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1// SPDX-License-Identifier: GPL-2.0+2/*3 * NILFS segment usage file.4 *5 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.6 *7 * Written by Koji Sato.8 * Revised by Ryusuke Konishi.9 */10 11#include <linux/kernel.h>12#include <linux/fs.h>13#include <linux/string.h>14#include <linux/buffer_head.h>15#include <linux/errno.h>16#include "mdt.h"17#include "sufile.h"18 19#include <trace/events/nilfs2.h>20 21/**22 * struct nilfs_sufile_info - on-memory private data of sufile23 * @mi: on-memory private data of metadata file24 * @ncleansegs: number of clean segments25 * @allocmin: lower limit of allocatable segment range26 * @allocmax: upper limit of allocatable segment range27 */28struct nilfs_sufile_info {29	struct nilfs_mdt_info mi;30	unsigned long ncleansegs;/* number of clean segments */31	__u64 allocmin;		/* lower limit of allocatable segment range */32	__u64 allocmax;		/* upper limit of allocatable segment range */33};34 35static inline struct nilfs_sufile_info *NILFS_SUI(struct inode *sufile)36{37	return (struct nilfs_sufile_info *)NILFS_MDT(sufile);38}39 40static inline unsigned long41nilfs_sufile_segment_usages_per_block(const struct inode *sufile)42{43	return NILFS_MDT(sufile)->mi_entries_per_block;44}45 46static unsigned long47nilfs_sufile_get_blkoff(const struct inode *sufile, __u64 segnum)48{49	__u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;50 51	t = div64_ul(t, nilfs_sufile_segment_usages_per_block(sufile));52	return (unsigned long)t;53}54 55static unsigned long56nilfs_sufile_get_offset(const struct inode *sufile, __u64 segnum)57{58	__u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;59 60	return do_div(t, nilfs_sufile_segment_usages_per_block(sufile));61}62 63static unsigned long64nilfs_sufile_segment_usages_in_block(const struct inode *sufile, __u64 curr,65				     __u64 max)66{67	return min_t(unsigned long,68		     nilfs_sufile_segment_usages_per_block(sufile) -69		     nilfs_sufile_get_offset(sufile, curr),70		     max - curr + 1);71}72 73static struct nilfs_segment_usage *74nilfs_sufile_block_get_segment_usage(const struct inode *sufile, __u64 segnum,75				     struct buffer_head *bh, void *kaddr)76{77	return kaddr + bh_offset(bh) +78		nilfs_sufile_get_offset(sufile, segnum) *79		NILFS_MDT(sufile)->mi_entry_size;80}81 82static int nilfs_sufile_get_header_block(struct inode *sufile,83					 struct buffer_head **bhp)84{85	int err = nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp);86 87	if (unlikely(err == -ENOENT)) {88		nilfs_error(sufile->i_sb,89			    "missing header block in segment usage metadata");90		err = -EIO;91	}92	return err;93}94 95static inline int96nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum,97				     int create, struct buffer_head **bhp)98{99	return nilfs_mdt_get_block(sufile,100				   nilfs_sufile_get_blkoff(sufile, segnum),101				   create, NULL, bhp);102}103 104static int nilfs_sufile_delete_segment_usage_block(struct inode *sufile,105						   __u64 segnum)106{107	return nilfs_mdt_delete_block(sufile,108				      nilfs_sufile_get_blkoff(sufile, segnum));109}110 111static void nilfs_sufile_mod_counter(struct buffer_head *header_bh,112				     u64 ncleanadd, u64 ndirtyadd)113{114	struct nilfs_sufile_header *header;115	void *kaddr;116 117	kaddr = kmap_local_page(header_bh->b_page);118	header = kaddr + bh_offset(header_bh);119	le64_add_cpu(&header->sh_ncleansegs, ncleanadd);120	le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd);121	kunmap_local(kaddr);122 123	mark_buffer_dirty(header_bh);124}125 126/**127 * nilfs_sufile_get_ncleansegs - return the number of clean segments128 * @sufile: inode of segment usage file129 */130unsigned long nilfs_sufile_get_ncleansegs(struct inode *sufile)131{132	return NILFS_SUI(sufile)->ncleansegs;133}134 135/**136 * nilfs_sufile_updatev - modify multiple segment usages at a time137 * @sufile: inode of segment usage file138 * @segnumv: array of segment numbers139 * @nsegs: size of @segnumv array140 * @create: creation flag141 * @ndone: place to store number of modified segments on @segnumv142 * @dofunc: primitive operation for the update143 *144 * Description: nilfs_sufile_updatev() repeatedly calls @dofunc145 * against the given array of segments.  The @dofunc is called with146 * buffers of a header block and the sufile block in which the target147 * segment usage entry is contained.  If @ndone is given, the number148 * of successfully modified segments from the head is stored in the149 * place @ndone points to.150 *151 * Return Value: On success, zero is returned.  