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   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/aio.h>
  11#include <linux/falloc.h>
  12
  13#include "super.h"
  14#include "mds_client.h"
  15#include "cache.h"
  16
  17/*
  18 * Ceph file operations
  19 *
  20 * Implement basic open/close functionality, and implement
  21 * read/write.
  22 *
  23 * We implement three modes of file I/O:
  24 *  - buffered uses the generic_file_aio_{read,write} helpers
  25 *
  26 *  - synchronous is used when there is multi-client read/write
  27 *    sharing, avoids the page cache, and synchronously waits for an
  28 *    ack from the OSD.
  29 *
  30 *  - direct io takes the variant of the sync path that references
  31 *    user pages directly.
  32 *
  33 * fsync() flushes and waits on dirty pages, but just queues metadata
  34 * for writeback: since the MDS can recover size and mtime there is no
  35 * need to wait for MDS acknowledgement.
  36 */
  37
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  38
  39/*
  40 * Prepare an open request.  Preallocate ceph_cap to avoid an
  41 * inopportune ENOMEM later.
  42 */
  43static struct ceph_mds_request *
  44prepare_open_request(struct super_block *sb, int flags, int create_mode)
  45{
  46	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
  47	struct ceph_mds_client *mdsc = fsc->mdsc;
  48	struct ceph_mds_request *req;
  49	int want_auth = USE_ANY_MDS;
  50	int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
  51
  52	if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
  53		want_auth = USE_AUTH_MDS;
  54
  55	req = ceph_mdsc_create_request(mdsc, op, want_auth);
  56	if (IS_ERR(req))
  57		goto out;
  58	req->r_fmode = ceph_flags_to_mode(flags);
  59	req->r_args.open.flags = cpu_to_le32(flags);
  60	req->r_args.open.mode = cpu_to_le32(create_mode);
  61out:
  62	return req;
  63}
  64
  65/*
  66 * initialize private struct file data.
  67 * if we fail, clean up by dropping fmode reference on the ceph_inode
  68 */
  69static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
  70{
  71	struct ceph_file_info *cf;
  72	int ret = 0;
  73	struct ceph_inode_info *ci = ceph_inode(inode);
  74	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
  75	struct ceph_mds_client *mdsc = fsc->mdsc;
  76
  77	switch (inode->i_mode & S_IFMT) {
  78	case S_IFREG:
  79		/* First file open request creates the cookie, we want to keep
  80		 * this cookie around for the filetime of the inode as not to
  81		 * have to worry about fscache register / revoke / operation
  82		 * races.
  83		 *
  84		 * Also, if we know the operation is going to invalidate data
  85		 * (non readonly) just nuke the cache right away.
  86		 */
  87		ceph_fscache_register_inode_cookie(mdsc->fsc, ci);
  88		if ((fmode & CEPH_FILE_MODE_WR))
  89			ceph_fscache_invalidate(inode);
  90	case S_IFDIR:
  91		dout("init_file %p %p 0%o (regular)\n", inode, file,
  92		     inode->i_mode);
  93		cf = kmem_cache_alloc(ceph_file_cachep, GFP_NOFS | __GFP_ZERO);
  94		if (cf == NULL) {
  95			ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
  96			return -ENOMEM;
  97		}
  98		cf->fmode = fmode;
  99		cf->next_offset = 2;
 
