1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/ceph/ceph_debug.h>
   3
   4#include <linux/backing-dev.h>
   5#include <linux/fs.h>
   6#include <linux/mm.h>
   7#include <linux/swap.h>
   8#include <linux/pagemap.h>
 
   9#include <linux/slab.h>
  10#include <linux/pagevec.h>
  11#include <linux/task_io_accounting_ops.h>
  12#include <linux/signal.h>
  13#include <linux/iversion.h>
  14#include <linux/ktime.h>
  15#include <linux/netfs.h>
  16
  17#include "super.h"
  18#include "mds_client.h"
  19#include "cache.h"
  20#include "metric.h"
  21#include <linux/ceph/osd_client.h>
  22#include <linux/ceph/striper.h>
  23
  24/*
  25 * Ceph address space ops.
  26 *
  27 * There are a few funny things going on here.
  28 *
  29 * The page->private field is used to reference a struct
  30 * ceph_snap_context for _every_ dirty page.  This indicates which
  31 * snapshot the page was logically dirtied in, and thus which snap
  32 * context needs to be associated with the osd write during writeback.
  33 *
  34 * Similarly, struct ceph_inode_info maintains a set of counters to
  35 * count dirty pages on the inode.  In the absence of snapshots,
  36 * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count.
  37 *
  38 * When a snapshot is taken (that is, when the client receives
  39 * notification that a snapshot was taken), each inode with caps and
  40 * with dirty pages (dirty pages implies there is a cap) gets a new
  41 * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending
  42 * order, new snaps go to the tail).  The i_wrbuffer_ref_head count is
  43 * moved to capsnap->dirty. (Unless a sync write is currently in
  44 * progress.  In that case, the capsnap is said to be "pending", new
  45 * writes cannot start, and the capsnap isn't "finalized" until the
  46 * write completes (or fails) and a final size/mtime for the inode for
  47 * that snap can be settled upon.)  i_wrbuffer_ref_head is reset to 0.
  48 *
  49 * On writeback, we must submit writes to the osd IN SNAP ORDER.  So,
  50 * we look for the first capsnap in i_cap_snaps and write out pages in
  51 * that snap context _only_.  Then we move on to the next capsnap,
  52 * eventually reaching the "live" or "head" context (i.e., pages that
  53 * are not yet snapped) and are writing the most recently dirtied
  54 * pages.
  55 *
  56 * Invalidate and so forth must take care to ensure the dirty page
  57 * accounting is preserved.
  58 */
  59
  60#define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10))
  61#define CONGESTION_OFF_THRESH(congestion_kb)				\
  62	(CONGESTION_ON_THRESH(congestion_kb) -				\
  63	 (CONGESTION_ON_THRESH(congestion_kb) >> 2))
  64
  65static int ceph_netfs_check_write_begin(struct file *file, loff_t pos, unsigned int len,
  66					struct folio **foliop, void **_fsdata);
  67
  68static inline struct ceph_snap_context *page_snap_context(struct page *page)
  69{
  70	if (PagePrivate(page))
  71		return (void *)page->private;
  72	return NULL;
  73}
  74
  75/*
  76 * Dirty a page.  Optimistically adjust accounting, on the assumption
  77 * that we won't race with invalidate.  If we do, readjust.
  78 */
  79static bool ceph_dirty_folio(struct address_space *mapping, struct folio *folio)
  80{
 
  81	struct inode *inode;
  82	struct ceph_inode_info *ci;
  83	struct ceph_snap_context *snapc;
 
 
 
 
  84
  85	if (folio_test_dirty(folio)) {
  86		dout("%p dirty_folio %p idx %lu -- already dirty\n",
  87		     mapping->host, folio, folio->index);
  88		VM_BUG_ON_FOLIO(!folio_test_private(folio), folio);
  89		return false;
  90	}
  91
  92	inode = mapping->host;
  93	ci = ceph_inode(inode);
  94
  95	/* dirty the head */
  96	spin_lock(&ci->i_ceph_lock);
  97	BUG_ON(ci->i_wr_ref == 0); // caller should hold Fw reference
  98	if (__ceph_have_pending_cap_snap(ci)) {
  99		struct ceph_cap_snap *capsnap =
 100				list_last_entry(&ci->i_cap_snaps,
 101						struct ceph_cap_snap,
 102						ci_item);
 103		snapc = ceph_get_snap_context(capsnap->context);
 104		capsnap->dirty_pages++;
 105	} else {
 106		BUG_ON(!ci->i_head_snapc);
 107		snapc = ceph_get_snap_context(ci->i_head_snapc);
 108		++ci->i_wrbuffer_ref_head;
 109	}
 110	if (ci->i_wrbuffer_ref == 0)
 111		ihold(inode);
 112	++ci->i_wrbuffer_ref;
 113	dout("%p dirty_folio %p idx %lu head %d/%d -> %d/%d "
 114	     "snapc %p seq %lld (%d snaps)\n",
 115	     mapping->host, folio, folio->index,
 116	     ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref_head-1,
 117	     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
 118	     snapc, snapc->seq, snapc->num_snaps);
 119	spin_unlock(&ci->i_ceph_lock);
 120
 121	/*
 122	 * Reference snap context in folio->private.  Also set
 123	 * PagePrivate so that we get invalidate_folio callback.
 124	 */
 125	VM_WARN_ON_FOLIO(folio->private, folio);
 126	folio_attach_private(folio, snapc);
 
 
 
 
 
 127
 128	return ceph_fscache_dirty_folio(mapping, folio);
 129}
 130
 131/*
 132 * If we are truncating the full folio (i.e. offset == 0), adjust the
 133 * dirty folio counters appropriately.  Only called if there is private
 134 * data on the folio.
 135 */
 136static void ceph_invalidate_folio(struct folio *folio, size_t offset,
 137				size_t length)
 138{
 139	struct inode *inode;
 140	struct ceph_inode_info *ci;
 141	struct ceph_snap_context *snapc;
 142
 143	inode = folio->mapping->host;
 144	ci = ceph_inode(inode);
 145
 146	if (offset != 0 || length != folio_size(folio)) {
 147		dout("%p invalidate_folio idx %lu partial dirty page %zu~%zu\n",
 148		     inode, folio->index, offset, length);
 149		return;
 150	}
 151
 152	WARN_ON(!folio_test_locked(folio));
 153	if (folio_test_private(folio)) {
 154		dout("%p invalidate_folio idx %lu full dirty page\n",
 155		     inode, folio->index);
 156
 157		snapc = folio_detach_private(folio);
 158		ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
 159		ceph_put_snap_context(snapc);
 160	}
 161
 162	folio_wait_fscache(folio);
 163}
 164
 165static bool ceph_release_folio(struct folio *folio, gfp_t gfp)
 166{
 167	struct inode *inode = folio->mapping->host;
 168
 169	dout("%llx:%llx release_folio idx %lu (%sdirty)\n",
 170	     ceph_vinop(inode),
 171	     folio->index, folio_test_dirty(folio) ? "" : "not ");
 172
 173	if (folio_test_private(folio))
 174		return false;
 175
 176	if (folio_test_fscache(folio)) {
 177		if (current_is_kswapd() || !(gfp & __GFP_FS))
 178			return false;
 179		folio_wait_fscache(folio);
 180	}
 181	ceph_fscache_note_page_release(inode);
 182	return true;
 183}
 184
 185static void ceph_netfs_expand_readahead(struct netfs_io_request *rreq)
 186{
 187	struct inode *inode = rreq->inode;
 188	struct ceph_inode_info *ci = ceph_inode(inode);
 189	struct ceph_file_layout *lo = &ci->i_layout;
 190	u32 blockoff;
 191	u64 blockno;
 192
 193	/* Expand the start downward */
 194	blockno = div_u64_rem(rreq->start, lo->stripe_unit, &blockoff);
 195	rreq->start = blockno * lo->stripe_unit;
 196	rreq->len += blockoff;
 197
 198	/* Now, round up the length to the next block */
 199	rreq->len = roundup(rreq->len, lo->stripe_unit);
 200}
 201
 202static bool ceph_netfs_clamp_length(struct netfs_io_subrequest *subreq)
 
 
 
 203{
 204	struct inode *inode = subreq->rreq->inode;
 205	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 206	struct ceph_inode_info *ci = ceph_inode(inode);
 207	u64 objno, objoff;
 208	u32 xlen;
 209
 210	/* Truncate the extent at the end of the current block */
 211	ceph_calc_file_object_mapping(&ci->i_layout, subreq->start, subreq->len,
 212				      &objno, &objoff, &xlen);
 213	subreq->len = min(xlen, fsc->mount_options->rsize);
 214	return true;
 215}
 216
 217static void finish_netfs_read(struct ceph_osd_request *req)
 218{
 219	struct ceph_fs_client *fsc = ceph_inode_to_client(req->r_inode);
 220	struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
 221	struct netfs_io_subrequest *subreq = req->r_priv;
 222	int num_pages;
 223	int err = req->r_result;
 224
 225	ceph_update_read_metrics(&fsc->mdsc->metric, req->r_start_latency,
 226				 req->r_end_latency, osd_data->length, err);
 
 
 
 
 
 
 
 
 
 227
 228	dout("%s: result %d subreq->len=%zu i_size=%lld\n", __func__, req->r_result,
 229	     subreq->len, i_size_read(req->r_inode));
 
 230
 231	/* no object means success but no data */
 
 
 
 
 
 232	if (err == -ENOENT)
 233		err = 0;
 234	else if (err == -EBLOCKLISTED)
 235		fsc->blocklisted = true;
 236
 237	if (err >= 0 && err < subreq->len)
 238		__set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
 
 
 
 
 
 
 
 239
 240	netfs_subreq_terminated(subreq, err, false);
 