On error, one of the152 * following negative error codes is returned.153 *154 * %-EIO - I/O error.155 *156 * %-ENOMEM - Insufficient amount of memory available.157 *158 * %-ENOENT - Given segment usage is in hole block (may be returned if159 *            @create is zero)160 *161 * %-EINVAL - Invalid segment usage number162 */163int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs,164			 int create, size_t *ndone,165			 void (*dofunc)(struct inode *, __u64,166					struct buffer_head *,167					struct buffer_head *))168{169	struct buffer_head *header_bh, *bh;170	unsigned long blkoff, prev_blkoff;171	__u64 *seg;172	size_t nerr = 0, n = 0;173	int ret = 0;174 175	if (unlikely(nsegs == 0))176		goto out;177 178	down_write(&NILFS_MDT(sufile)->mi_sem);179	for (seg = segnumv; seg < segnumv + nsegs; seg++) {180		if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) {181			nilfs_warn(sufile->i_sb,182				   "%s: invalid segment number: %llu",183				   __func__, (unsigned long long)*seg);184			nerr++;185		}186	}187	if (nerr > 0) {188		ret = -EINVAL;189		goto out_sem;190	}191 192	ret = nilfs_sufile_get_header_block(sufile, &header_bh);193	if (ret < 0)194		goto out_sem;195 196	seg = segnumv;197	blkoff = nilfs_sufile_get_blkoff(sufile, *seg);198	ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);199	if (ret < 0)200		goto out_header;201 202	for (;;) {203		dofunc(sufile, *seg, header_bh, bh);204 205		if (++seg >= segnumv + nsegs)206			break;207		prev_blkoff = blkoff;208		blkoff = nilfs_sufile_get_blkoff(sufile, *seg);209		if (blkoff == prev_blkoff)210			continue;211 212		/* get different block */213		brelse(bh);214		ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);215		if (unlikely(ret < 0))216			goto out_header;217	}218	brelse(bh);219 220 out_header:221	n = seg - segnumv;222	brelse(header_bh);223 out_sem:224	up_write(&NILFS_MDT(sufile)->mi_sem);225 out:226	if (ndone)227		*ndone = n;228	return ret;229}230 231int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create,232			void (*dofunc)(struct inode *, __u64,233				       struct buffer_head *,234				       struct buffer_head *))235{236	struct buffer_head *header_bh, *bh;237	int ret;238 239	if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {240		nilfs_warn(sufile->i_sb, "%s: invalid segment number: %llu",241			   __func__, (unsigned long long)segnum);242		return -EINVAL;243	}244	down_write(&NILFS_MDT(sufile)->mi_sem);245 246	ret = nilfs_sufile_get_header_block(sufile, &header_bh);247	if (ret < 0)248		goto out_sem;249 250	ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh);251	if (!ret) {252		dofunc(sufile, segnum, header_bh, bh);253		brelse(bh);254	}255	brelse(header_bh);256 257 out_sem:258	up_write(&NILFS_MDT(sufile)->mi_sem);259	return ret;260}261 262/**263 * nilfs_sufile_set_alloc_range - limit range of segment to be allocated264 * @sufile: inode of segment usage file265 * @start: minimum segment number of allocatable region (inclusive)266 * @end: maximum segment number of allocatable region (inclusive)267 *268 * Return Value: On success, 0 is returned.  On error, one of the269 * following negative error codes is returned.270 *271 * %-ERANGE - invalid segment region272 */273int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end)274{275	struct nilfs_sufile_info *sui = NILFS_SUI(sufile);276	__u64 nsegs;277	int ret = -ERANGE;278 279	down_write(&NILFS_MDT(sufile)->mi_sem);280	nsegs = nilfs_sufile_get_nsegments(sufile);281 282	if (start <= end && end < nsegs) {283		sui->allocmin = start;284		sui->allocmax = end;285		ret = 0;286	}287	up_write(&NILFS_MDT(sufile)->mi_sem);288	return ret;289}290 291/**292 * nilfs_sufile_alloc - allocate a segment293 * @sufile: inode of segment usage file294 * @segnump: pointer to segment number295 *296 * Description: nilfs_sufile_alloc() allocates a clean segment.297 *298 * Return Value: On success, 0 is returned and the segment number of the299 * allocated segment is stored in the place pointed by @segnump. On error, one300 * of the following negative error codes is returned.301 *302 * %-EIO - I/O error.303 *304 * %-ENOMEM - Insufficient amount of memory available.305 *306 * %-ENOSPC - No clean segment left.307 */308int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)309{310	struct buffer_head *header_bh, *su_bh;311	struct nilfs_sufile_header *header;312	struct nilfs_segment_usage *su;313	struct nilfs_sufile_info *sui = NILFS_SUI(sufile);314	size_t susz = NILFS_MDT(sufile)->mi_entry_size;315	__u64 segnum, maxsegnum, last_alloc;316	void *kaddr;317	unsigned long nsegments, nsus, cnt;318	int ret, j;319 320	down_write(&NILFS_MDT(sufile)->mi_sem);321 322	ret = nilfs_sufile_get_header_block(sufile, &header_bh);323	if (ret < 0)324		goto out_sem;325	kaddr = kmap_local_page(header_bh->b_page);326	header = kaddr + bh_offset(header_bh);327	last_alloc = le64_to_cpu(header->sh_last_alloc);328	kunmap_local(kaddr);329 330	nsegments = nilfs_sufile_get_nsegments(sufile);331	maxsegnum = sui->allocmax;332	segnum = last_alloc + 1;333	if (segnum < sui->allocmin || segnum > sui->allocmax)334		segnum = sui->allocmin;335 336	for (cnt = 0; cnt < nsegments; cnt += nsus) {337		if (segnum > maxsegnum) {338			if (cnt < sui->allocmax - sui->allocmin + 1) {339				/*340				 * wrap around in the limited region.341				 * if allocation started from342				 * sui->allocmin, this never happens.343				 */344				segnum = sui->allocmin;345				maxsegnum = last_alloc;346			} else if (segnum > sui->allocmin &&347				   sui->allocmax + 1 < nsegments) {348				segnum = sui->allocmax + 1;349				maxsegnum = nsegments - 1;350			} else if (sui->allocmin > 0)  {351				segnum = 0;352				maxsegnum = sui->allocmin - 1;353			} else {354				break; /* never happens */355			}356		}357		trace_nilfs2_segment_usage_check(sufile, segnum, cnt);358		ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,359							   &su_bh);360		if (ret < 0)361			goto out_header;362		kaddr = kmap_local_page(su_bh->b_page);363		su = nilfs_sufile_block_get_segment_usage(364			sufile, segnum, su_bh, kaddr);365 366		nsus = nilfs_sufile_segment_usages_in_block(367			sufile, segnum, maxsegnum);368		for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {369			if (!nilfs_segment_usage_clean(su))370				continue;371			/* found a clean segment */372			nilfs_segment_usage_set_dirty(su);373			kunmap_local(kaddr);374 375			kaddr = kmap_local_page(header_bh->b_page);376			header = kaddr + bh_offset(header_bh);377			le64_add_cpu(&header->sh_ncleansegs, -1);378			le64_add_cpu(&header->sh_ndirtysegs, 1);379			header->sh_last_alloc = cpu_to_le64(segnum);380			kunmap_local(kaddr);381 382			sui->ncleansegs--;383			mark_buffer_dirty(header_bh);384			mark_buffer_dirty(su_bh);385			nilfs_mdt_mark_dirty(sufile);386			brelse(su_bh);387			*segnump = segnum;388 389			trace_nilfs2_segment_usage_allocated(sufile, segnum);390 391			goto out_header;392		}393 394		kunmap_local(kaddr);395		brelse(su_bh);396	}397 398	/* no segments left */399	ret = -ENOSPC;400 401 out_header:402	brelse(header_bh);403 404 out_sem:405	up_write(&NILFS_MDT(sufile)->mi_sem);406	return ret;407}408 409void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum,410				 struct buffer_head *header_bh,411				 struct buffer_head *su_bh)412{413	struct nilfs_segment_usage *su;414	void *kaddr;415 416	kaddr = kmap_local_page(su_bh->b_page);417	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);418	if (unlikely(!nilfs_segment_usage_clean(su))) {419		nilfs_warn(sufile->i_sb, "%s: segment %llu must be clean",420			   __func__, (unsigned long long)segnum);421		kunmap_local(kaddr);422		return;423	}424	nilfs_segment_usage_set_dirty(su);425	kunmap_local(kaddr);426 427	nilfs_sufile_mod_counter(header_bh, -1, 1);428	NILFS_SUI(sufile)->ncleansegs--;429 430	mark_buffer_dirty(su_bh);431	nilfs_mdt_mark_dirty(sufile);432}433 434void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum,435			   struct buffer_head *header_bh,436			   struct buffer_head *su_bh)437{438	struct nilfs_segment_usage *su;439	void *kaddr;440	int clean, dirty;441 442	kaddr = kmap_local_page(su_bh->b_page);443	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);444	if (su->su_flags == cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY)) &&445	    su->su_nblocks == cpu_to_le32(0)) {446		kunmap_local(kaddr);447		return;448	}449	clean = nilfs_segment_usage_clean(su);450	dirty = nilfs_segment_usage_dirty(su);451 452	/* make the segment garbage */453	su->su_lastmod = cpu_to_le64(0);454	su->su_nblocks = cpu_to_le32(0);455	su->su_flags = cpu_to_le32(BIT(NILFS_SEGMENT_USAGE_DIRTY));456	kunmap_local(kaddr);457 458	nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1);459	NILFS_SUI(sufile)->ncleansegs -= clean;460 461	mark_buffer_dirty(su_bh);462	nilfs_mdt_mark_dirty(sufile);463}464 465void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum,466			  struct buffer_head *header_bh,467			  struct buffer_head *su_bh)468{469	struct nilfs_segment_usage *su;470	void *kaddr;471	int sudirty;472 473	kaddr = kmap_local_page(su_bh->b_page);474	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);475	if (nilfs_segment_usage_clean(su)) {476		nilfs_warn(sufile->i_sb, "%s: segment %llu is already clean",477			   __func__, (unsigned long long)segnum);478		kunmap_local(kaddr);479		return;480	