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v3.1
 
  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/namei.h>
  8#include <linux/writeback.h>
 
  9
 10#include "super.h"
 11#include "mds_client.h"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 12
 13/*
 14 * Ceph file operations
 15 *
 16 * Implement basic open/close functionality, and implement
 17 * read/write.
 18 *
 19 * We implement three modes of file I/O:
 20 *  - buffered uses the generic_file_aio_{read,write} helpers
 21 *
 22 *  - synchronous is used when there is multi-client read/write
 23 *    sharing, avoids the page cache, and synchronously waits for an
 24 *    ack from the OSD.
 25 *
 26 *  - direct io takes the variant of the sync path that references
 27 *    user pages directly.
 28 *
 29 * fsync() flushes and waits on dirty pages, but just queues metadata
 30 * for writeback: since the MDS can recover size and mtime there is no
 31 * need to wait for MDS acknowledgement.
 32 */
 33
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 34
 35/*
 36 * Prepare an open request.  Preallocate ceph_cap to avoid an
 37 * inopportune ENOMEM later.
 38 */
 39static struct ceph_mds_request *
 40prepare_open_request(struct super_block *sb, int flags, int create_mode)
 41{
 42	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 43	struct ceph_mds_client *mdsc = fsc->mdsc;
 44	struct ceph_mds_request *req;
 45	int want_auth = USE_ANY_MDS;
 46	int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
 47
 48	if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
 49		want_auth = USE_AUTH_MDS;
 50
 51	req = ceph_mdsc_create_request(mdsc, op, want_auth);
 52	if (IS_ERR(req))
 53		goto out;
 54	req->r_fmode = ceph_flags_to_mode(flags);
 55	req->r_args.open.flags = cpu_to_le32(flags);
 56	req->r_args.open.mode = cpu_to_le32(create_mode);
 57	req->r_args.open.preferred = cpu_to_le32(-1);
 58out:
 59	return req;
 60}
 61
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 62/*
 63 * initialize private struct file data.
 64 * if we fail, clean up by dropping fmode reference on the ceph_inode
 65 */
 66static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
 67{
 68	struct ceph_file_info *cf;
 69	int ret = 0;
 70
 71	switch (inode->i_mode & S_IFMT) {
 72	case S_IFREG:
 
 
 73	case S_IFDIR:
 74		dout("init_file %p %p 0%o (regular)\n", inode, file,
 75		     inode->i_mode);
 76		cf = kmem_cache_alloc(ceph_file_cachep, GFP_NOFS | __GFP_ZERO);
 77		if (cf == NULL) {
 78			ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 79			return -ENOMEM;
 80		}
 81		cf->fmode = fmode;
 82		cf->next_offset = 2;
 83		file->private_data = cf;
 84		BUG_ON(inode->i_fop->release != ceph_release);
 85		break;
 86
 87	case S_IFLNK:
 88		dout("init_file %p %p 0%o (symlink)\n", inode, file,
 89		     inode->i_mode);
 90		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 91		break;
 92
 93	default:
 94		dout("init_file %p %p 0%o (special)\n", inode, file,
 95		     inode->i_mode);
 96		/*
 97		 * we need to drop the open ref now, since we don't
 98		 * have .release set to ceph_release.
 99		 */
100		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
101		BUG_ON(inode->i_fop->release == ceph_release);
102
103		/* call the proper open fop */
104		ret = inode->i_fop->open(inode, file);
105	}
106	return ret;
107}
108
109/*
110 * If the filp already has private_data, that means the file was
111 * already opened by intent during lookup, and we do nothing.
112 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
113 * If we already have the requisite capabilities, we can satisfy
114 * the open request locally (no need to request new caps from the
115 * MDS).  We do, however, need to inform the MDS (asynchronously)
116 * if our wanted caps set expands.
117 */
118int ceph_open(struct inode *inode, struct file *file)
119{
120	struct ceph_inode_info *ci = ceph_inode(inode);
121	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
122	struct ceph_mds_client *mdsc = fsc->mdsc;
123	struct ceph_mds_request *req;
124	struct ceph_file_info *cf = file->private_data;
125	struct inode *parent_inode = NULL;
126	int err;
127	int flags, fmode, wanted;
128
129	if (cf) {
130		dout("open file %p is already opened\n", file);
131		return 0;
132	}
133
134	/* filter out O_CREAT|O_EXCL; vfs did that already.  yuck. */
135	flags = file->f_flags & ~(O_CREAT|O_EXCL);
136	if (S_ISDIR(inode->i_mode))
137		flags = O_DIRECTORY;  /* mds likes to know */
138
139	dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
140	     ceph_vinop(inode), file, flags, file->f_flags);
141	fmode = ceph_flags_to_mode(flags);
142	wanted = ceph_caps_for_mode(fmode);
143
144	/* snapped files are read-only */
145	if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
146		return -EROFS;
147
148	/* trivially open snapdir */
149	if (ceph_snap(inode) == CEPH_SNAPDIR) {
150		spin_lock(&inode->i_lock);
151		__ceph_get_fmode(ci, fmode);
152		spin_unlock(&inode->i_lock);
153		return ceph_init_file(inode, file, fmode);
154	}
155
156	/*
157	 * No need to block if we have caps on the auth MDS (for
158	 * write) or any MDS (for read).  Update wanted set
159	 * asynchronously.
160	 */
161	spin_lock(&inode->i_lock);
162	if (__ceph_is_any_real_caps(ci) &&
163	    (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
164		int mds_wanted = __ceph_caps_mds_wanted(ci);
165		int issued = __ceph_caps_issued(ci, NULL);
166
167		dout("open %p fmode %d want %s issued %s using existing\n",
168		     inode, fmode, ceph_cap_string(wanted),
169		     ceph_cap_string(issued));
170		__ceph_get_fmode(ci, fmode);
171		spin_unlock(&inode->i_lock);
172
173		/* adjust wanted? */
174		if ((issued & wanted) != wanted &&
175		    (mds_wanted & wanted) != wanted &&
176		    ceph_snap(inode) != CEPH_SNAPDIR)
177			ceph_check_caps(ci, 0, NULL);
178
179		return ceph_init_file(inode, file, fmode);
180	} else if (ceph_snap(inode) != CEPH_NOSNAP &&
181		   (ci->i_snap_caps & wanted) == wanted) {
182		__ceph_get_fmode(ci, fmode);
183		spin_unlock(&inode->i_lock);
184		return ceph_init_file(inode, file, fmode);
185	}
186	spin_unlock(&inode->i_lock);
 
187
188	dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
189	req = prepare_open_request(inode->i_sb, flags, 0);
190	if (IS_ERR(req)) {
191		err = PTR_ERR(req);
192		goto out;
193	}
194	req->r_inode = inode;
195	ihold(inode);
 
196	req->r_num_caps = 1;
197	if (flags & (O_CREAT|O_TRUNC))
198		parent_inode = ceph_get_dentry_parent_inode(file->f_dentry);
199	err = ceph_mdsc_do_request(mdsc, parent_inode, req);
200	iput(parent_inode);
201	if (!err)
202		err = ceph_init_file(inode, file, req->r_fmode);
203	ceph_mdsc_put_request(req);
204	dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
205out:
206	return err;
207}
208
209
210/*
211 * Do a lookup + open with a single request.
212 *
213 * If this succeeds, but some subsequent check in the vfs
214 * may_open() fails, the struct *file gets cleaned up (i.e.
215 * ceph_release gets called).  So fear not!
216 */
217/*
218 * flags
219 *  path_lookup_open   -> LOOKUP_OPEN
220 *  path_lookup_create -> LOOKUP_OPEN|LOOKUP_CREATE
221 */
222struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
223				struct nameidata *nd, int mode,
224				int locked_dir)
225{
226	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
227	struct ceph_mds_client *mdsc = fsc->mdsc;
228	struct file *file;
229	struct ceph_mds_request *req;
230	struct dentry *ret;
 
 
231	int err;
232	int flags = nd->intent.open.flags;
233
234	dout("ceph_lookup_open dentry %p '%.*s' flags %d mode 0%o\n",
235	     dentry, dentry->d_name.len, dentry->d_name.name, flags, mode);
 
 
 
 
 
 
 
 
 
 
 
 
236
237	/* do the open */
238	req = prepare_open_request(dir->i_sb, flags, mode);
239	if (IS_ERR(req))
240		return ERR_CAST(req);
 
 
241	req->r_dentry = dget(dentry);
242	req->r_num_caps = 2;
243	if (flags & O_CREAT) {
244		req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
245		req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 
 
 
 
246	}
247	req->r_locked_dir = dir;           /* caller holds dir->i_mutex */
 
 
 
 
 
 
 
248	err = ceph_mdsc_do_request(mdsc,
249				   (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
250				   req);
251	err = ceph_handle_snapdir(req, dentry, err);
252	if (err)
253		goto out;
 
254	if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
255		err = ceph_handle_notrace_create(dir, dentry);
 
 
 
 
 
 
 
 
 
256	if (err)
257		goto out;
258	file = lookup_instantiate_filp(nd, req->r_dentry, ceph_open);
259	if (IS_ERR(file))
260		err = PTR_ERR(file);
261out:
262	ret = ceph_finish_lookup(req, dentry, err);
 
 
 
 
 
 
 
 
 
 
263	ceph_mdsc_put_request(req);
264	dout("ceph_lookup_open result=%p\n", ret);
265	return ret;
 
 
266}
267
268int ceph_release(struct inode *inode, struct file *file)
269{
270	struct ceph_inode_info *ci = ceph_inode(inode);
271	struct ceph_file_info *cf = file->private_data;
272
273	dout("release inode %p file %p\n", inode, file);
274	ceph_put_fmode(ci, cf->fmode);
275	if (cf->last_readdir)
276		ceph_mdsc_put_request(cf->last_readdir);
277	kfree(cf->last_name);
278	kfree(cf->dir_info);
279	dput(cf->dentry);
280	kmem_cache_free(ceph_file_cachep, cf);
 
 
 
 
 
 
 
 
 
 
 