 241
 242	num_pages = calc_pages_for(osd_data->alignment, osd_data->length);
 243	ceph_put_page_vector(osd_data->pages, num_pages, false);
 244	iput(req->r_inode);
 245}
 246
 247static bool ceph_netfs_issue_op_inline(struct netfs_io_subrequest *subreq)
 248{
 249	struct netfs_io_request *rreq = subreq->rreq;
 250	struct inode *inode = rreq->inode;
 251	struct ceph_mds_reply_info_parsed *rinfo;
 252	struct ceph_mds_reply_info_in *iinfo;
 253	struct ceph_mds_request *req;
 254	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(inode->i_sb);
 255	struct ceph_inode_info *ci = ceph_inode(inode);
 256	struct iov_iter iter;
 257	ssize_t err = 0;
 258	size_t len;
 259	int mode;
 260
 261	__set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
 262	__clear_bit(NETFS_SREQ_COPY_TO_CACHE, &subreq->flags);
 263
 264	if (subreq->start >= inode->i_size)
 265		goto out;
 266
 267	/* We need to fetch the inline data. */
 268	mode = ceph_try_to_choose_auth_mds(inode, CEPH_STAT_CAP_INLINE_DATA);
 269	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, mode);
 270	if (IS_ERR(req)) {
 271		err = PTR_ERR(req);
 272		goto out;
 273	}
 274	req->r_ino1 = ci->i_vino;
 275	req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INLINE_DATA);
 276	req->r_num_caps = 2;
 
 277
 278	err = ceph_mdsc_do_request(mdsc, NULL, req);
 279	if (err < 0)
 280		goto out;
 281
 282	rinfo = &req->r_reply_info;
 283	iinfo = &rinfo->targeti;
 284	if (iinfo->inline_version == CEPH_INLINE_NONE) {
 285		/* The data got uninlined */
 286		ceph_mdsc_put_request(req);
 287		return false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 288	}
 289
 290	len = min_t(size_t, iinfo->inline_len - subreq->start, subreq->len);
 291	iov_iter_xarray(&iter, ITER_DEST, &rreq->mapping->i_pages, subreq->start, len);
 292	err = copy_to_iter(iinfo->inline_data + subreq->start, len, &iter);
 293	if (err == 0)
 294		err = -EFAULT;
 295
 296	ceph_mdsc_put_request(req);
 297out:
 298	netfs_subreq_terminated(subreq, err, false);
 299	return true;
 300}
 301
 302static void ceph_netfs_issue_read(struct netfs_io_subrequest *subreq)
 
 
 
 
 
 303{
 304	struct netfs_io_request *rreq = subreq->rreq;
 305	struct inode *inode = rreq->inode;
 306	struct ceph_inode_info *ci = ceph_inode(inode);
 307	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 308	struct ceph_osd_request *req = NULL;
 309	struct ceph_vino vino = ceph_vino(inode);
 310	struct iov_iter iter;
 
 
 311	struct page **pages;
 312	size_t page_off;
 313	int err = 0;
 314	u64 len = subreq->len;
 
 315
 316	if (ceph_inode_is_shutdown(inode)) {
 317		err = -EIO;
 318		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 319	}
 320
 321	if (ceph_has_inline_data(ci) && ceph_netfs_issue_op_inline(subreq))
 322		return;
 323
 324	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, vino, subreq->start, &len,
 325			0, 1, CEPH_OSD_OP_READ,
 326			CEPH_OSD_FLAG_READ | fsc->client->osdc.client->options->read_from_replica,
 327			NULL, ci->i_truncate_seq, ci->i_truncate_size, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 328	if (IS_ERR(req)) {
 329		err = PTR_ERR(req);
 330		req = NULL;
 331		goto out;
 332	}
 333
 334	dout("%s: pos=%llu orig_len=%zu len=%llu\n", __func__, subreq->start, subreq->len, len);
 335	iov_iter_xarray(&iter, ITER_DEST, &rreq->mapping->i_pages, subreq->start, len);
 336	err = iov_iter_get_pages_alloc2(&iter, &pages, len, &page_off);
 337	if (err < 0) {
 338		dout("%s: iov_ter_get_pages_alloc returned %d\n", __func__, err);
 339		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 340	}
 341
 342	/* should always give us a page-aligned read */
 343	WARN_ON_ONCE(page_off);
 344	len = err;
 345	err = 0;
 346
 347	osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false);
 348	req->r_callback = finish_netfs_read;
 349	req->r_priv = subreq;
 350	req->r_inode = inode;
 351	ihold(inode);
 352
 353	ceph_osdc_start_request(req->r_osdc, req);
 354out:
 
 
 355	ceph_osdc_put_request(req);
 356	if (err)
 357		netfs_subreq_terminated(subreq, err, false);
 358	dout("%s: result %d\n", __func__, err);
 359}
 360
 361static int ceph_init_request(struct netfs_io_request *rreq, struct file *file)
 362{
 363	struct inode *inode = rreq->inode;
 364	int got = 0, want = CEPH_CAP_FILE_CACHE;
 365	int ret = 0;
 366
 367	if (rreq->origin != NETFS_READAHEAD)
 368		return 0;
 369
 370	if (file) {
 371		struct ceph_rw_context *rw_ctx;
 372		struct ceph_file_info *fi = file->private_data;
 373
 374		rw_ctx = ceph_find_rw_context(fi);
 375		if (rw_ctx)
 376			return 0;
 377	}
 378
 379	/*
 380	 * readahead callers do not necessarily hold Fcb caps
 381	 * (e.g. fadvise, madvise).
 382	 */
 383	ret = ceph_try_get_caps(inode, CEPH_CAP_FILE_RD, want, true, &got);
 384	if (ret < 0) {
 385		dout("start_read %p, error getting cap\n", inode);
 386		return ret;
 387	}
 388
 389	if (!(got & want)) {
 390		dout("start_read %p, no cache cap\n", inode);
 391		return -EACCES;
 
 392	}
 393	if (ret == 0)
 394		return -EACCES;
 395
 396	rreq->netfs_priv = (void *)(uintptr_t)got;
 397	return 0;
 398}
 399
 400static void ceph_netfs_free_request(struct netfs_io_request *rreq)
 401{
 402	struct ceph_inode_info *ci = ceph_inode(rreq->inode);
 403	int got = (uintptr_t)rreq->netfs_priv;
 404
 405	if (got)
 406		ceph_put_cap_refs(ci, got);
 
 407}
 408
 409const struct netfs_request_ops ceph_netfs_ops = {
 410	.init_request		= ceph_init_request,
 411	.free_request		= ceph_netfs_free_request,
 412	.begin_cache_operation	= ceph_begin_cache_operation,
 413	.issue_read		= ceph_netfs_issue_read,
 414	.expand_readahead	= ceph_netfs_expand_readahead,
 415	.clamp_length		= ceph_netfs_clamp_length,
 416	.check_write_begin	= ceph_netfs_check_write_begin,
 417};
 418
 419#ifdef CONFIG_CEPH_FSCACHE
 420static void ceph_set_page_fscache(struct page *page)
 
 
 
 
 421{
 422	set_page_fscache(page);
 423}
 
 
 
 
 424
 425static void ceph_fscache_write_terminated(void *priv, ssize_t error, bool was_async)
 426{
 427	struct inode *inode = priv;
 428
 429	if (IS_ERR_VALUE(error) && error != -ENOBUFS)
 430		ceph_fscache_invalidate(inode, false);
 431}
 432
 433static void ceph_fscache_write_to_cache(struct inode *inode, u64 off, u64 len, bool caching)
 434{
 435	struct ceph_inode_info *ci = ceph_inode(inode);
 436	struct fscache_cookie *cookie = ceph_fscache_cookie(ci);
 437
 438	fscache_write_to_cache(cookie, inode->i_mapping, off, len, i_size_read(inode),
 439			       ceph_fscache_write_terminated, inode, caching);
 440}
 441#else
 442static inline void ceph_set_page_fscache(struct page *page)
 443{
 444}
 
 
 
