_rbmip)->i_atime;
1346	if (!(mp->m_rbmip->i_diflags & XFS_DIFLAG_NEWRTBM)) {
1347		mp->m_rbmip->i_diflags |= XFS_DIFLAG_NEWRTBM;
1348		*seqp = 0;
1349	}
1350	seq = *seqp;
1351	if ((log2 = xfs_highbit64(seq)) == -1)
1352		b = 0;
1353	else {
1354		resid = seq - (1ULL << log2);
1355		b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
1356		    (log2 + 1);
1357		if (b >= mp->m_sb.sb_rextents)
1358			div64_u64_rem(b, mp->m_sb.sb_rextents, &b);
1359		if (b + len > mp->m_sb.sb_rextents)
1360			b = mp->m_sb.sb_rextents - len;
1361	}
1362	*seqp = seq + 1;
1363	xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1364	*pick = b;
1365	return 0;
1366}