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v4.6
   1#include <linux/ceph/ceph_debug.h>
   2
   3#include <linux/module.h>
   4#include <linux/sched.h>
   5#include <linux/slab.h>
   6#include <linux/file.h>
   7#include <linux/mount.h>
   8#include <linux/namei.h>
   9#include <linux/writeback.h>
  10#include <linux/falloc.h>
  11
  12#include "super.h"
  13#include "mds_client.h"
  14#include "cache.h"
  15
  16/*
  17 * Ceph file operations
  18 *
  19 * Implement basic open/close functionality, and implement
  20 * read/write.
  21 *
  22 * We implement three modes of file I/O:
  23 *  - buffered uses the generic_file_aio_{read,write} helpers
  24 *
  25 *  - synchronous is used when there is multi-client read/write
  26 *    sharing, avoids the page cache, and synchronously waits for an
  27 *    ack from the OSD.
  28 *
  29 *  - direct io takes the variant of the sync path that references
  30 *    user pages directly.
  31 *
  32 * fsync() flushes and waits on dirty pages, but just queues metadata
  33 * for writeback: since the MDS can recover size and mtime there is no
  34 * need to wait for MDS acknowledgement.
  35 */
  36
  37/*
  38 * Calculate the length sum of direct io vectors that can
  39 * be combined into one page vector.
  40 */
  41static size_t dio_get_pagev_size(const struct iov_iter *it)
  42{
  43    const struct iovec *iov = it->iov;
  44    const struct iovec *iovend = iov + it->nr_segs;
  45    size_t size;
  46
  47    size = iov->iov_len - it->iov_offset;
  48    /*
  49     * An iov can be page vectored when both the current tail
  50     * and the next base are page aligned.
  51     */
  52    while (PAGE_ALIGNED((iov->iov_base + iov->iov_len)) &&
  53           (++iov < iovend && PAGE_ALIGNED((iov->iov_base)))) {
  54        size += iov->iov_len;
  55    }
  56    dout("dio_get_pagevlen len = %zu\n", size);
  57    return size;
  58}
  59
  60/*
  61 * Allocate a page vector based on (@it, @nbytes).
  62 * The return value is the tuple describing a page vector,
  63 * that is (@pages, @page_align, @num_pages).
  64 */
  65static struct page **
  66dio_get_pages_alloc(const struct iov_iter *it, size_t nbytes,
  67		    size_t *page_align, int *num_pages)
  68{
  69	struct iov_iter tmp_it = *it;
  70	size_t align;
  71	struct page **pages;
  72	int ret = 0, idx, npages;
  73
  74	align = (unsigned long)(it->iov->iov_base + it->iov_offset) &
  75		(PAGE_SIZE - 1);
  76	npages = calc_pages_for(align, nbytes);
  77	pages = kmalloc(sizeof(*pages) * npages, GFP_KERNEL);
  78	if (!pages) {
  79		pages = vmalloc(sizeof(*pages) * npages);
  80		if (!pages)
  81			return ERR_PTR(-ENOMEM);
  82	}
  83
  84	for (idx = 0; idx < npages; ) {
  85		size_t start;
  86		ret = iov_iter_get_pages(&tmp_it, pages + idx, nbytes,
  87					 npages - idx, &start);
  88		if (ret < 0)
  89			goto fail;
  90
  91		iov_iter_advance(&tmp_it, ret);
  92		nbytes -= ret;
  93		idx += (ret + start + PAGE_SIZE - 1) / PAGE_SIZE;
  94	}
  95
  96	BUG_ON(nbytes != 0);
  97	*num_pages = npages;
  98	*page_align = align;
  99	dout("dio_get_pages_alloc: got %d pages align %zu\n", npages, align);
 100	return pages;
 101fail:
 102	ceph_put_page_vector(pages, idx, false);
 103	return ERR_PTR(ret);
 104}
 105
 106/*
 107 * Prepare an open request.  Preallocate ceph_cap to avoid an
 108 * inopportune ENOMEM later.
 109 */
 110static struct ceph_mds_request *
 111prepare_open_request(struct super_block *sb, int flags, int create_mode)
 112{
 113	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 114	struct ceph_mds_client *mdsc = fsc->mdsc;
 115	struct ceph_mds_request *req;
 116	int want_auth = USE_ANY_MDS;
 117	int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
 118
 119	if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
 120		want_auth = USE_AUTH_MDS;
 121
 122	req = ceph_mdsc_create_request(mdsc, op, want_auth);
 123	if (IS_ERR(req))
 124		goto out;
 125	req->r_fmode = ceph_flags_to_mode(flags);
 126	req->r_args.open.flags = cpu_to_le32(flags);
 127	req->r_args.open.mode = cpu_to_le32(create_mode);
 128out:
 129	return req;
 130}
 131
 132/*
 133 * initialize private struct file data.
 134 * if we fail, clean up by dropping fmode reference on the ceph_inode
 135 */
 136static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
 137{
 138	struct ceph_file_info *cf;
 139	int ret = 0;
 140	struct ceph_inode_info *ci = ceph_inode(inode);
 141	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
 142	struct ceph_mds_client *mdsc = fsc->mdsc;
 143
 144	switch (inode->i_mode & S_IFMT) {
 145	case S_IFREG:
 146		/* First file open request creates the cookie, we want to keep
 147		 * this cookie around for the filetime of the inode as not to
 148		 * have to worry about fscache register / revoke / operation
 149		 * races.
 150		 *
 151		 * Also, if we know the operation is going to invalidate data
 152		 * (non readonly) just nuke the cache right away.
 153		 */
 154		ceph_fscache_register_inode_cookie(mdsc->fsc, ci);
 155		if ((fmode & CEPH_FILE_MODE_WR))
 156			ceph_fscache_invalidate(inode);
 157	case S_IFDIR:
 158		dout("init_file %p %p 0%o (regular)\n", inode, file,
 159		     inode->i_mode);
 160		cf = kmem_cache_zalloc(ceph_file_cachep, GFP_KERNEL);
 161		if (cf == NULL) {
 162			ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 163			return -ENOMEM;
 164		}
 165		cf->fmode = fmode;
 166		cf->next_offset = 2;
 167		cf->readdir_cache_idx = -1;
 168		file->private_data = cf;
 169		BUG_ON(inode->i_fop->release != ceph_release);
 170		break;
 171
 172	case S_IFLNK:
 173		dout("init_file %p %p 0%o (symlink)\n", inode, file,
 174		     inode->i_mode);
 175		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 176		break;
 177
 178	default:
 179		dout("init_file %p %p 0%o (special)\n", inode, file,
 180		     inode->i_mode);
 181		/*
 182		 * we need to drop the open ref now, since we don't
 183		 * have .release set to ceph_release.
 184		 */
 185		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 186		BUG_ON(inode->i_fop->release == ceph_release);
 187
 188		/* call the proper open fop */
 189		ret = inode->i_fop->open(inode, file);
 190	}
 191	return ret;
 192}
 193
 194/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 195 * If we already have the requisite capabilities, we can satisfy
 196 * the open request locally (no need to request new caps from the
 197 * MDS).  We do, however, need to inform the MDS (asynchronously)
 198 * if our wanted caps set expands.
 199 */
 200int ceph_open(struct inode *inode, struct file *file)
 201{
 202	struct ceph_inode_info *ci = ceph_inode(inode);
 203	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
 204	struct ceph_mds_client *mdsc = fsc->mdsc;
 205	struct ceph_mds_request *req;
 206	struct ceph_file_info *cf = file->private_data;
 207	int err;
 208	int flags, fmode, wanted;
 209
 210	if (cf) {
 211		dout("open file %p is already opened\n", file);
 212		return 0;
 213	}
 214
 215	/* filter out O_CREAT|O_EXCL; vfs did that already.  yuck. */
 216	flags = file->f_flags & ~(O_CREAT|O_EXCL);
 217	if (S_ISDIR(inode->i_mode))
 218		flags = O_DIRECTORY;  /* mds likes to know */
 219
 220	dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
 221	     ceph_vinop(inode), file, flags, file->f_flags);
 222	fmode = ceph_flags_to_mode(flags);
 223	wanted = ceph_caps_for_mode(fmode);
 224
 225	/* snapped files are read-only */
 226	if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
 227		return -EROFS;
 228
 229	/* trivially open snapdir */
 230	if (ceph_snap(inode) == CEPH_SNAPDIR) {
 231		spin_lock(&ci->i_ceph_lock);
 232		__ceph_get_fmode(ci, fmode);
 233		spin_unlock(&ci->i_ceph_lock);
 234		return ceph_init_file(inode, file, fmode);
 235	}
 236
 237	/*
 238	 * No need to block if we have caps on the auth MDS (for
 239	 * write) or any MDS (for read).  Update wanted set
 240	 * asynchronously.
 241	 */
 242	spin_lock(&ci->i_ceph_lock);
 243	if (__ceph_is_any_real_caps(ci) &&
 244	    (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
 245		int mds_wanted = __ceph_caps_mds_wanted(ci);
 246		int issued = __ceph_caps_issued(ci, NULL);
 247
 248		dout("open %p fmode %d want %s issued %s using existing\n",
 249		     inode, fmode, ceph_cap_string(wanted),
 250		     ceph_cap_string(issued));
 251		__ceph_get_fmode(ci, fmode);
 252		spin_unlock(&ci->i_ceph_lock);
 253
 254		/* adjust wanted? */
 255		if ((issued & wanted) != wanted &&
 256		    (mds_wanted & wanted) != wanted &&
 257		    ceph_snap(inode) != CEPH_SNAPDIR)
 258			ceph_check_caps(ci, 0, NULL);
 259
 260		return ceph_init_file(inode, file, fmode);
 261	} else if (ceph_snap(inode) != CEPH_NOSNAP &&
 262		   (ci->i_snap_caps & wanted) == wanted) {
 263		__ceph_get_fmode(ci, fmode);
 264		spin_unlock(&ci->i_ceph_lock);
 265		return ceph_init_file(inode, file, fmode);
 266	}
 267
 268	spin_unlock(&ci->i_ceph_lock);
 269
 270	dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
 271	req = prepare_open_request(inode->i_sb, flags, 0);
 272	if (IS_ERR(req)) {
 273		err = PTR_ERR(req);
 274		goto out;
 275	}
 276	req->r_inode = inode;
 277	ihold(inode);
 278
 279	req->r_num_caps = 1;
 280	err = ceph_mdsc_do_request(mdsc, NULL, req);
 281	if (!err)
 282		err = ceph_init_file(inode, file, req->r_fmode);
 283	ceph_mdsc_put_request(req);
 284	dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
 285out:
 286	return err;
 287}
 288
 289
 290/*
 291 * Do a lookup + open with a single request.  If we get a non-existent
 292 * file or symlink, return 1 so the VFS can retry.
 293 */
 294int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 295		     struct file *file, unsigned flags, umode_t mode,
 296		     int *opened)
 297{
 298	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 299	struct ceph_mds_client *mdsc = fsc->mdsc;
 300	struct ceph_mds_request *req;
 301	struct dentry *dn;
 302	struct ceph_acls_info acls = {};
 303       int mask;
 304	int err;
 305
 306	dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
 307	     dir, dentry, dentry,
 308	     d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
 309
 310	if (dentry->d_name.len > NAME_MAX)
 311		return -ENAMETOOLONG;
 312
 313	err = ceph_init_dentry(dentry);
 314	if (err < 0)
 315		return err;
 316
 317	if (flags & O_CREAT) {
 318		err = ceph_pre_init_acls(dir, &mode, &acls);
 319		if (err < 0)
 320			return err;
 321	}
 322
 323	/* do the open */
 324	req = prepare_open_request(dir->i_sb, flags, mode);
 325	if (IS_ERR(req)) {
 326		err = PTR_ERR(req);
 327		goto out_acl;
 328	}
 329	req->r_dentry = dget(dentry);
 330	req->r_num_caps = 2;
 331	if (flags & O_CREAT) {
 332		req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 333		req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 334		if (acls.pagelist) {
 335			req->r_pagelist = acls.pagelist;
 336			acls.pagelist = NULL;
 337		}
 338	}
 339
 340       mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
 341       if (ceph_security_xattr_wanted(dir))
 342               mask |= CEPH_CAP_XATTR_SHARED;
 343       req->r_args.open.mask = cpu_to_le32(mask);
 344
 345	req->r_locked_dir = dir;           /* caller holds dir->i_mutex */
 346	err = ceph_mdsc_do_request(mdsc,
 347				   (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
 348				   req);
 349	err = ceph_handle_snapdir(req, dentry, err);
 350	if (err)
 351		goto out_req;
 352
 353	if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
 354		err = ceph_handle_notrace_create(dir, dentry);
 355
 356	if (d_unhashed(dentry)) {
 357		dn = ceph_finish_lookup(req, dentry, err);
 358		if (IS_ERR(dn))
 359			err = PTR_ERR(dn);
 360	} else {
 361		/* we were given a hashed negative dentry */
 362		dn = NULL;
 363	}
 364	if (err)
 365		goto out_req;
 366	if (dn || d_really_is_negative(dentry) || d_is_symlink(dentry)) {
 367		/* make vfs retry on splice, ENOENT, or symlink */
 368		dout("atomic_open finish_no_open on dn %p\n", dn);
 369		err = finish_no_open(file, dn);
 370	} else {
 371		dout("atomic_open finish_open on dn %p\n", dn);
 372		if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
 373			ceph_init_inode_acls(d_inode(dentry), &acls);
 374			*opened |= FILE_CREATED;
 375		}
 376		err = finish_open(file, dentry, ceph_open, opened);
 377	}
 378out_req:
 379	if (!req->r_err && req->r_target_inode)
 380		ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
 381	ceph_mdsc_put_request(req);
 382out_acl:
 383	ceph_release_acls_info(&acls);
 384	dout("atomic_open result=%d\n", err);
 385	return err;
 386}
 387
 388int ceph_release(struct inode *inode, struct file *file)
 389{
 390	struct ceph_inode_info *ci = ceph_inode(inode);
 391	struct ceph_file_info *cf = file->private_data;
 392
 393	dout("release inode %p file %p\n", inode, file);
 394	ceph_put_fmode(ci, cf->fmode);
 395	if (cf->last_readdir)
 396		ceph_mdsc_put_request(cf->last_readdir);
 397	kfree(cf->last_name);
 398	kfree(cf->dir_info);
 399	kmem_cache_free(ceph_file_cachep, cf);
 400
 401	/* wake up anyone waiting for caps on this inode */
 402	wake_up_all(&ci->i_cap_wq);
 403	return 0;
 404}
 405
 406enum {
 407	HAVE_RETRIED = 1,
 408	CHECK_EOF =    2,
 409	READ_INLINE =  3,
 410};
 411
 412/*
 413 * Read a range of bytes striped over one or more objects.  Iterate over
 414 * objects we stripe over.  (That's not atomic, but good enough for now.)
 415 *
 416 * If we get a short result from the OSD, check against i_size; we need to
 417 * only return a short read to the caller if we hit EOF.
 418 */
 419static int striped_read(struct inode *inode,
 420			u64 off, u64 len,
 421			struct page **pages, int num_pages,
 422			int *checkeof)
 423{
 424	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 425	struct ceph_inode_info *ci = ceph_inode(inode);
 426	u64 pos, this_len, left;
 427	loff_t i_size;
 428	int page_align, pages_left;
 429	int read, ret;
 430	struct page **page_pos;
 431	bool hit_stripe, was_short;
 432
 433	/*
 434	 * we may need to do multiple reads.  not atomic, unfortunately.
 435	 */
 436	pos = off;
 437	left = len;
 438	page_pos = pages;
 439	pages_left = num_pages;
 440	read = 0;
 441
 442more:
 443	page_align = pos & ~PAGE_MASK;
 444	this_len = left;
 445	ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
 446				  &ci->i_layout, pos, &this_len,
 447				  ci->i_truncate_seq,
 448				  ci->i_truncate_size,
 449				  page_pos, pages_left, page_align);
 450	if (ret == -ENOENT)
 451		ret = 0;
 452	hit_stripe = this_len < left;
 453	was_short = ret >= 0 && ret < this_len;
 454	dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, left, read,
 455	     ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
 456
 457	i_size = i_size_read(inode);
 458	if (ret >= 0) {
 459		int didpages;
 460		if (was_short && (pos + ret < i_size)) {
 461			int zlen = min(this_len - ret, i_size - pos - ret);
 462			int zoff = (off & ~PAGE_MASK) + read + ret;
 463			dout(" zero gap %llu to %llu\n",
 464				pos + ret, pos + ret + zlen);
 465			ceph_zero_page_vector_range(zoff, zlen, pages);
 466			ret += zlen;
 467		}
 468
 469		didpages = (page_align + ret) >> PAGE_SHIFT;
 470		pos += ret;
 471		read = pos - off;
 472		left -= ret;
 473		page_pos += didpages;
 474		pages_left -= didpages;
 475
 476		/* hit stripe and need continue*/
 477		if (left && hit_stripe && pos < i_size)
 478			goto more;
 479	}
 480
 481	if (read > 0) {
 482		ret = read;
 483		/* did we bounce off eof? */
 484		if (pos + left > i_size)
 485			*checkeof = CHECK_EOF;
 486	}
 487
 488	dout("striped_read returns %d\n", ret);
 489	return ret;
 490}
 491
 492/*
 493 * Completely synchronous read and write methods.  Direct from __user
 494 * buffer to osd, or directly to user pages (if O_DIRECT).
 495 *
 496 * If the read spans object boundary, just do multiple reads.
 497 */
 498static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
 499				int *checkeof)
 500{
 501	struct file *file = iocb->ki_filp;
 502	struct inode *inode = file_inode(file);
 503	struct page **pages;
 504	u64 off = iocb->ki_pos;
 505	int num_pages, ret;
 506	size_t len = iov_iter_count(i);
 