}481	if (unlikely(nilfs_segment_usage_error(su)))482		nilfs_warn(sufile->i_sb, "free segment %llu marked in error",483			   (unsigned long long)segnum);484 485	sudirty = nilfs_segment_usage_dirty(su);486	if (unlikely(!sudirty))487		nilfs_warn(sufile->i_sb, "free unallocated segment %llu",488			   (unsigned long long)segnum);489 490	nilfs_segment_usage_set_clean(su);491	kunmap_local(kaddr);492	mark_buffer_dirty(su_bh);493 494	nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0);495	NILFS_SUI(sufile)->ncleansegs++;496 497	nilfs_mdt_mark_dirty(sufile);498 499	trace_nilfs2_segment_usage_freed(sufile, segnum);500}501 502/**503 * nilfs_sufile_mark_dirty - mark the buffer having a segment usage dirty504 * @sufile: inode of segment usage file505 * @segnum: segment number506 */507int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum)508{509	struct buffer_head *bh;510	void *kaddr;511	struct nilfs_segment_usage *su;512	int ret;513 514	down_write(&NILFS_MDT(sufile)->mi_sem);515	ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);516	if (unlikely(ret)) {517		if (ret == -ENOENT) {518			nilfs_error(sufile->i_sb,519				    "segment usage for segment %llu is unreadable due to a hole block",520				    (unsigned long long)segnum);521			ret = -EIO;522		}523		goto out_sem;524	}525 526	kaddr = kmap_local_page(bh->b_page);527	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);528	if (unlikely(nilfs_segment_usage_error(su))) {529		struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;530 531		kunmap_local(kaddr);532		brelse(bh);533		if (nilfs_segment_is_active(nilfs, segnum)) {534			nilfs_error(sufile->i_sb,535				    "active segment %llu is erroneous",536				    (unsigned long long)segnum);537		} else {538			/*539			 * Segments marked erroneous are never allocated by540			 * nilfs_sufile_alloc(); only active segments, ie,541			 * the segments indexed by ns_segnum or ns_nextnum,542			 * can be erroneous here.543			 */544			WARN_ON_ONCE(1);545		}546		ret = -EIO;547	} else {548		nilfs_segment_usage_set_dirty(su);549		kunmap_local(kaddr);550		mark_buffer_dirty(bh);551		nilfs_mdt_mark_dirty(sufile);552		brelse(bh);553	}554out_sem:555	up_write(&NILFS_MDT(sufile)->mi_sem);556	return ret;557}558 559/**560 * nilfs_sufile_set_segment_usage - set usage of a segment561 * @sufile: inode of segment usage file562 * @segnum: segment number563 * @nblocks: number of live blocks in the segment564 * @modtime: modification time (option)565 */566int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,567				   unsigned long nblocks, time64_t modtime)568{569	struct buffer_head *bh;570	struct nilfs_segment_usage *su;571	void *kaddr;572	int ret;573 574	down_write(&NILFS_MDT(sufile)->mi_sem);575	ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);576	if (ret < 0)577		goto out_sem;578 579	kaddr = kmap_local_page(bh->b_page);580	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);581	if (modtime) {582		/*583		 * Check segusage error and set su_lastmod only when updating584		 * this entry with a valid timestamp, not for cancellation.585		 */586		WARN_ON_ONCE(nilfs_segment_usage_error(su));587		su->su_lastmod = cpu_to_le64(modtime);588	}589	su->su_nblocks = cpu_to_le32(nblocks);590	kunmap_local(kaddr);591 592	mark_buffer_dirty(bh);593	nilfs_mdt_mark_dirty(sufile);594	brelse(bh);595 596 out_sem:597	up_write(&NILFS_MDT(sufile)->mi_sem);598	return ret;599}600 601/**602 * nilfs_sufile_get_stat - get segment usage statistics603 * @sufile: inode of segment usage file604 * @sustat: pointer to a structure of segment usage statistics605 *606 * Description: nilfs_sufile_get_stat() returns information about segment607 * usage.608 *609 * Return Value: On success, 0 is returned, and segment usage information is610 * stored in the place pointed by @sustat. On error, one of the following611 * negative error codes is returned.612 *613 * %-EIO - I/O error.614 *615 * %-ENOMEM - Insufficient amount of memory available.616 */617int nilfs_sufile_get_stat(struct inode *sufile, struct nilfs_sustat *sustat)618{619	struct buffer_head *header_bh;620	struct nilfs_sufile_header *header;621	struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;622	void *kaddr;623	int ret;624 625	down_read(&NILFS_MDT(sufile)->mi_sem);626 627	ret = nilfs_sufile_get_header_block(sufile, &header_bh);628	if (ret < 0)629		goto out_sem;630 631	kaddr = kmap_local_page(header_bh->b_page);632	header = kaddr + bh_offset(header_bh);633	sustat->ss_nsegs = nilfs_sufile_get_nsegments(sufile);634	sustat->ss_ncleansegs = le64_to_cpu(header->sh_ncleansegs);635	sustat->ss_ndirtysegs = le64_to_cpu(header->sh_ndirtysegs);636	