 
 445
 446static inline void ceph_fscache_write_to_cache(struct inode *inode, u64 off, u64 len, bool caching)
 447{
 448}
 449#endif /* CONFIG_CEPH_FSCACHE */
 450
 451struct ceph_writeback_ctl
 452{
 453	loff_t i_size;
 454	u64 truncate_size;
 455	u32 truncate_seq;
 456	bool size_stable;
 457	bool head_snapc;
 458};
 459
 460/*
 461 * Get ref for the oldest snapc for an inode with dirty data... that is, the
 462 * only snap context we are allowed to write back.
 463 */
 464static struct ceph_snap_context *
 465get_oldest_context(struct inode *inode, struct ceph_writeback_ctl *ctl,
 466		   struct ceph_snap_context *page_snapc)
 467{
 468	struct ceph_inode_info *ci = ceph_inode(inode);
 469	struct ceph_snap_context *snapc = NULL;
 470	struct ceph_cap_snap *capsnap = NULL;
 471
 472	spin_lock(&ci->i_ceph_lock);
 473	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
 474		dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap,
 475		     capsnap->context, capsnap->dirty_pages);
 476		if (!capsnap->dirty_pages)
 477			continue;
 478
 479		/* get i_size, truncate_{seq,size} for page_snapc? */
 480		if (snapc && capsnap->context != page_snapc)
 481			continue;
 482
 483		if (ctl) {
 484			if (capsnap->writing) {
 485				ctl->i_size = i_size_read(inode);
 486				ctl->size_stable = false;
 487			} else {
 488				ctl->i_size = capsnap->size;
 489				ctl->size_stable = true;
 490			}
 491			ctl->truncate_size = capsnap->truncate_size;
 492			ctl->truncate_seq = capsnap->truncate_seq;
 493			ctl->head_snapc = false;
 494		}
 495
 496		if (snapc)
 497			break;
 498
 499		snapc = ceph_get_snap_context(capsnap->context);
 500		if (!page_snapc ||
 501		    page_snapc == snapc ||
 502		    page_snapc->seq > snapc->seq)
 503			break;
 504	}
 505	if (!snapc && ci->i_wrbuffer_ref_head) {
 506		snapc = ceph_get_snap_context(ci->i_head_snapc);
 507		dout(" head snapc %p has %d dirty pages\n",
 508		     snapc, ci->i_wrbuffer_ref_head);
 509		if (ctl) {
 510			ctl->i_size = i_size_read(inode);
 511			ctl->truncate_size = ci->i_truncate_size;
 512			ctl->truncate_seq = ci->i_truncate_seq;
 513			ctl->size_stable = false;
 514			ctl->head_snapc = true;
 515		}
 516	}
 517	spin_unlock(&ci->i_ceph_lock);
 518	return snapc;
 519}
 520
 521static u64 get_writepages_data_length(struct inode *inode,
 522				      struct page *page, u64 start)
 523{
 524	struct ceph_inode_info *ci = ceph_inode(inode);
 525	struct ceph_snap_context *snapc = page_snap_context(page);
 526	struct ceph_cap_snap *capsnap = NULL;
 527	u64 end = i_size_read(inode);
 528
 529	if (snapc != ci->i_head_snapc) {
 530		bool found = false;
 531		spin_lock(&ci->i_ceph_lock);
 532		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
 533			if (capsnap->context == snapc) {
 534				if (!capsnap->writing)
 535					end = capsnap->size;
 536				found = true;
 537				break;
 538			}
 539		}
 540		spin_unlock(&ci->i_ceph_lock);
 541		WARN_ON(!found);
 542	}
 543	if (end > page_offset(page) + thp_size(page))
 544		end = page_offset(page) + thp_size(page);
 545	return end > start ? end - start : 0;
 546}
 547
 548/*
 549 * Write a single page, but leave the page locked.
 550 *
 551 * If we get a write error, mark the mapping for error, but still adjust the
 552 * dirty page accounting (i.e., page is no longer dirty).
 553 */
 554static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 555{
 556	struct folio *folio = page_folio(page);
 557	struct inode *inode = page->mapping->host;
 558	struct ceph_inode_info *ci = ceph_inode(inode);
 559	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 560	struct ceph_snap_context *snapc, *oldest;
 561	loff_t page_off = page_offset(page);
 562	int err;
 563	loff_t len = thp_size(page);
 564	struct ceph_writeback_ctl ceph_wbc;
 565	struct ceph_osd_client *osdc = &fsc->client->osdc;
 566	struct ceph_osd_request *req;
 567	bool caching = ceph_is_cache_enabled(inode);
 568
 569	dout("writepage %p idx %lu\n", page, page->index);
 570
 571	if (ceph_inode_is_shutdown(inode))
 572		return -EIO;
 
 573
 574	/* verify this is a writeable snap context */
 575	snapc = page_snap_context(page);
 576	if (!snapc) {
 577		dout("writepage %p page %p not dirty?\n", inode, page);
 578		return 0;
 579	}
 580	oldest = get_oldest_context(inode, &ceph_wbc, snapc);
 581	if (snapc->seq > oldest->seq) {
 582		dout("writepage %p page %p snapc %p not writeable - noop\n",
 583		     inode, page, snapc);
 584		/* we should only noop if called by kswapd */
 585		WARN_ON(!(current->flags & PF_MEMALLOC));
 586		ceph_put_snap_context(oldest);
 587		redirty_page_for_writepage(wbc, page);
 588		return 0;
 589	}
 590	ceph_put_snap_context(oldest);
 591
 592	/* is this a partial page at end of file? */
 593	if (page_off >= ceph_wbc.i_size) {
 594		dout("folio at %lu beyond eof %llu\n", folio->index,
 595				ceph_wbc.i_size);
 596		folio_invalidate(folio, 0, folio_size(folio));
 597		return 0;
 598	}
 599
 600	if (ceph_wbc.i_size < page_off + len)
 601		len = ceph_wbc.i_size - page_off;
 602
 603	dout("writepage %p page %p index %lu on %llu~%llu snapc %p seq %lld\n",
 604	     inode, page, page->index, page_off, len, snapc, snapc->seq);
 605
 606	if (atomic_long_inc_return(&fsc->writeback_count) >
 607	    CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
 608		fsc->write_congested = true;
 609
 610	req = ceph_osdc_new_request(osdc, &ci->i_layout, ceph_vino(inode), page_off, &len, 0, 1,
 611				    CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE, snapc,
 612				    ceph_wbc.truncate_seq, ceph_wbc.truncate_size,
 613				    true);
 614	if (IS_ERR(req)) {
 615		redirty_page_for_writepage(wbc, page);
 616		return PTR_ERR(req);
 617	}
 618
 619	set_page_writeback(page);
 620	if (caching)
 621		ceph_set_page_fscache(page);
 622	ceph_fscache_write_to_cache(inode, page_off, len, caching);
 623
 624	/* it may be a short write due to an object boundary */
 625	WARN_ON_ONCE(len > thp_size(page));
 626	osd_req_op_extent_osd_data_pages(req, 0, &page, len, 0, false, false);
 627	dout("writepage %llu~%llu (%llu bytes)\n", page_off, len, len);
 628
 629	req->r_mtime = inode->i_mtime;
 630	ceph_osdc_start_request(osdc, req);
 631	err = ceph_osdc_wait_request(osdc, req);
 632
 633	ceph_update_write_metrics(&fsc->mdsc->metric, req->r_start_latency,
 634				  req->r_end_latency, len, err);
 635
 636	ceph_osdc_put_request(req);
 637	if (err == 0)
 638		err = len;
 639
 640	if (err < 0) {
 641		struct writeback_control tmp_wbc;
 642		if (!wbc)
 643			wbc = &tmp_wbc;
 644		if (err == -ERESTARTSYS) {
 645			/* killed by SIGKILL */
 646			dout("writepage interrupted page %p\n", page);
 647			redirty_page_for_writepage(wbc, page);
 648			end_page_writeback(page);
 649			return err;
 650		}
 651		if (err == -EBLOCKLISTED)
 652			fsc->blocklisted = true;
 653		dout("writepage setting page/mapping error %d %p\n",
 654		     err, page);
 655		mapping_set_error(&inode->i_data, err);
 656		wbc->pages_skipped++;
 657	} else {
 658		dout("writepage cleaned page %p\n", page);
 659		err = 0;  /* vfs expects us to return 0 */
 660	}
 661	oldest = detach_page_private(page);
 662	WARN_ON_ONCE(oldest != snapc);
 663	end_page_writeback(page);
 664	ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
 665	ceph_put_snap_context(snapc);  /* page's reference */
 666
 667	if (atomic_long_dec_return(&fsc->writeback_count) <
 668	    CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
 669		fsc->write_congested = false;
 670
 671	return err;
 672}
 673
 674static int ceph_writepage(struct page *page, struct writeback_control *wbc)
 675{
 676	int err;
 677	struct inode *inode = page->mapping->host;
 678	BUG_ON(!inode);
 679	ihold(inode);
 680
 681	if (wbc->sync_mode == WB_SYNC_NONE &&
 682	    ceph_inode_to_client(inode)->write_congested)
 683		return AOP_WRITEPAGE_ACTIVATE;
 684
 685	wait_on_page_fscache(page);
 686
 687	err = writepage_nounlock(page, wbc);
 688	if (err == -ERESTARTSYS) {
 689		/* direct memory reclaimer was killed by SIGKILL. return 0
 690		 * to prevent caller from setting mapping/page error */
 691		err = 0;
 692	}
 693	unlock_page(page);
 694	iput(inode);
 695	return err;
 696}
 697
 698/*
 699 * async writeback completion handler.
 700 *
 701 * If we get an error, set the mapping error bit, but not the individual
 702 * page error bits.
 703 */
 704static void writepages_finish(struct ceph_osd_request *req)
 705{
 706	struct inode *inode = req->r_inode;
 707	struct ceph_inode_info *ci = ceph_inode(inode);
 708	struct ceph_osd_data *osd_data;
 709	struct page *page;
 710	int num_pages, total_pages = 0;
 711	int i, j;
 712	int rc = req->r_result;
 713	struct ceph_snap_context *snapc = req->r_snapc;
 714	struct address_space *mapping = inode->i_mapping;
 715	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 716	unsigned int len = 0;
 717	bool remove_page;
 718
 719	dout("writepages_finish %p rc %d\n", inode, rc);
 720	if (rc < 0) {
 721		mapping_set_error(mapping, rc);
 722		ceph_set_error_write(ci);
 723		if (rc == -EBLOCKLISTED)
 724			fsc->blocklisted = true;
 725	} else {
 726		ceph_clear_error_write(ci);
 727	}
 728
 729	/*
 730	 * We lost the cache cap, need to truncate the page before
 731	 * it is unlocked, otherwise we'd truncate it later in the
 732	 * page truncation thread, possibly losing some data that
 733	 * raced its way in
 734	 */
 735	remove_page = !(ceph_caps_issued(ci) &
 736			(CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO));
 737
 738	/* clean all pages */
 739	for (i = 0; i < req->r_num_ops; i++) {
 740		if (req->r_ops[i].op != CEPH_OSD_OP_WRITE) {
 741			pr_warn("%s incorrect op %d req %p index %d tid %llu\n",
 742				__func__, req->r_ops[i].op, req, i, req->r_tid);
 743			break;
 744		}
 745
 746		osd_data = osd_req_op_extent_osd_data(req, i);
 747		BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
 748		len += osd_data->length;
 749		num_pages = calc_pages_for((u64)osd_data->alignment,
 750					   (u64)osd_data->length);
 751		total_pages += num_pages;
 752		for (j = 0; j < num_pages; j++) {
 753			page = osd_data->pages[j];
 754			BUG_ON(!page);
 755			WARN_ON(!PageUptodate(page));
 756
 757			if (atomic_long_dec_return(&fsc->writeback_count) <
 758			     CONGESTION_OFF_THRESH(
 759					fsc->mount_options->congestion_kb))
 760				fsc->write_congested = false;
 