 
281
282	/* wake up anyone waiting for caps on this inode */
283	wake_up_all(&ci->i_cap_wq);
284	return 0;
285}
286
 
 
 
 
 
 
287/*
288 * Read a range of bytes striped over one or more objects.  Iterate over
289 * objects we stripe over.  (That's not atomic, but good enough for now.)
290 *
291 * If we get a short result from the OSD, check against i_size; we need to
292 * only return a short read to the caller if we hit EOF.
293 */
294static int striped_read(struct inode *inode,
295			u64 off, u64 len,
296			struct page **pages, int num_pages,
297			int *checkeof, bool o_direct,
298			unsigned long buf_align)
299{
300	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
301	struct ceph_inode_info *ci = ceph_inode(inode);
302	u64 pos, this_len;
303	int io_align, page_align;
304	int left, pages_left;
305	int read;
306	struct page **page_pos;
307	int ret;
308	bool hit_stripe, was_short;
309
310	/*
311	 * we may need to do multiple reads.  not atomic, unfortunately.
312	 */
313	pos = off;
314	left = len;
315	page_pos = pages;
316	pages_left = num_pages;
317	read = 0;
318	io_align = off & ~PAGE_MASK;
319
320more:
321	if (o_direct)
322		page_align = (pos - io_align + buf_align) & ~PAGE_MASK;
323	else
324		page_align = pos & ~PAGE_MASK;
325	this_len = left;
326	ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
327				  &ci->i_layout, pos, &this_len,
328				  ci->i_truncate_seq,
329				  ci->i_truncate_size,
330				  page_pos, pages_left, page_align);
331	if (ret == -ENOENT)
332		ret = 0;
333	hit_stripe = this_len < left;
334	was_short = ret >= 0 && ret < this_len;
335	dout("striped_read %llu~%u (read %u) got %d%s%s\n", pos, left, read,
336	     ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
337
338	if (ret > 0) {
339		int didpages = (page_align + ret) >> PAGE_CACHE_SHIFT;
340
341		if (read < pos - off) {
342			dout(" zero gap %llu to %llu\n", off + read, pos);
343			ceph_zero_page_vector_range(page_align + read,
344						    pos - off - read, pages);
 
 
345		}
 
 
346		pos += ret;
347		read = pos - off;
348		left -= ret;
349		page_pos += didpages;
350		pages_left -= didpages;
351
352		/* hit stripe? */
353		if (left && hit_stripe)
354			goto more;
355	}
356
357	if (was_short) {
 
358		/* did we bounce off eof? */
359		if (pos + left > inode->i_size)
360			*checkeof = 1;
361
362		/* zero trailing bytes (inside i_size) */
363		if (left > 0 && pos < inode->i_size) {
364			if (pos + left > inode->i_size)
365				left = inode->i_size - pos;
366
367			dout("zero tail %d\n", left);
368			ceph_zero_page_vector_range(page_align + read, left,
369						    pages);
370			read += left;
371		}
372	}
373
374	if (ret >= 0)
375		ret = read;
376	dout("striped_read returns %d\n", ret);
377	return ret;
378}
379
380/*
381 * Completely synchronous read and write methods.  Direct from __user
382 * buffer to osd, or directly to user pages (if O_DIRECT).
383 *
384 * If the read spans object boundary, just do multiple reads.
385 */
386static ssize_t ceph_sync_read(struct file *file, char __user *data,
387			      unsigned len, loff_t *poff, int *checkeof)
388{
389	struct inode *inode = file->f_dentry->d_inode;
 
390	struct page **pages;
391	u64 off = *poff;
392	int num_pages, ret;
 
 
393
394	dout("sync_read on file %p %llu~%u %s\n", file, off, len,
395	     (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
396
397	if (file->f_flags & O_DIRECT) {
398		num_pages = calc_pages_for((unsigned long)data, len);
399		pages = ceph_get_direct_page_vector(data, num_pages, true);
400	} else {
401		num_pages = calc_pages_for(off, len);
402		pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
403	}
404	if (IS_ERR(pages))
405		return PTR_ERR(pages);
406
407	/*
408	 * flush any page cache pages in this range.  this
409	 * will make concurrent normal and sync io slow,
410	 * but it will at least behave sensibly when they are
411	 * in sequence.
412	 */
413	ret = filemap_write_and_wait(inode->i_mapping);
 
414	if (ret < 0)
415		goto done;
416
417	ret = striped_read(inode, off, len, pages, num_pages, checkeof,
418			   file->f_flags & O_DIRECT,
419			   (unsigned long)data & ~PAGE_MASK);
420
421	if (ret >= 0 && (file->f_flags & O_DIRECT) == 0)
422		ret = ceph_copy_page_vector_to_user(pages, data, off, ret);
423	if (ret >= 0)
424		*poff = off + ret;
 
 
 
425
426done:
427	if (file->f_flags & O_DIRECT)
428		ceph_put_page_vector(pages, num_pages, true);
429	else
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
430		ceph_release_page_vector(pages, num_pages);
431	dout("sync_read result %d\n", ret);
 
 
 
 
 
 
 
432	return ret;
433}
434
435/*
436 * Write commit callback, called if we requested both an ACK and
437 * ONDISK commit reply from the OSD.
438 */
439static void sync_write_commit(struct ceph_osd_request *req,
440			      struct ceph_msg *msg)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
441{
442	struct ceph_inode_info *ci = ceph_inode(req->r_inode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
443
444	dout("sync_write_commit %p tid %llu\n", req, req->r_tid);
445	spin_lock(&ci->i_unsafe_lock);
446	list_del_init(&req->r_unsafe_item);
447	spin_unlock(&ci->i_unsafe_lock);
448	ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
449}
450
451/*
452 * Synchronous write, straight from __user pointer or user pages (if
453 * O_DIRECT).
454 *
455 * If write spans object boundary, just do multiple writes.  (For a
456 * correct atomic write, we should e.g. take write locks on all
457 * objects, rollback on failure, etc.)
458 */
459static ssize_t ceph_sync_write(struct file *file, const char __user *data,
460			       size_t left, loff_t *offset)
 
461{
462	struct inode *inode = file->f_dentry->d_inode;
 
463	struct ceph_inode_info *ci = ceph_inode(inode);
464	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 
465	struct ceph_osd_request *req;
466	struct page **pages;
467	int num_pages;
468	long long unsigned pos;
469	u64 len;
 
470	int written = 0;
471	int flags;
472	int do_sync = 0;
473	int check_caps = 0;
474	int page_align, io_align;
475	unsigned long buf_align;
476	int ret;
477	struct timespec mtime = CURRENT_TIME;
 
 
478
479	if (ceph_snap(file->f_dentry->d_inode) != CEPH_NOSNAP)
480		return -EROFS;
481
482	dout("sync_write on file %p %lld~%u %s\n", file, *offset,
483	     (unsigned)left, (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
484
485	if (file->f_flags & O_APPEND)
486		pos = i_size_read(inode);
487	else
488		pos = *offset;
489
490	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + left);
491	if (ret < 0)
492		return ret;
493
494	ret = invalidate_inode_pages2_range(inode->i_mapping,
495					    pos >> PAGE_CACHE_SHIFT,
496					    (pos + left) >> PAGE_CACHE_SHIFT);
497	if (ret < 0)
498		dout("invalidate_inode_pages2_range returned %d\n", ret);
499
500	flags = CEPH_OSD_FLAG_ORDERSNAP |
501		CEPH_OSD_FLAG_ONDISK |
502		CEPH_OSD_FLAG_WRITE;
503	if ((file->f_flags & (O_SYNC|O_DIRECT)) == 0)
504		flags |= CEPH_OSD_FLAG_ACK;
505	else
506		do_sync = 1;
507
508	/*
509	 * we may need to do multiple writes here if we span an object
510	 * boundary.  this isn't atomic, unfortunately.  :(
511	 */
512more:
513	io_align = pos & ~PAGE_MASK;
514	buf_align = (unsigned long)data & ~PAGE_MASK;
515	len = left;
516	if (file->f_flags & O_DIRECT) {
517		/* write from beginning of first page, regardless of
518		   io alignment */
519		page_align = (pos - io_align + buf_align) & ~PAGE_MASK;
520		num_pages = calc_pages_for((unsigned long)data, len);
521	} else {
522		page_align = pos & ~PAGE_MASK;
523		num_pages = calc_pages_for(pos, len);
524	}
525	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
526				    ceph_vino(inode), pos, &len,
527				    CEPH_OSD_OP_WRITE, flags,
528				    ci->i_snap_realm->cached_context,
529				    do_sync,
530				    ci->i_truncate_seq, ci->i_truncate_size,
531				    &mtime, false, 2, page_align);
532	if (!req)
533		return -ENOMEM;
534
535	if (file->f_flags & O_DIRECT) {
536		pages = ceph_get_direct_page_vector(data, num_pages, false);
537		if (IS_ERR(pages)) {
538			ret = PTR_ERR(pages);
539			goto out;
 
 
 
 
 
 
 
 
 
540		}
541
542		/*
543		 * throw out any page cache pages in this range. this
544		 * may block.
545		 */
546		truncate_inode_pages_range(inode->i_mapping, pos,
547					   (pos+len) | (PAGE_CACHE_SIZE-1));
548	} else {
549		pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
550		if (IS_ERR(pages)) {
551			ret = PTR_ERR(pages);
552			goto out;
553		}
554		ret = ceph_copy_user_to_page_vector(pages, data, pos, len);
 
 
 
 
 
 
 
 
 
 
 