sustat->ss_ctime = nilfs->ns_ctime;637	sustat->ss_nongc_ctime = nilfs->ns_nongc_ctime;638	spin_lock(&nilfs->ns_last_segment_lock);639	sustat->ss_prot_seq = nilfs->ns_prot_seq;640	spin_unlock(&nilfs->ns_last_segment_lock);641	kunmap_local(kaddr);642	brelse(header_bh);643 644 out_sem:645	up_read(&NILFS_MDT(sufile)->mi_sem);646	return ret;647}648 649void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,650			       struct buffer_head *header_bh,651			       struct buffer_head *su_bh)652{653	struct nilfs_segment_usage *su;654	void *kaddr;655	int suclean;656 657	kaddr = kmap_local_page(su_bh->b_page);658	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);659	if (nilfs_segment_usage_error(su)) {660		kunmap_local(kaddr);661		return;662	}663	suclean = nilfs_segment_usage_clean(su);664	nilfs_segment_usage_set_error(su);665	kunmap_local(kaddr);666 667	if (suclean) {668		nilfs_sufile_mod_counter(header_bh, -1, 0);669		NILFS_SUI(sufile)->ncleansegs--;670	}671	mark_buffer_dirty(su_bh);672	nilfs_mdt_mark_dirty(sufile);673}674 675/**676 * nilfs_sufile_truncate_range - truncate range of segment array677 * @sufile: inode of segment usage file678 * @start: start segment number (inclusive)679 * @end: end segment number (inclusive)680 *681 * Return Value: On success, 0 is returned.  On error, one of the682 * following negative error codes is returned.683 *684 * %-EIO - I/O error.685 *686 * %-ENOMEM - Insufficient amount of memory available.687 *688 * %-EINVAL - Invalid number of segments specified689 *690 * %-EBUSY - Dirty or active segments are present in the range691 */692static int nilfs_sufile_truncate_range(struct inode *sufile,693				       __u64 start, __u64 end)694{695	struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;696	struct buffer_head *header_bh;697	struct buffer_head *su_bh;698	struct nilfs_segment_usage *su, *su2;699	size_t susz = NILFS_MDT(sufile)->mi_entry_size;700	unsigned long segusages_per_block;701	unsigned long nsegs, ncleaned;702	__u64 segnum;703	void *kaddr;704	ssize_t n, nc;705	int ret;706	int j;707 708	nsegs = nilfs_sufile_get_nsegments(sufile);709 710	ret = -EINVAL;711	if (start > end || start >= nsegs)712		goto out;713 714	ret = nilfs_sufile_get_header_block(sufile, &header_bh);715	if (ret < 0)716		goto out;717 718	segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);719	ncleaned = 0;720 721	for (segnum = start; segnum <= end; segnum += n) {722		n = min_t(unsigned long,723			  segusages_per_block -724				  nilfs_sufile_get_offset(sufile, segnum),725			  end - segnum + 1);726		ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,727							   &su_bh);728		if (ret < 0) {729			if (ret != -ENOENT)730				goto out_header;731			/* hole */732			continue;733		}734		kaddr = kmap_local_page(su_bh->b_page);735		su = nilfs_sufile_block_get_segment_usage(736			sufile, segnum, su_bh, kaddr);737		su2 = su;738		for (j = 0; j < n; j++, su = (void *)su + susz) {739			if ((le32_to_cpu(su->su_flags) &740			     ~BIT(NILFS_SEGMENT_USAGE_ERROR)) ||741			    nilfs_segment_is_active(nilfs, segnum + j)) {742				ret = -EBUSY;743				kunmap_local(kaddr);744				brelse(su_bh);745				goto out_header;746			}747		}748		nc = 0;749		for (su = su2, j = 0; j < n; j++, su = (void *)su + susz) {750			if (nilfs_segment_usage_error(su)) {751				nilfs_segment_usage_set_clean(su);752				nc++;753			}754		}755		kunmap_local(kaddr);756		if (nc > 0) {757			mark_buffer_dirty(su_bh);758			ncleaned += nc;759		}760		brelse(su_bh);761 762		if (n == segusages_per_block) {763			/* make hole */764			nilfs_sufile_delete_segment_usage_block(sufile, segnum);765		}766	}767	ret = 0;768 769out_header:770	if (ncleaned > 0) {771		NILFS_SUI(sufile)->ncleansegs += ncleaned;772		nilfs_sufile_mod_counter(header_bh, ncleaned, 0);773		nilfs_mdt_mark_dirty(sufile);774	}775	brelse(header_bh);776out:777	return ret;778}779 780/**781 * nilfs_sufile_resize - resize segment array782 * @sufile: inode of segment usage file783 * @newnsegs: new number of segments784 *785 * Return Value: On success, 0 is returned.  