 761
 762			ceph_put_snap_context(detach_page_private(page));
 763			end_page_writeback(page);
 
 764			dout("unlocking %p\n", page);
 
 765
 766			if (remove_page)
 767				generic_error_remove_page(inode->i_mapping,
 768							  page);
 769
 770			unlock_page(page);
 771		}
 772		dout("writepages_finish %p wrote %llu bytes cleaned %d pages\n",
 773		     inode, osd_data->length, rc >= 0 ? num_pages : 0);
 774
 775		release_pages(osd_data->pages, num_pages);
 776	}
 777
 778	ceph_update_write_metrics(&fsc->mdsc->metric, req->r_start_latency,
 779				  req->r_end_latency, len, rc);
 780
 781	ceph_put_wrbuffer_cap_refs(ci, total_pages, snapc);
 782
 783	osd_data = osd_req_op_extent_osd_data(req, 0);
 784	if (osd_data->pages_from_pool)
 785		mempool_free(osd_data->pages, ceph_wb_pagevec_pool);
 
 786	else
 787		kfree(osd_data->pages);
 788	ceph_osdc_put_request(req);
 789}
 790
 791/*
 792 * initiate async writeback
 793 */
 794static int ceph_writepages_start(struct address_space *mapping,
 795				 struct writeback_control *wbc)
 796{
 797	struct inode *inode = mapping->host;
 798	struct ceph_inode_info *ci = ceph_inode(inode);
 799	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 800	struct ceph_vino vino = ceph_vino(inode);
 801	pgoff_t index, start_index, end = -1;
 802	struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc;
 803	struct pagevec pvec;
 804	int rc = 0;
 805	unsigned int wsize = i_blocksize(inode);
 806	struct ceph_osd_request *req = NULL;
 807	struct ceph_writeback_ctl ceph_wbc;
 808	bool should_loop, range_whole = false;
 809	bool done = false;
 810	bool caching = ceph_is_cache_enabled(inode);
 811
 812	if (wbc->sync_mode == WB_SYNC_NONE &&
 813	    fsc->write_congested)
 814		return 0;
 815
 816	dout("writepages_start %p (mode=%s)\n", inode,
 817	     wbc->sync_mode == WB_SYNC_NONE ? "NONE" :
 818	     (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD"));
 819
 820	if (ceph_inode_is_shutdown(inode)) {
 821		if (ci->i_wrbuffer_ref > 0) {
 822			pr_warn_ratelimited(
 823				"writepage_start %p %lld forced umount\n",
 824				inode, ceph_ino(inode));
 825		}
 826		mapping_set_error(mapping, -EIO);
 827		return -EIO; /* we're in a forced umount, don't write! */
 828	}
 829	if (fsc->mount_options->wsize < wsize)
 830		wsize = fsc->mount_options->wsize;
 831
 832	pagevec_init(&pvec);
 833
 834	start_index = wbc->range_cyclic ? mapping->writeback_index : 0;
 835	index = start_index;
 836
 837retry:
 838	/* find oldest snap context with dirty data */
 839	snapc = get_oldest_context(inode, &ceph_wbc, NULL);
 840	if (!snapc) {
 841		/* hmm, why does writepages get called when there
 842		   is no dirty data? */
 843		dout(" no snap context with dirty data?\n");
 844		goto out;
 845	}
 846	dout(" oldest snapc is %p seq %lld (%d snaps)\n",
 847	     snapc, snapc->seq, snapc->num_snaps);
 848
 849	should_loop = false;
 850	if (ceph_wbc.head_snapc && snapc != last_snapc) {
 851		/* where to start/end? */
 852		if (wbc->range_cyclic) {
 853			index = start_index;
 854			end = -1;
 855			if (index > 0)
 856				should_loop = true;
 857			dout(" cyclic, start at %lu\n", index);
 858		} else {
 859			index = wbc->range_start >> PAGE_SHIFT;
 860			end = wbc->range_end >> PAGE_SHIFT;
 861			if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
 862				range_whole = true;
 863			dout(" not cyclic, %lu to %lu\n", index, end);
 864		}
 865	} else if (!ceph_wbc.head_snapc) {
 866		/* Do not respect wbc->range_{start,end}. Dirty pages
 867		 * in that range can be associated with newer snapc.
 868		 * They are not writeable until we write all dirty pages
 869		 * associated with 'snapc' get written */
 870		if (index > 0)
 871			should_loop = true;
 872		dout(" non-head snapc, range whole\n");
 873	}
 874
 875	ceph_put_snap_context(last_snapc);
 876	last_snapc = snapc;
 877
 878	while (!done && index <= end) {
 879		int num_ops = 0, op_idx;
 880		unsigned i, pvec_pages, max_pages, locked_pages = 0;
 881		struct page **pages = NULL, **data_pages;
 
 882		struct page *page;
 883		pgoff_t strip_unit_end = 0;
 884		u64 offset = 0, len = 0;
 885		bool from_pool = false;
 886
 887		max_pages = wsize >> PAGE_SHIFT;
 888
 889get_more_pages:
 890		pvec_pages = pagevec_lookup_range_tag(&pvec, mapping, &index,
 891						end, PAGECACHE_TAG_DIRTY);
 
 892		dout("pagevec_lookup_range_tag got %d\n", pvec_pages);
 893		if (!pvec_pages && !locked_pages)
 894			break;
 895		for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) {
 896			page = pvec.pages[i];
 897			dout("? %p idx %lu\n", page, page->index);
 898			if (locked_pages == 0)
 899				lock_page(page);  /* first page */
 900			else if (!trylock_page(page))
 901				break;
 902
 903			/* only dirty pages, or our accounting breaks */
 904			if (unlikely(!PageDirty(page)) ||
 905			    unlikely(page->mapping != mapping)) {
 906				dout("!dirty or !mapping %p\n", page);
 907				unlock_page(page);
 908				continue;
 909			}
 910			/* only if matching snap context */
 911			pgsnapc = page_snap_context(page);
 912			if (pgsnapc != snapc) {
 913				dout("page snapc %p %lld != oldest %p %lld\n",
 914				     pgsnapc, pgsnapc->seq, snapc, snapc->seq);
 915				if (!should_loop &&
 916				    !ceph_wbc.head_snapc &&
 917				    wbc->sync_mode != WB_SYNC_NONE)
 918					should_loop = true;
 919				unlock_page(page);
 920				continue;
 921			}
 922			if (page_offset(page) >= ceph_wbc.i_size) {
 923				struct folio *folio = page_folio(page);
 924
 925				dout("folio at %lu beyond eof %llu\n",
 926				     folio->index, ceph_wbc.i_size);
 927				if ((ceph_wbc.size_stable ||
 928				    folio_pos(folio) >= i_size_read(inode)) &&
 929				    folio_clear_dirty_for_io(folio))
 930					folio_invalidate(folio, 0,
 931							folio_size(folio));
 932				folio_unlock(folio);
 933				continue;
 934			}
 935			if (strip_unit_end && (page->index > strip_unit_end)) {
 936				dout("end of strip unit %p\n", page);
 937				unlock_page(page);
 938				break;
 939			}
 940			if (PageWriteback(page) || PageFsCache(page)) {
 941				if (wbc->sync_mode == WB_SYNC_NONE) {
 942					dout("%p under writeback\n", page);
 943					unlock_page(page);
 944					continue;
 945				}
 946				dout("waiting on writeback %p\n", page);
 947				wait_on_page_writeback(page);
 948				wait_on_page_fscache(page);
 949			}
 950
 951			if (!clear_page_dirty_for_io(page)) {
 952				dout("%p !clear_page_dirty_for_io\n", page);
 953				unlock_page(page);
 954				continue;
 955			}
 956
 957			/*
 958			 * We have something to write.  If this is
 959			 * the first locked page this time through,
 960			 * calculate max possinle write size and
 961			 * allocate a page array
 962			 */
 963			if (locked_pages == 0) {
 964				u64 objnum;
 965				u64 objoff;
 966				u32 xlen;
 967
 968				/* prepare async write request */
 969				offset = (u64)page_offset(page);
 970				ceph_calc_file_object_mapping(&ci->i_layout,
 971							      offset, wsize,
 972							      &objnum, &objoff,
 973							      &xlen);
 974				len = xlen;
 975
 976				num_ops = 1;
 977				strip_unit_end = page->index +
 978					((len - 1) >> PAGE_SHIFT);
 979
 980				BUG_ON(pages);
 981				max_pages = calc_pages_for(0, (u64)len);
 982				pages = kmalloc_array(max_pages,
 983						      sizeof(*pages),
 984						      GFP_NOFS);
 985				if (!pages) {
 986					from_pool = true;
 987					pages = mempool_alloc(ceph_wb_pagevec_pool, GFP_NOFS);
 988					BUG_ON(!pages);
 989				}
 990
 991				len = 0;
 992			} else if (page->index !=
 993				   (offset + len) >> PAGE_SHIFT) {
 994				if (num_ops >= (from_pool ?  CEPH_OSD_SLAB_OPS :
 995							     CEPH_OSD_MAX_OPS)) {
 996					redirty_page_for_writepage(wbc, page);
 997					unlock_page(page);
 998					break;
 999				}
1000
1001				num_ops++;
1002				offset = (u64)page_offset(page);
1003				len = 0;
1004			}
1005
1006			/* note position of first page in pvec */
1007			dout("%p will write page %p idx %lu\n",
1008			     inode, page, page->index);
1009
1010			if (atomic_long_inc_return(&fsc->writeback_count) >
1011			    CONGESTION_ON_THRESH(
1012				    fsc->mount_options->congestion_kb))
1013				fsc->write_congested = true;
 