555		if (ret < 0) {
556			ceph_release_page_vector(pages, num_pages);
557			goto out;
558		}
559
560		if ((file->f_flags & O_SYNC) == 0) {
561			/* get a second commit callback */
562			req->r_safe_callback = sync_write_commit;
563			req->r_own_pages = 1;
564		}
565	}
566	req->r_pages = pages;
567	req->r_num_pages = num_pages;
568	req->r_inode = inode;
569
570	ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
571	if (!ret) {
572		if (req->r_safe_callback) {
573			/*
574			 * Add to inode unsafe list only after we
575			 * start_request so that a tid has been assigned.
576			 */
577			spin_lock(&ci->i_unsafe_lock);
578			list_add_tail(&req->r_unsafe_item,
579				      &ci->i_unsafe_writes);
580			spin_unlock(&ci->i_unsafe_lock);
581			ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
582		}
583		
584		ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
585		if (ret < 0 && req->r_safe_callback) {
586			spin_lock(&ci->i_unsafe_lock);
587			list_del_init(&req->r_unsafe_item);
588			spin_unlock(&ci->i_unsafe_lock);
589			ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
590		}
591	}
592
593	if (file->f_flags & O_DIRECT)
594		ceph_put_page_vector(pages, num_pages, false);
595	else if (file->f_flags & O_SYNC)
596		ceph_release_page_vector(pages, num_pages);
597
598out:
599	ceph_osdc_put_request(req);
600	if (ret == 0) {
 
 
 
 
 
601		pos += len;
602		written += len;
603		left -= len;
604		data += written;
605		if (left)
606			goto more;
 
 
 
 
 
607
 
608		ret = written;
609		*offset = pos;
610		if (pos > i_size_read(inode))
611			check_caps = ceph_inode_set_size(inode, pos);
612		if (check_caps)
613			ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY,
614					NULL);
615	}
616	return ret;
617}
618
619/*
620 * Wrap generic_file_aio_read with checks for cap bits on the inode.
621 * Atomically grab references, so that those bits are not released
622 * back to the MDS mid-read.
623 *
624 * Hmm, the sync read case isn't actually async... should it be?
625 */
626static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov,
627			     unsigned long nr_segs, loff_t pos)
628{
629	struct file *filp = iocb->ki_filp;
630	struct ceph_file_info *fi = filp->private_data;
631	loff_t *ppos = &iocb->ki_pos;
632	size_t len = iov->iov_len;
633	struct inode *inode = filp->f_dentry->d_inode;
634	struct ceph_inode_info *ci = ceph_inode(inode);
635	void __user *base = iov->iov_base;
636	ssize_t ret;
637	int want, got = 0;
638	int checkeof = 0, read = 0;
639
640	dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
641	     inode, ceph_vinop(inode), pos, (unsigned)len, inode);
642again:
643	__ceph_do_pending_vmtruncate(inode);
 
 
644	if (fi->fmode & CEPH_FILE_MODE_LAZY)
645		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
646	else
647		want = CEPH_CAP_FILE_CACHE;
648	ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1);
649	if (ret < 0)
650		goto out;
651	dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
652	     inode, ceph_vinop(inode), pos, (unsigned)len,
653	     ceph_cap_string(got));
654
655	if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
656	    (iocb->ki_filp->f_flags & O_DIRECT) ||
657	    (inode->i_sb->s_flags & MS_SYNCHRONOUS) ||
658	    (fi->flags & CEPH_F_SYNC))
659		/* hmm, this isn't really async... */
660		ret = ceph_sync_read(filp, base, len, ppos, &checkeof);
661	else
662		ret = generic_file_aio_read(iocb, iov, nr_segs, pos);
663
664out:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
665	dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
666	     inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
 
 
 
 
667	ceph_put_cap_refs(ci, got);
 
 
 
 
 
 
 
 
 
668
669	if (checkeof && ret >= 0) {
670		int statret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
671
672		/* hit EOF or hole? */
673		if (statret == 0 && *ppos < inode->i_size) {
674			dout("aio_read sync_read hit hole, ppos %lld < size %lld, reading more\n", *ppos, inode->i_size);
 
 
 
675			read += ret;
676			base += ret;
677			len -= ret;
678			checkeof = 0;
679			goto again;
680		}
681	}
 
682	if (ret >= 0)
683		ret += read;
684
685	return ret;
686}
687
688/*
689 * Take cap references to avoid releasing caps to MDS mid-write.
690 *
691 * If we are synchronous, and write with an old snap context, the OSD
692 * may return EOLDSNAPC.  In that case, retry the write.. _after_
693 * dropping our cap refs and allowing the pending snap to logically
694 * complete _before_ this write occurs.
695 *
696 * If we are near ENOSPC, write synchronously.
697 */
698static ssize_t ceph_aio_write(struct kiocb *iocb, const struct iovec *iov,
699		       unsigned long nr_segs, loff_t pos)
700{
701	struct file *file = iocb->ki_filp;
702	struct ceph_file_info *fi = file->private_data;
703	struct inode *inode = file->f_dentry->d_inode;
704	struct ceph_inode_info *ci = ceph_inode(inode);
705	struct ceph_osd_client *osdc =
706		&ceph_sb_to_client(inode->i_sb)->client->osdc;
707	loff_t endoff = pos + iov->iov_len;
708	int want, got = 0;
709	int ret, err;
 
710
711	if (ceph_snap(inode) != CEPH_NOSNAP)
712		return -EROFS;
713
 
 
 
 
714retry_snap:
715	if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL))
716		return -ENOSPC;
717	__ceph_do_pending_vmtruncate(inode);
718	dout("aio_write %p %llx.%llx %llu~%u getting caps. i_size %llu\n",
719	     inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len,
720	     inode->i_size);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
721	if (fi->fmode & CEPH_FILE_MODE_LAZY)
722		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
723	else
724		want = CEPH_CAP_FILE_BUFFER;
725	ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, endoff);
726	if (ret < 0)
727		goto out_put;
 
 
728
729	dout("aio_write %p %llx.%llx %llu~%u  got cap refs on %s\n",
730	     inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len,
731	     ceph_cap_string(got));
732
733	if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
734	    (iocb->ki_filp->f_flags & O_DIRECT) ||
735	    (inode->i_sb->s_flags & MS_SYNCHRONOUS) ||
736	    (fi->flags & CEPH_F_SYNC)) {
737		ret = ceph_sync_write(file, iov->iov_base, iov->iov_len,
738			&iocb->ki_pos);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
739	} else {
740		/*
741		 * buffered write; drop Fw early to avoid slow
742		 * revocation if we get stuck on balance_dirty_pages
 
 
 
743		 */
744		int dirty;
745
746		spin_lock(&inode->i_lock);
747		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
748		spin_unlock(&inode->i_lock);
749		ceph_put_cap_refs(ci, got);
750
751		ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
752		if ((ret >= 0 || ret == -EIOCBQUEUED) &&
753		    ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host)
754		     || ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
755			err = vfs_fsync_range(file, pos, pos + ret - 1, 1);
756			if (err < 0)
757				ret = err;
758		}
759
760		if (dirty)
761			__mark_inode_dirty(inode, dirty);
762		goto out;
763	}
764
765	if (ret >= 0) {
766		int dirty;
767		spin_lock(&inode->i_lock);
768		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
769		spin_unlock(&inode->i_lock);
 
 
 
770		if (dirty)
771			__mark_inode_dirty(inode, dirty);
 
 
772	}
773
774out_put:
775	dout("aio_write %p %llx.%llx %llu~%u  dropping cap refs on %s\n",
776	     inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len,
777	     ceph_cap_string(got));
778	ceph_put_cap_refs(ci, got);
779
780out:
781	if (ret == -EOLDSNAPC) {
782		dout("aio_write %p %llx.%llx %llu~%u got EOLDSNAPC, retrying\n",
783		     inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len);
784		goto retry_snap;
785	}
786
787	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
788}
789
790/*
791 * llseek.  be sure to verify file size on SEEK_END.
792 */
793static loff_t ceph_llseek(struct file *file, loff_t offset, int origin)
794{
795	struct inode *inode = file->f_mapping->host;
796	int ret;
 
797
798	mutex_lock(&inode->i_mutex);
799	__ceph_do_pending_vmtruncate(inode);
800	if (origin != SEEK_CUR || origin != SEEK_SET) {
801		ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);
802		if (ret < 0) {
803			offset = ret;
804			goto out;
805		}
806	}
807
808	switch (origin) {
 
809	case SEEK_END:
810		offset += inode->i_size;
811		break;
812	case SEEK_CUR:
813		/*
814		 * Here we special-case the lseek(fd, 0, SEEK_CUR)
815		 * position-querying operation.  Avoid rewriting the "same"
816		 * f_pos value back to the file because a concurrent read(),
817		 * write() or lseek() might have altered it
818		 */
819		if (offset == 0) {
820			offset = file->f_pos;
821			goto out;
822		}
823		offset += file->f_pos;
824		break;
825	case SEEK_DATA:
826		if (offset >= inode->i_size) {
827			ret = -ENXIO;
828			goto out;
829		}
830		break;
831	case SEEK_HOLE:
832		if (offset >= inode->i_size) {
833			ret = -ENXIO;
834			goto out;
835		}
836		offset = inode->i_size;
837		break;
838	}
839
840	if (offset < 0 || offset > inode->i_sb->s_maxbytes) {
841		offset = -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
842		goto out;
843	}
844
845	/* Special lock needed here? */
846	if (offset != file->f_pos) {
847		file->f_pos = offset;
848		file->f_version = 0;
 
 
849	}
 
850
851out:
852	mutex_unlock(&inode->i_mutex);
853	return offset;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
854}
855
856const struct file_operations ceph_file_fops = {
857	.open = ceph_open,
858	.release = ceph_release,
859	.llseek = ceph_llseek,
860	.read = do_sync_read,
861	.write = do_sync_write,
862	.aio_read = ceph_aio_read,
863	.aio_write = ceph_aio_write,
864	.mmap = ceph_mmap,
865	.fsync = ceph_fsync,
866	.lock = ceph_lock,
867	.flock = ceph_flock,
868	.splice_read = generic_file_splice_read,
869	.splice_write = generic_file_splice_write,
870	.unlocked_ioctl = ceph_ioctl,
871	.compat_ioctl	= ceph_ioctl,
 