 507
 508	dout("sync_read on file %p %llu~%u %s\n", file, off,
 509	     (unsigned)len,
 510	     (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
 511
 512	if (!len)
 513		return 0;
 514	/*
 515	 * flush any page cache pages in this range.  this
 516	 * will make concurrent normal and sync io slow,
 517	 * but it will at least behave sensibly when they are
 518	 * in sequence.
 519	 */
 520	ret = filemap_write_and_wait_range(inode->i_mapping, off,
 521						off + len);
 522	if (ret < 0)
 523		return ret;
 524
 525	num_pages = calc_pages_for(off, len);
 526	pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
 527	if (IS_ERR(pages))
 528		return PTR_ERR(pages);
 529	ret = striped_read(inode, off, len, pages,
 530				num_pages, checkeof);
 531	if (ret > 0) {
 532		int l, k = 0;
 533		size_t left = ret;
 534
 535		while (left) {
 536			size_t page_off = off & ~PAGE_MASK;
 537			size_t copy = min_t(size_t, left,
 538					    PAGE_SIZE - page_off);
 539			l = copy_page_to_iter(pages[k++], page_off, copy, i);
 540			off += l;
 541			left -= l;
 542			if (l < copy)
 543				break;
 544		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 545	}
 546	ceph_release_page_vector(pages, num_pages);
 547
 548	if (off > iocb->ki_pos) {
 549		ret = off - iocb->ki_pos;
 550		iocb->ki_pos = off;
 551	}
 552
 553	dout("sync_read result %d\n", ret);
 554	return ret;
 555}
 556
 557struct ceph_aio_request {
 558	struct kiocb *iocb;
 559	size_t total_len;
 560	int write;
 561	int error;
 562	struct list_head osd_reqs;
 563	unsigned num_reqs;
 564	atomic_t pending_reqs;
 565	struct timespec mtime;
 566	struct ceph_cap_flush *prealloc_cf;
 567};
 568
 569struct ceph_aio_work {
 570	struct work_struct work;
 571	struct ceph_osd_request *req;
 572};
 573
 574static void ceph_aio_retry_work(struct work_struct *work);
 575
 576static void ceph_aio_complete(struct inode *inode,
 577			      struct ceph_aio_request *aio_req)
 578{
 579	struct ceph_inode_info *ci = ceph_inode(inode);
 580	int ret;
 581
 582	if (!atomic_dec_and_test(&aio_req->pending_reqs))
 583		return;
 584
 585	ret = aio_req->error;
 586	if (!ret)
 587		ret = aio_req->total_len;
 588
 589	dout("ceph_aio_complete %p rc %d\n", inode, ret);
 590
 591	if (ret >= 0 && aio_req->write) {
 592		int dirty;
 593
 594		loff_t endoff = aio_req->iocb->ki_pos + aio_req->total_len;
 595		if (endoff > i_size_read(inode)) {
 596			if (ceph_inode_set_size(inode, endoff))
 597				ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
 598		}
 599
 600		spin_lock(&ci->i_ceph_lock);
 601		ci->i_inline_version = CEPH_INLINE_NONE;
 602		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
 603					       &aio_req->prealloc_cf);
 604		spin_unlock(&ci->i_ceph_lock);
 605		if (dirty)
 606			__mark_inode_dirty(inode, dirty);
 607
 608	}
 609
 610	ceph_put_cap_refs(ci, (aio_req->write ? CEPH_CAP_FILE_WR :
 611						CEPH_CAP_FILE_RD));
 612
 613	aio_req->iocb->ki_complete(aio_req->iocb, ret, 0);
 614
 615	ceph_free_cap_flush(aio_req->prealloc_cf);
 616	kfree(aio_req);
 617}
 618
 619static void ceph_aio_complete_req(struct ceph_osd_request *req,
 620				  struct ceph_msg *msg)
 621{
 622	int rc = req->r_result;
 623	struct inode *inode = req->r_inode;
 624	struct ceph_aio_request *aio_req = req->r_priv;
 625	struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
 626	int num_pages = calc_pages_for((u64)osd_data->alignment,
 627				       osd_data->length);
 628
 629	dout("ceph_aio_complete_req %p rc %d bytes %llu\n",
 630	     inode, rc, osd_data->length);
 631
 632	if (rc == -EOLDSNAPC) {
 633		struct ceph_aio_work *aio_work;
 634		BUG_ON(!aio_req->write);
 635
 636		aio_work = kmalloc(sizeof(*aio_work), GFP_NOFS);
 637		if (aio_work) {
 638			INIT_WORK(&aio_work->work, ceph_aio_retry_work);
 639			aio_work->req = req;
 640			queue_work(ceph_inode_to_client(inode)->wb_wq,
 641				   &aio_work->work);
 642			return;
 643		}
 644		rc = -ENOMEM;
 645	} else if (!aio_req->write) {
 646		if (rc == -ENOENT)
 647			rc = 0;
 648		if (rc >= 0 && osd_data->length > rc) {
 649			int zoff = osd_data->alignment + rc;
 650			int zlen = osd_data->length - rc;
 651			/*
 652			 * If read is satisfied by single OSD request,
 653			 * it can pass EOF. Otherwise read is within
 654			 * i_size.
 655			 */
 656			if (aio_req->num_reqs == 1) {
 657				loff_t i_size = i_size_read(inode);
 658				loff_t endoff = aio_req->iocb->ki_pos + rc;
 659				if (endoff < i_size)
 660					zlen = min_t(size_t, zlen,
 661						     i_size - endoff);
 662				aio_req->total_len = rc + zlen;
 663			}
 664
 665			if (zlen > 0)
 666				ceph_zero_page_vector_range(zoff, zlen,
 667							    osd_data->pages);
 668		}
 669	}
 670
 671	ceph_put_page_vector(osd_data->pages, num_pages, false);
 672	ceph_osdc_put_request(req);
 673
 674	if (rc < 0)
 675		cmpxchg(&aio_req->error, 0, rc);
 676
 677	ceph_aio_complete(inode, aio_req);
 678	return;
 679}
 680
 681static void ceph_aio_retry_work(struct work_struct *work)
 682{
 683	struct ceph_aio_work *aio_work =
 684		container_of(work, struct ceph_aio_work, work);
 685	struct ceph_osd_request *orig_req = aio_work->req;
 686	struct ceph_aio_request *aio_req = orig_req->r_priv;
 687	struct inode *inode = orig_req->r_inode;
 688	struct ceph_inode_info *ci = ceph_inode(inode);
 689	struct ceph_snap_context *snapc;
 690	struct ceph_osd_request *req;
 691	int ret;
 692
 693	spin_lock(&ci->i_ceph_lock);
 694	if (__ceph_have_pending_cap_snap(ci)) {
 695		struct ceph_cap_snap *capsnap =
 696			list_last_entry(&ci->i_cap_snaps,
 697					struct ceph_cap_snap,
 698					ci_item);
 699		snapc = ceph_get_snap_context(capsnap->context);
 700	} else {
 701		BUG_ON(!ci->i_head_snapc);
 702		snapc = ceph_get_snap_context(ci->i_head_snapc);
 703	}
 704	spin_unlock(&ci->i_ceph_lock);
 705
 706	req = ceph_osdc_alloc_request(orig_req->r_osdc, snapc, 2,
 707			false, GFP_NOFS);
 708	if (!req) {
 709		ret = -ENOMEM;
 710		req = orig_req;
 711		goto out;
 712	}
 713
 714	req->r_flags =	CEPH_OSD_FLAG_ORDERSNAP |
 715			CEPH_OSD_FLAG_ONDISK |
 716			CEPH_OSD_FLAG_WRITE;
 717	req->r_base_oloc = orig_req->r_base_oloc;
 718	req->r_base_oid = orig_req->r_base_oid;
 
 
 
 
 
 
 
 719
 720	req->r_ops[0] = orig_req->r_ops[0];
 721	osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC, 0);
 722
 723	ceph_osdc_build_request(req, req->r_ops[0].extent.offset,
 724				snapc, CEPH_NOSNAP, &aio_req->mtime);
 725
 726	ceph_osdc_put_request(orig_req);
 727
 728	req->r_callback = ceph_aio_complete_req;
 729	req->r_inode = inode;
 730	req->r_priv = aio_req;
 731
 732	ret = ceph_osdc_start_request(req->r_osdc, req, false);
 733out:
 734	if (ret < 0) {
 735		req->r_result = ret;
 736		ceph_aio_complete_req(req, NULL);
 737	}
 738
 739	ceph_put_snap_context(snapc);
 740	kfree(aio_work);
 741}
 742
 743/*
 744 * Write commit request unsafe callback, called to tell us when a
 745 * request is unsafe (that is, in flight--has been handed to the
 746 * messenger to send to its target osd).  It is called again when
 747 * we've received a response message indicating the request is
 748 * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
 749 * is completed early (and unsuccessfully) due to a timeout or
 750 * interrupt.
 751 *
 752 * This is used if we requested both an ACK and ONDISK commit reply
 753 * from the OSD.
 754 */
 755static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
 756{
 757	struct ceph_inode_info *ci = ceph_inode(req->r_inode);
 758
 759	dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
 760		unsafe ? "un" : "");
 761	if (unsafe) {
 762		ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
 763		spin_lock(&ci->i_unsafe_lock);
 764		list_add_tail(&req->r_unsafe_item,
 765			      &ci->i_unsafe_writes);
 766		spin_unlock(&ci->i_unsafe_lock);
 
 
 767	} else {
 768		spin_lock(&ci->i_unsafe_lock);
 769		list_del_init(&req->r_unsafe_item);
 770		spin_unlock(&ci->i_unsafe_lock);
 771		ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
 772	}
 773}
 774
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 775
 776static ssize_t
 777ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
 778		       struct ceph_snap_context *snapc,
 779		       struct ceph_cap_flush **pcf)
 780{
 781	struct file *file = iocb->ki_filp;
 782	struct inode *inode = file_inode(file);
 783	struct ceph_inode_info *ci = ceph_inode(inode);
 784	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 785	struct ceph_vino vino;
 786	struct ceph_osd_request *req;
 787	struct page **pages;
 788	struct ceph_aio_request *aio_req = NULL;
 789	int num_pages = 0;
 790	int flags;
 791	int ret;
 792	struct timespec mtime = current_fs_time(inode->i_sb);
 793	size_t count = iov_iter_count(iter);
 794	loff_t pos = iocb->ki_pos;
 795	bool write = iov_iter_rw(iter) == WRITE;
 796
 797	if (write && ceph_snap(file_inode(file)) != CEPH_NOSNAP)
 798		return -EROFS;
 799
 800	dout("sync_direct_read_write (%s) on file %p %lld~%u\n",
 801	     (write ? "write" : "read"), file, pos, (unsigned)count);
 802
 803	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
 804	if (ret < 0)
 805		return ret;
 806
 807	if (write) {
 808		ret = invalidate_inode_pages2_range(inode->i_mapping,
 809					pos >> PAGE_SHIFT,
 810					(pos + count) >> PAGE_SHIFT);
 811		if (ret < 0)
 812			dout("invalidate_inode_pages2_range returned %d\n", ret);
 813
 814		flags = CEPH_OSD_FLAG_ORDERSNAP |
 815			CEPH_OSD_FLAG_ONDISK |
 816			CEPH_OSD_FLAG_WRITE;
 817	} else {
 818		flags = CEPH_OSD_FLAG_READ;
 819	}
 820
 821	while (iov_iter_count(iter) > 0) {
 822		u64 size = dio_get_pagev_size(iter);
 823		size_t start = 0;
 824		ssize_t len;
 825
 826		vino = ceph_vino(inode);
 827		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
 828					    vino, pos, &size, 0,
 829					    /*include a 'startsync' command*/
 830					    write ? 2 : 1,
 831					    write ? CEPH_OSD_OP_WRITE :
 832						    CEPH_OSD_OP_READ,
 833					    flags, snapc,
 834					    ci->i_truncate_seq,
 835					    ci->i_truncate_size,
 836					    false);
 837		if (IS_ERR(req)) {
 838			ret = PTR_ERR(req);
 839			break;
 840		}
 841
 842		len = size;
 843		pages = dio_get_pages_alloc(iter, len, &start, &num_pages);
 844		if (IS_ERR(pages)) {
 845			ceph_osdc_put_request(req);
 846			ret = PTR_ERR(pages);
 847			break;
 848		}
 849
 850		/*
 851		 * To simplify error handling, allow AIO when IO within i_size
 852		 * or IO can be satisfied by single OSD request.
 853		 */
 854		if (pos == iocb->ki_pos && !is_sync_kiocb(iocb) &&
 855		    (len == count || pos + count <= i_size_read(inode))) {
 856			aio_req = kzalloc(sizeof(*aio_req), GFP_KERNEL);
 857			if (aio_req) {
 858				aio_req->iocb = iocb;
 859				aio_req->write = write;
 860				INIT_LIST_HEAD(&aio_req->osd_reqs);
 861				if (write) {
 862					aio_req->mtime = mtime;
 863					swap(aio_req->prealloc_cf, *pcf);
 864				}
 865			}
 866			/* ignore error */
 867		}
 868
 869		if (write) {
 870			/*
 871			 * throw out any page cache pages in this range. this
 872			 * may block.
 873			 */
 874			truncate_inode_pages_range(inode->i_mapping, pos,
 875					(pos+len) | (PAGE_SIZE - 1));
 876
 877			osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC, 0);
 