 
 
1014
1015			pages[locked_pages++] = page;
1016			pvec.pages[i] = NULL;
1017
1018			len += thp_size(page);
1019		}
1020
1021		/* did we get anything? */
1022		if (!locked_pages)
1023			goto release_pvec_pages;
1024		if (i) {
1025			unsigned j, n = 0;
1026			/* shift unused page to beginning of pvec */
1027			for (j = 0; j < pvec_pages; j++) {
1028				if (!pvec.pages[j])
1029					continue;
1030				if (n < j)
1031					pvec.pages[n] = pvec.pages[j];
1032				n++;
1033			}
1034			pvec.nr = n;
1035
1036			if (pvec_pages && i == pvec_pages &&
1037			    locked_pages < max_pages) {
1038				dout("reached end pvec, trying for more\n");
1039				pagevec_release(&pvec);
1040				goto get_more_pages;
1041			}
1042		}
1043
1044new_request:
1045		offset = page_offset(pages[0]);
1046		len = wsize;
1047
1048		req = ceph_osdc_new_request(&fsc->client->osdc,
1049					&ci->i_layout, vino,
1050					offset, &len, 0, num_ops,
1051					CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE,
1052					snapc, ceph_wbc.truncate_seq,
1053					ceph_wbc.truncate_size, false);
1054		if (IS_ERR(req)) {
1055			req = ceph_osdc_new_request(&fsc->client->osdc,
1056						&ci->i_layout, vino,
1057						offset, &len, 0,
1058						min(num_ops,
1059						    CEPH_OSD_SLAB_OPS),
1060						CEPH_OSD_OP_WRITE,
1061						CEPH_OSD_FLAG_WRITE,
1062						snapc, ceph_wbc.truncate_seq,
1063						ceph_wbc.truncate_size, true);
1064			BUG_ON(IS_ERR(req));
1065		}
1066		BUG_ON(len < page_offset(pages[locked_pages - 1]) +
1067			     thp_size(page) - offset);
1068
1069		req->r_callback = writepages_finish;
1070		req->r_inode = inode;
1071
1072		/* Format the osd request message and submit the write */
1073		len = 0;
1074		data_pages = pages;
1075		op_idx = 0;
1076		for (i = 0; i < locked_pages; i++) {
1077			u64 cur_offset = page_offset(pages[i]);
1078			/*
1079			 * Discontinuity in page range? Ceph can handle that by just passing
1080			 * multiple extents in the write op.
1081			 */
1082			if (offset + len != cur_offset) {
1083				/* If it's full, stop here */
1084				if (op_idx + 1 == req->r_num_ops)
1085					break;
1086
1087				/* Kick off an fscache write with what we have so far. */
1088				ceph_fscache_write_to_cache(inode, offset, len, caching);
1089
1090				/* Start a new extent */
1091				osd_req_op_extent_dup_last(req, op_idx,
1092							   cur_offset - offset);
1093				dout("writepages got pages at %llu~%llu\n",
1094				     offset, len);
1095				osd_req_op_extent_osd_data_pages(req, op_idx,
1096							data_pages, len, 0,
1097							from_pool, false);
1098				osd_req_op_extent_update(req, op_idx, len);
1099
1100				len = 0;
1101				offset = cur_offset;
1102				data_pages = pages + i;
1103				op_idx++;
1104			}
1105
1106			set_page_writeback(pages[i]);
1107			if (caching)
1108				ceph_set_page_fscache(pages[i]);
1109			len += thp_size(page);
1110		}
1111		ceph_fscache_write_to_cache(inode, offset, len, caching);
1112
1113		if (ceph_wbc.size_stable) {
1114			len = min(len, ceph_wbc.i_size - offset);
1115		} else if (i == locked_pages) {
1116			/* writepages_finish() clears writeback pages
1117			 * according to the data length, so make sure
1118			 * data length covers all locked pages */
1119			u64 min_len = len + 1 - thp_size(page);
1120			len = get_writepages_data_length(inode, pages[i - 1],
1121							 offset);
1122			len = max(len, min_len);
1123		}
1124		dout("writepages got pages at %llu~%llu\n", offset, len);
1125
1126		osd_req_op_extent_osd_data_pages(req, op_idx, data_pages, len,
1127						 0, from_pool, false);
1128		osd_req_op_extent_update(req, op_idx, len);
1129
1130		BUG_ON(op_idx + 1 != req->r_num_ops);
1131
1132		from_pool = false;
1133		if (i < locked_pages) {
1134			BUG_ON(num_ops <= req->r_num_ops);
1135			num_ops -= req->r_num_ops;
1136			locked_pages -= i;
1137
1138			/* allocate new pages array for next request */
1139			data_pages = pages;
1140			pages = kmalloc_array(locked_pages, sizeof(*pages),
1141					      GFP_NOFS);
1142			if (!pages) {
1143				from_pool = true;
1144				pages = mempool_alloc(ceph_wb_pagevec_pool, GFP_NOFS);
1145				BUG_ON(!pages);
1146			}
1147			memcpy(pages, data_pages + i,
1148			       locked_pages * sizeof(*pages));
1149			memset(data_pages + i, 0,
1150			       locked_pages * sizeof(*pages));
1151		} else {
1152			BUG_ON(num_ops != req->r_num_ops);
1153			index = pages[i - 1]->index + 1;
1154			/* request message now owns the pages array */
1155			pages = NULL;
1156		}
1157
1158		req->r_mtime = inode->i_mtime;
1159		ceph_osdc_start_request(&fsc->client->osdc, req);
 
1160		req = NULL;
1161
1162		wbc->nr_to_write -= i;
1163		if (pages)
1164			goto new_request;
1165
1166		/*
1167		 * We stop writing back only if we are not doing
1168		 * integrity sync. In case of integrity sync we have to
1169		 * keep going until we have written all the pages
1170		 * we tagged for writeback prior to entering this loop.
1171		 */
1172		if (wbc->nr_to_write <= 0 && wbc->sync_mode == WB_SYNC_NONE)
1173			done = true;
1174
1175release_pvec_pages:
1176		dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr,
1177		     pvec.nr ? pvec.pages[0] : NULL);
1178		pagevec_release(&pvec);
1179	}
1180
1181	if (should_loop && !done) {
1182		/* more to do; loop back to beginning of file */
1183		dout("writepages looping back to beginning of file\n");
1184		end = start_index - 1; /* OK even when start_index == 0 */
1185
1186		/* to write dirty pages associated with next snapc,
1187		 * we need to wait until current writes complete */
1188		if (wbc->sync_mode != WB_SYNC_NONE &&
1189		    start_index == 0 && /* all dirty pages were checked */
1190		    !ceph_wbc.head_snapc) {
1191			struct page *page;
1192			unsigned i, nr;
1193			index = 0;
1194			while ((index <= end) &&
1195			       (nr = pagevec_lookup_tag(&pvec, mapping, &index,
1196						PAGECACHE_TAG_WRITEBACK))) {
1197				for (i = 0; i < nr; i++) {
1198					page = pvec.pages[i];
1199					if (page_snap_context(page) != snapc)
1200						continue;
1201					wait_on_page_writeback(page);
1202				}
1203				pagevec_release(&pvec);
1204				cond_resched();
1205			}
1206		}
1207
1208		start_index = 0;
1209		index = 0;
1210		goto retry;
1211	}
1212
1213	if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1214		mapping->writeback_index = index;
1215
1216out:
1217	ceph_osdc_put_request(req);
1218	ceph_put_snap_context(last_snapc);
1219	dout("writepages dend - startone, rc = %d\n", rc);
1220	return rc;
1221}
1222
1223
1224
1225/*
1226 * See if a given @snapc is either writeable, or already written.
1227 */
1228static int context_is_writeable_or_written(struct inode *inode,
1229					   struct ceph_snap_context *snapc)
1230{
1231	struct ceph_snap_context *oldest = get_oldest_context(inode, NULL, NULL);
1232	int ret = !oldest || snapc->seq <= oldest->seq;
1233
1234	ceph_put_snap_context(oldest);
1235	return ret;
1236}
1237
1238/**
1239 * ceph_find_incompatible - find an incompatible context and return it
1240 * @page: page being dirtied
1241 *
1242 * We are only allowed to write into/dirty a page if the page is
1243 * clean, or already dirty within the same snap context. Returns a
1244 * conflicting context if there is one, NULL if there isn't, or a
1245 * negative error code on other errors.
1246 *
1247 * Must be called with page lock held.
 