 100		file->private_data = cf;
 101		BUG_ON(inode->i_fop->release != ceph_release);
 102		break;
 103
 104	case S_IFLNK:
 105		dout("init_file %p %p 0%o (symlink)\n", inode, file,
 106		     inode->i_mode);
 107		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 108		break;
 109
 110	default:
 111		dout("init_file %p %p 0%o (special)\n", inode, file,
 112		     inode->i_mode);
 113		/*
 114		 * we need to drop the open ref now, since we don't
 115		 * have .release set to ceph_release.
 116		 */
 117		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 118		BUG_ON(inode->i_fop->release == ceph_release);
 119
 120		/* call the proper open fop */
 121		ret = inode->i_fop->open(inode, file);
 122	}
 123	return ret;
 124}
 125
 126/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 127 * If we already have the requisite capabilities, we can satisfy
 128 * the open request locally (no need to request new caps from the
 129 * MDS).  We do, however, need to inform the MDS (asynchronously)
 130 * if our wanted caps set expands.
 131 */
 132int ceph_open(struct inode *inode, struct file *file)
 133{
 134	struct ceph_inode_info *ci = ceph_inode(inode);
 135	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
 136	struct ceph_mds_client *mdsc = fsc->mdsc;
 137	struct ceph_mds_request *req;
 138	struct ceph_file_info *cf = file->private_data;
 139	struct inode *parent_inode = NULL;
 140	int err;
 141	int flags, fmode, wanted;
 142
 143	if (cf) {
 144		dout("open file %p is already opened\n", file);
 145		return 0;
 146	}
 147
 148	/* filter out O_CREAT|O_EXCL; vfs did that already.  yuck. */
 149	flags = file->f_flags & ~(O_CREAT|O_EXCL);
 150	if (S_ISDIR(inode->i_mode))
 151		flags = O_DIRECTORY;  /* mds likes to know */
 152
 153	dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
 154	     ceph_vinop(inode), file, flags, file->f_flags);
 155	fmode = ceph_flags_to_mode(flags);
 156	wanted = ceph_caps_for_mode(fmode);
 157
 158	/* snapped files are read-only */
 159	if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
 160		return -EROFS;
 161
 162	/* trivially open snapdir */
 163	if (ceph_snap(inode) == CEPH_SNAPDIR) {
 164		spin_lock(&ci->i_ceph_lock);
 165		__ceph_get_fmode(ci, fmode);
 166		spin_unlock(&ci->i_ceph_lock);
 167		return ceph_init_file(inode, file, fmode);
 168	}
 169
 170	/*
 171	 * No need to block if we have caps on the auth MDS (for
 172	 * write) or any MDS (for read).  Update wanted set
 173	 * asynchronously.
 174	 */
 175	spin_lock(&ci->i_ceph_lock);
 176	if (__ceph_is_any_real_caps(ci) &&
 177	    (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
 178		int mds_wanted = __ceph_caps_mds_wanted(ci);
 179		int issued = __ceph_caps_issued(ci, NULL);
 180
 181		dout("open %p fmode %d want %s issued %s using existing\n",
 182		     inode, fmode, ceph_cap_string(wanted),
 183		     ceph_cap_string(issued));
 184		__ceph_get_fmode(ci, fmode);
 185		spin_unlock(&ci->i_ceph_lock);
 186
 187		/* adjust wanted? */
 188		if ((issued & wanted) != wanted &&
 189		    (mds_wanted & wanted) != wanted &&
 190		    ceph_snap(inode) != CEPH_SNAPDIR)
 191			ceph_check_caps(ci, 0, NULL);
 192
 193		return ceph_init_file(inode, file, fmode);
 194	} else if (ceph_snap(inode) != CEPH_NOSNAP &&
 195		   (ci->i_snap_caps & wanted) == wanted) {
 196		__ceph_get_fmode(ci, fmode);
 197		spin_unlock(&ci->i_ceph_lock);
 198		return ceph_init_file(inode, file, fmode);
 199	}
 200
 201	spin_unlock(&ci->i_ceph_lock);
 202
 203	dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
 204	req = prepare_open_request(inode->i_sb, flags, 0);
 205	if (IS_ERR(req)) {
 206		err = PTR_ERR(req);
 207		goto out;
 208	}
 209	req->r_inode = inode;
 210	ihold(inode);
 211
 212	req->r_num_caps = 1;
 213	if (flags & O_CREAT)
 214		parent_inode = ceph_get_dentry_parent_inode(file->f_dentry);
 215	err = ceph_mdsc_do_request(mdsc, parent_inode, req);
 216	iput(parent_inode);
 217	if (!err)
 218		err = ceph_init_file(inode, file, req->r_fmode);
 219	ceph_mdsc_put_request(req);
 220	dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
 221out:
 222	return err;
 223}
 224
 225
 226/*
 227 * Do a lookup + open with a single request.  If we get a non-existent
 228 * file or symlink, return 1 so the VFS can retry.
 229 */
 230int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 231		     struct file *file, unsigned flags, umode_t mode,
 232		     int *opened)
 233{
 234	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 235	struct ceph_mds_client *mdsc = fsc->mdsc;
 236	struct ceph_mds_request *req;
 237	struct dentry *dn;
 
 
 238	int err;
 239
 240	dout("atomic_open %p dentry %p '%.*s' %s flags %d mode 0%o\n",
 241	     dir, dentry, dentry->d_name.len, dentry->d_name.name,
 242	     d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
 243
 244	if (dentry->d_name.len > NAME_MAX)
 245		return -ENAMETOOLONG;
 246
 247	err = ceph_init_dentry(dentry);
 248	if (err < 0)
 249		return err;
 
 
 250
 251	/* do the open */
 252	req = prepare_open_request(dir->i_sb, flags, mode);
 253	if (IS_ERR(req))
 254		return PTR_ERR(req);
 
 
 255	req->r_dentry = dget(dentry);
 256	req->r_num_caps = 2;
 257	if (flags & O_CREAT) {
 258		req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 259		req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 
 
 
 
 260	}
 
 
 
 
 
 
 261	req->r_locked_dir = dir;           /* caller holds dir->i_mutex */
 262	err = ceph_mdsc_do_request(mdsc,
 263				   (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
 264				   req);
 
 265	if (err)
 266		goto out_err;
 267
 268	err = ceph_handle_snapdir(req, dentry, err);
 269	if (err == 0 && (flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
 270		err = ceph_handle_notrace_create(dir, dentry);
 271
 272	if (d_unhashed(dentry)) {
 273		dn = ceph_finish_lookup(req, dentry, err);
 274		if (IS_ERR(dn))
 275			err = PTR_ERR(dn);
 276	} else {
 277		/* we were given a hashed negative dentry */
 278		dn = NULL;
 279	}
 280	if (err)
 281		goto out_err;
 282	if (dn || dentry->d_inode == NULL || S_ISLNK(dentry->d_inode->i_mode)) {
 283		/* make vfs retry on splice, ENOENT, or symlink */
 284		dout("atomic_open finish_no_open on dn %p\n", dn);
 285		err = finish_no_open(file, dn);
 286	} else {
 287		dout("atomic_open finish_open on dn %p\n", dn);
 288		if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
 289			ceph_init_acl(dentry, dentry->d_inode, dir);
 290			*opened |= FILE_CREATED;
 291		}
 292		err = finish_open(file, dentry, ceph_open, opened);
 293	}
 294out_err:
 295	if (!req->r_err && req->r_target_inode)
 296		ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
 297	ceph_mdsc_put_request(req);
 