872};
873
v4.17
   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/ceph/ceph_debug.h>
   3
   4#include <linux/module.h>
   5#include <linux/sched.h>
   6#include <linux/slab.h>
   7#include <linux/file.h>
   8#include <linux/mount.h>
   9#include <linux/namei.h>
  10#include <linux/writeback.h>
  11#include <linux/falloc.h>
  12
  13#include "super.h"
  14#include "mds_client.h"
  15#include "cache.h"
  16
  17static __le32 ceph_flags_sys2wire(u32 flags)
  18{
  19	u32 wire_flags = 0;
  20
  21	switch (flags & O_ACCMODE) {
  22	case O_RDONLY:
  23		wire_flags |= CEPH_O_RDONLY;
  24		break;
  25	case O_WRONLY:
  26		wire_flags |= CEPH_O_WRONLY;
  27		break;
  28	case O_RDWR:
  29		wire_flags |= CEPH_O_RDWR;
  30		break;
  31	}
  32
  33	flags &= ~O_ACCMODE;
  34
  35#define ceph_sys2wire(a) if (flags & a) { wire_flags |= CEPH_##a; flags &= ~a; }
  36
  37	ceph_sys2wire(O_CREAT);
  38	ceph_sys2wire(O_EXCL);
  39	ceph_sys2wire(O_TRUNC);
  40	ceph_sys2wire(O_DIRECTORY);
  41	ceph_sys2wire(O_NOFOLLOW);
  42
  43#undef ceph_sys2wire
  44
  45	if (flags)
  46		dout("unused open flags: %x\n", flags);
  47
  48	return cpu_to_le32(wire_flags);
  49}
  50
  51/*
  52 * Ceph file operations
  53 *
  54 * Implement basic open/close functionality, and implement
  55 * read/write.
  56 *
  57 * We implement three modes of file I/O:
  58 *  - buffered uses the generic_file_aio_{read,write} helpers
  59 *
  60 *  - synchronous is used when there is multi-client read/write
  61 *    sharing, avoids the page cache, and synchronously waits for an
  62 *    ack from the OSD.
  63 *
  64 *  - direct io takes the variant of the sync path that references
  65 *    user pages directly.
  66 *
  67 * fsync() flushes and waits on dirty pages, but just queues metadata
  68 * for writeback: since the MDS can recover size and mtime there is no
  69 * need to wait for MDS acknowledgement.
  70 */
  71
  72/*
  73 * How many pages to get in one call to iov_iter_get_pages().  This
  74 * determines the size of the on-stack array used as a buffer.
  75 */
  76#define ITER_GET_BVECS_PAGES	64
  77
  78static ssize_t __iter_get_bvecs(struct iov_iter *iter, size_t maxsize,
  79				struct bio_vec *bvecs)
  80{
  81	size_t size = 0;
  82	int bvec_idx = 0;
  83
  84	if (maxsize > iov_iter_count(iter))
  85		maxsize = iov_iter_count(iter);
  86
  87	while (size < maxsize) {
  88		struct page *pages[ITER_GET_BVECS_PAGES];
  89		ssize_t bytes;
  90		size_t start;
  91		int idx = 0;
  92
  93		bytes = iov_iter_get_pages(iter, pages, maxsize - size,
  94					   ITER_GET_BVECS_PAGES, &start);
  95		if (bytes < 0)
  96			return size ?: bytes;
  97
  98		iov_iter_advance(iter, bytes);
  99		size += bytes;
 100
 101		for ( ; bytes; idx++, bvec_idx++) {
 102			struct bio_vec bv = {
 103				.bv_page = pages[idx],
 104				.bv_len = min_t(int, bytes, PAGE_SIZE - start),
 105				.bv_offset = start,
 106			};
 107
 108			bvecs[bvec_idx] = bv;
 109			bytes -= bv.bv_len;
 110			start = 0;
 111		}
 112	}
 113
 114	return size;
 115}
 116
 117/*
 118 * iov_iter_get_pages() only considers one iov_iter segment, no matter
 119 * what maxsize or maxpages are given.  For ITER_BVEC that is a single
 120 * page.
 121 *
 122 * Attempt to get up to @maxsize bytes worth of pages from @iter.
 123 * Return the number of bytes in the created bio_vec array, or an error.
 124 */
 125static ssize_t iter_get_bvecs_alloc(struct iov_iter *iter, size_t maxsize,
 126				    struct bio_vec **bvecs, int *num_bvecs)
 127{
 128	struct bio_vec *bv;
 129	size_t orig_count = iov_iter_count(iter);
 130	ssize_t bytes;
 131	int npages;
 132
 133	iov_iter_truncate(iter, maxsize);
 134	npages = iov_iter_npages(iter, INT_MAX);
 135	iov_iter_reexpand(iter, orig_count);
 136
 137	/*
 138	 * __iter_get_bvecs() may populate only part of the array -- zero it
 139	 * out.
 140	 */
 141	bv = kvmalloc_array(npages, sizeof(*bv), GFP_KERNEL | __GFP_ZERO);
 142	if (!bv)
 143		return -ENOMEM;
 144
 145	bytes = __iter_get_bvecs(iter, maxsize, bv);
 146	if (bytes < 0) {
 147		/*
 148		 * No pages were pinned -- just free the array.
 149		 */
 150		kvfree(bv);
 151		return bytes;
 152	}
 153
 154	*bvecs = bv;
 155	*num_bvecs = npages;
 156	return bytes;
 157}
 158
 159static void put_bvecs(struct bio_vec *bvecs, int num_bvecs, bool should_dirty)
 160{
 161	int i;
 162
 163	for (i = 0; i < num_bvecs; i++) {
 164		if (bvecs[i].bv_page) {
 165			if (should_dirty)
 166				set_page_dirty_lock(bvecs[i].bv_page);
 167			put_page(bvecs[i].bv_page);
 168		}
 169	}
 170	kvfree(bvecs);
 171}
 172
 173/*
 174 * Prepare an open request.  Preallocate ceph_cap to avoid an
 175 * inopportune ENOMEM later.
 176 */
 177static struct ceph_mds_request *
 178prepare_open_request(struct super_block *sb, int flags, int create_mode)
 179{
 180	struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 181	struct ceph_mds_client *mdsc = fsc->mdsc;
 182	struct ceph_mds_request *req;
 183	int want_auth = USE_ANY_MDS;
 184	int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
 185
 186	if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
 187		want_auth = USE_AUTH_MDS;
 188
 189	req = ceph_mdsc_create_request(mdsc, op, want_auth);
 190	if (IS_ERR(req))
 191		goto out;
 192	req->r_fmode = ceph_flags_to_mode(flags);
 193	req->r_args.open.flags = ceph_flags_sys2wire(flags);
 194	req->r_args.open.mode = cpu_to_le32(create_mode);
 
 195out:
 196	return req;
 197}
 198
 199static int ceph_init_file_info(struct inode *inode, struct file *file,
 200					int fmode, bool isdir)
 201{
 202	struct ceph_file_info *fi;
 203
 204	dout("%s %p %p 0%o (%s)\n", __func__, inode, file,
 205			inode->i_mode, isdir ? "dir" : "regular");
 206	BUG_ON(inode->i_fop->release != ceph_release);
 207
 208	if (isdir) {
 209		struct ceph_dir_file_info *dfi =
 210			kmem_cache_zalloc(ceph_dir_file_cachep, GFP_KERNEL);
 211		if (!dfi) {
 212			ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 213			return -ENOMEM;
 214		}
 215
 216		file->private_data = dfi;
 217		fi = &dfi->file_info;
 218		dfi->next_offset = 2;
 219		dfi->readdir_cache_idx = -1;
 220	} else {
 221		fi = kmem_cache_zalloc(ceph_file_cachep, GFP_KERNEL);
 222		if (!fi) {
 223			ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 224			return -ENOMEM;
 225		}
 226
 227		file->private_data = fi;
 228	}
 229
 230	fi->fmode = fmode;
 231	spin_lock_init(&fi->rw_contexts_lock);
 232	INIT_LIST_HEAD(&fi->rw_contexts);
 233
 234	return 0;
 235}
 236
 237/*
 238 * initialize private struct file data.
 239 * if we fail, clean up by dropping fmode reference on the ceph_inode
 240 */
 241static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
 242{
 
 243	int ret = 0;
 244
 245	switch (inode->i_mode & S_IFMT) {
 246	case S_IFREG:
 247		ceph_fscache_register_inode_cookie(inode);
 248		ceph_fscache_file_set_cookie(inode, file);
 249	case S_IFDIR:
 250		ret = ceph_init_file_info(inode, file, fmode,
 251						S_ISDIR(inode->i_mode));
 252		if (ret)
 253			return ret;
 
 
 
 
 
 
 