 878		}
 879
 880
 881		osd_req_op_extent_osd_data_pages(req, 0, pages, len, start,
 882						 false, false);
 883
 884		ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
 885
 886		if (aio_req) {
 887			aio_req->total_len += len;
 888			aio_req->num_reqs++;
 889			atomic_inc(&aio_req->pending_reqs);
 890
 891			req->r_callback = ceph_aio_complete_req;
 892			req->r_inode = inode;
 893			req->r_priv = aio_req;
 894			list_add_tail(&req->r_unsafe_item, &aio_req->osd_reqs);
 895
 896			pos += len;
 897			iov_iter_advance(iter, len);
 898			continue;
 899		}
 900
 901		ret = ceph_osdc_start_request(req->r_osdc, req, false);
 902		if (!ret)
 903			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
 904
 905		size = i_size_read(inode);
 906		if (!write) {
 907			if (ret == -ENOENT)
 908				ret = 0;
 909			if (ret >= 0 && ret < len && pos + ret < size) {
 910				int zlen = min_t(size_t, len - ret,
 911						 size - pos - ret);
 912				ceph_zero_page_vector_range(start + ret, zlen,
 913							    pages);
 914				ret += zlen;
 915			}
 916			if (ret >= 0)
 917				len = ret;
 918		}
 919
 920		ceph_put_page_vector(pages, num_pages, false);
 921
 922		ceph_osdc_put_request(req);
 923		if (ret < 0)
 924			break;
 925
 926		pos += len;
 927		iov_iter_advance(iter, len);
 928
 929		if (!write && pos >= size)
 930			break;
 931
 932		if (write && pos > size) {
 933			if (ceph_inode_set_size(inode, pos))
 934				ceph_check_caps(ceph_inode(inode),
 935						CHECK_CAPS_AUTHONLY,
 936						NULL);
 937		}
 938	}
 939
 940	if (aio_req) {
 
 
 941		if (aio_req->num_reqs == 0) {
 942			kfree(aio_req);
 943			return ret;
 944		}
 945
 946		ceph_get_cap_refs(ci, write ? CEPH_CAP_FILE_WR :
 947					      CEPH_CAP_FILE_RD);
 948
 949		while (!list_empty(&aio_req->osd_reqs)) {
 950			req = list_first_entry(&aio_req->osd_reqs,
 
 951					       struct ceph_osd_request,
 952					       r_unsafe_item);
 953			list_del_init(&req->r_unsafe_item);
 954			if (ret >= 0)
 955				ret = ceph_osdc_start_request(req->r_osdc,
 956							      req, false);
 957			if (ret < 0) {
 958				req->r_result = ret;
 959				ceph_aio_complete_req(req, NULL);
 960			}
 961		}
 962		return -EIOCBQUEUED;
 963	}
 964
 965	if (ret != -EOLDSNAPC && pos > iocb->ki_pos) {
 966		ret = pos - iocb->ki_pos;
 967		iocb->ki_pos = pos;
 968	}
 969	return ret;
 970}
 971
 972/*
 973 * Synchronous write, straight from __user pointer or user pages.
 974 *
 975 * If write spans object boundary, just do multiple writes.  (For a
 976 * correct atomic write, we should e.g. take write locks on all
 977 * objects, rollback on failure, etc.)
 978 */
 979static ssize_t
 980ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos,
 981		struct ceph_snap_context *snapc)
 982{
 983	struct file *file = iocb->ki_filp;
 984	struct inode *inode = file_inode(file);
 985	struct ceph_inode_info *ci = ceph_inode(inode);
 986	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 987	struct ceph_vino vino;
 988	struct ceph_osd_request *req;
 989	struct page **pages;
 990	u64 len;
 991	int num_pages;
 992	int written = 0;
 993	int flags;
 994	int check_caps = 0;
 995	int ret;
 996	struct timespec mtime = current_fs_time(inode->i_sb);
 997	size_t count = iov_iter_count(from);
 998
 999	if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
1000		return -EROFS;
1001
1002	dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
1003
1004	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
1005	if (ret < 0)
1006		return ret;
1007
1008	ret = invalidate_inode_pages2_range(inode->i_mapping,
1009					    pos >> PAGE_SHIFT,
1010					    (pos + count) >> PAGE_SHIFT);
1011	if (ret < 0)
1012		dout("invalidate_inode_pages2_range returned %d\n", ret);
1013
1014	flags = CEPH_OSD_FLAG_ORDERSNAP |
1015		CEPH_OSD_FLAG_ONDISK |
1016		CEPH_OSD_FLAG_WRITE |
1017		CEPH_OSD_FLAG_ACK;
1018
1019	while ((len = iov_iter_count(from)) > 0) {
1020		size_t left;
1021		int n;
1022
1023		vino = ceph_vino(inode);
1024		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1025					    vino, pos, &len, 0, 1,
1026					    CEPH_OSD_OP_WRITE, flags, snapc,
1027					    ci->i_truncate_seq,
1028					    ci->i_truncate_size,
1029					    false);
1030		if (IS_ERR(req)) {
1031			ret = PTR_ERR(req);
1032			break;
1033		}
1034
1035		/*
1036		 * write from beginning of first page,
1037		 * regardless of io alignment
1038		 */
1039		num_pages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
1040
1041		pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
1042		if (IS_ERR(pages)) {
1043			ret = PTR_ERR(pages);
1044			goto out;
1045		}
1046
1047		left = len;
1048		for (n = 0; n < num_pages; n++) {
1049			size_t plen = min_t(size_t, left, PAGE_SIZE);
1050			ret = copy_page_from_iter(pages[n], 0, plen, from);
1051			if (ret != plen) {
1052				ret = -EFAULT;
1053				break;
1054			}
1055			left -= ret;
1056		}
1057
1058		if (ret < 0) {
1059			ceph_release_page_vector(pages, num_pages);
1060			goto out;
1061		}
1062
1063		/* get a second commit callback */
1064		req->r_unsafe_callback = ceph_sync_write_unsafe;
1065		req->r_inode = inode;
1066
1067		osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
1068						false, true);
1069
1070		/* BUG_ON(vino.snap != CEPH_NOSNAP); */
1071		ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
1072
1073		ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1074		if (!ret)
1075			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1076
1077out:
1078		ceph_osdc_put_request(req);
1079		if (ret == 0) {
1080			pos += len;
1081			written += len;
1082
1083			if (pos > i_size_read(inode)) {
1084				check_caps = ceph_inode_set_size(inode, pos);
1085				if (check_caps)
1086					ceph_check_caps(ceph_inode(inode),
1087							CHECK_CAPS_AUTHONLY,
1088							NULL);
1089			}
1090		} else
1091			break;
1092	}
1093
1094	if (ret != -EOLDSNAPC && written > 0) {
1095		ret = written;
1096		iocb->ki_pos = pos;
1097	}
1098	return ret;
1099}
1100
1101/*
1102 * Wrap generic_file_aio_read with checks for cap bits on the inode.
1103 * Atomically grab references, so that those bits are not released
1104 * back to the MDS mid-read.
1105 *
1106 * Hmm, the sync read case isn't actually async... should it be?
1107 */
1108static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
1109{
1110	struct file *filp = iocb->ki_filp;
1111	struct ceph_file_info *fi = filp->private_data;
1112	size_t len = iov_iter_count(to);
1113	struct inode *inode = file_inode(filp);
1114	struct ceph_inode_info *ci = ceph_inode(inode);
1115	struct page *pinned_page = NULL;
1116	ssize_t ret;
1117	int want, got = 0;
1118	int retry_op = 0, read = 0;
1119
1120again:
1121	dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
1122	     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
1123
1124	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1125		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
1126	else
1127		want = CEPH_CAP_FILE_CACHE;
1128	ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page);
1129	if (ret < 0)
1130		return ret;
1131
1132	if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
1133	    (iocb->ki_flags & IOCB_DIRECT) ||
1134	    (fi->flags & CEPH_F_SYNC)) {
1135
1136		dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
1137		     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
1138		     ceph_cap_string(got));
1139
1140		if (ci->i_inline_version == CEPH_INLINE_NONE) {
1141			if (!retry_op && (iocb->ki_flags & IOCB_DIRECT)) {
1142				ret = ceph_direct_read_write(iocb, to,
1143							     NULL, NULL);
1144				if (ret >= 0 && ret < len)
1145					retry_op = CHECK_EOF;
1146			} else {
1147				ret = ceph_sync_read(iocb, to, &retry_op);
1148			}
1149		} else {
1150			retry_op = READ_INLINE;
1151		}
1152	} else {
1153		dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
1154		     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
1155		     ceph_cap_string(got));
1156
1157		ret = generic_file_read_iter(iocb, to);
 
1158	}
1159	dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
1160	     inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
1161	if (pinned_page) {
1162		put_page(pinned_page);
1163		pinned_page = NULL;
1164	}
1165	ceph_put_cap_refs(ci, got);
1166	if (retry_op > HAVE_RETRIED && ret >= 0) {
1167		int statret;
1168		struct page *page = NULL;
1169		loff_t i_size;
1170		if (retry_op == READ_INLINE) {
1171			page = __page_cache_alloc(GFP_KERNEL);
1172			if (!page)
1173				return -ENOMEM;
1174		}
1175
1176		statret = __ceph_do_getattr(inode, page,
1177					    CEPH_STAT_CAP_INLINE_DATA, !!page);
1178		if (statret < 0) {
1179			 __free_page(page);
 