 
 298	dout("atomic_open result=%d\n", err);
 299	return err;
 300}
 301
 302int ceph_release(struct inode *inode, struct file *file)
 303{
 304	struct ceph_inode_info *ci = ceph_inode(inode);
 305	struct ceph_file_info *cf = file->private_data;
 306
 307	dout("release inode %p file %p\n", inode, file);
 308	ceph_put_fmode(ci, cf->fmode);
 309	if (cf->last_readdir)
 310		ceph_mdsc_put_request(cf->last_readdir);
 311	kfree(cf->last_name);
 312	kfree(cf->dir_info);
 313	dput(cf->dentry);
 314	kmem_cache_free(ceph_file_cachep, cf);
 315
 316	/* wake up anyone waiting for caps on this inode */
 317	wake_up_all(&ci->i_cap_wq);
 318	return 0;
 319}
 320
 
 
 
 
 
 
 321/*
 322 * Read a range of bytes striped over one or more objects.  Iterate over
 323 * objects we stripe over.  (That's not atomic, but good enough for now.)
 324 *
 325 * If we get a short result from the OSD, check against i_size; we need to
 326 * only return a short read to the caller if we hit EOF.
 327 */
 328static int striped_read(struct inode *inode,
 329			u64 off, u64 len,
 330			struct page **pages, int num_pages,
 331			int *checkeof, bool o_direct,
 332			unsigned long buf_align)
 333{
 334	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 335	struct ceph_inode_info *ci = ceph_inode(inode);
 336	u64 pos, this_len, left;
 337	int io_align, page_align;
 338	int pages_left;
 339	int read;
 340	struct page **page_pos;
 341	int ret;
 342	bool hit_stripe, was_short;
 343
 344	/*
 345	 * we may need to do multiple reads.  not atomic, unfortunately.
 346	 */
 347	pos = off;
 348	left = len;
 349	page_pos = pages;
 350	pages_left = num_pages;
 351	read = 0;
 352	io_align = off & ~PAGE_MASK;
 353
 354more:
 355	if (o_direct)
 356		page_align = (pos - io_align + buf_align) & ~PAGE_MASK;
 357	else
 358		page_align = pos & ~PAGE_MASK;
 359	this_len = left;
 360	ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
 361				  &ci->i_layout, pos, &this_len,
 362				  ci->i_truncate_seq,
 363				  ci->i_truncate_size,
 364				  page_pos, pages_left, page_align);
 365	if (ret == -ENOENT)
 366		ret = 0;
 367	hit_stripe = this_len < left;
 368	was_short = ret >= 0 && ret < this_len;
 369	dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, left, read,
 370	     ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
 371
 
 372	if (ret >= 0) {
 373		int didpages;
 374		if (was_short && (pos + ret < inode->i_size)) {
 375			u64 tmp = min(this_len - ret,
 376					inode->i_size - pos - ret);
 377			dout(" zero gap %llu to %llu\n",
 378				pos + ret, pos + ret + tmp);
 379			ceph_zero_page_vector_range(page_align + read + ret,
 380							tmp, pages);
 381			ret += tmp;
 382		}
 383
 384		didpages = (page_align + ret) >> PAGE_CACHE_SHIFT;
 385		pos += ret;
 386		read = pos - off;
 387		left -= ret;
 388		page_pos += didpages;
 389		pages_left -= didpages;
 390
 391		/* hit stripe and need continue*/
 392		if (left && hit_stripe && pos < inode->i_size)
 393			goto more;
 394	}
 395
 396	if (read > 0) {
 397		ret = read;
 398		/* did we bounce off eof? */
 399		if (pos + left > inode->i_size)
 400			*checkeof = 1;
 401	}
 402
 403	dout("striped_read returns %d\n", ret);
 404	return ret;
 405}
 406
 407/*
 408 * Completely synchronous read and write methods.  Direct from __user
 409 * buffer to osd, or directly to user pages (if O_DIRECT).
 410 *
 411 * If the read spans object boundary, just do multiple reads.
 412 */
 413static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
 414				int *checkeof)
 415{
 416	struct file *file = iocb->ki_filp;
 417	struct inode *inode = file_inode(file);
 418	struct page **pages;
 419	u64 off = iocb->ki_pos;
 420	int num_pages, ret;
 421	size_t len = i->count;
 
 422
 423	dout("sync_read on file %p %llu~%u %s\n", file, off,
 424	     (unsigned)len,
 425	     (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
 
 
 
 426	/*
 427	 * flush any page cache pages in this range.  this
 428	 * will make concurrent normal and sync io slow,
 429	 * but it will at least behave sensibly when they are
 430	 * in sequence.
 431	 */
 432	ret = filemap_write_and_wait_range(inode->i_mapping, off,
 433						off + len);
 434	if (ret < 0)
 435		return ret;
 436
 437	if (file->f_flags & O_DIRECT) {
 438		while (iov_iter_count(i)) {
 439			void __user *data = i->iov[0].iov_base + i->iov_offset;
 440			size_t len = i->iov[0].iov_len - i->iov_offset;
 441
 442			num_pages = calc_pages_for((unsigned long)data, len);
 443			pages = ceph_get_direct_page_vector(data,
 444							    num_pages, true);
 445			if (IS_ERR(pages))
 446				return PTR_ERR(pages);
 447
 448			ret = striped_read(inode, off, len,
 449					   pages, num_pages, checkeof,
 450					   1, (unsigned long)data & ~PAGE_MASK);
 451			ceph_put_page_vector(pages, num_pages, true);
 452
 453			if (ret <= 0)
 454				break;
 
 
 455			off += ret;
 456			iov_iter_advance(i, ret);
 457			if (ret < len)
 458				break;
 459		}
 