 254		break;
 255
 256	case S_IFLNK:
 257		dout("init_file %p %p 0%o (symlink)\n", inode, file,
 258		     inode->i_mode);
 259		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 260		break;
 261
 262	default:
 263		dout("init_file %p %p 0%o (special)\n", inode, file,
 264		     inode->i_mode);
 265		/*
 266		 * we need to drop the open ref now, since we don't
 267		 * have .release set to ceph_release.
 268		 */
 269		ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 270		BUG_ON(inode->i_fop->release == ceph_release);
 271
 272		/* call the proper open fop */
 273		ret = inode->i_fop->open(inode, file);
 274	}
 275	return ret;
 276}
 277
 278/*
 279 * try renew caps after session gets killed.
 280 */
 281int ceph_renew_caps(struct inode *inode)
 282{
 283	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
 284	struct ceph_inode_info *ci = ceph_inode(inode);
 285	struct ceph_mds_request *req;
 286	int err, flags, wanted;
 287
 288	spin_lock(&ci->i_ceph_lock);
 289	wanted = __ceph_caps_file_wanted(ci);
 290	if (__ceph_is_any_real_caps(ci) &&
 291	    (!(wanted & CEPH_CAP_ANY_WR) || ci->i_auth_cap)) {
 292		int issued = __ceph_caps_issued(ci, NULL);
 293		spin_unlock(&ci->i_ceph_lock);
 294		dout("renew caps %p want %s issued %s updating mds_wanted\n",
 295		     inode, ceph_cap_string(wanted), ceph_cap_string(issued));
 296		ceph_check_caps(ci, 0, NULL);
 297		return 0;
 298	}
 299	spin_unlock(&ci->i_ceph_lock);
 300
 301	flags = 0;
 302	if ((wanted & CEPH_CAP_FILE_RD) && (wanted & CEPH_CAP_FILE_WR))
 303		flags = O_RDWR;
 304	else if (wanted & CEPH_CAP_FILE_RD)
 305		flags = O_RDONLY;
 306	else if (wanted & CEPH_CAP_FILE_WR)
 307		flags = O_WRONLY;
 308#ifdef O_LAZY
 309	if (wanted & CEPH_CAP_FILE_LAZYIO)
 310		flags |= O_LAZY;
 311#endif
 312
 313	req = prepare_open_request(inode->i_sb, flags, 0);
 314	if (IS_ERR(req)) {
 315		err = PTR_ERR(req);
 316		goto out;
 317	}
 318
 319	req->r_inode = inode;
 320	ihold(inode);
 321	req->r_num_caps = 1;
 322	req->r_fmode = -1;
 323
 324	err = ceph_mdsc_do_request(mdsc, NULL, req);
 325	ceph_mdsc_put_request(req);
 326out:
 327	dout("renew caps %p open result=%d\n", inode, err);
 328	return err < 0 ? err : 0;
 329}
 330
 331/*
 332 * If we already have the requisite capabilities, we can satisfy
 333 * the open request locally (no need to request new caps from the
 334 * MDS).  We do, however, need to inform the MDS (asynchronously)
 335 * if our wanted caps set expands.
 336 */
 337int ceph_open(struct inode *inode, struct file *file)
 338{
 339	struct ceph_inode_info *ci = ceph_inode(inode);
 340	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
 341	struct ceph_mds_client *mdsc = fsc->mdsc;
 342	struct ceph_mds_request *req;
 343	struct ceph_file_info *fi = file->private_data;
 
 344	int err;
 345	int flags, fmode, wanted;
 346
 347	if (fi) {
 348		dout("open file %p is already opened\n", file);
 349		return 0;
 350	}
 351
 352	/* filter out O_CREAT|O_EXCL; vfs did that already.  yuck. */
 353	flags = file->f_flags & ~(O_CREAT|O_EXCL);
 354	if (S_ISDIR(inode->i_mode))
 355		flags = O_DIRECTORY;  /* mds likes to know */
 356
 357	dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
 358	     ceph_vinop(inode), file, flags, file->f_flags);
 359	fmode = ceph_flags_to_mode(flags);
 360	wanted = ceph_caps_for_mode(fmode);
 361
 362	/* snapped files are read-only */
 363	if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
 364		return -EROFS;
 365
 366	/* trivially open snapdir */
 367	if (ceph_snap(inode) == CEPH_SNAPDIR) {
 368		spin_lock(&ci->i_ceph_lock);
 369		__ceph_get_fmode(ci, fmode);
 370		spin_unlock(&ci->i_ceph_lock);
 371		return ceph_init_file(inode, file, fmode);
 372	}
 373
 374	/*
 375	 * No need to block if we have caps on the auth MDS (for
 376	 * write) or any MDS (for read).  Update wanted set
 377	 * asynchronously.
 378	 */
 379	spin_lock(&ci->i_ceph_lock);
 380	if (__ceph_is_any_real_caps(ci) &&
 381	    (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
 382		int mds_wanted = __ceph_caps_mds_wanted(ci, true);
 383		int issued = __ceph_caps_issued(ci, NULL);
 384
 385		dout("open %p fmode %d want %s issued %s using existing\n",
 386		     inode, fmode, ceph_cap_string(wanted),
 387		     ceph_cap_string(issued));
 388		__ceph_get_fmode(ci, fmode);
 389		spin_unlock(&ci->i_ceph_lock);
 390
 391		/* adjust wanted? */
 392		if ((issued & wanted) != wanted &&
 393		    (mds_wanted & wanted) != wanted &&
 394		    ceph_snap(inode) != CEPH_SNAPDIR)
 395			ceph_check_caps(ci, 0, NULL);
 396
 397		return ceph_init_file(inode, file, fmode);
 398	} else if (ceph_snap(inode) != CEPH_NOSNAP &&
 399		   (ci->i_snap_caps & wanted) == wanted) {
 400		__ceph_get_fmode(ci, fmode);
 401		spin_unlock(&ci->i_ceph_lock);
 402		return ceph_init_file(inode, file, fmode);
 403	}
 404
 405	spin_unlock(&ci->i_ceph_lock);
 406
 407	dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
 408	req = prepare_open_request(inode->i_sb, flags, 0);
 409	if (IS_ERR(req)) {
 410		err = PTR_ERR(req);
 411		goto out;
 412	}
 413	req->r_inode = inode;
 414	ihold(inode);
 415
 416	req->r_num_caps = 1;
 417	err = ceph_mdsc_do_request(mdsc, NULL, req);
 
 
 
 418	if (!err)
 419		err = ceph_init_file(inode, file, req->r_fmode);
 420	ceph_mdsc_put_request(req);
 421	dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
 422out:
 423	return err;
 424}
 425
 426
 427/*
 428 * Do a lookup + open with a single request.  If we get a non-existent
 429 * file or symlink, return 1 so the VFS can retry.
 
 
 
 
 
 
 
 
 430 */
 431int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 432		     struct file *file, unsigned flags, umode_t mode,
 433		     int *opened)
 434{
 435	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 436	struct ceph_mds_client *mdsc = fsc->mdsc;
 
 437	struct ceph_mds_request *req;
 438	struct dentry *dn;
 439	struct ceph_acls_info acls = {};
 440	int mask;
 441	int err;
 
 442
 443	dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
 444	     dir, dentry, dentry,
 445	     d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
 446
 447	if (dentry->d_name.len > NAME_MAX)
 448		return -ENAMETOOLONG;
 449
 450	if (flags & O_CREAT) {
 451		if (ceph_quota_is_max_files_exceeded(dir))
 452			return -EDQUOT;
 453		err = ceph_pre_init_acls(dir, &mode, &acls);
 454		if (err < 0)
 455			return err;
 456	}
 457
 458	/* do the open */
 459	req = prepare_open_request(dir->i_sb, flags, mode);
 460	if (IS_ERR(req)) {
 461		err = PTR_ERR(req);
 462		goto out_acl;
 463	}
 464	req->r_dentry = dget(dentry);
 465	req->r_num_caps = 2;
 466	if (flags & O_CREAT) {
 467		req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 468		req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 469		if (acls.pagelist) {
 470			req->r_pagelist = acls.pagelist;
 471			acls.pagelist = NULL;
 472		}
 473	}
 474
 475       mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
 476       if (ceph_security_xattr_wanted(dir))
 477               mask |= CEPH_CAP_XATTR_SHARED;
 478       req->r_args.open.mask = cpu_to_le32(mask);
 479
 480	req->r_parent = dir;
 481	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 482	err = ceph_mdsc_do_request(mdsc,
 483				   (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
 484				   req);
 485	err = ceph_handle_snapdir(req, dentry, err);
 486	if (err)
 487		goto out_req;
 488
 489	if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
 490		err = ceph_handle_notrace_create(dir, dentry);
 491
 492	if (d_in_lookup(dentry)) {
 493		dn = ceph_finish_lookup(req, dentry, err);
 494		if (IS_ERR(dn))
 495			err = PTR_ERR(dn);
 496	} else {
 497		/* we were given a hashed negative dentry */
 498		dn = NULL;
 499	}
 500	if (err)
 501		goto out_req;
 502	if (dn || d_really_is_negative(dentry) || d_is_symlink(dentry)) {
 503		/* make vfs retry on splice, ENOENT, or symlink */
 504		dout("atomic_open finish_no_open on dn %p\n", dn);
 505		err = finish_no_open(file, dn);
 506	} else {
 507		dout("atomic_open finish_open on dn %p\n", dn);
 508		if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
 509			ceph_init_inode_acls(d_inode(dentry), &acls);
 510			*opened |= FILE_CREATED;
 511		}
 512		err = finish_open(file, dentry, ceph_open, opened);
 513	}
 514out_req:
 515	if (!req->r_err && req->r_target_inode)
 516		ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
 517	ceph_mdsc_put_request(req);
 518out_acl:
 519	ceph_release_acls_info(&acls);
 520	dout("atomic_open result=%d\n", err);
 521	return err;
 522}
 523
 524int ceph_release(struct inode *inode, struct file *file)
 525{
 526	struct ceph_inode_info *ci = ceph_inode(inode);
 
 527
 528	if (S_ISDIR(inode->i_mode)) {
 529		struct ceph_dir_file_info *dfi = file->private_data;
 530		dout("release inode %p dir file %p\n", inode, file);
 531		WARN_ON(!list_empty(&dfi->file_info.rw_contexts));
 532
 533		ceph_put_fmode(ci, dfi->file_info.fmode);
 534
 535		if (dfi->last_readdir)
 536			ceph_mdsc_put_request(dfi->last_readdir);
 537		kfree(dfi->last_name);
 538		kfree(dfi->dir_info);
 539		kmem_cache_free(ceph_dir_file_cachep, dfi);
 540	} else {
 541		struct ceph_file_info *fi = file->private_data;
 542		dout("release inode %p regular file %p\n", inode, file);
 543		WARN_ON(!list_empty(&fi->rw_contexts));
 544
 545		ceph_put_fmode(ci, fi->fmode);
 546		kmem_cache_free(ceph_file_cachep, fi);
 547	}
 548
 549	/* wake up anyone waiting for caps on this inode */
 550	wake_up_all(&ci->i_cap_wq);
 551	return 0;
 552}
 553
 554enum {
 555	HAVE_RETRIED = 1,
 556	CHECK_EOF =    2,
 557	READ_INLINE =  3,
 558};
 559
 560/*
 561 * Read a range of bytes striped over one or more objects.  Iterate over
 562 * objects we stripe over.  (That's not atomic, but good enough for now.)
 563 *
 564 * If we get a short result from the OSD, check against i_size; we need to
 565 * only return a short read to the caller if we hit EOF.
 566 */
 567static int striped_read(struct inode *inode,
 568			u64 pos, u64 len,
 569			struct page **pages, int num_pages,
 570			int page_align, int *checkeof)
 