1180			if (statret == -ENODATA) {
1181				BUG_ON(retry_op != READ_INLINE);
1182				goto again;
1183			}
1184			return statret;
1185		}
1186
1187		i_size = i_size_read(inode);
1188		if (retry_op == READ_INLINE) {
1189			BUG_ON(ret > 0 || read > 0);
1190			if (iocb->ki_pos < i_size &&
1191			    iocb->ki_pos < PAGE_SIZE) {
1192				loff_t end = min_t(loff_t, i_size,
1193						   iocb->ki_pos + len);
1194				end = min_t(loff_t, end, PAGE_SIZE);
1195				if (statret < end)
1196					zero_user_segment(page, statret, end);
1197				ret = copy_page_to_iter(page,
1198						iocb->ki_pos & ~PAGE_MASK,
1199						end - iocb->ki_pos, to);
1200				iocb->ki_pos += ret;
1201				read += ret;
1202			}
1203			if (iocb->ki_pos < i_size && read < len) {
1204				size_t zlen = min_t(size_t, len - read,
1205						    i_size - iocb->ki_pos);
1206				ret = iov_iter_zero(zlen, to);
1207				iocb->ki_pos += ret;
1208				read += ret;
1209			}
1210			__free_pages(page, 0);
1211			return read;
1212		}
1213
1214		/* hit EOF or hole? */
1215		if (retry_op == CHECK_EOF && iocb->ki_pos < i_size &&
1216		    ret < len) {
1217			dout("sync_read hit hole, ppos %lld < size %lld"
1218			     ", reading more\n", iocb->ki_pos, i_size);
1219
1220			read += ret;
1221			len -= ret;
1222			retry_op = HAVE_RETRIED;
1223			goto again;
1224		}
1225	}
1226
1227	if (ret >= 0)
1228		ret += read;
1229
1230	return ret;
1231}
1232
1233/*
1234 * Take cap references to avoid releasing caps to MDS mid-write.
1235 *
1236 * If we are synchronous, and write with an old snap context, the OSD
1237 * may return EOLDSNAPC.  In that case, retry the write.. _after_
1238 * dropping our cap refs and allowing the pending snap to logically
1239 * complete _before_ this write occurs.
1240 *
1241 * If we are near ENOSPC, write synchronously.
1242 */
1243static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
1244{
1245	struct file *file = iocb->ki_filp;
1246	struct ceph_file_info *fi = file->private_data;
1247	struct inode *inode = file_inode(file);
1248	struct ceph_inode_info *ci = ceph_inode(inode);
1249	struct ceph_osd_client *osdc =
1250		&ceph_sb_to_client(inode->i_sb)->client->osdc;
1251	struct ceph_cap_flush *prealloc_cf;
1252	ssize_t count, written = 0;
1253	int err, want, got;
1254	loff_t pos;
1255
1256	if (ceph_snap(inode) != CEPH_NOSNAP)
1257		return -EROFS;
1258
1259	prealloc_cf = ceph_alloc_cap_flush();
1260	if (!prealloc_cf)
1261		return -ENOMEM;
1262
1263	inode_lock(inode);
1264
1265	/* We can write back this queue in page reclaim */
1266	current->backing_dev_info = inode_to_bdi(inode);
1267
1268	if (iocb->ki_flags & IOCB_APPEND) {
1269		err = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1270		if (err < 0)
1271			goto out;
1272	}
1273
1274	err = generic_write_checks(iocb, from);
1275	if (err <= 0)
1276		goto out;
1277
1278	pos = iocb->ki_pos;
1279	count = iov_iter_count(from);
1280	err = file_remove_privs(file);
1281	if (err)
1282		goto out;
1283
1284	err = file_update_time(file);
1285	if (err)
1286		goto out;
1287
1288	if (ci->i_inline_version != CEPH_INLINE_NONE) {
1289		err = ceph_uninline_data(file, NULL);
1290		if (err < 0)
1291			goto out;
1292	}
1293
1294retry_snap:
1295	if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
1296		err = -ENOSPC;
1297		goto out;
1298	}
1299
1300	dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
1301	     inode, ceph_vinop(inode), pos, count, i_size_read(inode));
1302	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1303		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1304	else
1305		want = CEPH_CAP_FILE_BUFFER;
1306	got = 0;
1307	err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, pos + count,
1308			    &got, NULL);
1309	if (err < 0)
1310		goto out;
1311
1312	dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
1313	     inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
1314
1315	if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
1316	    (iocb->ki_flags & IOCB_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
1317		struct ceph_snap_context *snapc;
1318		struct iov_iter data;
1319		inode_unlock(inode);
1320
1321		spin_lock(&ci->i_ceph_lock);
1322		if (__ceph_have_pending_cap_snap(ci)) {
1323			struct ceph_cap_snap *capsnap =
1324					list_last_entry(&ci->i_cap_snaps,
1325							struct ceph_cap_snap,
1326							ci_item);
1327			snapc = ceph_get_snap_context(capsnap->context);
1328		} else {
1329			BUG_ON(!ci->i_head_snapc);
1330			snapc = ceph_get_snap_context(ci->i_head_snapc);
1331		}
1332		spin_unlock(&ci->i_ceph_lock);
1333
1334		/* we might need to revert back to that point */
1335		data = *from;
1336		if (iocb->ki_flags & IOCB_DIRECT)
1337			written = ceph_direct_read_write(iocb, &data, snapc,
1338							 &prealloc_cf);
1339		else
1340			written = ceph_sync_write(iocb, &data, pos, snapc);
1341		if (written == -EOLDSNAPC) {
1342			dout("aio_write %p %llx.%llx %llu~%u"
1343				"got EOLDSNAPC, retrying\n",
1344				inode, ceph_vinop(inode),
1345				pos, (unsigned)count);
1346			inode_lock(inode);
1347			goto retry_snap;
1348		}
1349		if (written > 0)
1350			iov_iter_advance(from, written);
1351		ceph_put_snap_context(snapc);
1352	} else {
1353		loff_t old_size = i_size_read(inode);
1354		/*
1355		 * No need to acquire the i_truncate_mutex. Because
1356		 * the MDS revokes Fwb caps before sending truncate
1357		 * message to us. We can't get Fwb cap while there
1358		 * are pending vmtruncate. So write and vmtruncate
1359		 * can not run at the same time
1360		 */
1361		written = generic_perform_write(file, from, pos);
1362		if (likely(written >= 0))
1363			iocb->ki_pos = pos + written;
1364		if (i_size_read(inode) > old_size)
1365			ceph_fscache_update_objectsize(inode);
1366		inode_unlock(inode);
1367	}
1368
1369	if (written >= 0) {
1370		int dirty;
1371		spin_lock(&ci->i_ceph_lock);
1372		ci->i_inline_version = CEPH_INLINE_NONE;
1373		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1374					       &prealloc_cf);
1375		spin_unlock(&ci->i_ceph_lock);
1376		if (dirty)
1377			__mark_inode_dirty(inode, dirty);
1378	}
1379
1380	dout("aio_write %p %llx.%llx %llu~%u  dropping cap refs on %s\n",
1381	     inode, ceph_vinop(inode), pos, (unsigned)count,
1382	     ceph_cap_string(got));
1383	ceph_put_cap_refs(ci, got);
1384
1385	if (written >= 0 &&
1386	    ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
1387	     ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
1388		err = vfs_fsync_range(file, pos, pos + written - 1, 1);
1389		if (err < 0)
1390			written = err;
1391	}
1392
1393	goto out_unlocked;
1394
1395out:
1396	inode_unlock(inode);
1397out_unlocked:
1398	ceph_free_cap_flush(prealloc_cf);
1399	current->backing_dev_info = NULL;
1400	return written ? written : err;
1401}
1402
1403/*
1404 * llseek.  be sure to verify file size on SEEK_END.
1405 */
1406static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
1407{
1408	struct inode *inode = file->f_mapping->host;
1409	loff_t i_size;
1410	int ret;
1411
1412	inode_lock(inode);
1413
1414	if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
1415		ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1416		if (ret < 0) {
1417			offset = ret;
1418			goto out;
1419		}
1420	}
1421
1422	i_size = i_size_read(inode);
1423	switch (whence) {
1424	case SEEK_END:
1425		offset += i_size;
1426		break;
1427	case SEEK_CUR:
1428		/*
1429		 * Here we special-case the lseek(fd, 0, SEEK_CUR)
1430		 * position-querying operation.  Avoid rewriting the "same"
1431		 * f_pos value back to the file because a concurrent read(),
1432		 * write() or lseek() might have altered it
1433		 */
1434		if (offset == 0) {
1435			offset = file->f_pos;
1436			goto out;
1437		}
1438		offset += file->f_pos;
1439		break;
1440	case SEEK_DATA:
1441		if (offset >= i_size) {
1442			ret = -ENXIO;
1443			goto out;
1444		}
1445		break;
1446	case SEEK_HOLE:
1447		if (offset >= i_size) {
1448			ret = -ENXIO;
1449			goto out;
1450		}
1451		offset = i_size;
1452		break;
1453	}
1454
1455	offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1456
1457out:
1458	inode_unlock(inode);
1459	return offset;
1460}
1461
1462static inline void ceph_zero_partial_page(
1463	struct inode *inode, loff_t offset, unsigned size)
1464{
1465	struct page *page;
1466	pgoff_t index = offset >> PAGE_SHIFT;
1467
1468	page = find_lock_page(inode->i_mapping, index);
1469	if (page) {
1470		wait_on_page_writeback(page);
1471		zero_user(page, offset & (PAGE_SIZE - 1), size);
1472		unlock_page(page);
1473		put_page(page);
1474	}
1475}
1476
1477static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1478				      loff_t length)
1479{
1480	loff_t nearly = round_up(offset, PAGE_SIZE);
1481	if (offset < nearly) {
1482		loff_t size = nearly - offset;
1483		if (length < size)
1484			size = length;
1485		ceph_zero_partial_page(inode, offset, size);
1486		offset += size;
1487		length -= size;
1488	}
1489	if (length >= PAGE_SIZE) {
1490		loff_t size = round_down(length, PAGE_SIZE);
1491		truncate_pagecache_range(inode, offset, offset + size - 1);
1492		offset += size;
1493		length -= size;
1494	}
1495	if (length)
1496		ceph_zero_partial_page(inode, offset, length);
1497}
1498
1499static int ceph_zero_partial_object(struct inode *inode,
1500				    loff_t offset, loff_t *length)
1501{
1502	struct ceph_inode_info *ci = ceph_inode(inode);
1503	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1504	struct ceph_osd_request *req;
1505	int ret = 0;
1506	loff_t zero = 0;
1507	int op;
1508
1509	if (!length) {
1510		op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1511		length = &zero;
1512	} else {
1513		op = CEPH_OSD_OP_ZERO;
1514	}
1515
1516	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1517					ceph_vino(inode),
1518					offset, length,
1519					0, 1, op,
1520					CEPH_OSD_FLAG_WRITE |
1521					CEPH_OSD_FLAG_ONDISK,
1522					NULL, 0, 0, false);
1523	if (IS_ERR(req)) {
1524		ret = PTR_ERR(req);
1525		goto out;
1526	}
1527
1528	ceph_osdc_build_request(req, offset, NULL, ceph_vino(inode).snap,
1529				&inode->i_mtime);
1530
1531	ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1532	if (!ret) {
1533		ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1534		if (ret == -ENOENT)
1535			ret = 0;
1536	}
1537	ceph_osdc_put_request(req);
1538
1539out:
1540	return ret;
1541}
1542
1543static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1544{
1545	int ret = 0;
1546	struct ceph_inode_info *ci = ceph_inode(inode);
1547	s32 stripe_unit = ceph_file_layout_su(ci->i_layout);
1548	s32 stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
1549	s32 object_size = ceph_file_layout_object_size(ci->i_layout);
1550	u64 object_set_size = object_size * stripe_count;
1551	u64 nearly, t;
1552
1553	/* round offset up to next period boundary */
1554	nearly = offset + object_set_size - 1;
1555	t = nearly;
1556	nearly -= do_div(t, object_set_size);
1557
1558	while (length && offset < nearly) {
1559		loff_t size = length;
1560		ret = ceph_zero_partial_object(inode, offset, &size);
1561		if (ret < 0)
1562			return ret;
1563		offset += size;
1564		length -= size;
1565	}
1566	while (length >= object_set_size) {
1567		int i;
1568		loff_t pos = offset;
1569		for (i = 0; i < stripe_count; ++i) {
1570			ret = ceph_zero_partial_object(inode, pos, NULL);
1571			if (ret < 0)
1572				return ret;
1573			pos += stripe_unit;
1574		}
1575		offset += object_set_size;
1576		length -= object_set_size;
1577	}
1578	while (length) {
1579		loff_t size = length;
1580		ret = ceph_zero_partial_object(inode, offset, &size);
1581		if (ret < 0)
1582			return ret;
1583		offset += size;
1584		length -= size;
1585	}
1586	return ret;
1587}
1588
1589static long ceph_fallocate(struct file *file, int mode,
1590				loff_t offset, loff_t length)
1591{
1592	struct ceph_file_info *fi = file->private_data;
1593	struct inode *inode = file_inode(file);
1594	struct ceph_inode_info *ci = ceph_inode(inode);
1595	struct ceph_osd_client *osdc =
1596		&ceph_inode_to_client(inode)->client->osdc;
1597	struct ceph_cap_flush *prealloc_cf;
1598	int want, got = 0;
1599	int dirty;
1600	int ret = 0;
1601	loff_t endoff = 0;
1602	loff_t size;
1603
1604	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
1605		return -EOPNOTSUPP;
1606
1607	if (!S_ISREG(inode->i_mode))
1608		return -EOPNOTSUPP;
1609
1610	prealloc_cf = ceph_alloc_cap_flush();
1611	if (!prealloc_cf)
1612		return -ENOMEM;
1613
1614	inode_lock(inode);
1615
1616	if (ceph_snap(inode) != CEPH_NOSNAP) {
1617		ret = -EROFS;
1618		goto unlock;
1619	}
1620
1621	if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) &&
1622		!(mode & FALLOC_FL_PUNCH_HOLE)) {
1623		ret = -ENOSPC;
1624		goto unlock;
1625	}
1626
1627	if (ci->i_inline_version != CEPH_INLINE_NONE) {
1628		ret = ceph_uninline_data(file, NULL);
1629		if (ret < 0)
1630			goto unlock;
1631	}
1632
1633	size = i_size_read(inode);
1634	if (!(mode & FALLOC_FL_KEEP_SIZE))
1635		endoff = offset + length;
1636
1637	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1638		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1639	else
1640		want = CEPH_CAP_FILE_BUFFER;
1641
1642	ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, endoff, &got, NULL);
1643	if (ret < 0)
1644		goto unlock;
1645
1646	if (mode & FALLOC_FL_PUNCH_HOLE) {
1647		if (offset < size)
1648			ceph_zero_pagecache_range(inode, offset, length);
1649		ret = ceph_zero_objects(inode, offset, length);
1650	} else if (endoff > size) {
1651		truncate_pagecache_range(inode, size, -1);
1652		if (ceph_inode_set_size(inode, endoff))
1653			ceph_check_caps(ceph_inode(inode),
1654				CHECK_CAPS_AUTHONLY, NULL);
1655	}
1656
1657	if (!ret) {
1658		spin_lock(&ci->i_ceph_lock);
1659		ci->i_inline_version = CEPH_INLINE_NONE;
1660		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1661					       &prealloc_cf);
1662		spin_unlock(&ci->i_ceph_lock);
1663		if (dirty)
1664			__mark_inode_dirty(inode, dirty);
1665	}
1666
1667	ceph_put_cap_refs(ci, got);
1668unlock:
1669	inode_unlock(inode);
1670	ceph_free_cap_flush(prealloc_cf);
1671	return ret;
1672}
1673
1674const struct file_operations ceph_file_fops = {
1675	.open = ceph_open,
1676	.release = ceph_release,
1677	.llseek = ceph_llseek,
1678	.read_iter = ceph_read_iter,
1679	.write_iter = ceph_write_iter,
1680	.mmap = ceph_mmap,
1681	.fsync = ceph_fsync,
1682	.lock = ceph_lock,
1683	.flock = ceph_flock,
1684	.splice_read = generic_file_splice_read,
1685	.splice_write = iter_file_splice_write,
1686	.unlocked_ioctl = ceph_ioctl,
1687	.compat_ioctl	= ceph_ioctl,
1688	.fallocate	= ceph_fallocate,
1689};
1690
v4.10.11
   1#include <linux/ceph/ceph_debug.h>
   2
   3#include <linux/module.h>
   4#include <linux/sched.h>
   5#include <linux/slab.h>
   6#include <linux/file.h>
   7#include <linux/mount.h>
   8#include <linux/namei.h>
   9#include <linux/writeback.h>
  10#include <linux/falloc.h>
  11
  12#include "super.h"
  13#include "mds_client.h"
  14#include "cache.h"
  15
  16/*
  17 * Ceph file operations
  18 *
  19 * Implement basic open/close functionality, and implement
  20 * read/write.
  21 *
  22 * We implement three modes of file I/O:
  23 *  - buffered uses the generic_file_aio_{read,write} helpers
  24 *
  25 *  - synchronous is used when there is multi-client read/write
  26 *    sharing, avoids the page cache, and synchronously waits for an
  27 *    ack from the OSD.
  28 *
  29 *  - direct io takes the variant of the sync path that references
  30 *    user pages directly.
  31 *
  32 * fsync() flushes and waits on dirty pages, but just queues metadata
  33 * for writeback: since the MDS can recover size and mtime there is no
  34 * need to wait for MDS acknowledgement.
  35 */
  36
  37/*
  38 * Calculate the length sum of direct io vectors that can
  39 * be combined into one page vector.
  40 */
  41static size_t dio_get_pagev_size(const struct iov_iter *it)
  42{
  43    const struct iovec *iov = it->iov;
  44    const struct iovec *iovend = iov + it->nr_segs;
  45    size_t size;
  46
  47    size = iov->iov_len - it->iov_offset;
  48    /*
  49     * An iov can be page vectored when both the current tail
  50     * and the next base are page aligned.
  51     */
  52    while (PAGE_ALIGNED((iov->iov_base + iov->iov_len)) &&
  53           (++iov < iovend && PAGE_ALIGNED((iov->iov_base)))) {
  54        size += iov->iov_len;
  55    }
  56    dout("dio_get_pagevlen len = %zu\n", size);
  57    return size;
  58}
  59
  60/*
  61 * Allocate a page vector based on (@it, @nbytes).
  62 * The return value is the tuple describing a page vector,
  63 * that is (@pages, @page_align, @num_pages).
  64 */
  65static struct page **
  66dio_get_pages_alloc(const struct iov_iter *it, size_t nbytes,
  67		    size_t *page_align, int *num_pages)
  68{
  69	struct iov_iter tmp_it = *it;
  70	size_t align;
  71	struct page **pages;
  72	int ret = 0, idx, npages;
  73
  74	align = (unsigned long)(it->iov->iov_base + it->iov_offset) &
  75		(PAGE_SIZE - 1);
  76	npages = calc_pages_for(align, nbytes);
  77	pages = kmalloc(sizeof(*pages) * npages, GFP_KERNEL);
  78	if (!pages) {
  79		pages = vmalloc(sizeof(*pages) * npages);
  80		if (!pages)
  81			return ERR_PTR(-ENOMEM);
  82	}
  83
  84	for (idx = 0; idx < npages; ) {
  85		size_t start;
  86		ret = iov_iter_get_pages(&tmp_it, pages + idx, nbytes,
  87					 npages - idx, &start);
  88		if (ret < 0)
  89			goto fail;
  90
  91		iov_iter_advance(&tmp_it, ret);
  92		nbytes -= ret;
  93		idx += (ret + start + PAGE_SIZE - 1) / PAGE_SIZE;
  94	}
  95
  96	BUG_ON(nbytes != 0);
  97	*num_pages = npages;
  98	*page_align = align;
  99	dout("dio_get_pages_alloc: got %d pages align %zu\n", npages, align);
 100	return pages;
 101fail:
 102	ceph_put_page_vector(pages, idx, false);
 103	return ERR_PTR(ret);
 104}
 105
 106/*
 107 * Prepare an open request.  Preallocate ceph_cap to avoid an
 108 * inopportune ENOMEM later.
 109 */
 110static struct ceph_mds_request *
 111prepare_open_request(struct super_block *sb, int flags, int create_mode)
 112{
 113	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 114	struct ceph_mds_client *mdsc = fsc->mdsc;
 115	struct ceph_mds_request *req;
 116	int want_auth = USE_ANY_MDS;
 117	int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
 118
 119	if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
 120		want_auth = USE_AUTH_MDS;
 121
 122	req = ceph_mdsc_create_request(mdsc, op, want_auth);
 123	if (IS_ERR(req))
 124		goto out;
 125	req->r_fmode = ceph_flags_to_mode(flags);
 126	req->r_args.open.flags = cpu_to_le32(flags);
 127	req->r_args.open.mode = cpu_to_le32(create_mode);
 128out:
 129	return req;
 130}
 131
 132/*
 133 * initialize private struct file data.
 134 * if we fail, clean up by dropping fmode reference on the ceph_inode
 135 */
 136static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
 137{
 138	struct ceph_file_info *cf;
 139	int ret = 0;
 