 460	} else {
 461		num_pages = calc_pages_for(off, len);
 462		pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
 463		if (IS_ERR(pages))
 464			return PTR_ERR(pages);
 465		ret = striped_read(inode, off, len, pages,
 466					num_pages, checkeof, 0, 0);
 
 467		if (ret > 0) {
 468			int l, k = 0;
 469			size_t left = len = ret;
 470
 471			while (left) {
 472				void __user *data = i->iov[0].iov_base
 473							+ i->iov_offset;
 474				l = min(i->iov[0].iov_len - i->iov_offset,
 475					left);
 476
 477				ret = ceph_copy_page_vector_to_user(&pages[k],
 478								    data, off,
 479								    l);
 480				if (ret > 0) {
 481					iov_iter_advance(i, ret);
 482					left -= ret;
 483					off += ret;
 484					k = calc_pages_for(iocb->ki_pos,
 485							   len - left + 1) - 1;
 486					BUG_ON(k >= num_pages && left);
 487				} else
 488					break;
 489			}
 490		}
 491		ceph_release_page_vector(pages, num_pages);
 492	}
 493
 494	if (off > iocb->ki_pos) {
 495		ret = off - iocb->ki_pos;
 496		iocb->ki_pos = off;
 497	}
 498
 499	dout("sync_read result %d\n", ret);
 500	return ret;
 501}
 502
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 503/*
 504 * Write commit request unsafe callback, called to tell us when a
 505 * request is unsafe (that is, in flight--has been handed to the
 506 * messenger to send to its target osd).  It is called again when
 507 * we've received a response message indicating the request is
 508 * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
 509 * is completed early (and unsuccessfully) due to a timeout or
 510 * interrupt.
 511 *
 512 * This is used if we requested both an ACK and ONDISK commit reply
 513 * from the OSD.
 514 */
 515static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
 516{
 517	struct ceph_inode_info *ci = ceph_inode(req->r_inode);
 518
 519	dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
 520		unsafe ? "un" : "");
 521	if (unsafe) {
 522		ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
 523		spin_lock(&ci->i_unsafe_lock);
 524		list_add_tail(&req->r_unsafe_item,
 525			      &ci->i_unsafe_writes);
 526		spin_unlock(&ci->i_unsafe_lock);
 
 
 527	} else {
 528		spin_lock(&ci->i_unsafe_lock);
 529		list_del_init(&req->r_unsafe_item);
 530		spin_unlock(&ci->i_unsafe_lock);
 531		ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
 532	}
 533}
 534
 535
 536/*
 537 * Synchronous write, straight from __user pointer or user pages.
 538 *
 539 * If write spans object boundary, just do multiple writes.  (For a
 540 * correct atomic write, we should e.g. take write locks on all
 541 * objects, rollback on failure, etc.)
 542 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 543static ssize_t
 544ceph_sync_direct_write(struct kiocb *iocb, const struct iovec *iov,
 545		       unsigned long nr_segs, size_t count)
 
 546{
 547	struct file *file = iocb->ki_filp;
 548	struct inode *inode = file_inode(file);
 549	struct ceph_inode_info *ci = ceph_inode(inode);
 550	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 551	struct ceph_snap_context *snapc;
 552	struct ceph_vino vino;
 553	struct ceph_osd_request *req;
 554	struct page **pages;
 555	int num_pages;
 556	int written = 0;
 557	int flags;
 558	int check_caps = 0;
 559	int page_align;
 560	int ret;
 561	struct timespec mtime = CURRENT_TIME;
 
 562	loff_t pos = iocb->ki_pos;
 563	struct iov_iter i;
 564
 565	if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
 566		return -EROFS;
 567
 568	dout("sync_direct_write on file %p %lld~%u\n", file, pos,
 569	     (unsigned)count);
 570
 571	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
 572	if (ret < 0)
 573		return ret;
 574
 575	ret = invalidate_inode_pages2_range(inode->i_mapping,
 576					    pos >> PAGE_CACHE_SHIFT,
 577					    (pos + count) >> PAGE_CACHE_SHIFT);
 578	if (ret < 0)
 579		dout("invalidate_inode_pages2_range returned %d\n", ret);
 580
 581	flags = CEPH_OSD_FLAG_ORDERSNAP |
 582		CEPH_OSD_FLAG_ONDISK |
 583		CEPH_OSD_FLAG_WRITE;
 584
 585	iov_iter_init(&i, iov, nr_segs, count, 0);
 586
 587	while (iov_iter_count(&i) > 0) {
 588		void __user *data = i.iov->iov_base + i.iov_offset;
 589		u64 len = i.iov->iov_len - i.iov_offset;
 590
 591		page_align = (unsigned long)data & ~PAGE_MASK;
 
 
 
 592
 593		snapc = ci->i_snap_realm->cached_context;
 594		vino = ceph_vino(inode);
 595		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
 596					    vino, pos, &len,
 597					    2,/*include a 'startsync' command*/
 598					    CEPH_OSD_OP_WRITE, flags, snapc,
 
 
 
 599					    ci->i_truncate_seq,
 600					    ci->i_truncate_size,
 601					    false);
 602		if (IS_ERR(req)) {
 603			ret = PTR_ERR(req);
 604			break;
 605		}
 606
 607		num_pages = calc_pages_for(page_align, len);
 608		pages = ceph_get_direct_page_vector(data, num_pages, false);
 609		if (IS_ERR(pages)) {
 