 571{
 572	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 573	struct ceph_inode_info *ci = ceph_inode(inode);
 574	u64 this_len;
 575	loff_t i_size;
 576	int page_idx;
 577	int ret, read = 0;
 
 
 578	bool hit_stripe, was_short;
 579
 580	/*
 581	 * we may need to do multiple reads.  not atomic, unfortunately.
 582	 */
 
 
 
 
 
 
 
 583more:
 584	this_len = len;
 585	page_idx = (page_align + read) >> PAGE_SHIFT;
 
 
 
 586	ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
 587				  &ci->i_layout, pos, &this_len,
 588				  ci->i_truncate_seq, ci->i_truncate_size,
 589				  pages + page_idx, num_pages - page_idx,
 590				  ((page_align + read) & ~PAGE_MASK));
 591	if (ret == -ENOENT)
 592		ret = 0;
 593	hit_stripe = this_len < len;
 594	was_short = ret >= 0 && ret < this_len;
 595	dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, len, read,
 596	     ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
 597
 598	i_size = i_size_read(inode);
 599	if (ret >= 0) {
 600		if (was_short && (pos + ret < i_size)) {
 601			int zlen = min(this_len - ret, i_size - pos - ret);
 602			int zoff = page_align + read + ret;
 603			dout(" zero gap %llu to %llu\n",
 604			     pos + ret, pos + ret + zlen);
 605			ceph_zero_page_vector_range(zoff, zlen, pages);
 606			ret += zlen;
 607		}
 608
 609		read += ret;
 610		pos += ret;
 611		len -= ret;
 
 
 
 612
 613		/* hit stripe and need continue*/
 614		if (len && hit_stripe && pos < i_size)
 615			goto more;
 616	}
 617
 618	if (read > 0) {
 619		ret = read;
 620		/* did we bounce off eof? */
 621		if (pos + len > i_size)
 622			*checkeof = CHECK_EOF;
 
 
 
 
 
 
 
 
 
 
 
 623	}
 624
 
 
 625	dout("striped_read returns %d\n", ret);
 626	return ret;
 627}
 628
 629/*
 630 * Completely synchronous read and write methods.  Direct from __user
 631 * buffer to osd, or directly to user pages (if O_DIRECT).
 632 *
 633 * If the read spans object boundary, just do multiple reads.
 634 */
 635static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to,
 636			      int *checkeof)
 637{
 638	struct file *file = iocb->ki_filp;
 639	struct inode *inode = file_inode(file);
 640	struct page **pages;
 641	u64 off = iocb->ki_pos;
 642	int num_pages;
 643	ssize_t ret;
 644	size_t len = iov_iter_count(to);
 645
 646	dout("sync_read on file %p %llu~%u %s\n", file, off, (unsigned)len,
 647	     (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
 648
 649	if (!len)
 650		return 0;
 
 
 
 
 
 
 
 
 651	/*
 652	 * flush any page cache pages in this range.  this
 653	 * will make concurrent normal and sync io slow,
 654	 * but it will at least behave sensibly when they are
 655	 * in sequence.
 656	 */
 657	ret = filemap_write_and_wait_range(inode->i_mapping, off,
 658						off + len);
 659	if (ret < 0)
 660		return ret;
 
 
 