 
 
 140
 141	switch (inode->i_mode & S_IFMT) {
 142	case S_IFREG:
 143		ceph_fscache_register_inode_cookie(inode);
 144		ceph_fscache_file_set_cookie(inode, file);
 
 
 
 
 
 
 
 
 
 145	case S_IFDIR:
 146		dout("init_file %p %p 0%o (regular)\n", inode, file,
 147		     inode->i_mode);
 148		cf = kmem_cache_zalloc(ceph_file_cachep, GFP_KERNEL);
 149		if (cf == NULL) {
 150			ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 151			return -ENOMEM;
 152		}
 153		cf->fmode = fmode;
 154		cf->next_offset = 2;
 155		cf->readdir_cache_idx = -1;
 156		file->private_data = cf;
 157		BUG_ON(inode->i_fop->release != ceph_release);
 158		break;
 159
 160	case S_IFLNK:
 161		dout("init_file %p %p 0%o (symlink)\n", inode, file,
 162		     inode->i_mode);
 163		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 164		break;
 165
 166	default:
 167		dout("init_file %p %p 0%o (special)\n", inode, file,
 168		     inode->i_mode);
 169		/*
 170		 * we need to drop the open ref now, since we don't
 171		 * have .release set to ceph_release.
 172		 */
 173		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 174		BUG_ON(inode->i_fop->release == ceph_release);
 175
 176		/* call the proper open fop */
 177		ret = inode->i_fop->open(inode, file);
 178	}
 179	return ret;
 180}
 181
 182/*
 183 * try renew caps after session gets killed.
 184 */
 185int ceph_renew_caps(struct inode *inode)
 186{
 187	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
 188	struct ceph_inode_info *ci = ceph_inode(inode);
 189	struct ceph_mds_request *req;
 190	int err, flags, wanted;
 191
 192	spin_lock(&ci->i_ceph_lock);
 193	wanted = __ceph_caps_file_wanted(ci);
 194	if (__ceph_is_any_real_caps(ci) &&
 195	    (!(wanted & CEPH_CAP_ANY_WR) == 0 || ci->i_auth_cap)) {
 196		int issued = __ceph_caps_issued(ci, NULL);
 197		spin_unlock(&ci->i_ceph_lock);
 198		dout("renew caps %p want %s issued %s updating mds_wanted\n",
 199		     inode, ceph_cap_string(wanted), ceph_cap_string(issued));
 200		ceph_check_caps(ci, 0, NULL);
 201		return 0;
 202	}
 203	spin_unlock(&ci->i_ceph_lock);
 204
 205	flags = 0;
 206	if ((wanted & CEPH_CAP_FILE_RD) && (wanted & CEPH_CAP_FILE_WR))
 207		flags = O_RDWR;
 208	else if (wanted & CEPH_CAP_FILE_RD)
 209		flags = O_RDONLY;
 210	else if (wanted & CEPH_CAP_FILE_WR)
 211		flags = O_WRONLY;
 212#ifdef O_LAZY
 213	if (wanted & CEPH_CAP_FILE_LAZYIO)
 214		flags |= O_LAZY;
 215#endif
 216
 217	req = prepare_open_request(inode->i_sb, flags, 0);
 218	if (IS_ERR(req)) {
 219		err = PTR_ERR(req);
 220		goto out;
 221	}
 222
 223	req->r_inode = inode;
 224	ihold(inode);
 225	req->r_num_caps = 1;
 226	req->r_fmode = -1;
 227
 228	err = ceph_mdsc_do_request(mdsc, NULL, req);
 229	ceph_mdsc_put_request(req);
 230out:
 231	dout("renew caps %p open result=%d\n", inode, err);
 232	return err < 0 ? err : 0;
 233}
 234
 235/*
 236 * If we already have the requisite capabilities, we can satisfy
 237 * the open request locally (no need to request new caps from the
 238 * MDS).  We do, however, need to inform the MDS (asynchronously)
 239 * if our wanted caps set expands.
 240 */
 241int ceph_open(struct inode *inode, struct file *file)
 242{
 243	struct ceph_inode_info *ci = ceph_inode(inode);
 244	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
 245	struct ceph_mds_client *mdsc = fsc->mdsc;
 246	struct ceph_mds_request *req;
 247	struct ceph_file_info *cf = file->private_data;
 248	int err;
 249	int flags, fmode, wanted;
 250
 251	if (cf) {
 252		dout("open file %p is already opened\n", file);
 253		return 0;
 254	}
 255
 256	/* filter out O_CREAT|O_EXCL; vfs did that already.  yuck. */
 257	flags = file->f_flags & ~(O_CREAT|O_EXCL);
 258	if (S_ISDIR(inode->i_mode))
 259		flags = O_DIRECTORY;  /* mds likes to know */
 260
 261	dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
 262	     ceph_vinop(inode), file, flags, file->f_flags);
 263	fmode = ceph_flags_to_mode(flags);
 264	wanted = ceph_caps_for_mode(fmode);
 265
 266	/* snapped files are read-only */
 267	if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
 268		return -EROFS;
 269
 270	/* trivially open snapdir */
 271	if (ceph_snap(inode) == CEPH_SNAPDIR) {
 272		spin_lock(&ci->i_ceph_lock);
 273		__ceph_get_fmode(ci, fmode);
 274		spin_unlock(&ci->i_ceph_lock);
 275		return ceph_init_file(inode, file, fmode);
 276	}
 277
 278	/*
 279	 * No need to block if we have caps on the auth MDS (for
 280	 * write) or any MDS (for read).  Update wanted set
 281	 * asynchronously.
 282	 */
 283	spin_lock(&ci->i_ceph_lock);
 284	if (__ceph_is_any_real_caps(ci) &&
 285	    (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
 286		int mds_wanted = __ceph_caps_mds_wanted(ci);
 287		int issued = __ceph_caps_issued(ci, NULL);
 288
 289		dout("open %p fmode %d want %s issued %s using existing\n",
 290		     inode, fmode, ceph_cap_string(wanted),
 291		     ceph_cap_string(issued));
 292		__ceph_get_fmode(ci, fmode);
 293		spin_unlock(&ci->i_ceph_lock);
 294
 295		/* adjust wanted? */
 296		if ((issued & wanted) != wanted &&
 297		    (mds_wanted & wanted) != wanted &&
 298		    ceph_snap(inode) != CEPH_SNAPDIR)
 299			ceph_check_caps(ci, 0, NULL);
 300
 301		return ceph_init_file(inode, file, fmode);
 302	} else if (ceph_snap(inode) != CEPH_NOSNAP &&
 303		   (ci->i_snap_caps & wanted) == wanted) {
 304		__ceph_get_fmode(ci, fmode);
 305		spin_unlock(&ci->i_ceph_lock);
 306		return ceph_init_file(inode, file, fmode);
 307	}
 308
 309	spin_unlock(&ci->i_ceph_lock);
 310
 311	dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
 312	req = prepare_open_request(inode->i_sb, flags, 0);
 313	if (IS_ERR(req)) {
 314		err = PTR_ERR(req);
 315		goto out;
 316	}
 317	req->r_inode = inode;
 318	ihold(inode);
 319
 320	req->r_num_caps = 1;
 321	err = ceph_mdsc_do_request(mdsc, NULL, req);
 322	if (!err)
 323		err = ceph_init_file(inode, file, req->r_fmode);
 324	ceph_mdsc_put_request(req);
 325	dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
 326out:
 327	return err;
 328}
 329
 330
 331/*
 332 * Do a lookup + open with a single request.  If we get a non-existent
 333 * file or symlink, return 1 so the VFS can retry.
 334 */
 335int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 336		     struct file *file, unsigned flags, umode_t mode,
 337		     int *opened)
 338{
 339	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 340	struct ceph_mds_client *mdsc = fsc->mdsc;
 341	struct ceph_mds_request *req;
 342	struct dentry *dn;
 343	struct ceph_acls_info acls = {};
 344       int mask;
 345	int err;
 346
 347	dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
 348	     dir, dentry, dentry,
 349	     d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
 350
 351	if (dentry->d_name.len > NAME_MAX)
 352		return -ENAMETOOLONG;
 353
 
 
 
 
 354	if (flags & O_CREAT) {
 355		err = ceph_pre_init_acls(dir, &mode, &acls);
 356		if (err < 0)
 357			return err;
 358	}
 359
 360	/* do the open */
 361	req = prepare_open_request(dir->i_sb, flags, mode);
 362	if (IS_ERR(req)) {
 363		err = PTR_ERR(req);
 364		goto out_acl;
 365	}
 366	req->r_dentry = dget(dentry);
 367	req->r_num_caps = 2;
 368	if (flags & O_CREAT) {
 369		req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 370		req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 371		if (acls.pagelist) {
 372			req->r_pagelist = acls.pagelist;
 373			acls.pagelist = NULL;
 374		}
 375	}
 376
 377       mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
 378       if (ceph_security_xattr_wanted(dir))
 379               mask |= CEPH_CAP_XATTR_SHARED;
 380       req->r_args.open.mask = cpu_to_le32(mask);
 381
 382	req->r_locked_dir = dir;           /* caller holds dir->i_mutex */
 383	err = ceph_mdsc_do_request(mdsc,
 384				   (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
 385				   req);
 386	err = ceph_handle_snapdir(req, dentry, err);
 387	if (err)
 388		goto out_req;
 389
 390	if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
 391		err = ceph_handle_notrace_create(dir, dentry);
 392
 393	if (d_in_lookup(dentry)) {
 394		dn = ceph_finish_lookup(req, dentry, err);
 395		if (IS_ERR(dn))
 396			err = PTR_ERR(dn);
 397	} else {
 398		/* we were given a hashed negative dentry */
 399		dn = NULL;
 400	}
 401	if (err)
 402		goto out_req;
 403	if (dn || d_really_is_negative(dentry) || d_is_symlink(dentry)) {
 404		/* make vfs retry on splice, ENOENT, or symlink */
 405		dout("atomic_open finish_no_open on dn %p\n", dn);
 406		err = finish_no_open(file, dn);
 407	} else {
 408		dout("atomic_open finish_open on dn %p\n", dn);
 409		if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
 410			ceph_init_inode_acls(d_inode(dentry), &acls);
 411			*opened |= FILE_CREATED;
 412		}
 413		err = finish_open(file, dentry, ceph_open, opened);
 414	}
 415out_req:
 416	if (!req->r_err && req->r_target_inode)
 417		ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
 418	ceph_mdsc_put_request(req);
 419out_acl:
 420	ceph_release_acls_info(&acls);
 421	dout("atomic_open result=%d\n", err);
 422	return err;
 423}
 424
 425int ceph_release(struct inode *inode, struct file *file)
 426{
 427	struct ceph_inode_info *ci = ceph_inode(inode);
 428	struct ceph_file_info *cf = file->private_data;
 429
 430	dout("release inode %p file %p\n", inode, file);
 431	ceph_put_fmode(ci, cf->fmode);
 432	if (cf->last_readdir)
 433		ceph_mdsc_put_request(cf->last_readdir);
 434	kfree(cf->last_name);
 435	kfree(cf->dir_info);
 436	kmem_cache_free(ceph_file_cachep, cf);
 437
 438	/* wake up anyone waiting for caps on this inode */
 439	wake_up_all(&ci->i_cap_wq);
 440	return 0;
 441}
 442
 443enum {
 444	HAVE_RETRIED = 1,
 445	CHECK_EOF =    2,
 446	READ_INLINE =  3,
 447};
 448
 449/*
 450 * Read a range of bytes striped over one or more objects.  Iterate over
 451 * objects we stripe over.  (That's not atomic, but good enough for now.)
 452 *
 453 * If we get a short result from the OSD, check against i_size; we need to
 454 * only return a short read to the caller if we hit EOF.
 455 */
 456static int striped_read(struct inode *inode,
 457			u64 pos, u64 len,
 458			struct page **pages, int num_pages,
 459			int page_align, int *checkeof)
 460{
 461	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 462	struct ceph_inode_info *ci = ceph_inode(inode);
 463	u64 this_len;
 464	loff_t i_size;
 465	int page_idx;
 466	int ret, read = 0;
 