 610			ret = PTR_ERR(pages);
 611			goto out;
 612		}
 613
 614		/*
 615		 * throw out any page cache pages in this range. this
 616		 * may block.
 617		 */
 618		truncate_inode_pages_range(inode->i_mapping, pos,
 619				   (pos+len) | (PAGE_CACHE_SIZE-1));
 620		osd_req_op_extent_osd_data_pages(req, 0, pages, len, page_align,
 621						false, false);
 
 
 
 
 
 
 
 
 
 
 622
 623		/* BUG_ON(vino.snap != CEPH_NOSNAP); */
 624		ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
 
 
 
 
 
 625
 626		ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 627		if (!ret)
 628			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
 629
 630		ceph_put_page_vector(pages, num_pages, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 631
 632out:
 633		ceph_osdc_put_request(req);
 634		if (ret == 0) {
 635			pos += len;
 636			written += len;
 637			iov_iter_advance(&i, (size_t)len);
 638
 639			if (pos > i_size_read(inode)) {
 640				check_caps = ceph_inode_set_size(inode, pos);
 641				if (check_caps)
 642					ceph_check_caps(ceph_inode(inode),
 643							CHECK_CAPS_AUTHONLY,
 644							NULL);
 645			}
 646		} else
 647			break;
 
 
 
 
 
 
 
 648	}
 649
 650	if (ret != -EOLDSNAPC && written > 0) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 651		iocb->ki_pos = pos;
 652		ret = written;
 653	}
 654	return ret;
 655}
 656
 657
 658/*
 659 * Synchronous write, straight from __user pointer or user pages.
 660 *
 661 * If write spans object boundary, just do multiple writes.  (For a
 662 * correct atomic write, we should e.g. take write locks on all
 663 * objects, rollback on failure, etc.)
 664 */
 665static ssize_t ceph_sync_write(struct kiocb *iocb, const struct iovec *iov,
 666			       unsigned long nr_segs, size_t count)
 
 667{
 668	struct file *file = iocb->ki_filp;
 669	struct inode *inode = file_inode(file);
 670	struct ceph_inode_info *ci = ceph_inode(inode);
 671	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 672	struct ceph_snap_context *snapc;
 673	struct ceph_vino vino;
 674	struct ceph_osd_request *req;
 675	struct page **pages;
 676	u64 len;
 677	int num_pages;
 678	int written = 0;
 679	int flags;
 680	int check_caps = 0;
 681	int ret;
 682	struct timespec mtime = CURRENT_TIME;
 683	loff_t pos = iocb->ki_pos;
 684	struct iov_iter i;
 685
 686	if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
 687		return -EROFS;
 688
 689	dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
 690
 691	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
 692	if (ret < 0)
 693		return ret;
 694
 695	ret = invalidate_inode_pages2_range(inode->i_mapping,
 696					    pos >> PAGE_CACHE_SHIFT,
 697					    (pos + count) >> PAGE_CACHE_SHIFT);
 698	if (ret < 0)
 699		dout("invalidate_inode_pages2_range returned %d\n", ret);
 700
 701	flags = CEPH_OSD_FLAG_ORDERSNAP |
 702		CEPH_OSD_FLAG_ONDISK |
 703		CEPH_OSD_FLAG_WRITE |
 704		CEPH_OSD_FLAG_ACK;
 705
 706	iov_iter_init(&i, iov, nr_segs, count, 0);
 707
 708	while ((len = iov_iter_count(&i)) > 0) {
 709		size_t left;
 710		int n;
 711
 712		snapc = ci->i_snap_realm->cached_context;
 713		vino = ceph_vino(inode);
 714		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
 715					    vino, pos, &len, 1,
 716					    CEPH_OSD_OP_WRITE, flags, snapc,
 717					    ci->i_truncate_seq,
 718					    ci->i_truncate_size,
 719					    false);
 720		if (IS_ERR(req)) {
 721			ret = PTR_ERR(req);
 722			break;
 723		}
 724
 725		/*
 726		 * write from beginning of first page,
 727		 * regardless of io alignment
 728		 */
 729		num_pages = (len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 730
 731		pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
 732		if (IS_ERR(pages)) {
 733			ret = PTR_ERR(pages);
 734			goto out;
 735		}
 736
 737		left = len;
 738		for (n = 0; n < num_pages; n++) {
 739			size_t plen = min_t(size_t, left, PAGE_SIZE);
 740			ret = iov_iter_copy_from_user(pages[n], &i, 0, plen);
 741			if (ret != plen) {
 742				ret = -EFAULT;
 743				break;
 744			}
 745			left -= ret;
 746			iov_iter_advance(&i, ret);
 747		}
 748
 749		if (ret < 0) {
 750			ceph_release_page_vector(pages, num_pages);
 751			goto out;
 752		}
 753
 754		/* get a second commit callback */
 755		req->r_unsafe_callback = ceph_sync_write_unsafe;
 756		req->r_inode = inode;
 757
 758		osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
 759						false, true);
 760
 761		/* BUG_ON(vino.snap != CEPH_NOSNAP); */
 762		ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
 763
 764		ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
 765		if (!ret)
 766			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
 767
 768out:
 769		ceph_osdc_put_request(req);
 770		if (ret == 0) {
 771			pos += len;
 772			written += len;
 773
 774			if (pos > i_size_read(inode)) {
 775				check_caps = ceph_inode_set_size(inode, pos);
 776				if (check_caps)
 777					ceph_check_caps(ceph_inode(inode),
 778							CHECK_CAPS_AUTHONLY,
 779							NULL);
 780			}
 781		} else
 782			break;
 783	}
 784
 785	if (ret != -EOLDSNAPC && written > 0) {
 786		ret = written;
 787		iocb->ki_pos = pos;
 788	}
 789	return ret;
 790}
 791
 792/*
 793 * Wrap generic_file_aio_read with checks for cap bits on the inode.
 794 * Atomically grab references, so that those bits are not released
 795 * back to the MDS mid-read.
 796 *
 797 * Hmm, the sync read case isn't actually async... should it be?
 798 */
 799static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov,
 800			     unsigned long nr_segs, loff_t pos)
 801{
 802	struct file *filp = iocb->ki_filp;
 803	struct ceph_file_info *fi = filp->private_data;
 804	size_t len = iocb->ki_nbytes;
 805	struct inode *inode = file_inode(filp);
 806	struct ceph_inode_info *ci = ceph_inode(inode);
 