 
1248 */
1249static struct ceph_snap_context *
1250ceph_find_incompatible(struct page *page)
 
1251{
1252	struct inode *inode = page->mapping->host;
 
1253	struct ceph_inode_info *ci = ceph_inode(inode);
 
 
 
 
 
 
1254
1255	if (ceph_inode_is_shutdown(inode)) {
1256		dout(" page %p %llx:%llx is shutdown\n", page,
1257		     ceph_vinop(inode));
1258		return ERR_PTR(-ESTALE);
1259	}
1260
1261	for (;;) {
1262		struct ceph_snap_context *snapc, *oldest;
1263
1264		wait_on_page_writeback(page);
1265
1266		snapc = page_snap_context(page);
1267		if (!snapc || snapc == ci->i_head_snapc)
1268			break;
1269
 
 
1270		/*
1271		 * this page is already dirty in another (older) snap
1272		 * context!  is it writeable now?
1273		 */
1274		oldest = get_oldest_context(inode, NULL, NULL);
1275		if (snapc->seq > oldest->seq) {
1276			/* not writeable -- return it for the caller to deal with */
1277			ceph_put_snap_context(oldest);
1278			dout(" page %p snapc %p not current or oldest\n", page, snapc);
1279			return ceph_get_snap_context(snapc);
 
 
 
 
 
 
 
 
 
 
 
 
 
1280		}
1281		ceph_put_snap_context(oldest);
1282
1283		/* yay, writeable, do it now (without dropping page lock) */
1284		dout(" page %p snapc %p not current, but oldest\n", page, snapc);
1285		if (clear_page_dirty_for_io(page)) {
1286			int r = writepage_nounlock(page, NULL);
1287			if (r < 0)
1288				return ERR_PTR(r);
1289		}
 
 
1290	}
1291	return NULL;
1292}
1293
1294static int ceph_netfs_check_write_begin(struct file *file, loff_t pos, unsigned int len,
1295					struct folio **foliop, void **_fsdata)
1296{
1297	struct inode *inode = file_inode(file);
1298	struct ceph_inode_info *ci = ceph_inode(inode);
1299	struct ceph_snap_context *snapc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1300
1301	snapc = ceph_find_incompatible(folio_page(*foliop, 0));
1302	if (snapc) {
1303		int r;
1304
1305		folio_unlock(*foliop);
1306		folio_put(*foliop);
1307		*foliop = NULL;
1308		if (IS_ERR(snapc))
1309			return PTR_ERR(snapc);
1310
1311		ceph_queue_writeback(inode);
1312		r = wait_event_killable(ci->i_cap_wq,
1313					context_is_writeable_or_written(inode, snapc));
1314		ceph_put_snap_context(snapc);
1315		return r == 0 ? -EAGAIN : r;
1316	}
1317	return 0;
 
 
 
1318}
1319
1320/*
1321 * We are only allowed to write into/dirty the page if the page is
1322 * clean, or already dirty within the same snap context.
1323 */
1324static int ceph_write_begin(struct file *file, struct address_space *mapping,
1325			    loff_t pos, unsigned len,
1326			    struct page **pagep, void **fsdata)
1327{
1328	struct inode *inode = file_inode(file);
1329	struct ceph_inode_info *ci = ceph_inode(inode);
1330	struct folio *folio = NULL;
1331	int r;
1332
1333	r = netfs_write_begin(&ci->netfs, file, inode->i_mapping, pos, len, &folio, NULL);
1334	if (r < 0)
1335		return r;
1336
1337	folio_wait_fscache(folio);
1338	WARN_ON_ONCE(!folio_test_locked(folio));
1339	*pagep = &folio->page;
1340	return 0;
 
 
 
 
 
 
 
 
 
1341}
1342
1343/*
1344 * we don't do anything in here that simple_write_end doesn't do
1345 * except adjust dirty page accounting
1346 */
1347static int ceph_write_end(struct file *file, struct address_space *mapping,
1348			  loff_t pos, unsigned len, unsigned copied,
1349			  struct page *subpage, void *fsdata)
1350{
1351	struct folio *folio = page_folio(subpage);
1352	struct inode *inode = file_inode(file);
1353	bool check_cap = false;
1354
1355	dout("write_end file %p inode %p folio %p %d~%d (%d)\n", file,
1356	     inode, folio, (int)pos, (int)copied, (int)len);
1357
1358	if (!folio_test_uptodate(folio)) {
1359		/* just return that nothing was copied on a short copy */
1360		if (copied < len) {
1361			copied = 0;
1362			goto out;
1363		}
1364		folio_mark_uptodate(folio);
1365	}
1366
1367	/* did file size increase? */
1368	if (pos+copied > i_size_read(inode))
1369		check_cap = ceph_inode_set_size(inode, pos+copied);
1370
1371	folio_mark_dirty(folio);
1372
1373out:
1374	folio_unlock(folio);
1375	folio_put(folio);
1376
1377	if (check_cap)
1378		ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY);
1379
1380	return copied;
1381}
1382
 
 
 
 
 
 
 
 
 
 
 
1383const struct address_space_operations ceph_aops = {
1384	.read_folio = netfs_read_folio,
1385	.readahead = netfs_readahead,
1386	.writepage = ceph_writepage,
1387	.writepages = ceph_writepages_start,
1388	.write_begin = ceph_write_begin,
1389	.write_end = ceph_write_end,
1390	.dirty_folio = ceph_dirty_folio,
1391	.invalidate_folio = ceph_invalidate_folio,
1392	.release_folio = ceph_release_folio,
1393	.direct_IO = noop_direct_IO,
1394};
1395
1396static void ceph_block_sigs(sigset_t *oldset)
1397{
1398	sigset_t mask;
1399	siginitsetinv(&mask, sigmask(SIGKILL));
1400	sigprocmask(SIG_BLOCK, &mask, oldset);
1401}
1402
1403static void ceph_restore_sigs(sigset_t *oldset)
1404{
1405	sigprocmask(SIG_SETMASK, oldset, NULL);
1406}
1407
1408/*
1409 * vm ops
1410 */
1411static vm_fault_t ceph_filemap_fault(struct vm_fault *vmf)
1412{
1413	struct vm_area_struct *vma = vmf->vma;
1414	struct inode *inode = file_inode(vma->vm_file);
1415	struct ceph_inode_info *ci = ceph_inode(inode);
1416	struct ceph_file_info *fi = vma->vm_file->private_data;
1417	loff_t off = (loff_t)vmf->pgoff << PAGE_SHIFT;
 
1418	int want, got, err;
1419	sigset_t oldset;
1420	vm_fault_t ret = VM_FAULT_SIGBUS;
1421
1422	if (ceph_inode_is_shutdown(inode))
1423		return ret;
1424
1425	ceph_block_sigs(&oldset);
1426
1427	dout("filemap_fault %p %llx.%llx %llu trying to get caps\n",
1428	     inode, ceph_vinop(inode), off);
1429	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1430		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
1431	else
1432		want = CEPH_CAP_FILE_CACHE;
1433
1434	got = 0;
1435	err = ceph_get_caps(vma->vm_file, CEPH_CAP_FILE_RD, want, -1, &got);
 
1436	if (err < 0)
1437		goto out_restore;
1438
1439	dout("filemap_fault %p %llu got cap refs on %s\n",
1440	     inode, off, ceph_cap_string(got));
1441
1442	if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) ||
1443	    !ceph_has_inline_data(ci)) {
1444		CEPH_DEFINE_RW_CONTEXT(rw_ctx, got);
1445		ceph_add_rw_context(fi, &rw_ctx);
1446		ret = filemap_fault(vmf);
1447		ceph_del_rw_context(fi, &rw_ctx);
1448		dout("filemap_fault %p %llu drop cap refs %s ret %x\n",
1449		     inode, off, ceph_cap_string(got), ret);
 
1450	} else
1451		err = -EAGAIN;
1452
 
 
1453	ceph_put_cap_refs(ci, got);
1454
1455	if (err != -EAGAIN)
1456		goto out_restore;
1457
1458	/* read inline data */
1459	if (off >= PAGE_SIZE) {
1460		/* does not support inline data > PAGE_SIZE */
1461		ret = VM_FAULT_SIGBUS;
1462	} else {
1463		struct address_space *mapping = inode->i_mapping;
1464		struct page *page;
1465
1466		filemap_invalidate_lock_shared(mapping);
1467		page = find_or_create_page(mapping, 0,
1468				mapping_gfp_constraint(mapping, ~__GFP_FS));
1469		if (!page) {
1470			ret = VM_FAULT_OOM;
1471			goto out_inline;
1472		}
1473		err = __ceph_do_getattr(inode, page,
1474					 CEPH_STAT_CAP_INLINE_DATA, true);
1475		if (err < 0 || off >= i_size_read(inode)) {
1476			unlock_page(page);
1477			put_page(page);
1478			ret = vmf_error(err);
1479			goto out_inline;
1480		}
1481		if (err < PAGE_SIZE)
1482			zero_user_segment(page, err, PAGE_SIZE);
1483		else
1484			flush_dcache_page(page);
1485		SetPageUptodate(page);
1486		vmf->page = page;
1487		ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED;
1488out_inline:
1489		filemap_invalidate_unlock_shared(mapping);
1490		dout("filemap_fault %p %llu read inline data ret %x\n",
1491		     inode, off, ret);
1492	}
1493out_restore:
1494	ceph_restore_sigs(&oldset);
1495	if (err < 0)
1496		ret = vmf_error(err);
1497
1498	return ret;
1499}
1500
 
 
 
1501static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
1502{
1503	struct vm_area_struct *vma = vmf->vma;
1504	struct inode *inode = file_inode(vma->vm_file);
1505	struct ceph_inode_info *ci = ceph_inode(inode);
1506	struct ceph_file_info *fi = vma->vm_file->private_data;
1507	struct ceph_cap_flush *prealloc_cf;
1508	struct page *page = vmf->page;
1509	loff_t off = page_offset(page);
1510	loff_t size = i_size_read(inode);
1511	size_t len;
1512	int want, got, err;
1513	sigset_t oldset;
1514	vm_fault_t ret = VM_FAULT_SIGBUS;
1515
1516	if (ceph_inode_is_shutdown(inode))
1517		return ret;
1518
1519	prealloc_cf = ceph_alloc_cap_flush();
1520	if (!prealloc_cf)
1521		return VM_FAULT_OOM;
1522
1523	sb_start_pagefault(inode->i_sb);
1524	ceph_block_sigs(&oldset);
1525
1526	if (off + thp_size(page) <= size)
1527		len = thp_size(page);
 
 
 
 
 
 
 
 
 
 
 
 
 
1528	else
1529		len = offset_in_thp(page, size);
1530
1531	dout("page_mkwrite %p %llx.%llx %llu~%zd getting caps i_size %llu\n",
1532	     inode, ceph_vinop(inode), off, len, size);
1533	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1534		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1535	else
1536		want = CEPH_CAP_FILE_BUFFER;
1537
1538	got = 0;
1539	err = ceph_get_caps(vma->vm_file, CEPH_CAP_FILE_WR, want, off + len, &got);
 