On error, one of the786 * following negative error codes is returned.787 *788 * %-EIO - I/O error.789 *790 * %-ENOMEM - Insufficient amount of memory available.791 *792 * %-ENOSPC - Enough free space is not left for shrinking793 *794 * %-EBUSY - Dirty or active segments exist in the region to be truncated795 */796int nilfs_sufile_resize(struct inode *sufile, __u64 newnsegs)797{798	struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;799	struct buffer_head *header_bh;800	struct nilfs_sufile_header *header;801	struct nilfs_sufile_info *sui = NILFS_SUI(sufile);802	void *kaddr;803	unsigned long nsegs, nrsvsegs;804	int ret = 0;805 806	down_write(&NILFS_MDT(sufile)->mi_sem);807 808	nsegs = nilfs_sufile_get_nsegments(sufile);809	if (nsegs == newnsegs)810		goto out;811 812	ret = -ENOSPC;813	nrsvsegs = nilfs_nrsvsegs(nilfs, newnsegs);814	if (newnsegs < nsegs && nsegs - newnsegs + nrsvsegs > sui->ncleansegs)815		goto out;816 817	ret = nilfs_sufile_get_header_block(sufile, &header_bh);818	if (ret < 0)819		goto out;820 821	if (newnsegs > nsegs) {822		sui->ncleansegs += newnsegs - nsegs;823	} else /* newnsegs < nsegs */ {824		ret = nilfs_sufile_truncate_range(sufile, newnsegs, nsegs - 1);825		if (ret < 0)826			goto out_header;827 828		sui->ncleansegs -= nsegs - newnsegs;829 830		/*831		 * If the sufile is successfully truncated, immediately adjust832		 * the segment allocation space while locking the semaphore833		 * "mi_sem" so that nilfs_sufile_alloc() never allocates834		 * segments in the truncated space.835		 */836		sui->allocmax = newnsegs - 1;837		sui->allocmin = 0;838	}839 840	kaddr = kmap_local_page(header_bh->b_page);841	header = kaddr + bh_offset(header_bh);842	header->sh_ncleansegs = cpu_to_le64(sui->ncleansegs);843	kunmap_local(kaddr);844 845	mark_buffer_dirty(header_bh);846	nilfs_mdt_mark_dirty(sufile);847	nilfs_set_nsegments(nilfs, newnsegs);848 849out_header:850	brelse(header_bh);851out:852	up_write(&NILFS_MDT(sufile)->mi_sem);853	return ret;854}855 856/**857 * nilfs_sufile_get_suinfo - get segment usage information858 * @sufile: inode of segment usage file859 * @segnum: segment number to start looking860 * @buf:    array of suinfo861 * @sisz:   byte size of suinfo862 * @nsi:    size of suinfo array863 *864 * Return: Count of segment usage info items stored in the output buffer on865 * success, or the following negative error code on failure.866 * * %-EIO	- I/O error (including metadata corruption).867 * * %-ENOMEM	- Insufficient memory available.868 */869ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,870				unsigned int sisz, size_t nsi)871{872	struct buffer_head *su_bh;873	struct nilfs_segment_usage *su;874	struct nilfs_suinfo *si = buf;875	size_t susz = NILFS_MDT(sufile)->mi_entry_size;876	struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;877	void *kaddr;878	unsigned long nsegs, segusages_per_block;879	ssize_t n;880	int ret, i, j;881 882	down_read(&NILFS_MDT(sufile)->mi_sem);883 884	segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);885	nsegs = min_t(unsigned long,886		      nilfs_sufile_get_nsegments(sufile) - segnum,887		      nsi);888	for (i = 0; i < nsegs; i += n, segnum += n) {889		n = min_t(unsigned long,890			  segusages_per_block -891				  nilfs_sufile_get_offset(sufile, segnum),892			  nsegs - i);893		ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,894							   &su_bh);895		if (ret < 0) {896			if (ret != -ENOENT)897				goto out;898			/* hole */899			memset(si, 0, sisz * n);900			si = (void *)si + sisz * n;901			continue;902		}903 904		kaddr = kmap_local_page(su_bh->b_page);905		su = nilfs_sufile_block_get_segment_usage(906			sufile, segnum, su_bh, kaddr);907		for (j = 0; j < n;908		     j++, su = (void *)su + susz, si = (void *)si + sisz) {909			si->sui_lastmod = le64_to_cpu(su->su_lastmod);910			si->sui_nblocks = le32_to_cpu(su->su_nblocks);911			si->sui_flags = le32_to_cpu(su->su_flags) &912				~BIT(NILFS_SEGMENT_USAGE_ACTIVE);913			if (nilfs_segment_is_active(nilfs, segnum + j))914				si->sui_flags |=915					BIT(NILFS_SEGMENT_USAGE_ACTIVE);916		}917		kunmap_local(kaddr);918		brelse(su_bh);919	}920	ret = nsegs;921 922 out:923	up_read(&NILFS_MDT(sufile)->mi_sem);924	return ret;925}926 927/**928 * nilfs_sufile_set_suinfo - sets segment usage info929 * @sufile: inode of segment usage file930 * @buf: array of suinfo_update931 * @supsz: byte size of suinfo_update932 * @nsup: size of suinfo_update array933 *934 * Description: Takes an array of nilfs_suinfo_update structs and updates935 * segment usage accordingly. Only the fields indicated by the sup_flags936 * are updated.937 *938 * Return Value: On success, 0 is returned. On error, one of the939 * following negative error codes is returned.940 *941 * %-EIO - I/O error.942 *943 * %-ENOMEM - Insufficient amount of memory available.944 *945 * %-EINVAL - Invalid values in input (segment number, flags or nblocks)946 */947ssize_t nilfs_sufile_set_suinfo(struct inode *sufile, void *buf,948				unsigned int supsz, size_t nsup)949{950	struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;951	struct buffer_head *header_bh, *bh;952	struct nilfs_suinfo_update *sup, *supend = buf + supsz * nsup;953	struct nilfs_segment_usage *su;954	void *kaddr;955	unsigned long blkoff, prev_blkoff;956	int cleansi, cleansu, dirtysi, dirtysu;957	long ncleaned = 0, ndirtied = 0;958	int ret = 0;959 960	if (unlikely(nsup == 0))961		return ret;962 963	for (sup = buf; sup < supend; sup = (void *)sup + supsz) {964		if (sup->sup_segnum >= nilfs->ns_nsegments965			|| (sup->sup_flags &966				(~0UL << __NR_NILFS_SUINFO_UPDATE_FIELDS))967			|| (nilfs_suinfo_update_nblocks(sup) &&968				sup->sup_sui.sui_nblocks >969				nilfs->ns_blocks_per_segment))970			return -EINVAL;971	}972 973	down_write(&NILFS_MDT(sufile)->mi_sem);974 975	ret = nilfs_sufile_get_header_block(sufile, &header_bh);976	if (ret < 0)977		goto out_sem;978 979	sup = buf;980	blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);981	ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);982	if (ret < 0)983		goto out_header;984 985	for (;;) {986		kaddr = kmap_local_page(bh->b_page);987		su = nilfs_sufile_block_get_segment_usage(988			sufile, sup->sup_segnum, bh, kaddr);989 990		if (nilfs_suinfo_update_lastmod(sup))991			su->su_lastmod = cpu_to_le64(sup->sup_sui.sui_lastmod);992 993		if (nilfs_suinfo_update_nblocks(sup))994			su->su_nblocks = cpu_to_le32(sup->sup_sui.sui_nblocks);995 996		if (nilfs_suinfo_update_flags(sup)) {997			/*998			 * Active flag is a virtual flag projected by running999			 * nilfs kernel code - drop it not to write it to1000			 * disk.1001			 */1002			sup->sup_sui.sui_flags &=1003					~BIT(NILFS_SEGMENT_USAGE_ACTIVE);1004 1005			cleansi = nilfs_suinfo_clean(&sup->sup_sui);1006			cleansu = nilfs_segment_usage_clean(su);1007			dirtysi = nilfs_suinfo_dirty(&sup->sup_sui);1008			dirtysu = nilfs_segment_usage_dirty(su);1009 1010			if (cleansi && !cleansu)1011				++ncleaned;1012			else if (!cleansi && cleansu)1013				--ncleaned;1014 1015			if (dirtysi && !dirtysu)1016				++ndirtied;1017			else if (!dirtysi && dirtysu)1018				--ndirtied;1019 1020			su->su_flags = cpu_to_le32(sup->sup_sui.sui_flags);1021		}1022 1023		kunmap_local(kaddr);1024 1025		sup = (void *)sup + supsz;1026		if (sup >= supend)1027			break;1028 1029		prev_blkoff = blkoff;1030		blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);1031		if (blkoff == prev_blkoff)1032			continue;1033 1034		/* get different block */1035		mark_buffer_dirty(bh);1036		put_bh(bh);1037		ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);1038		if (unlikely(ret < 0))1039			goto out_mark;1040	}1041	mark_buffer_dirty(bh);1042	put_bh(bh);1043 1044 out_mark:1045	if (ncleaned || ndirtied) {1046		nilfs_sufile_mod_counter(header_bh, (u64)ncleaned,1047				(u64)ndirtied);1048		NILFS_SUI(sufile)->ncleansegs += ncleaned;1049	}1050	nilfs_mdt_mark_dirty(sufile);1051 out_header:1052	put_bh(header_bh);1053 out_sem:1054	up_write(&NILFS_MDT(sufile)->mi_sem);1055	return ret;1056}1057 1058/**1059 * nilfs_sufile_trim_fs() - trim ioctl handle function1060 * @sufile: inode of segment usage file1061 * @range: fstrim_range structure1062 *1063 * start:	First Byte to trim1064 * len:		number of Bytes to trim from start1065 * minlen:	minimum extent length in Bytes1066 *1067 * Decription: nilfs_sufile_trim_fs goes through all segments containing bytes1068 * from start to start+len. start is rounded up to the next block boundary1069 * and start+len is rounded down. For each clean segment blkdev_issue_discard1070 * function is invoked.1071 *1072 * Return Value: On success, 0 is returned or negative error code, otherwise.1073 */1074int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range)1075{1076	struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;1077	struct buffer_head *su_bh;1078	struct nilfs_segment_usage *su;1079	void *kaddr;1080	size_t n, i, susz = NILFS_MDT(sufile)->mi_entry_size;1081	sector_t seg_start, seg_end, start_block, end_block;1082	sector_t start = 0, nblocks = 0;1083	u64 segnum, segnum_end, minlen, len, max_blocks, ndiscarded = 0;1084	int ret = 0;1085	unsigned int sects_per_block;1086 1087	sects_per_block = (1 << nilfs->ns_blocksize_bits) /1088			bdev_logical_block_size(nilfs->ns_bdev);1089	len = range->len >> nilfs->ns_blocksize_bits;1090	minlen = range->minlen >> nilfs->ns_blocksize_bits;1091	max_blocks = ((u64)nilfs->ns_nsegments * nilfs->ns_blocks_per_segment);1092 1093	if (!len || range->start >= max_blocks << nilfs->ns_blocksize_bits)1094		return -EINVAL;1095 1096	start_block = (range->start + nilfs->ns_blocksize - 1) >>1097			nilfs->ns_blocksize_bits;1098 1099	/*1100	 * range->len can be very large (actually, it is set to1101	 * ULLONG_MAX by default) - truncate upper end of the range1102	 * carefully so as not to overflow.1103	 */1104	if (max_blocks - start_block < len)1105		end_block = max_blocks - 1;1106	else1107		end_block = start_block + len - 1;1108 1109	segnum = nilfs_get_segnum_of_block(nilfs, start_block);1110	segnum_end = nilfs_get_segnum_of_block(nilfs, end_block);1111 1112	down_read(&NILFS_MDT(sufile)->mi_sem);1113 1114	while (segnum <= segnum_end) {1115		n = nilfs_sufile_segment_usages_in_block(sufile, segnum,1116				segnum_end);1117 1118		ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,1119							   &su_bh);1120		if (ret < 0) {1121			if (ret != -ENOENT)1122				goto out_sem;1123			/* hole */1124			segnum += n;1125			continue;1126		}1127 1128		kaddr = kmap_local_page(su_bh->b_page);1129		su = nilfs_sufile_block_get_segment_usage(sufile, segnum,1130				su_bh, kaddr);1131		for (i = 0; i < n; ++i, ++segnum, su = (void *)su + susz) {1132			if (!nilfs_segment_usage_clean(su))1133				continue;1134 1135			nilfs_get_segment_range(nilfs, segnum, &seg_start,1136						&seg_end);1137 1138			if (!nblocks) {1139				/* start new extent */1140				start = seg_start;1141				nblocks = seg_end - seg_start + 1;1142				continue;1143			}1144 1145			if (start + nblocks == seg_start) {1146				/* add to previous extent */1147				nblocks += seg_end - seg_start + 1;1148				continue;1149			}1150 1151			/* discard previous extent */1152			if (start < start_block) {1153				nblocks -= start_block - start;1154				start = start_block;1155			}1156 1157			if (nblocks >= minlen) {1158				kunmap_local(kaddr);1159 1160				ret = blkdev_issue_discard(nilfs->ns_bdev,1161						start * sects_per_block,1162						nblocks * sects_per_block,1163						GFP_NOFS);1164				if (ret < 0) {1165					put_bh(su_bh);1166					goto out_sem;1167				}1168 1169				ndiscarded += nblocks;1170				kaddr = kmap_local_page(su_bh->b_page);1171				su = nilfs_sufile_block_get_segment_usage(1172					sufile, segnum, su_bh, kaddr);1173			}1174 1175			/* start new extent */1176			start = seg_start;1177			nblocks = seg_end - seg_start + 1;1178		}1179		kunmap_local(kaddr);1180		put_bh(su_bh);1181	}1182 1183 1184	if (nblocks) {1185		/* discard last extent */1186		if (start < start_block) {1187			nblocks -= start_block - start;1188			start = start_block;1189		}1190		if (start + nblocks > end_block + 1)1191			nblocks = end_block - start + 1;1192 1193		if (nblocks >= minlen) {1194			ret = blkdev_issue_discard(nilfs->ns_bdev,1195					start * sects_per_block,1196					nblocks * sects_per_block,1197					GFP_NOFS);1198			if (!ret)1199				ndiscarded += nblocks;1200		}1201	}1202 1203out_sem:1204	up_read(&NILFS_MDT(sufile)->mi_sem);1205 1206	range->len = ndiscarded << nilfs->ns_blocksize_bits;1207	return ret;1208}1209 1210/**1211 * nilfs_sufile_read - read or get sufile inode1212 * @sb: super block instance1213 * @susize: size of a segment usage entry1214 * @raw_inode: on-disk sufile inode1215 * @inodep: buffer to store the inode1216 */1217int nilfs_sufile_read(struct super_block *sb, size_t susize,1218		      struct nilfs_inode *raw_inode, struct inode **inodep)1219{1220	struct inode *sufile;1221	struct nilfs_sufile_info *sui;1222	struct buffer_head *header_bh;1223	struct nilfs_sufile_header *header;1224	void *kaddr;1225	int err;1226 1227	if (susize > sb->s_blocksize) {1228		nilfs_err(sb, "too large segment usage size: %zu bytes",1229			  susize);1230		return -EINVAL;1231	} else if (susize < NILFS_MIN_SEGMENT_USAGE_SIZE) {1232		nilfs_err(sb, "too small segment usage size: %zu bytes",1233			  susize);1234		return -EINVAL;1235	}1236 1237	sufile = nilfs_iget_locked(sb, NULL, NILFS_SUFILE_INO);1238	if (unlikely(!sufile))1239		return -ENOMEM;1240	if (!(sufile->i_state & I_NEW))1241		goto out;1242 1243	err = nilfs_mdt_init(sufile, NILFS_MDT_GFP, sizeof(*sui));1244	if (err)1245		goto failed;1246 1247	nilfs_mdt_set_entry_size(sufile, susize,1248				 sizeof(struct nilfs_sufile_header));1249 1250	err = nilfs_read_inode_common(sufile, raw_inode);1251	if (err)1252		goto failed;1253 1254	err = nilfs_mdt_get_block(sufile, 0, 0, NULL, &header_bh);1255	if (unlikely(err)) {1256		if (err == -ENOENT) {1257			nilfs_err(sb,1258				  "missing header block in segment usage metadata");1259			err = -EINVAL;1260		}1261		goto failed;1262	}1263 1264	sui = NILFS_SUI(sufile);1265	kaddr = kmap_local_page(header_bh->b_page);1266	header = kaddr + bh_offset(header_bh);1267	sui->ncleansegs = le64_to_cpu(header->sh_ncleansegs);1268	kunmap_local(kaddr);1269	brelse(header_bh);1270 1271	sui->allocmax = nilfs_sufile_get_nsegments(sufile) - 1;1272	sui->allocmin = 0;1273 1274	unlock_new_inode(sufile);1275 out:1276	*inodep = sufile;1277	return 0;1278 failed:1279	iget_failed(sufile);1280	return err;1281}1282