 807	ssize_t ret;
 808	int want, got = 0;
 809	int checkeof = 0, read = 0;
 810
 811again:
 812	dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
 813	     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
 814
 815	if (fi->fmode & CEPH_FILE_MODE_LAZY)
 816		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
 817	else
 818		want = CEPH_CAP_FILE_CACHE;
 819	ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1);
 820	if (ret < 0)
 821		return ret;
 822
 823	if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
 824	    (iocb->ki_filp->f_flags & O_DIRECT) ||
 825	    (fi->flags & CEPH_F_SYNC)) {
 826		struct iov_iter i;
 827
 828		dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
 829		     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
 830		     ceph_cap_string(got));
 831
 832		if (!read) {
 833			ret = generic_segment_checks(iov, &nr_segs,
 834							&len, VERIFY_WRITE);
 835			if (ret)
 836				goto out;
 
 
 
 
 
 
 837		}
 838
 839		iov_iter_init(&i, iov, nr_segs, len, read);
 840
 841		/* hmm, this isn't really async... */
 842		ret = ceph_sync_read(iocb, &i, &checkeof);
 843	} else {
 844		/*
 845		 * We can't modify the content of iov,
 846		 * so we only read from beginning.
 847		 */
 848		if (read) {
 849			iocb->ki_pos = pos;
 850			len = iocb->ki_nbytes;
 851			read = 0;
 852		}
 853		dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
 854		     inode, ceph_vinop(inode), pos, (unsigned)len,
 855		     ceph_cap_string(got));
 856
 857		ret = generic_file_aio_read(iocb, iov, nr_segs, pos);
 
 858	}
 859out:
 860	dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
 861	     inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
 
 
 
 
 862	ceph_put_cap_refs(ci, got);
 
 
 
 
 
 
 
 
 
 863
 864	if (checkeof && ret >= 0) {
 865		int statret = ceph_do_getattr(inode,
 866					      CEPH_STAT_CAP_SIZE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 867
 868		/* hit EOF or hole? */
 869		if (statret == 0 && iocb->ki_pos < inode->i_size &&
 870			ret < len) {
 871			dout("sync_read hit hole, ppos %lld < size %lld"
 872			     ", reading more\n", iocb->ki_pos,
 873			     inode->i_size);
 874
 875			read += ret;
 876			len -= ret;
 877			checkeof = 0;
 878			goto again;
 879		}
 880	}
 881
 882	if (ret >= 0)
 883		ret += read;
 884
 885	return ret;
 886}
 887
 888/*
 889 * Take cap references to avoid releasing caps to MDS mid-write.
 890 *
 891 * If we are synchronous, and write with an old snap context, the OSD
 892 * may return EOLDSNAPC.  In that case, retry the write.. _after_
 893 * dropping our cap refs and allowing the pending snap to logically
 894 * complete _before_ this write occurs.
 895 *
 896 * If we are near ENOSPC, write synchronously.
 897 */
 898static ssize_t ceph_aio_write(struct kiocb *iocb, const struct iovec *iov,
 899		       unsigned long nr_segs, loff_t pos)
 900{
 901	struct file *file = iocb->ki_filp;
 902	struct ceph_file_info *fi = file->private_data;
 903	struct inode *inode = file_inode(file);
 904	struct ceph_inode_info *ci = ceph_inode(inode);
 905	struct ceph_osd_client *osdc =
 906		&ceph_sb_to_client(inode->i_sb)->client->osdc;
 
 907	ssize_t count, written = 0;
 908	int err, want, got;
 
 909
 910	if (ceph_snap(inode) != CEPH_NOSNAP)
 911		return -EROFS;
 912
 913	mutex_lock(&inode->i_mutex);
 
 
 914
 915	err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ);
 916	if (err)
 917		goto out;
 918
 919	/* We can write back this queue in page reclaim */
 920	current->backing_dev_info = file->f_mapping->backing_dev_info;
 921
 922	err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
 923	if (err)
 924		goto out;
 
 
 925
 926	if (count == 0)
 
 927		goto out;
 928
 929	err = file_remove_suid(file);
 
 
 930	if (err)
 931		goto out;
 932
 933	err = file_update_time(file);
 934	if (err)
 935		goto out;
 936
 
 
 
 
 
 
 937retry_snap:
 938	if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
 939		err = -ENOSPC;
 940		goto out;
 941	}
 942
 943	dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
 944	     inode, ceph_vinop(inode), pos, count, inode->i_size);
 945	if (fi->fmode & CEPH_FILE_MODE_LAZY)
 946		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
 947	else
 948		want = CEPH_CAP_FILE_BUFFER;
 949	got = 0;
 950	err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, pos + count);
 