 467	bool hit_stripe, was_short;
 468
 469	/*
 470	 * we may need to do multiple reads.  not atomic, unfortunately.
 471	 */
 
 
 
 
 
 
 472more:
 473	this_len = len;
 474	page_idx = (page_align + read) >> PAGE_SHIFT;
 475	ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
 476				  &ci->i_layout, pos, &this_len,
 477				  ci->i_truncate_seq, ci->i_truncate_size,
 478				  pages + page_idx, num_pages - page_idx,
 479				  ((page_align + read) & ~PAGE_MASK));
 480	if (ret == -ENOENT)
 481		ret = 0;
 482	hit_stripe = this_len < len;
 483	was_short = ret >= 0 && ret < this_len;
 484	dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, len, read,
 485	     ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
 486
 487	i_size = i_size_read(inode);
 488	if (ret >= 0) {
 
 489		if (was_short && (pos + ret < i_size)) {
 490			int zlen = min(this_len - ret, i_size - pos - ret);
 491			int zoff = page_align + read + ret;
 492			dout(" zero gap %llu to %llu\n",
 493			     pos + ret, pos + ret + zlen);
 494			ceph_zero_page_vector_range(zoff, zlen, pages);
 495			ret += zlen;
 496		}
 497
 498		read += ret;
 499		pos += ret;
 500		len -= ret;
 
 
 
 501
 502		/* hit stripe and need continue*/
 503		if (len && hit_stripe && pos < i_size)
 504			goto more;
 505	}
 506
 507	if (read > 0) {
 508		ret = read;
 509		/* did we bounce off eof? */
 510		if (pos + len > i_size)
 511			*checkeof = CHECK_EOF;
 512	}
 513
 514	dout("striped_read returns %d\n", ret);
 515	return ret;
 516}
 517
 518/*
 519 * Completely synchronous read and write methods.  Direct from __user
 520 * buffer to osd, or directly to user pages (if O_DIRECT).
 521 *
 522 * If the read spans object boundary, just do multiple reads.
 523 */
 524static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to,
 525			      int *checkeof)
 526{
 527	struct file *file = iocb->ki_filp;
 528	struct inode *inode = file_inode(file);
 529	struct page **pages;
 530	u64 off = iocb->ki_pos;
 531	int num_pages;
 532	ssize_t ret;
 533	size_t len = iov_iter_count(to);
 534
 535	dout("sync_read on file %p %llu~%u %s\n", file, off,
 536	     (unsigned)len,
 537	     (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
 538
 539	if (!len)
 540		return 0;
 541	/*
 542	 * flush any page cache pages in this range.  this
 543	 * will make concurrent normal and sync io slow,
 544	 * but it will at least behave sensibly when they are
 545	 * in sequence.
 546	 */
 547	ret = filemap_write_and_wait_range(inode->i_mapping, off,
 548						off + len);
 549	if (ret < 0)
 550		return ret;
 551
 552	if (unlikely(to->type & ITER_PIPE)) {
 553		size_t page_off;
 554		ret = iov_iter_get_pages_alloc(to, &pages, len,
 555					       &page_off);
 556		if (ret <= 0)
 557			return -ENOMEM;
 558		num_pages = DIV_ROUND_UP(ret + page_off, PAGE_SIZE);
 559
 560		ret = striped_read(inode, off, ret, pages, num_pages,
 561				   page_off, checkeof);
 562		if (ret > 0) {
 563			iov_iter_advance(to, ret);
 564			off += ret;
 565		} else {
 566			iov_iter_advance(to, 0);
 
 
 
 
 567		}
 568		ceph_put_page_vector(pages, num_pages, false);
 569	} else {
 570		num_pages = calc_pages_for(off, len);
 571		pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
 572		if (IS_ERR(pages))
 573			return PTR_ERR(pages);
 574
 575		ret = striped_read(inode, off, len, pages, num_pages,
 576				   (off & ~PAGE_MASK), checkeof);
 577		if (ret > 0) {
 578			int l, k = 0;
 579			size_t left = ret;
 580
 581			while (left) {
 582				size_t page_off = off & ~PAGE_MASK;
 583				size_t copy = min_t(size_t, left,
 584						    PAGE_SIZE - page_off);
 585				l = copy_page_to_iter(pages[k++], page_off,
 586						      copy, to);
 587				off += l;
 588				left -= l;
 589				if (l < copy)
 590					break;
 591			}
 592		}
 593		ceph_release_page_vector(pages, num_pages);
 594	}
 
 595
 596	if (off > iocb->ki_pos) {
 597		ret = off - iocb->ki_pos;
 598		iocb->ki_pos = off;
 599	}
 600
 601	dout("sync_read result %zd\n", ret);
 602	return ret;
 603}
 604
 605struct ceph_aio_request {
 606	struct kiocb *iocb;
 607	size_t total_len;
 608	int write;
 609	int error;
 610	struct list_head osd_reqs;
 611	unsigned num_reqs;
 612	atomic_t pending_reqs;
 613	struct timespec mtime;
 614	struct ceph_cap_flush *prealloc_cf;
 615};
 616
 617struct ceph_aio_work {
 618	struct work_struct work;
 619	struct ceph_osd_request *req;
 620};
 621
 622static void ceph_aio_retry_work(struct work_struct *work);
 623
 624static void ceph_aio_complete(struct inode *inode,
 625			      struct ceph_aio_request *aio_req)
 626{
 627	struct ceph_inode_info *ci = ceph_inode(inode);
 628	int ret;
 629
 630	if (!atomic_dec_and_test(&aio_req->pending_reqs))
 631		return;
 632
 633	ret = aio_req->error;
 634	if (!ret)
 635		ret = aio_req->total_len;
 636
 637	dout("ceph_aio_complete %p rc %d\n", inode, ret);
 638
 639	if (ret >= 0 && aio_req->write) {
 640		int dirty;
 641
 642		loff_t endoff = aio_req->iocb->ki_pos + aio_req->total_len;
 643		if (endoff > i_size_read(inode)) {
 644			if (ceph_inode_set_size(inode, endoff))
 645				ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
 646		}
 647
 648		spin_lock(&ci->i_ceph_lock);
 649		ci->i_inline_version = CEPH_INLINE_NONE;
 650		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
 651					       &aio_req->prealloc_cf);
 652		spin_unlock(&ci->i_ceph_lock);
 653		if (dirty)
 654			__mark_inode_dirty(inode, dirty);
 655
 656	}
 657
 658	ceph_put_cap_refs(ci, (aio_req->write ? CEPH_CAP_FILE_WR :
 659						CEPH_CAP_FILE_RD));
 660
 661	aio_req->iocb->ki_complete(aio_req->iocb, ret, 0);
 662
 663	ceph_free_cap_flush(aio_req->prealloc_cf);
 664	kfree(aio_req);
 665}
 666
 667static void ceph_aio_complete_req(struct ceph_osd_request *req)
 
 668{
 669	int rc = req->r_result;
 670	struct inode *inode = req->r_inode;
 671	struct ceph_aio_request *aio_req = req->r_priv;
 672	struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
 673	int num_pages = calc_pages_for((u64)osd_data->alignment,
 674				       osd_data->length);
 675
 676	dout("ceph_aio_complete_req %p rc %d bytes %llu\n",
 677	     inode, rc, osd_data->length);
 678
 679	if (rc == -EOLDSNAPC) {
 680		struct ceph_aio_work *aio_work;
 681		BUG_ON(!aio_req->write);
 682
 683		aio_work = kmalloc(sizeof(*aio_work), GFP_NOFS);
 684		if (aio_work) {
 685			INIT_WORK(&aio_work->work, ceph_aio_retry_work);
 686			aio_work->req = req;
 687			queue_work(ceph_inode_to_client(inode)->wb_wq,
 688				   &aio_work->work);
 689			return;
 690		}
 691		rc = -ENOMEM;
 692	} else if (!aio_req->write) {
 693		if (rc == -ENOENT)
 694			rc = 0;
 695		if (rc >= 0 && osd_data->length > rc) {
 696			int zoff = osd_data->alignment + rc;
 697			int zlen = osd_data->length - rc;
 698			/*
 699			 * If read is satisfied by single OSD request,
 700			 * it can pass EOF. Otherwise read is within
 701			 * i_size.
 702			 */
 703			if (aio_req->num_reqs == 1) {
 704				loff_t i_size = i_size_read(inode);
 705				loff_t endoff = aio_req->iocb->ki_pos + rc;
 706				if (endoff < i_size)
 707					zlen = min_t(size_t, zlen,
 708						     i_size - endoff);
 709				aio_req->total_len = rc + zlen;
 710			}
 711
 712			if (zlen > 0)
 713				ceph_zero_page_vector_range(zoff, zlen,
 714							    osd_data->pages);
 715		}
 716	}
 717
 718	ceph_put_page_vector(osd_data->pages, num_pages, !aio_req->write);
 719	ceph_osdc_put_request(req);
 720
 721	if (rc < 0)
 722		cmpxchg(&aio_req->error, 0, rc);
 723
 724	ceph_aio_complete(inode, aio_req);
 725	return;
 726}
 727
 728static void ceph_aio_retry_work(struct work_struct *work)
 729{
 730	struct ceph_aio_work *aio_work =
 731		container_of(work, struct ceph_aio_work, work);
 732	struct ceph_osd_request *orig_req = aio_work->req;
 733	struct ceph_aio_request *aio_req = orig_req->r_priv;
 734	struct inode *inode = orig_req->r_inode;
 735	struct ceph_inode_info *ci = ceph_inode(inode);
 736	struct ceph_snap_context *snapc;
 737	struct ceph_osd_request *req;
 738	int ret;
 739
 740	spin_lock(&ci->i_ceph_lock);
 741	if (__ceph_have_pending_cap_snap(ci)) {
 742		struct ceph_cap_snap *capsnap =
 743			list_last_entry(&ci->i_cap_snaps,
 744					struct ceph_cap_snap,
 745					ci_item);
 746		snapc = ceph_get_snap_context(capsnap->context);
 747	} else {
 748		BUG_ON(!ci->i_head_snapc);
 749		snapc = ceph_get_snap_context(ci->i_head_snapc);
 750	}
 751	spin_unlock(&ci->i_ceph_lock);
 752
 753	req = ceph_osdc_alloc_request(orig_req->r_osdc, snapc, 2,
 754			false, GFP_NOFS);
 755	if (!req) {
 756		ret = -ENOMEM;
 757		req = orig_req;
 758		goto out;
 759	}
 760
 761	req->r_flags =	CEPH_OSD_FLAG_ORDERSNAP |
 762			CEPH_OSD_FLAG_ONDISK |
 763			CEPH_OSD_FLAG_WRITE;
 764	ceph_oloc_copy(&req->r_base_oloc, &orig_req->r_base_oloc);
 765	ceph_oid_copy(&req->r_base_oid, &orig_req->r_base_oid);
 766
 767	ret = ceph_osdc_alloc_messages(req, GFP_NOFS);
 768	if (ret) {
 769		ceph_osdc_put_request(req);
 770		req = orig_req;
 771		goto out;
 772	}
 773
 774	req->r_ops[0] = orig_req->r_ops[0];
 775	osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC, 0);
 776
 777	req->r_mtime = aio_req->mtime;
 778	req->r_data_offset = req->r_ops[0].extent.offset;
 779
 780	ceph_osdc_put_request(orig_req);
 781
 782	req->r_callback = ceph_aio_complete_req;
 783	req->r_inode = inode;
 784	req->r_priv = aio_req;
 785
 786	ret = ceph_osdc_start_request(req->r_osdc, req, false);
 787out:
 788	if (ret < 0) {
 789		req->r_result = ret;
 790		ceph_aio_complete_req(req);
 791	}
 792
 793	ceph_put_snap_context(snapc);
 794	kfree(aio_work);
 795}
 796
 797/*
 798 * Write commit request unsafe callback, called to tell us when a
 799 * request is unsafe (that is, in flight--has been handed to the
 800 * messenger to send to its target osd).  It is called again when
 801 * we've received a response message indicating the request is
 802 * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
 803 * is completed early (and unsuccessfully) due to a timeout or
 804 * interrupt.
 805 *
 806 * This is used if we requested both an ACK and ONDISK commit reply
 807 * from the OSD.
 808 */
 809static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
 810{
 811	struct ceph_inode_info *ci = ceph_inode(req->r_inode);
 812
 813	dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
 814		unsafe ? "un" : "");
 815	if (unsafe) {
 816		ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
 817		spin_lock(&ci->i_unsafe_lock);
 818		list_add_tail(&req->r_unsafe_item,
 819			      &ci->i_unsafe_writes);
 820		spin_unlock(&ci->i_unsafe_lock);
 821
 822		complete_all(&req->r_completion);
 823	} else {
 824		spin_lock(&ci->i_unsafe_lock);
 825		list_del_init(&req->r_unsafe_item);
 826		spin_unlock(&ci->i_unsafe_lock);
 827		ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
 828	}
 829}
 830
 831/*
 832 * Wait on any unsafe replies for the given inode.  First wait on the
 833 * newest request, and make that the upper bound.  Then, if there are
 834 * more requests, keep waiting on the oldest as long as it is still older
 835 * than the original request.
 836 */
 837void ceph_sync_write_wait(struct inode *inode)
 838{
 839	struct ceph_inode_info *ci = ceph_inode(inode);
 840	struct list_head *head = &ci->i_unsafe_writes;
 841	struct ceph_osd_request *req;
 842	u64 last_tid;
 843
 844	if (!S_ISREG(inode->i_mode))
 845		return;
 846
 847	spin_lock(&ci->i_unsafe_lock);
 848	if (list_empty(head))
 849		goto out;
 850
 851	/* set upper bound as _last_ entry in chain */
 852
 853	req = list_last_entry(head, struct ceph_osd_request,
 854			      r_unsafe_item);
 855	last_tid = req->r_tid;
 856
 857	do {
 858		ceph_osdc_get_request(req);
 859		spin_unlock(&ci->i_unsafe_lock);
 860
 861		dout("sync_write_wait on tid %llu (until %llu)\n",
 862		     req->r_tid, last_tid);
 863		wait_for_completion(&req->r_done_completion);
 864		ceph_osdc_put_request(req);
 865
 866		spin_lock(&ci->i_unsafe_lock);
 867		/*
 868		 * from here on look at first entry in chain, since we
 869		 * only want to wait for anything older than last_tid
 870		 */
 871		if (list_empty(head))
 872			break;
 873		req = list_first_entry(head, struct ceph_osd_request,
 874				       r_unsafe_item);
 875	} while (req->r_tid < last_tid);
 876out:
 877	spin_unlock(&ci->i_unsafe_lock);
 878}
 879
 880static ssize_t
 881ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
 882		       struct ceph_snap_context *snapc,
 883		       struct ceph_cap_flush **pcf)
 884{
 885	struct file *file = iocb->ki_filp;
 886	struct inode *inode = file_inode(file);
 887	struct ceph_inode_info *ci = ceph_inode(inode);
 888	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 889	struct ceph_vino vino;
 890	struct ceph_osd_request *req;
 891	struct page **pages;
 892	struct ceph_aio_request *aio_req = NULL;
 893	int num_pages = 0;
 894	int flags;
 895	int ret;
 896	struct timespec mtime = current_time(inode);
 897	size_t count = iov_iter_count(iter);
 898	loff_t pos = iocb->ki_pos;
 899	bool write = iov_iter_rw(iter) == WRITE;
 900
 901	if (write && ceph_snap(file_inode(file)) != CEPH_NOSNAP)
 902		return -EROFS;
 903
 904	dout("sync_direct_read_write (%s) on file %p %lld~%u\n",
 905	     (write ? "write" : "read"), file, pos, (unsigned)count);
 906
 907	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
 908	if (ret < 0)
 909		return ret;
 910
 911	if (write) {
 912		int ret2 = invalidate_inode_pages2_range(inode->i_mapping,
 913					pos >> PAGE_SHIFT,
 914					(pos + count) >> PAGE_SHIFT);
 915		if (ret2 < 0)
 916			dout("invalidate_inode_pages2_range returned %d\n", ret2);
 917
 918		flags = CEPH_OSD_FLAG_ORDERSNAP |
 919			CEPH_OSD_FLAG_ONDISK |
 920			CEPH_OSD_FLAG_WRITE;
 921	} else {
 922		flags = CEPH_OSD_FLAG_READ;
 923	}
 924
 925	while (iov_iter_count(iter) > 0) {
 926		u64 size = dio_get_pagev_size(iter);
 927		size_t start = 0;
 928		ssize_t len;
 929
 930		vino = ceph_vino(inode);
 931		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
 932					    vino, pos, &size, 0,
 933					    /*include a 'startsync' command*/
 934					    write ? 2 : 1,
 935					    write ? CEPH_OSD_OP_WRITE :
 936						    CEPH_OSD_OP_READ,
 937					    flags, snapc,
 938					    ci->i_truncate_seq,
 939					    ci->i_truncate_size,
 940					    false);
 941		if (IS_ERR(req)) {
 942			ret = PTR_ERR(req);
 943			break;
 944		}
 945
 946		len = size;
 947		pages = dio_get_pages_alloc(iter, len, &start, &num_pages);
 948		if (IS_ERR(pages)) {
 949			ceph_osdc_put_request(req);
 950			ret = PTR_ERR(pages);
 951			break;
 952		}
 953
 954		/*
 955		 * To simplify error handling, allow AIO when IO within i_size
 956		 * or IO can be satisfied by single OSD request.
 957		 */
 958		if (pos == iocb->ki_pos && !is_sync_kiocb(iocb) &&
 959		    (len == count || pos + count <= i_size_read(inode))) {
 960			aio_req = kzalloc(sizeof(*aio_req), GFP_KERNEL);
 961			if (aio_req) {
 962				aio_req->iocb = iocb;
 963				aio_req->write = write;
 964				INIT_LIST_HEAD(&aio_req->osd_reqs);
 965				if (write) {
 966					aio_req->mtime = mtime;
 967					swap(aio_req->prealloc_cf, *pcf);
 968				}
 969			}
 970			/* ignore error */
 971		}
 972
 973		if (write) {
 974			/*
 975			 * throw out any page cache pages in this range. this
 976			 * may block.
 977			 */
 978			truncate_inode_pages_range(inode->i_mapping, pos,
 979					(pos+len) | (PAGE_SIZE - 1));
 980
 981			osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC, 0);
 982			req->r_mtime = mtime;
 983		}
 984
 