 
 661
 662	if (unlikely(to->type & ITER_PIPE)) {
 663		size_t page_off;
 664		ret = iov_iter_get_pages_alloc(to, &pages, len,
 665					       &page_off);
 666		if (ret <= 0)
 667			return -ENOMEM;
 668		num_pages = DIV_ROUND_UP(ret + page_off, PAGE_SIZE);
 669
 670		ret = striped_read(inode, off, ret, pages, num_pages,
 671				   page_off, checkeof);
 672		if (ret > 0) {
 673			iov_iter_advance(to, ret);
 674			off += ret;
 675		} else {
 676			iov_iter_advance(to, 0);
 677		}
 678		ceph_put_page_vector(pages, num_pages, false);
 679	} else {
 680		num_pages = calc_pages_for(off, len);
 681		pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
 682		if (IS_ERR(pages))
 683			return PTR_ERR(pages);
 684
 685		ret = striped_read(inode, off, len, pages, num_pages,
 686				   (off & ~PAGE_MASK), checkeof);
 687		if (ret > 0) {
 688			int l, k = 0;
 689			size_t left = ret;
 690
 691			while (left) {
 692				size_t page_off = off & ~PAGE_MASK;
 693				size_t copy = min_t(size_t, left,
 694						    PAGE_SIZE - page_off);
 695				l = copy_page_to_iter(pages[k++], page_off,
 696						      copy, to);
 697				off += l;
 698				left -= l;
 699				if (l < copy)
 700					break;
 701			}
 702		}
 703		ceph_release_page_vector(pages, num_pages);
 704	}
 705
 706	if (off > iocb->ki_pos) {
 707		ret = off - iocb->ki_pos;
 708		iocb->ki_pos = off;
 709	}
 710
 711	dout("sync_read result %zd\n", ret);
 712	return ret;
 713}
 714
 715struct ceph_aio_request {
 716	struct kiocb *iocb;
 717	size_t total_len;
 718	bool write;
 719	bool should_dirty;
 720	int error;
 721	struct list_head osd_reqs;
 722	unsigned num_reqs;
 723	atomic_t pending_reqs;
 724	struct timespec mtime;
 725	struct ceph_cap_flush *prealloc_cf;
 726};
 727
 728struct ceph_aio_work {
 729	struct work_struct work;
 730	struct ceph_osd_request *req;
 731};
 732
 733static void ceph_aio_retry_work(struct work_struct *work);
 734
 735static void ceph_aio_complete(struct inode *inode,
 736			      struct ceph_aio_request *aio_req)
 737{
 738	struct ceph_inode_info *ci = ceph_inode(inode);
 739	int ret;
 740
 741	if (!atomic_dec_and_test(&aio_req->pending_reqs))
 742		return;
 743
 744	ret = aio_req->error;
 745	if (!ret)
 746		ret = aio_req->total_len;
 747
 748	dout("ceph_aio_complete %p rc %d\n", inode, ret);
 749
 750	if (ret >= 0 && aio_req->write) {
 751		int dirty;
 752
 753		loff_t endoff = aio_req->iocb->ki_pos + aio_req->total_len;
 754		if (endoff > i_size_read(inode)) {
 755			if (ceph_inode_set_size(inode, endoff))
 756				ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
 757		}
 758
 759		spin_lock(&ci->i_ceph_lock);
 760		ci->i_inline_version = CEPH_INLINE_NONE;
 761		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
 762					       &aio_req->prealloc_cf);
 763		spin_unlock(&ci->i_ceph_lock);
 764		if (dirty)
 765			__mark_inode_dirty(inode, dirty);
 766
 767	}
 768
 769	ceph_put_cap_refs(ci, (aio_req->write ? CEPH_CAP_FILE_WR :
 770						CEPH_CAP_FILE_RD));
 771
 772	aio_req->iocb->ki_complete(aio_req->iocb, ret, 0);
 773
 774	ceph_free_cap_flush(aio_req->prealloc_cf);
 775	kfree(aio_req);
 776}
 777
 778static void ceph_aio_complete_req(struct ceph_osd_request *req)
 779{
 780	int rc = req->r_result;
 781	struct inode *inode = req->r_inode;
 782	struct ceph_aio_request *aio_req = req->r_priv;
 783	struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
 784
 785	BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_BVECS);
 786	BUG_ON(!osd_data->num_bvecs);
 787
 788	dout("ceph_aio_complete_req %p rc %d bytes %u\n",
 789	     inode, rc, osd_data->bvec_pos.iter.bi_size);
 790
 791	if (rc == -EOLDSNAPC) {
 792		struct ceph_aio_work *aio_work;
 793		BUG_ON(!aio_req->write);
 794
 795		aio_work = kmalloc(sizeof(*aio_work), GFP_NOFS);
 796		if (aio_work) {
 797			INIT_WORK(&aio_work->work, ceph_aio_retry_work);
 798			aio_work->req = req;
 799			queue_work(ceph_inode_to_client(inode)->wb_wq,
 800				   &aio_work->work);
 801			return;
 802		}
 803		rc = -ENOMEM;
 804	} else if (!aio_req->write) {
 805		if (rc == -ENOENT)
 806			rc = 0;
 807		if (rc >= 0 && osd_data->bvec_pos.iter.bi_size > rc) {
 808			struct iov_iter i;
 809			int zlen = osd_data->bvec_pos.iter.bi_size - rc;
 810
 811			/*
 812			 * If read is satisfied by single OSD request,
 813			 * it can pass EOF. Otherwise read is within
 814			 * i_size.
 815			 */
 816			if (aio_req->num_reqs == 1) {
 817				loff_t i_size = i_size_read(inode);
 818				loff_t endoff = aio_req->iocb->ki_pos + rc;
 819				if (endoff < i_size)
 820					zlen = min_t(size_t, zlen,
 821						     i_size - endoff);
 822				aio_req->total_len = rc + zlen;
 823			}
 824
 825			iov_iter_bvec(&i, ITER_BVEC, osd_data->bvec_pos.bvecs,
 826				      osd_data->num_bvecs,
 827				      osd_data->bvec_pos.iter.bi_size);
 828			iov_iter_advance(&i, rc);
 829			iov_iter_zero(zlen, &i);
 830		}
 831	}
 832
 833	put_bvecs(osd_data->bvec_pos.bvecs, osd_data->num_bvecs,
 834		  aio_req->should_dirty);
 835	ceph_osdc_put_request(req);
 836
 837	if (rc < 0)
 838		cmpxchg(&aio_req->error, 0, rc);
 839
 840	ceph_aio_complete(inode, aio_req);
 841	return;
 842}
 843
 844static void ceph_aio_retry_work(struct work_struct *work)
 845{
 846	struct ceph_aio_work *aio_work =
 847		container_of(work, struct ceph_aio_work, work);
 848	struct ceph_osd_request *orig_req = aio_work->req;
 849	struct ceph_aio_request *aio_req = orig_req->r_priv;
 850	struct inode *inode = orig_req->r_inode;
 851	struct ceph_inode_info *ci = ceph_inode(inode);
 852	struct ceph_snap_context *snapc;
 853	struct ceph_osd_request *req;
 854	int ret;
 855
 856	spin_lock(&ci->i_ceph_lock);
 857	if (__ceph_have_pending_cap_snap(ci)) {
 858		struct ceph_cap_snap *capsnap =
 859			list_last_entry(&ci->i_cap_snaps,
 860					struct ceph_cap_snap,
 861					ci_item);
 862		snapc = ceph_get_snap_context(capsnap->context);
 863	} else {
 864		BUG_ON(!ci->i_head_snapc);
 865		snapc = ceph_get_snap_context(ci->i_head_snapc);
 866	}
 867	spin_unlock(&ci->i_ceph_lock);
 868
 869	req = ceph_osdc_alloc_request(orig_req->r_osdc, snapc, 2,
 870			false, GFP_NOFS);
 871	if (!req) {
 872		ret = -ENOMEM;
 873		req = orig_req;
 874		goto out;
 875	}
 876
 877	req->r_flags = /* CEPH_OSD_FLAG_ORDERSNAP | */ CEPH_OSD_FLAG_WRITE;
 878	ceph_oloc_copy(&req->r_base_oloc, &orig_req->r_base_oloc);
 879	ceph_oid_copy(&req->r_base_oid, &orig_req->r_base_oid);
 880
 881	ret = ceph_osdc_alloc_messages(req, GFP_NOFS);
 882	if (ret) {
 883		ceph_osdc_put_request(req);
 884		req = orig_req;
 885		goto out;
 886	}
 887
 888	req->r_ops[0] = orig_req->r_ops[0];
 889
 890	req->r_mtime = aio_req->mtime;
 891	req->r_data_offset = req->r_ops[0].extent.offset;
 892
 893	ceph_osdc_put_request(orig_req);
 894
 895	req->r_callback = ceph_aio_complete_req;
 896	req->r_inode = inode;
 897	req->r_priv = aio_req;
 898	req->r_abort_on_full = true;
 899
 900	ret = ceph_osdc_start_request(req->r_osdc, req, false);
 901out:
 902	if (ret < 0) {
 903		req->r_result = ret;
 904		ceph_aio_complete_req(req);
 905	}
 906
 907	ceph_put_snap_context(snapc);
 908	kfree(aio_work);
 909}
 910
 911static ssize_t
 912ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
 913		       struct ceph_snap_context *snapc,
 914		       struct ceph_cap_flush **pcf)
 915{
 916	struct file *file = iocb->ki_filp;
 917	struct inode *inode = file_inode(file);
 918	struct ceph_inode_info *ci = ceph_inode(inode);
 919	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 920	struct ceph_vino vino;
 921	struct ceph_osd_request *req;
 922	struct bio_vec *bvecs;
 923	struct ceph_aio_request *aio_req = NULL;
 924	int num_pages = 0;
 925	int flags;
 926	int ret;
 927	struct timespec mtime = current_time(inode);
 928	size_t count = iov_iter_count(iter);
 929	loff_t pos = iocb->ki_pos;
 930	bool write = iov_iter_rw(iter) == WRITE;
 931	bool should_dirty = !write && iter_is_iovec(iter);
 932
 933	if (write && ceph_snap(file_inode(file)) != CEPH_NOSNAP)
 934		return -EROFS;
 935
 936	dout("sync_direct_%s on file %p %lld~%u snapc %p seq %lld\n",
 937	     (write ? "write" : "read"), file, pos, (unsigned)count,
 938	     snapc, snapc->seq);
 939
 940	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
 941	if (ret < 0)
 942		return ret;
 943
 944	if (write) {
 945		int ret2 = invalidate_inode_pages2_range(inode->i_mapping,
 946					pos >> PAGE_SHIFT,
 947					(pos + count) >> PAGE_SHIFT);
 948		if (ret2 < 0)
 949			dout("invalidate_inode_pages2_range returned %d\n", ret2);
 950
 951		flags = /* CEPH_OSD_FLAG_ORDERSNAP | */ CEPH_OSD_FLAG_WRITE;
 952	} else {
 953		flags = CEPH_OSD_FLAG_READ;
 954	}
 955
 956	while (iov_iter_count(iter) > 0) {
 957		u64 size = iov_iter_count(iter);
 958		ssize_t len;
 959
 960		if (write)
 961			size = min_t(u64, size, fsc->mount_options->wsize);
 962		else
 963			size = min_t(u64, size, fsc->mount_options->rsize);
 964
 965		vino = ceph_vino(inode);
 966		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
 967					    vino, pos, &size, 0,
 968					    1,
 969					    write ? CEPH_OSD_OP_WRITE :
 970						    CEPH_OSD_OP_READ,
 971					    flags, snapc,
 972					    ci->i_truncate_seq,
 973					    ci->i_truncate_size,
 974					    false);
 975		if (IS_ERR(req)) {
 976			ret = PTR_ERR(req);
 977			break;
 978		}
 979
 980		len = iter_get_bvecs_alloc(iter, size, &bvecs, &num_pages);
 981		if (len < 0) {
 982			ceph_osdc_put_request(req);
 983			ret = len;
 984			break;
 985		}
 986		if (len != size)
 987			osd_req_op_extent_update(req, 0, len);
 988
 989		/*
 990		 * To simplify error handling, allow AIO when IO within i_size
 991		 * or IO can be satisfied by single OSD request.
 992		 */
 993		if (pos == iocb->ki_pos && !is_sync_kiocb(iocb) &&
 994		    (len == count || pos + count <= i_size_read(inode))) {
 995			aio_req = kzalloc(sizeof(*aio_req), GFP_KERNEL);
 996			if (aio_req) {
 997				aio_req->iocb = iocb;
 998				aio_req->write = write;
 999				aio_req->should_dirty = should_dirty;
1000				INIT_LIST_HEAD(&aio_req->osd_reqs);
1001				if (write) {
1002					aio_req->mtime = mtime;
1003					swap(aio_req->prealloc_cf, *pcf);
1004				}
1005			}
1006			/* ignore error */
1007		}
1008
1009		if (write) {
1010			/*
1011			 * throw out any page cache pages in this range. this
1012			 * may block.
1013			 */
1014			truncate_inode_pages_range(inode->i_mapping, pos,
1015					(pos+len) | (PAGE_SIZE - 1));
1016
1017			req->r_mtime = mtime;
1018		}
1019
1020		osd_req_op_extent_osd_data_bvecs(req, 0, bvecs, num_pages, len);
1021
1022		if (aio_req) {
1023			aio_req->total_len += len;
1024			aio_req->num_reqs++;
1025			atomic_inc(&aio_req->pending_reqs);
1026
1027			req->r_callback = ceph_aio_complete_req;
1028			req->r_inode = inode;
1029			req->r_priv = aio_req;
1030			list_add_tail(&req->r_unsafe_item, &aio_req->osd_reqs);
1031
1032			pos += len;
1033			continue;
1034		}
1035
1036		ret = ceph_osdc_start_request(req->r_osdc, req, false);
1037		if (!ret)
1038			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1039
1040		size = i_size_read(inode);
1041		if (!write) {
1042			if (ret == -ENOENT)
1043				ret = 0;
1044			if (ret >= 0 && ret < len && pos + ret < size) {
1045				struct iov_iter i;
1046				int zlen = min_t(size_t, len - ret,
1047						 size - pos - ret);
1048
1049				iov_iter_bvec(&i, ITER_BVEC, bvecs, num_pages,
1050					      len);
1051				iov_iter_advance(&i, ret);
1052				iov_iter_zero(zlen, &i);
1053				ret += zlen;
1054			}
1055			if (ret >= 0)
1056				len = ret;
1057		}
1058
1059		put_bvecs(bvecs, num_pages, should_dirty);
1060		ceph_osdc_put_request(req);
1061		if (ret < 0)
1062			break;
1063
1064		pos += len;
1065		if (!write && pos >= size)
1066			break;
1067
1068		if (write && pos > size) {
1069			if (ceph_inode_set_size(inode, pos))
1070				ceph_check_caps(ceph_inode(inode),
1071						CHECK_CAPS_AUTHONLY,
1072						NULL);
1073		}
1074	}
1075
1076	if (aio_req) {
1077		LIST_HEAD(osd_reqs);
1078
1079		if (aio_req->num_reqs == 0) {
1080			kfree(aio_req);
1081			return ret;
1082		}
1083
1084		ceph_get_cap_refs(ci, write ? CEPH_CAP_FILE_WR :
1085					      CEPH_CAP_FILE_RD);
1086
1087		list_splice(&aio_req->osd_reqs, &osd_reqs);
1088		while (!list_empty(&osd_reqs)) {
1089			req = list_first_entry(&osd_reqs,
1090					       struct ceph_osd_request,
1091					       r_unsafe_item);
1092			list_del_init(&req->r_unsafe_item);
1093			if (ret >= 0)
1094				ret = ceph_osdc_start_request(req->r_osdc,
1095							      req, false);
1096			if (ret < 0) {
1097				req->r_result = ret;
1098				ceph_aio_complete_req(req);
1099			}
1100		}
1101		return -EIOCBQUEUED;
1102	}
1103
1104	if (ret != -EOLDSNAPC && pos > iocb->ki_pos) {
1105		ret = pos - iocb->ki_pos;
1106		iocb->ki_pos = pos;
1107	}
1108	return ret;
1109}
1110
1111/*
1112 * Synchronous write, straight from __user pointer or user pages.
 