 951	if (err < 0)
 952		goto out;
 953
 954	dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
 955	     inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
 956
 957	if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
 958	    (file->f_flags & O_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
 959		mutex_unlock(&inode->i_mutex);
 960		if (file->f_flags & O_DIRECT)
 961			written = ceph_sync_direct_write(iocb, iov,
 962							 nr_segs, count);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 963		else
 964			written = ceph_sync_write(iocb, iov, nr_segs, count);
 965		if (written == -EOLDSNAPC) {
 966			dout("aio_write %p %llx.%llx %llu~%u"
 967				"got EOLDSNAPC, retrying\n",
 968				inode, ceph_vinop(inode),
 969				pos, (unsigned)iov->iov_len);
 970			mutex_lock(&inode->i_mutex);
 971			goto retry_snap;
 972		}
 
 
 
 973	} else {
 974		loff_t old_size = inode->i_size;
 975		struct iov_iter from;
 976		/*
 977		 * No need to acquire the i_truncate_mutex. Because
 978		 * the MDS revokes Fwb caps before sending truncate
 979		 * message to us. We can't get Fwb cap while there
 980		 * are pending vmtruncate. So write and vmtruncate
 981		 * can not run at the same time
 982		 */
 983		iov_iter_init(&from, iov, nr_segs, count, 0);
 984		written = generic_perform_write(file, &from, pos);
 985		if (likely(written >= 0))
 986			iocb->ki_pos = pos + written;
 987		if (inode->i_size > old_size)
 988			ceph_fscache_update_objectsize(inode);
 989		mutex_unlock(&inode->i_mutex);
 990	}
 991
 992	if (written >= 0) {
 993		int dirty;
 994		spin_lock(&ci->i_ceph_lock);
 995		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
 
 
 996		spin_unlock(&ci->i_ceph_lock);
 997		if (dirty)
 998			__mark_inode_dirty(inode, dirty);
 999	}
1000
1001	dout("aio_write %p %llx.%llx %llu~%u  dropping cap refs on %s\n",
1002	     inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len,
1003	     ceph_cap_string(got));
1004	ceph_put_cap_refs(ci, got);
1005
1006	if (written >= 0 &&
1007	    ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
1008	     ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
1009		err = vfs_fsync_range(file, pos, pos + written - 1, 1);
1010		if (err < 0)
1011			written = err;
1012	}
1013
1014	goto out_unlocked;
1015
1016out:
1017	mutex_unlock(&inode->i_mutex);
1018out_unlocked:
 
1019	current->backing_dev_info = NULL;
1020	return written ? written : err;
1021}
1022
1023/*
1024 * llseek.  be sure to verify file size on SEEK_END.
1025 */
1026static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
1027{
1028	struct inode *inode = file->f_mapping->host;
1029	int ret;
 
1030
1031	mutex_lock(&inode->i_mutex);
1032
1033	if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
1034		ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);
1035		if (ret < 0) {
1036			offset = ret;
1037			goto out;
1038		}
1039	}
1040
 