1540	if (err < 0)
1541		goto out_free;
1542
1543	dout("page_mkwrite %p %llu~%zd got cap refs on %s\n",
1544	     inode, off, len, ceph_cap_string(got));
1545
1546	/* Update time before taking page lock */
1547	file_update_time(vma->vm_file);
1548	inode_inc_iversion_raw(inode);
1549
1550	do {
1551		struct ceph_snap_context *snapc;
1552
1553		lock_page(page);
1554
1555		if (page_mkwrite_check_truncate(page, inode) < 0) {
1556			unlock_page(page);
1557			ret = VM_FAULT_NOPAGE;
1558			break;
1559		}
1560
1561		snapc = ceph_find_incompatible(page);
1562		if (!snapc) {
1563			/* success.  we'll keep the page locked. */
1564			set_page_dirty(page);
1565			ret = VM_FAULT_LOCKED;
1566			break;
1567		}
1568
1569		unlock_page(page);
1570
1571		if (IS_ERR(snapc)) {
1572			ret = VM_FAULT_SIGBUS;
1573			break;
1574		}
 
1575
1576		ceph_queue_writeback(inode);
1577		err = wait_event_killable(ci->i_cap_wq,
1578				context_is_writeable_or_written(inode, snapc));
1579		ceph_put_snap_context(snapc);
1580	} while (err == 0);
1581
1582	if (ret == VM_FAULT_LOCKED) {
1583		int dirty;
1584		spin_lock(&ci->i_ceph_lock);
 
1585		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1586					       &prealloc_cf);
1587		spin_unlock(&ci->i_ceph_lock);
1588		if (dirty)
1589			__mark_inode_dirty(inode, dirty);
1590	}
1591
1592	dout("page_mkwrite %p %llu~%zd dropping cap refs on %s ret %x\n",
1593	     inode, off, len, ceph_cap_string(got), ret);
1594	ceph_put_cap_refs_async(ci, got);
1595out_free:
1596	ceph_restore_sigs(&oldset);
1597	sb_end_pagefault(inode->i_sb);
1598	ceph_free_cap_flush(prealloc_cf);
1599	if (err < 0)
1600		ret = vmf_error(err);
1601	return ret;
1602}
1603
1604void ceph_fill_inline_data(struct inode *inode, struct page *locked_page,
1605			   char	*data, size_t len)
1606{
1607	struct address_space *mapping = inode->i_mapping;
1608	struct page *page;
1609
1610	if (locked_page) {
1611		page = locked_page;
1612	} else {
1613		if (i_size_read(inode) == 0)
1614			return;
1615		page = find_or_create_page(mapping, 0,
1616					   mapping_gfp_constraint(mapping,
1617					   ~__GFP_FS));
1618		if (!page)
1619			return;
1620		if (PageUptodate(page)) {
1621			unlock_page(page);
1622			put_page(page);
1623			return;
1624		}
1625	}
1626
1627	dout("fill_inline_data %p %llx.%llx len %zu locked_page %p\n",
1628	     inode, ceph_vinop(inode), len, locked_page);
1629
1630	if (len > 0) {
1631		void *kaddr = kmap_atomic(page);
1632		memcpy(kaddr, data, len);
1633		kunmap_atomic(kaddr);
1634	}
1635
1636	if (page != locked_page) {
1637		if (len < PAGE_SIZE)
1638			zero_user_segment(page, len, PAGE_SIZE);
1639		else
1640			flush_dcache_page(page);
1641
1642		SetPageUptodate(page);
1643		unlock_page(page);
1644		put_page(page);
1645	}
1646}
1647
1648int ceph_uninline_data(struct file *file)
1649{
1650	struct inode *inode = file_inode(file);
1651	struct ceph_inode_info *ci = ceph_inode(inode);
1652	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1653	struct ceph_osd_request *req = NULL;
1654	struct ceph_cap_flush *prealloc_cf = NULL;
1655	struct folio *folio = NULL;
1656	u64 inline_version = CEPH_INLINE_NONE;
1657	struct page *pages[1];
1658	int err = 0;
1659	u64 len;
1660
1661	spin_lock(&ci->i_ceph_lock);
1662	inline_version = ci->i_inline_version;
1663	spin_unlock(&ci->i_ceph_lock);
1664
1665	dout("uninline_data %p %llx.%llx inline_version %llu\n",
1666	     inode, ceph_vinop(inode), inline_version);
1667
1668	if (ceph_inode_is_shutdown(inode)) {
1669		err = -EIO;
1670		goto out;
1671	}
1672
1673	if (inline_version == CEPH_INLINE_NONE)
1674		return 0;
1675
1676	prealloc_cf = ceph_alloc_cap_flush();
1677	if (!prealloc_cf)
1678		return -ENOMEM;
1679
1680	if (inline_version == 1) /* initial version, no data */
1681		goto out_uninline;
1682
1683	folio = read_mapping_folio(inode->i_mapping, 0, file);
1684	if (IS_ERR(folio)) {
1685		err = PTR_ERR(folio);
1686		goto out;
 
 
 
 
1687	}
1688
1689	folio_lock(folio);
1690
1691	len = i_size_read(inode);
1692	if (len > folio_size(folio))
1693		len = folio_size(folio);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1694
1695	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1696				    ceph_vino(inode), 0, &len, 0, 1,
1697				    CEPH_OSD_OP_CREATE, CEPH_OSD_FLAG_WRITE,
1698				    NULL, 0, 0, false);
1699	if (IS_ERR(req)) {
1700		err = PTR_ERR(req);
1701		goto out_unlock;
1702	}
1703
1704	req->r_mtime = inode->i_mtime;
1705	ceph_osdc_start_request(&fsc->client->osdc, req);
1706	err = ceph_osdc_wait_request(&fsc->client->osdc, req);
 
1707	ceph_osdc_put_request(req);
1708	if (err < 0)
1709		goto out_unlock;
1710
1711	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1712				    ceph_vino(inode), 0, &len, 1, 3,
1713				    CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE,
1714				    NULL, ci->i_truncate_seq,
1715				    ci->i_truncate_size, false);
1716	if (IS_ERR(req)) {
1717		err = PTR_ERR(req);
1718		goto out_unlock;
1719	}
1720
1721	pages[0] = folio_page(folio, 0);
1722	osd_req_op_extent_osd_data_pages(req, 1, pages, len, 0, false, false);
1723
1724	{
1725		__le64 xattr_buf = cpu_to_le64(inline_version);
1726		err = osd_req_op_xattr_init(req, 0, CEPH_OSD_OP_CMPXATTR,
1727					    "inline_version", &xattr_buf,
1728					    sizeof(xattr_buf),
1729					    CEPH_OSD_CMPXATTR_OP_GT,
1730					    CEPH_OSD_CMPXATTR_MODE_U64);
1731		if (err)
1732			goto out_put_req;
1733	}
1734
1735	{
1736		char xattr_buf[32];
1737		int xattr_len = snprintf(xattr_buf, sizeof(xattr_buf),
1738					 "%llu", inline_version);
1739		err = osd_req_op_xattr_init(req, 2, CEPH_OSD_OP_SETXATTR,
1740					    "inline_version",
1741					    xattr_buf, xattr_len, 0, 0);
1742		if (err)
1743			goto out_put_req;
1744	}
1745
1746	req->r_mtime = inode->i_mtime;
1747	ceph_osdc_start_request(&fsc->client->osdc, req);
1748	err = ceph_osdc_wait_request(&fsc->client->osdc, req);
1749
1750	ceph_update_write_metrics(&fsc->mdsc->metric, req->r_start_latency,
1751				  req->r_end_latency, len, err);
1752
1753out_uninline:
1754	if (!err) {
1755		int dirty;
1756
1757		/* Set to CAP_INLINE_NONE and dirty the caps */
1758		down_read(&fsc->mdsc->snap_rwsem);
1759		spin_lock(&ci->i_ceph_lock);
1760		ci->i_inline_version = CEPH_INLINE_NONE;
1761		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR, &prealloc_cf);
1762		spin_unlock(&ci->i_ceph_lock);
1763		up_read(&fsc->mdsc->snap_rwsem);
1764		if (dirty)
1765			__mark_inode_dirty(inode, dirty);
1766	}
1767out_put_req:
1768	ceph_osdc_put_request(req);
1769	if (err == -ECANCELED)
1770		err = 0;
1771out_unlock:
1772	if (folio) {
1773		folio_unlock(folio);
1774		folio_put(folio);
1775	}
1776out:
1777	ceph_free_cap_flush(prealloc_cf);
 
 
 
 
 
 
 
1778	dout("uninline_data %p %llx.%llx inline_version %llu = %d\n",
1779	     inode, ceph_vinop(inode), inline_version, err);
1780	return err;
1781}
1782
1783static const struct vm_operations_struct ceph_vmops = {
1784	.fault		= ceph_filemap_fault,
1785	.page_mkwrite	= ceph_page_mkwrite,
1786};
1787
1788int ceph_mmap(struct file *file, struct vm_area_struct *vma)
1789{
1790	struct address_space *mapping = file->f_mapping;
1791
1792	if (!mapping->a_ops->read_folio)
1793		return -ENOEXEC;
 