 985		osd_req_op_extent_osd_data_pages(req, 0, pages, len, start,
 986						 false, false);
 987
 
 
 988		if (aio_req) {
 989			aio_req->total_len += len;
 990			aio_req->num_reqs++;
 991			atomic_inc(&aio_req->pending_reqs);
 992
 993			req->r_callback = ceph_aio_complete_req;
 994			req->r_inode = inode;
 995			req->r_priv = aio_req;
 996			list_add_tail(&req->r_unsafe_item, &aio_req->osd_reqs);
 997
 998			pos += len;
 999			iov_iter_advance(iter, len);
1000			continue;
1001		}
1002
1003		ret = ceph_osdc_start_request(req->r_osdc, req, false);
1004		if (!ret)
1005			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1006
1007		size = i_size_read(inode);
1008		if (!write) {
1009			if (ret == -ENOENT)
1010				ret = 0;
1011			if (ret >= 0 && ret < len && pos + ret < size) {
1012				int zlen = min_t(size_t, len - ret,
1013						 size - pos - ret);
1014				ceph_zero_page_vector_range(start + ret, zlen,
1015							    pages);
1016				ret += zlen;
1017			}
1018			if (ret >= 0)
1019				len = ret;
1020		}
1021
1022		ceph_put_page_vector(pages, num_pages, !write);
1023
1024		ceph_osdc_put_request(req);
1025		if (ret < 0)
1026			break;
1027
1028		pos += len;
1029		iov_iter_advance(iter, len);
1030
1031		if (!write && pos >= size)
1032			break;
1033
1034		if (write && pos > size) {
1035			if (ceph_inode_set_size(inode, pos))
1036				ceph_check_caps(ceph_inode(inode),
1037						CHECK_CAPS_AUTHONLY,
1038						NULL);
1039		}
1040	}
1041
1042	if (aio_req) {
1043		LIST_HEAD(osd_reqs);
1044
1045		if (aio_req->num_reqs == 0) {
1046			kfree(aio_req);
1047			return ret;
1048		}
1049
1050		ceph_get_cap_refs(ci, write ? CEPH_CAP_FILE_WR :
1051					      CEPH_CAP_FILE_RD);
1052
1053		list_splice(&aio_req->osd_reqs, &osd_reqs);
1054		while (!list_empty(&osd_reqs)) {
1055			req = list_first_entry(&osd_reqs,
1056					       struct ceph_osd_request,
1057					       r_unsafe_item);
1058			list_del_init(&req->r_unsafe_item);
1059			if (ret >= 0)
1060				ret = ceph_osdc_start_request(req->r_osdc,
1061							      req, false);
1062			if (ret < 0) {
1063				req->r_result = ret;
1064				ceph_aio_complete_req(req);
1065			}
1066		}
1067		return -EIOCBQUEUED;
1068	}
1069
1070	if (ret != -EOLDSNAPC && pos > iocb->ki_pos) {
1071		ret = pos - iocb->ki_pos;
1072		iocb->ki_pos = pos;
1073	}
1074	return ret;
1075}
1076
1077/*
1078 * Synchronous write, straight from __user pointer or user pages.
1079 *
1080 * If write spans object boundary, just do multiple writes.  (For a
1081 * correct atomic write, we should e.g. take write locks on all
1082 * objects, rollback on failure, etc.)
1083 */
1084static ssize_t
1085ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos,
1086		struct ceph_snap_context *snapc)
1087{
1088	struct file *file = iocb->ki_filp;
1089	struct inode *inode = file_inode(file);
1090	struct ceph_inode_info *ci = ceph_inode(inode);
1091	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1092	struct ceph_vino vino;
1093	struct ceph_osd_request *req;
1094	struct page **pages;
1095	u64 len;
1096	int num_pages;
1097	int written = 0;
1098	int flags;
1099	int check_caps = 0;
1100	int ret;
1101	struct timespec mtime = current_time(inode);
1102	size_t count = iov_iter_count(from);
1103
1104	if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
1105		return -EROFS;
1106
1107	dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
1108
1109	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
1110	if (ret < 0)
1111		return ret;
1112
1113	ret = invalidate_inode_pages2_range(inode->i_mapping,
1114					    pos >> PAGE_SHIFT,
1115					    (pos + count) >> PAGE_SHIFT);
1116	if (ret < 0)
1117		dout("invalidate_inode_pages2_range returned %d\n", ret);
1118
1119	flags = CEPH_OSD_FLAG_ORDERSNAP |
1120		CEPH_OSD_FLAG_ONDISK |
1121		CEPH_OSD_FLAG_WRITE |
1122		CEPH_OSD_FLAG_ACK;
1123
1124	while ((len = iov_iter_count(from)) > 0) {
1125		size_t left;
1126		int n;
1127
1128		vino = ceph_vino(inode);
1129		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1130					    vino, pos, &len, 0, 1,
1131					    CEPH_OSD_OP_WRITE, flags, snapc,
1132					    ci->i_truncate_seq,
1133					    ci->i_truncate_size,
1134					    false);
1135		if (IS_ERR(req)) {
1136			ret = PTR_ERR(req);
1137			break;
1138		}
1139
1140		/*
1141		 * write from beginning of first page,
1142		 * regardless of io alignment
1143		 */
1144		num_pages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
1145
1146		pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
1147		if (IS_ERR(pages)) {
1148			ret = PTR_ERR(pages);
1149			goto out;
1150		}
1151
1152		left = len;
1153		for (n = 0; n < num_pages; n++) {
1154			size_t plen = min_t(size_t, left, PAGE_SIZE);
1155			ret = copy_page_from_iter(pages[n], 0, plen, from);
1156			if (ret != plen) {
1157				ret = -EFAULT;
1158				break;
1159			}
1160			left -= ret;
1161		}
1162
1163		if (ret < 0) {
1164			ceph_release_page_vector(pages, num_pages);
1165			goto out;
1166		}
1167
1168		/* get a second commit callback */
1169		req->r_unsafe_callback = ceph_sync_write_unsafe;
1170		req->r_inode = inode;
1171
1172		osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
1173						false, true);
1174
1175		req->r_mtime = mtime;
 
 
1176		ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1177		if (!ret)
1178			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1179
1180out:
1181		ceph_osdc_put_request(req);
1182		if (ret == 0) {
1183			pos += len;
1184			written += len;
1185
1186			if (pos > i_size_read(inode)) {
1187				check_caps = ceph_inode_set_size(inode, pos);
1188				if (check_caps)
1189					ceph_check_caps(ceph_inode(inode),
1190							CHECK_CAPS_AUTHONLY,
1191							NULL);
1192			}
1193		} else
1194			break;
1195	}
1196
1197	if (ret != -EOLDSNAPC && written > 0) {
1198		ret = written;
1199		iocb->ki_pos = pos;
1200	}
1201	return ret;
1202}
1203
1204/*
1205 * Wrap generic_file_aio_read with checks for cap bits on the inode.
1206 * Atomically grab references, so that those bits are not released
1207 * back to the MDS mid-read.
1208 *
1209 * Hmm, the sync read case isn't actually async... should it be?
1210 */
1211static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
1212{
1213	struct file *filp = iocb->ki_filp;
1214	struct ceph_file_info *fi = filp->private_data;
1215	size_t len = iov_iter_count(to);
1216	struct inode *inode = file_inode(filp);
1217	struct ceph_inode_info *ci = ceph_inode(inode);
1218	struct page *pinned_page = NULL;
1219	ssize_t ret;
1220	int want, got = 0;
1221	int retry_op = 0, read = 0;
1222
1223again:
1224	dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
1225	     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
1226
1227	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1228		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
1229	else
1230		want = CEPH_CAP_FILE_CACHE;
1231	ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page);
1232	if (ret < 0)
1233		return ret;
1234
1235	if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
1236	    (iocb->ki_flags & IOCB_DIRECT) ||
1237	    (fi->flags & CEPH_F_SYNC)) {
1238
1239		dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
1240		     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
1241		     ceph_cap_string(got));
1242
1243		if (ci->i_inline_version == CEPH_INLINE_NONE) {
1244			if (!retry_op && (iocb->ki_flags & IOCB_DIRECT)) {
1245				ret = ceph_direct_read_write(iocb, to,
1246							     NULL, NULL);
1247				if (ret >= 0 && ret < len)
1248					retry_op = CHECK_EOF;
1249			} else {
1250				ret = ceph_sync_read(iocb, to, &retry_op);
1251			}
1252		} else {
1253			retry_op = READ_INLINE;
1254		}
1255	} else {
1256		dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
1257		     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
1258		     ceph_cap_string(got));
1259		current->journal_info = filp;
1260		ret = generic_file_read_iter(iocb, to);
1261		current->journal_info = NULL;
1262	}
1263	dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
1264	     inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
1265	if (pinned_page) {
1266		put_page(pinned_page);
1267		pinned_page = NULL;
1268	}
1269	ceph_put_cap_refs(ci, got);
1270	if (retry_op > HAVE_RETRIED && ret >= 0) {
1271		int statret;
1272		struct page *page = NULL;
1273		loff_t i_size;
1274		if (retry_op == READ_INLINE) {
1275			page = __page_cache_alloc(GFP_KERNEL);
1276			if (!page)
1277				return -ENOMEM;
1278		}
1279
1280		statret = __ceph_do_getattr(inode, page,
1281					    CEPH_STAT_CAP_INLINE_DATA, !!page);
1282		if (statret < 0) {
1283			if (page)
1284				__free_page(page);
1285			if (statret == -ENODATA) {
1286				BUG_ON(retry_op != READ_INLINE);
1287				goto again;
1288			}
1289			return statret;
1290		}
1291
1292		i_size = i_size_read(inode);
1293		if (retry_op == READ_INLINE) {
1294			BUG_ON(ret > 0 || read > 0);
1295			if (iocb->ki_pos < i_size &&
1296			    iocb->ki_pos < PAGE_SIZE) {
1297				loff_t end = min_t(loff_t, i_size,
1298						   iocb->ki_pos + len);
1299				end = min_t(loff_t, end, PAGE_SIZE);
1300				if (statret < end)
1301					zero_user_segment(page, statret, end);
1302				ret = copy_page_to_iter(page,
1303						iocb->ki_pos & ~PAGE_MASK,
1304						end - iocb->ki_pos, to);
1305				iocb->ki_pos += ret;
1306				read += ret;
1307			}
1308			if (iocb->ki_pos < i_size && read < len) {
1309				size_t zlen = min_t(size_t, len - read,
1310						    i_size - iocb->ki_pos);
1311				ret = iov_iter_zero(zlen, to);
1312				iocb->ki_pos += ret;
1313				read += ret;
1314			}
1315			__free_pages(page, 0);
1316			return read;
1317		}
1318
1319		/* hit EOF or hole? */
1320		if (retry_op == CHECK_EOF && iocb->ki_pos < i_size &&
1321		    ret < len) {
1322			dout("sync_read hit hole, ppos %lld < size %lld"
1323			     ", reading more\n", iocb->ki_pos, i_size);
1324
1325			read += ret;
1326			len -= ret;
1327			retry_op = HAVE_RETRIED;
1328			goto again;
1329		}
1330	}
1331
1332	if (ret >= 0)
1333		ret += read;
1334
1335	return ret;
1336}
1337
1338/*
1339 * Take cap references to avoid releasing caps to MDS mid-write.
1340 *
1341 * If we are synchronous, and write with an old snap context, the OSD
1342 * may return EOLDSNAPC.  In that case, retry the write.. _after_
1343 * dropping our cap refs and allowing the pending snap to logically
1344 * complete _before_ this write occurs.
1345 *
1346 * If we are near ENOSPC, write synchronously.
1347 */
1348static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
1349{
1350	struct file *file = iocb->ki_filp;
1351	struct ceph_file_info *fi = file->private_data;
1352	struct inode *inode = file_inode(file);
1353	struct ceph_inode_info *ci = ceph_inode(inode);
1354	struct ceph_osd_client *osdc =
1355		&ceph_sb_to_client(inode->i_sb)->client->osdc;
1356	struct ceph_cap_flush *prealloc_cf;
1357	ssize_t count, written = 0;
1358	int err, want, got;
1359	loff_t pos;
1360
1361	if (ceph_snap(inode) != CEPH_NOSNAP)
1362		return -EROFS;
1363
1364	prealloc_cf = ceph_alloc_cap_flush();
1365	if (!prealloc_cf)
1366		return -ENOMEM;
1367
1368	inode_lock(inode);
1369
1370	/* We can write back this queue in page reclaim */
1371	current->backing_dev_info = inode_to_bdi(inode);
1372
1373	if (iocb->ki_flags & IOCB_APPEND) {
1374		err = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1375		if (err < 0)
1376			goto out;
1377	}
1378
1379	err = generic_write_checks(iocb, from);
1380	if (err <= 0)
1381		goto out;
1382
1383	pos = iocb->ki_pos;
1384	count = iov_iter_count(from);
1385	err = file_remove_privs(file);
1386	if (err)
1387		goto out;
1388
1389	err = file_update_time(file);
1390	if (err)
1391		goto out;
1392
1393	if (ci->i_inline_version != CEPH_INLINE_NONE) {
1394		err = ceph_uninline_data(file, NULL);
1395		if (err < 0)
1396			goto out;
1397	}
1398
1399retry_snap:
1400	if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL)) {
1401		err = -ENOSPC;
1402		goto out;
1403	}
1404
1405	dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
1406	     inode, ceph_vinop(inode), pos, count, i_size_read(inode));
1407	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1408		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1409	else
1410		want = CEPH_CAP_FILE_BUFFER;
1411	got = 0;
1412	err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, pos + count,
1413			    &got, NULL);
1414	if (err < 0)
1415		goto out;
1416
1417	dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
1418	     inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
1419
1420	if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
1421	    (iocb->ki_flags & IOCB_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
1422		struct ceph_snap_context *snapc;
1423		struct iov_iter data;
1424		inode_unlock(inode);
1425
1426		spin_lock(&ci->i_ceph_lock);
1427		if (__ceph_have_pending_cap_snap(ci)) {
1428			struct ceph_cap_snap *capsnap =
1429					list_last_entry(&ci->i_cap_snaps,
1430							struct ceph_cap_snap,
1431							ci_item);
1432			snapc = ceph_get_snap_context(capsnap->context);
1433		} else {
1434			BUG_ON(!ci->i_head_snapc);
1435			snapc = ceph_get_snap_context(ci->i_head_snapc);
1436		}
1437		spin_unlock(&ci->i_ceph_lock);
1438
1439		/* we might need to revert back to that point */
1440		data = *from;
1441		if (iocb->ki_flags & IOCB_DIRECT)
1442			written = ceph_direct_read_write(iocb, &data, snapc,
1443							 &prealloc_cf);
1444		else
1445			written = ceph_sync_write(iocb, &data, pos, snapc);
1446		if (written == -EOLDSNAPC) {
1447			dout("aio_write %p %llx.%llx %llu~%u"
1448				"got EOLDSNAPC, retrying\n",
1449				inode, ceph_vinop(inode),
1450				pos, (unsigned)count);
1451			inode_lock(inode);
1452			goto retry_snap;
1453		}
1454		if (written > 0)
1455			iov_iter_advance(from, written);
1456		ceph_put_snap_context(snapc);
1457	} else {
 