1041	switch (whence) {
1042	case SEEK_END:
1043		offset += inode->i_size;
1044		break;
1045	case SEEK_CUR:
1046		/*
1047		 * Here we special-case the lseek(fd, 0, SEEK_CUR)
1048		 * position-querying operation.  Avoid rewriting the "same"
1049		 * f_pos value back to the file because a concurrent read(),
1050		 * write() or lseek() might have altered it
1051		 */
1052		if (offset == 0) {
1053			offset = file->f_pos;
1054			goto out;
1055		}
1056		offset += file->f_pos;
1057		break;
1058	case SEEK_DATA:
1059		if (offset >= inode->i_size) {
1060			ret = -ENXIO;
1061			goto out;
1062		}
1063		break;
1064	case SEEK_HOLE:
1065		if (offset >= inode->i_size) {
1066			ret = -ENXIO;
1067			goto out;
1068		}
1069		offset = inode->i_size;
1070		break;
1071	}
1072
1073	offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1074
1075out:
1076	mutex_unlock(&inode->i_mutex);
1077	return offset;
1078}
1079
1080static inline void ceph_zero_partial_page(
1081	struct inode *inode, loff_t offset, unsigned size)
1082{
1083	struct page *page;
1084	pgoff_t index = offset >> PAGE_CACHE_SHIFT;
1085
1086	page = find_lock_page(inode->i_mapping, index);
1087	if (page) {
1088		wait_on_page_writeback(page);
1089		zero_user(page, offset & (PAGE_CACHE_SIZE - 1), size);
1090		unlock_page(page);
1091		page_cache_release(page);
1092	}
1093}
1094
1095static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1096				      loff_t length)
1097{
1098	loff_t nearly = round_up(offset, PAGE_CACHE_SIZE);
1099	if (offset < nearly) {
1100		loff_t size = nearly - offset;
1101		if (length < size)
1102			size = length;
1103		ceph_zero_partial_page(inode, offset, size);
1104		offset += size;
1105		length -= size;
1106	}
1107	if (length >= PAGE_CACHE_SIZE) {
1108		loff_t size = round_down(length, PAGE_CACHE_SIZE);
1109		truncate_pagecache_range(inode, offset, offset + size - 1);
1110		offset += size;
1111		length -= size;
1112	}
1113	if (length)
1114		ceph_zero_partial_page(inode, offset, length);
1115}
1116
1117static int ceph_zero_partial_object(struct inode *inode,
1118				    loff_t offset, loff_t *length)
1119{
1120	struct ceph_inode_info *ci = ceph_inode(inode);
1121	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1122	struct ceph_osd_request *req;
1123	int ret = 0;
1124	loff_t zero = 0;
1125	int op;
1126
1127	if (!length) {
1128		op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1129		length = &zero;
1130	} else {
1131		op = CEPH_OSD_OP_ZERO;
1132	}
1133
1134	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1135					ceph_vino(inode),
1136					offset, length,
1137					1, op,
1138					CEPH_OSD_FLAG_WRITE |
1139					CEPH_OSD_FLAG_ONDISK,
1140					NULL, 0, 0, false);
1141	if (IS_ERR(req)) {
1142		ret = PTR_ERR(req);
1143		goto out;
1144	}
1145
1146	ceph_osdc_build_request(req, offset, NULL, ceph_vino(inode).snap,
1147				&inode->i_mtime);
1148
1149	ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1150	if (!ret) {
1151		ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1152		if (ret == -ENOENT)
1153			ret = 0;
1154	}
1155	ceph_osdc_put_request(req);
1156
1157out:
1158	return ret;
1159}
1160
1161static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1162{
1163	int ret = 0;
1164	struct ceph_inode_info *ci = ceph_inode(inode);
1165	s32 stripe_unit = ceph_file_layout_su(ci->i_layout);
1166	s32 stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
1167	s32 object_size = ceph_file_layout_object_size(ci->i_layout);
1168	u64 object_set_size = object_size * stripe_count;
1169	u64 nearly, t;
1170
1171	/* round offset up to next period boundary */
1172	nearly = offset + object_set_size - 1;
1173	t = nearly;
1174	nearly -= do_div(t, object_set_size);
1175
1176	while (length && offset < nearly) {
1177		loff_t size = length;
1178		ret = ceph_zero_partial_object(inode, offset, &size);
1179		if (ret < 0)
1180			return ret;
1181		offset += size;
1182		length -= size;
1183	}
1184	while (length >= object_set_size) {
1185		int i;
1186		loff_t pos = offset;
1187		for (i = 0; i < stripe_count; ++i) {
1188			ret = ceph_zero_partial_object(inode, pos, NULL);
1189			if (ret < 0)
1190				return ret;
1191			pos += stripe_unit;
1192		}
1193		offset += object_set_size;
1194		length -= object_set_size;
1195	}
1196	while (length) {
1197		loff_t size = length;
1198		ret = ceph_zero_partial_object(inode, offset, &size);
1199		if (ret < 0)
1200			return ret;
1201		offset += size;
1202		length -= size;
1203	}
1204	return ret;
1205}
1206
1207static long ceph_fallocate(struct file *file, int mode,
1208				loff_t offset, loff_t length)
1209{
1210	struct ceph_file_info *fi = file->private_data;
1211	struct inode *inode = file_inode(file);
1212	struct ceph_inode_info *ci = ceph_inode(inode);
1213	struct ceph_osd_client *osdc =
1214		&ceph_inode_to_client(inode)->client->osdc;
 
1215	int want, got = 0;
1216	int dirty;
1217	int ret = 0;
1218	loff_t endoff = 0;
1219	loff_t size;
1220
 
 
 
1221	if (!S_ISREG(inode->i_mode))
1222		return -EOPNOTSUPP;
1223
1224	mutex_lock(&inode->i_mutex);
 
 
 
 
1225
1226	if (ceph_snap(inode) != CEPH_NOSNAP) {
1227		ret = -EROFS;
1228		goto unlock;
1229	}
1230
1231	if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) &&
1232		!(mode & FALLOC_FL_PUNCH_HOLE)) {
1233		ret = -ENOSPC;
1234		goto unlock;
1235	}
1236
 
 
 
 
 
 
1237	size = i_size_read(inode);
1238	if (!(mode & FALLOC_FL_KEEP_SIZE))
1239		endoff = offset + length;
1240
1241	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1242		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1243	else
1244		want = CEPH_CAP_FILE_BUFFER;
1245
1246	ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, endoff);
1247	if (ret < 0)
1248		goto unlock;
1249
1250	if (mode & FALLOC_FL_PUNCH_HOLE) {
1251		if (offset < size)
1252			ceph_zero_pagecache_range(inode, offset, length);
1253		ret = ceph_zero_objects(inode, offset, length);
1254	} else if (endoff > size) {
1255		truncate_pagecache_range(inode, size, -1);
1256		if (ceph_inode_set_size(inode, endoff))
1257			ceph_check_caps(ceph_inode(inode),
1258				CHECK_CAPS_AUTHONLY, NULL);
1259	}
1260
1261	if (!ret) {
1262		spin_lock(&ci->i_ceph_lock);
1263		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
 
 
1264		spin_unlock(&ci->i_ceph_lock);
1265		if (dirty)
1266			__mark_inode_dirty(inode, dirty);
1267	}
1268
1269	ceph_put_cap_refs(ci, got);
1270unlock:
1271	mutex_unlock(&inode->i_mutex);
 
1272	return ret;
1273}
1274
1275const struct file_operations ceph_file_fops = {
1276	.open = ceph_open,
1277	.release = ceph_release,
1278	.llseek = ceph_llseek,
1279	.read = do_sync_read,
1280	.write = do_sync_write,
1281	.aio_read = ceph_aio_read,
1282	.aio_write = ceph_aio_write,
1283	.mmap = ceph_mmap,
1284	.fsync = ceph_fsync,
1285	.lock = ceph_lock,
1286	.flock = ceph_flock,
1287	.splice_read = generic_file_splice_read,
1288	.splice_write = generic_file_splice_write,
1289	.unlocked_ioctl = ceph_ioctl,
1290	.compat_ioctl	= ceph_ioctl,
1291	.fallocate	= ceph_fallocate,
1292};
1293
   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