1794	vma->vm_ops = &ceph_vmops;
1795	return 0;
1796}
1797
1798enum {
1799	POOL_READ	= 1,
1800	POOL_WRITE	= 2,
1801};
1802
1803static int __ceph_pool_perm_get(struct ceph_inode_info *ci,
1804				s64 pool, struct ceph_string *pool_ns)
1805{
1806	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->netfs.inode);
1807	struct ceph_mds_client *mdsc = fsc->mdsc;
1808	struct ceph_osd_request *rd_req = NULL, *wr_req = NULL;
1809	struct rb_node **p, *parent;
1810	struct ceph_pool_perm *perm;
1811	struct page **pages;
1812	size_t pool_ns_len;
1813	int err = 0, err2 = 0, have = 0;
1814
1815	down_read(&mdsc->pool_perm_rwsem);
1816	p = &mdsc->pool_perm_tree.rb_node;
1817	while (*p) {
1818		perm = rb_entry(*p, struct ceph_pool_perm, node);
1819		if (pool < perm->pool)
1820			p = &(*p)->rb_left;
1821		else if (pool > perm->pool)
1822			p = &(*p)->rb_right;
1823		else {
1824			int ret = ceph_compare_string(pool_ns,
1825						perm->pool_ns,
1826						perm->pool_ns_len);
1827			if (ret < 0)
1828				p = &(*p)->rb_left;
1829			else if (ret > 0)
1830				p = &(*p)->rb_right;
1831			else {
1832				have = perm->perm;
1833				break;
1834			}
1835		}
1836	}
1837	up_read(&mdsc->pool_perm_rwsem);
1838	if (*p)
1839		goto out;
1840
1841	if (pool_ns)
1842		dout("__ceph_pool_perm_get pool %lld ns %.*s no perm cached\n",
1843		     pool, (int)pool_ns->len, pool_ns->str);
1844	else
1845		dout("__ceph_pool_perm_get pool %lld no perm cached\n", pool);
1846
1847	down_write(&mdsc->pool_perm_rwsem);
1848	p = &mdsc->pool_perm_tree.rb_node;
1849	parent = NULL;
1850	while (*p) {
1851		parent = *p;
1852		perm = rb_entry(parent, struct ceph_pool_perm, node);
1853		if (pool < perm->pool)
1854			p = &(*p)->rb_left;
1855		else if (pool > perm->pool)
1856			p = &(*p)->rb_right;
1857		else {
1858			int ret = ceph_compare_string(pool_ns,
1859						perm->pool_ns,
1860						perm->pool_ns_len);
1861			if (ret < 0)
1862				p = &(*p)->rb_left;
1863			else if (ret > 0)
1864				p = &(*p)->rb_right;
1865			else {
1866				have = perm->perm;
1867				break;
1868			}
1869		}
1870	}
1871	if (*p) {
1872		up_write(&mdsc->pool_perm_rwsem);
1873		goto out;
1874	}
1875
1876	rd_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL,
1877					 1, false, GFP_NOFS);
1878	if (!rd_req) {
1879		err = -ENOMEM;
1880		goto out_unlock;
1881	}
1882
1883	rd_req->r_flags = CEPH_OSD_FLAG_READ;
1884	osd_req_op_init(rd_req, 0, CEPH_OSD_OP_STAT, 0);
1885	rd_req->r_base_oloc.pool = pool;
1886	if (pool_ns)
1887		rd_req->r_base_oloc.pool_ns = ceph_get_string(pool_ns);
1888	ceph_oid_printf(&rd_req->r_base_oid, "%llx.00000000", ci->i_vino.ino);
1889
1890	err = ceph_osdc_alloc_messages(rd_req, GFP_NOFS);
1891	if (err)
1892		goto out_unlock;
1893
1894	wr_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL,
1895					 1, false, GFP_NOFS);
1896	if (!wr_req) {
1897		err = -ENOMEM;
1898		goto out_unlock;
1899	}
1900
1901	wr_req->r_flags = CEPH_OSD_FLAG_WRITE;
1902	osd_req_op_init(wr_req, 0, CEPH_OSD_OP_CREATE, CEPH_OSD_OP_FLAG_EXCL);
1903	ceph_oloc_copy(&wr_req->r_base_oloc, &rd_req->r_base_oloc);
1904	ceph_oid_copy(&wr_req->r_base_oid, &rd_req->r_base_oid);
1905
1906	err = ceph_osdc_alloc_messages(wr_req, GFP_NOFS);
1907	if (err)
1908		goto out_unlock;
1909
1910	/* one page should be large enough for STAT data */
1911	pages = ceph_alloc_page_vector(1, GFP_KERNEL);
1912	if (IS_ERR(pages)) {
1913		err = PTR_ERR(pages);
1914		goto out_unlock;
1915	}
1916
1917	osd_req_op_raw_data_in_pages(rd_req, 0, pages, PAGE_SIZE,
1918				     0, false, true);
1919	ceph_osdc_start_request(&fsc->client->osdc, rd_req);
1920
1921	wr_req->r_mtime = ci->netfs.inode.i_mtime;
1922	ceph_osdc_start_request(&fsc->client->osdc, wr_req);
1923
1924	err = ceph_osdc_wait_request(&fsc->client->osdc, rd_req);
1925	err2 = ceph_osdc_wait_request(&fsc->client->osdc, wr_req);
 
 
1926
1927	if (err >= 0 || err == -ENOENT)
1928		have |= POOL_READ;
1929	else if (err != -EPERM) {
1930		if (err == -EBLOCKLISTED)
1931			fsc->blocklisted = true;
1932		goto out_unlock;
1933	}
1934
1935	if (err2 == 0 || err2 == -EEXIST)
1936		have |= POOL_WRITE;
1937	else if (err2 != -EPERM) {
1938		if (err2 == -EBLOCKLISTED)
1939			fsc->blocklisted = true;
1940		err = err2;
1941		goto out_unlock;
1942	}
1943
1944	pool_ns_len = pool_ns ? pool_ns->len : 0;
1945	perm = kmalloc(sizeof(*perm) + pool_ns_len + 1, GFP_NOFS);
1946	if (!perm) {
1947		err = -ENOMEM;
1948		goto out_unlock;
1949	}
1950
1951	perm->pool = pool;
1952	perm->perm = have;
1953	perm->pool_ns_len = pool_ns_len;
1954	if (pool_ns_len > 0)
1955		memcpy(perm->pool_ns, pool_ns->str, pool_ns_len);
1956	perm->pool_ns[pool_ns_len] = 0;
1957
1958	rb_link_node(&perm->node, parent, p);
1959	rb_insert_color(&perm->node, &mdsc->pool_perm_tree);
1960	err = 0;
1961out_unlock:
1962	up_write(&mdsc->pool_perm_rwsem);
1963
1964	ceph_osdc_put_request(rd_req);
1965	ceph_osdc_put_request(wr_req);
1966out:
1967	if (!err)
1968		err = have;
1969	if (pool_ns)
1970		dout("__ceph_pool_perm_get pool %lld ns %.*s result = %d\n",
1971		     pool, (int)pool_ns->len, pool_ns->str, err);
1972	else
1973		dout("__ceph_pool_perm_get pool %lld result = %d\n", pool, err);
1974	return err;
1975}
1976
1977int ceph_pool_perm_check(struct inode *inode, int need)
1978{
1979	struct ceph_inode_info *ci = ceph_inode(inode);
1980	struct ceph_string *pool_ns;
1981	s64 pool;
1982	int ret, flags;
1983
1984	/* Only need to do this for regular files */
1985	if (!S_ISREG(inode->i_mode))
1986		return 0;
1987
1988	if (ci->i_vino.snap != CEPH_NOSNAP) {
1989		/*
1990		 * Pool permission check needs to write to the first object.
1991		 * But for snapshot, head of the first object may have alread
1992		 * been deleted. Skip check to avoid creating orphan object.
1993		 */
1994		return 0;
1995	}
1996
1997	if (ceph_test_mount_opt(ceph_inode_to_client(inode),
1998				NOPOOLPERM))
1999		return 0;
2000
2001	spin_lock(&ci->i_ceph_lock);
2002	flags = ci->i_ceph_flags;
2003	pool = ci->i_layout.pool_id;
2004	spin_unlock(&ci->i_ceph_lock);
2005check:
2006	if (flags & CEPH_I_POOL_PERM) {
2007		if ((need & CEPH_CAP_FILE_RD) && !(flags & CEPH_I_POOL_RD)) {
2008			dout("ceph_pool_perm_check pool %lld no read perm\n",
2009			     pool);
2010			return -EPERM;
2011		}
2012		if ((need & CEPH_CAP_FILE_WR) && !(flags & CEPH_I_POOL_WR)) {
2013			dout("ceph_pool_perm_check pool %lld no write perm\n",
2014			     pool);
2015			return -EPERM;
2016		}
2017		return 0;
2018	}
2019
2020	pool_ns = ceph_try_get_string(ci->i_layout.pool_ns);
2021	ret = __ceph_pool_perm_get(ci, pool, pool_ns);
2022	ceph_put_string(pool_ns);
2023	if (ret < 0)
2024		return ret;
2025
2026	flags = CEPH_I_POOL_PERM;
2027	if (ret & POOL_READ)
2028		flags |= CEPH_I_POOL_RD;
2029	if (ret & POOL_WRITE)
2030		flags |= CEPH_I_POOL_WR;
2031
2032	spin_lock(&ci->i_ceph_lock);
2033	if (pool == ci->i_layout.pool_id &&
2034	    pool_ns == rcu_dereference_raw(ci->i_layout.pool_ns)) {
2035		ci->i_ceph_flags |= flags;
2036        } else {
2037		pool = ci->i_layout.pool_id;
2038		flags = ci->i_ceph_flags;
2039	}
2040	spin_unlock(&ci->i_ceph_lock);
2041	goto check;
2042}
2043
2044void ceph_pool_perm_destroy(struct ceph_mds_client *mdsc)
2045{
2046	struct ceph_pool_perm *perm;
2047	struct rb_node *n;
2048
2049	while (!RB_EMPTY_ROOT(&mdsc->pool_perm_tree)) {
2050		n = rb_first(&mdsc->pool_perm_tree);
2051		perm = rb_entry(n, struct ceph_pool_perm, node);
2052		rb_erase(n, &mdsc->pool_perm_tree);
2053		kfree(perm);
2054	}
2055}