1458		/*
1459		 * No need to acquire the i_truncate_mutex. Because
1460		 * the MDS revokes Fwb caps before sending truncate
1461		 * message to us. We can't get Fwb cap while there
1462		 * are pending vmtruncate. So write and vmtruncate
1463		 * can not run at the same time
1464		 */
1465		written = generic_perform_write(file, from, pos);
1466		if (likely(written >= 0))
1467			iocb->ki_pos = pos + written;
 
 
1468		inode_unlock(inode);
1469	}
1470
1471	if (written >= 0) {
1472		int dirty;
1473		spin_lock(&ci->i_ceph_lock);
1474		ci->i_inline_version = CEPH_INLINE_NONE;
1475		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1476					       &prealloc_cf);
1477		spin_unlock(&ci->i_ceph_lock);
1478		if (dirty)
1479			__mark_inode_dirty(inode, dirty);
1480	}
1481
1482	dout("aio_write %p %llx.%llx %llu~%u  dropping cap refs on %s\n",
1483	     inode, ceph_vinop(inode), pos, (unsigned)count,
1484	     ceph_cap_string(got));
1485	ceph_put_cap_refs(ci, got);
1486
1487	if (written >= 0) {
1488		if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_NEARFULL))
1489			iocb->ki_flags |= IOCB_DSYNC;
1490
1491		written = generic_write_sync(iocb, written);
 
1492	}
1493
1494	goto out_unlocked;
1495
1496out:
1497	inode_unlock(inode);
1498out_unlocked:
1499	ceph_free_cap_flush(prealloc_cf);
1500	current->backing_dev_info = NULL;
1501	return written ? written : err;
1502}
1503
1504/*
1505 * llseek.  be sure to verify file size on SEEK_END.
1506 */
1507static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
1508{
1509	struct inode *inode = file->f_mapping->host;
1510	loff_t i_size;
1511	loff_t ret;
1512
1513	inode_lock(inode);
1514
1515	if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
1516		ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1517		if (ret < 0)
 
1518			goto out;
 
1519	}
1520
1521	i_size = i_size_read(inode);
1522	switch (whence) {
1523	case SEEK_END:
1524		offset += i_size;
1525		break;
1526	case SEEK_CUR:
1527		/*
1528		 * Here we special-case the lseek(fd, 0, SEEK_CUR)
1529		 * position-querying operation.  Avoid rewriting the "same"
1530		 * f_pos value back to the file because a concurrent read(),
1531		 * write() or lseek() might have altered it
1532		 */
1533		if (offset == 0) {
1534			ret = file->f_pos;
1535			goto out;
1536		}
1537		offset += file->f_pos;
1538		break;
1539	case SEEK_DATA:
1540		if (offset >= i_size) {
1541			ret = -ENXIO;
1542			goto out;
1543		}
1544		break;
1545	case SEEK_HOLE:
1546		if (offset >= i_size) {
1547			ret = -ENXIO;
1548			goto out;
1549		}
1550		offset = i_size;
1551		break;
1552	}
1553
1554	ret = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1555
1556out:
1557	inode_unlock(inode);
1558	return ret;
1559}
1560
1561static inline void ceph_zero_partial_page(
1562	struct inode *inode, loff_t offset, unsigned size)
1563{
1564	struct page *page;
1565	pgoff_t index = offset >> PAGE_SHIFT;
1566
1567	page = find_lock_page(inode->i_mapping, index);
1568	if (page) {
1569		wait_on_page_writeback(page);
1570		zero_user(page, offset & (PAGE_SIZE - 1), size);
1571		unlock_page(page);
1572		put_page(page);
1573	}
1574}
1575
1576static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1577				      loff_t length)
1578{
1579	loff_t nearly = round_up(offset, PAGE_SIZE);
1580	if (offset < nearly) {
1581		loff_t size = nearly - offset;
1582		if (length < size)
1583			size = length;
1584		ceph_zero_partial_page(inode, offset, size);
1585		offset += size;
1586		length -= size;
1587	}
1588	if (length >= PAGE_SIZE) {
1589		loff_t size = round_down(length, PAGE_SIZE);
1590		truncate_pagecache_range(inode, offset, offset + size - 1);
1591		offset += size;
1592		length -= size;
1593	}
1594	if (length)
1595		ceph_zero_partial_page(inode, offset, length);
1596}
1597
1598static int ceph_zero_partial_object(struct inode *inode,
1599				    loff_t offset, loff_t *length)
1600{
1601	struct ceph_inode_info *ci = ceph_inode(inode);
1602	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1603	struct ceph_osd_request *req;
1604	int ret = 0;
1605	loff_t zero = 0;
1606	int op;
1607
1608	if (!length) {
1609		op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1610		length = &zero;
1611	} else {
1612		op = CEPH_OSD_OP_ZERO;
1613	}
1614
1615	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1616					ceph_vino(inode),
1617					offset, length,
1618					0, 1, op,
1619					CEPH_OSD_FLAG_WRITE |
1620					CEPH_OSD_FLAG_ONDISK,
1621					NULL, 0, 0, false);
1622	if (IS_ERR(req)) {
1623		ret = PTR_ERR(req);
1624		goto out;
1625	}
1626
1627	req->r_mtime = inode->i_mtime;
 
 
1628	ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1629	if (!ret) {
1630		ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1631		if (ret == -ENOENT)
1632			ret = 0;
1633	}
1634	ceph_osdc_put_request(req);
1635
1636out:
1637	return ret;
1638}
1639
1640static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1641{
1642	int ret = 0;
1643	struct ceph_inode_info *ci = ceph_inode(inode);
1644	s32 stripe_unit = ci->i_layout.stripe_unit;
1645	s32 stripe_count = ci->i_layout.stripe_count;
1646	s32 object_size = ci->i_layout.object_size;
1647	u64 object_set_size = object_size * stripe_count;
1648	u64 nearly, t;
1649
1650	/* round offset up to next period boundary */
1651	nearly = offset + object_set_size - 1;
1652	t = nearly;
1653	nearly -= do_div(t, object_set_size);
1654
1655	while (length && offset < nearly) {
1656		loff_t size = length;
1657		ret = ceph_zero_partial_object(inode, offset, &size);
1658		if (ret < 0)
1659			return ret;
1660		offset += size;
1661		length -= size;
1662	}
1663	while (length >= object_set_size) {
1664		int i;
1665		loff_t pos = offset;
1666		for (i = 0; i < stripe_count; ++i) {
1667			ret = ceph_zero_partial_object(inode, pos, NULL);
1668			if (ret < 0)
1669				return ret;
1670			pos += stripe_unit;
1671		}
1672		offset += object_set_size;
1673		length -= object_set_size;
1674	}
1675	while (length) {
1676		loff_t size = length;
1677		ret = ceph_zero_partial_object(inode, offset, &size);
1678		if (ret < 0)
1679			return ret;
1680		offset += size;
1681		length -= size;
1682	}
1683	return ret;
1684}
1685
1686static long ceph_fallocate(struct file *file, int mode,
1687				loff_t offset, loff_t length)
1688{
1689	struct ceph_file_info *fi = file->private_data;
1690	struct inode *inode = file_inode(file);
1691	struct ceph_inode_info *ci = ceph_inode(inode);
1692	struct ceph_osd_client *osdc =
1693		&ceph_inode_to_client(inode)->client->osdc;
1694	struct ceph_cap_flush *prealloc_cf;
1695	int want, got = 0;
1696	int dirty;
1697	int ret = 0;
1698	loff_t endoff = 0;
1699	loff_t size;
1700
1701	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
1702		return -EOPNOTSUPP;
1703
1704	if (!S_ISREG(inode->i_mode))
1705		return -EOPNOTSUPP;
1706
1707	prealloc_cf = ceph_alloc_cap_flush();
1708	if (!prealloc_cf)
1709		return -ENOMEM;
1710
1711	inode_lock(inode);
1712
1713	if (ceph_snap(inode) != CEPH_NOSNAP) {
1714		ret = -EROFS;
1715		goto unlock;
1716	}
1717
1718	if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) &&
1719	    !(mode & FALLOC_FL_PUNCH_HOLE)) {
1720		ret = -ENOSPC;
1721		goto unlock;
1722	}
1723
1724	if (ci->i_inline_version != CEPH_INLINE_NONE) {
1725		ret = ceph_uninline_data(file, NULL);
1726		if (ret < 0)
1727			goto unlock;
1728	}
1729
1730	size = i_size_read(inode);
1731	if (!(mode & FALLOC_FL_KEEP_SIZE))
1732		endoff = offset + length;
1733
1734	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1735		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1736	else
1737		want = CEPH_CAP_FILE_BUFFER;
1738
1739	ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, endoff, &got, NULL);
1740	if (ret < 0)
1741		goto unlock;
1742
1743	if (mode & FALLOC_FL_PUNCH_HOLE) {
1744		if (offset < size)
1745			ceph_zero_pagecache_range(inode, offset, length);
1746		ret = ceph_zero_objects(inode, offset, length);
1747	} else if (endoff > size) {
1748		truncate_pagecache_range(inode, size, -1);
1749		if (ceph_inode_set_size(inode, endoff))
1750			ceph_check_caps(ceph_inode(inode),
1751				CHECK_CAPS_AUTHONLY, NULL);
1752	}
1753
1754	if (!ret) {
1755		spin_lock(&ci->i_ceph_lock);
1756		ci->i_inline_version = CEPH_INLINE_NONE;
1757		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1758					       &prealloc_cf);
1759		spin_unlock(&ci->i_ceph_lock);
1760		if (dirty)
1761			__mark_inode_dirty(inode, dirty);
1762	}
1763
1764	ceph_put_cap_refs(ci, got);
1765unlock:
1766	inode_unlock(inode);
1767	ceph_free_cap_flush(prealloc_cf);
1768	return ret;
1769}
1770
1771const struct file_operations ceph_file_fops = {
1772	.open = ceph_open,
1773	.release = ceph_release,
1774	.llseek = ceph_llseek,
1775	.read_iter = ceph_read_iter,
1776	.write_iter = ceph_write_iter,
1777	.mmap = ceph_mmap,
1778	.fsync = ceph_fsync,
1779	.lock = ceph_lock,
1780	.flock = ceph_flock,
1781	.splice_read = generic_file_splice_read,
1782	.splice_write = iter_file_splice_write,
1783	.unlocked_ioctl = ceph_ioctl,
1784	.compat_ioctl	= ceph_ioctl,
1785	.fallocate	= ceph_fallocate,
1786};
1787