1113 *
1114 * If write spans object boundary, just do multiple writes.  (For a
1115 * correct atomic write, we should e.g. take write locks on all
1116 * objects, rollback on failure, etc.)
1117 */
1118static ssize_t
1119ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos,
1120		struct ceph_snap_context *snapc)
1121{
1122	struct file *file = iocb->ki_filp;
1123	struct inode *inode = file_inode(file);
1124	struct ceph_inode_info *ci = ceph_inode(inode);
1125	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1126	struct ceph_vino vino;
1127	struct ceph_osd_request *req;
1128	struct page **pages;
 
 
1129	u64 len;
1130	int num_pages;
1131	int written = 0;
1132	int flags;
 
 
 
 
1133	int ret;
1134	bool check_caps = false;
1135	struct timespec mtime = current_time(inode);
1136	size_t count = iov_iter_count(from);
1137
1138	if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
1139		return -EROFS;
1140
1141	dout("sync_write on file %p %lld~%u snapc %p seq %lld\n",
1142	     file, pos, (unsigned)count, snapc, snapc->seq);
 
 
 
 
 
1143
1144	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
1145	if (ret < 0)
1146		return ret;
1147
1148	ret = invalidate_inode_pages2_range(inode->i_mapping,
1149					    pos >> PAGE_SHIFT,
1150					    (pos + count) >> PAGE_SHIFT);
1151	if (ret < 0)
1152		dout("invalidate_inode_pages2_range returned %d\n", ret);
1153
1154	flags = /* CEPH_OSD_FLAG_ORDERSNAP | */ CEPH_OSD_FLAG_WRITE;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1155
1156	while ((len = iov_iter_count(from)) > 0) {
1157		size_t left;
1158		int n;
1159
1160		vino = ceph_vino(inode);
1161		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1162					    vino, pos, &len, 0, 1,
1163					    CEPH_OSD_OP_WRITE, flags, snapc,
1164					    ci->i_truncate_seq,
1165					    ci->i_truncate_size,
1166					    false);
1167		if (IS_ERR(req)) {
1168			ret = PTR_ERR(req);
1169			break;
1170		}
1171
1172		/*
1173		 * write from beginning of first page,
1174		 * regardless of io alignment
1175		 */
1176		num_pages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
1177
1178		pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
 
1179		if (IS_ERR(pages)) {
1180			ret = PTR_ERR(pages);
1181			goto out;
1182		}
1183
1184		left = len;
1185		for (n = 0; n < num_pages; n++) {
1186			size_t plen = min_t(size_t, left, PAGE_SIZE);
1187			ret = copy_page_from_iter(pages[n], 0, plen, from);
1188			if (ret != plen) {
1189				ret = -EFAULT;
1190				break;
1191			}
1192			left -= ret;
1193		}
1194
1195		if (ret < 0) {
1196			ceph_release_page_vector(pages, num_pages);
1197			goto out;
1198		}
1199
1200		req->r_inode = inode;
 
 
 
 
 
 
 
 
1201
1202		osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
1203						false, true);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1204
1205		req->r_mtime = mtime;
1206		ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1207		if (!ret)
1208			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1209
1210out:
1211		ceph_osdc_put_request(req);
1212		if (ret != 0) {
1213			ceph_set_error_write(ci);
1214			break;
1215		}
1216
1217		ceph_clear_error_write(ci);
1218		pos += len;
1219		written += len;
1220		if (pos > i_size_read(inode)) {
1221			check_caps = ceph_inode_set_size(inode, pos);
1222			if (check_caps)
1223				ceph_check_caps(ceph_inode(inode),
1224						CHECK_CAPS_AUTHONLY,
1225						NULL);
1226		}
1227
1228	}
1229
1230	if (ret != -EOLDSNAPC && written > 0) {
1231		ret = written;
1232		iocb->ki_pos = pos;
 
 
 
 
 
1233	}
1234	return ret;
1235}
1236
1237/*
1238 * Wrap generic_file_aio_read with checks for cap bits on the inode.
1239 * Atomically grab references, so that those bits are not released
1240 * back to the MDS mid-read.
1241 *
1242 * Hmm, the sync read case isn't actually async... should it be?
1243 */
1244static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
 
1245{
1246	struct file *filp = iocb->ki_filp;
1247	struct ceph_file_info *fi = filp->private_data;
1248	size_t len = iov_iter_count(to);
1249	struct inode *inode = file_inode(filp);
 
1250	struct ceph_inode_info *ci = ceph_inode(inode);
1251	struct page *pinned_page = NULL;
1252	ssize_t ret;
1253	int want, got = 0;
1254	int retry_op = 0, read = 0;
1255
 
 
1256again:
1257	dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
1258	     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
1259
1260	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1261		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
1262	else
1263		want = CEPH_CAP_FILE_CACHE;
1264	ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page);
1265	if (ret < 0)
1266		return ret;
 
 
 
1267
1268	if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
1269	    (iocb->ki_flags & IOCB_DIRECT) ||
1270	    (fi->flags & CEPH_F_SYNC)) {
 
 
 
 
 
1271
1272		dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
1273		     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
1274		     ceph_cap_string(got));
1275
1276		if (ci->i_inline_version == CEPH_INLINE_NONE) {
1277			if (!retry_op && (iocb->ki_flags & IOCB_DIRECT)) {
1278				ret = ceph_direct_read_write(iocb, to,
1279							     NULL, NULL);
1280				if (ret >= 0 && ret < len)
1281					retry_op = CHECK_EOF;
1282			} else {
1283				ret = ceph_sync_read(iocb, to, &retry_op);
1284			}
1285		} else {
1286			retry_op = READ_INLINE;
1287		}
1288	} else {
1289		CEPH_DEFINE_RW_CONTEXT(rw_ctx, got);
1290		dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
1291		     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
1292		     ceph_cap_string(got));
1293		ceph_add_rw_context(fi, &rw_ctx);
1294		ret = generic_file_read_iter(iocb, to);
1295		ceph_del_rw_context(fi, &rw_ctx);
1296	}
1297	dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
1298	     inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
1299	if (pinned_page) {
1300		put_page(pinned_page);
1301		pinned_page = NULL;
1302	}
1303	ceph_put_cap_refs(ci, got);
1304	if (retry_op > HAVE_RETRIED && ret >= 0) {
1305		int statret;
1306		struct page *page = NULL;
1307		loff_t i_size;
1308		if (retry_op == READ_INLINE) {
1309			page = __page_cache_alloc(GFP_KERNEL);
1310			if (!page)
1311				return -ENOMEM;
1312		}
1313
1314		statret = __ceph_do_getattr(inode, page,
1315					    CEPH_STAT_CAP_INLINE_DATA, !!page);
1316		if (statret < 0) {
1317			if (page)
1318				__free_page(page);
1319			if (statret == -ENODATA) {
1320				BUG_ON(retry_op != READ_INLINE);
1321				goto again;
1322			}
1323			return statret;
1324		}
1325
1326		i_size = i_size_read(inode);
1327		if (retry_op == READ_INLINE) {
1328			BUG_ON(ret > 0 || read > 0);
1329			if (iocb->ki_pos < i_size &&
1330			    iocb->ki_pos < PAGE_SIZE) {
1331				loff_t end = min_t(loff_t, i_size,
1332						   iocb->ki_pos + len);
1333				end = min_t(loff_t, end, PAGE_SIZE);
1334				if (statret < end)
1335					zero_user_segment(page, statret, end);
1336				ret = copy_page_to_iter(page,
1337						iocb->ki_pos & ~PAGE_MASK,
1338						end - iocb->ki_pos, to);
1339				iocb->ki_pos += ret;
1340				read += ret;
1341			}
1342			if (iocb->ki_pos < i_size && read < len) {
1343				size_t zlen = min_t(size_t, len - read,
1344						    i_size - iocb->ki_pos);
1345				ret = iov_iter_zero(zlen, to);
1346				iocb->ki_pos += ret;
1347				read += ret;
1348			}
1349			__free_pages(page, 0);
1350			return read;
1351		}
1352
1353		/* hit EOF or hole? */
1354		if (retry_op == CHECK_EOF && iocb->ki_pos < i_size &&
1355		    ret < len) {
1356			dout("sync_read hit hole, ppos %lld < size %lld"
1357			     ", reading more\n", iocb->ki_pos, i_size);
1358
1359			read += ret;
 
1360			len -= ret;
1361			retry_op = HAVE_RETRIED;
1362			goto again;
1363		}
1364	}
1365
1366	if (ret >= 0)
1367		ret += read;
1368
1369	return ret;
1370}
1371
1372/*
1373 * Take cap references to avoid releasing caps to MDS mid-write.
1374 *
1375 * If we are synchronous, and write with an old snap context, the OSD
1376 * may return EOLDSNAPC.  In that case, retry the write.. _after_
1377 * dropping our cap refs and allowing the pending snap to logically
1378 * complete _before_ this write occurs.
1379 *
1380 * If we are near ENOSPC, write synchronously.
1381 */
1382static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
 
1383{
1384	struct file *file = iocb->ki_filp;
1385	struct ceph_file_info *fi = file->private_data;
1386	struct inode *inode = file_inode(file);
1387	struct ceph_inode_info *ci = ceph_inode(inode);
1388	struct ceph_osd_client *osdc =
1389		&ceph_sb_to_client(inode->i_sb)->client->osdc;
1390	struct ceph_cap_flush *prealloc_cf;
1391	ssize_t count, written = 0;
1392	int err, want, got;
1393	loff_t pos;
1394
1395	if (ceph_snap(inode) != CEPH_NOSNAP)
1396		return -EROFS;
1397
1398	prealloc_cf = ceph_alloc_cap_flush();
1399	if (!prealloc_cf)
1400		return -ENOMEM;
1401
1402retry_snap:
1403	inode_lock(inode);
1404
1405	/* We can write back this queue in page reclaim */
1406	current->backing_dev_info = inode_to_bdi(inode);
1407
1408	if (iocb->ki_flags & IOCB_APPEND) {
1409		err = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1410		if (err < 0)
1411			goto out;
1412	}
1413
1414	err = generic_write_checks(iocb, from);
1415	if (err <= 0)
1416		goto out;
1417
1418	pos = iocb->ki_pos;
1419	count = iov_iter_count(from);
1420	if (ceph_quota_is_max_bytes_exceeded(inode, pos + count)) {
1421		err = -EDQUOT;
1422		goto out;
1423	}
1424
1425	err = file_remove_privs(file);
1426	if (err)
1427		goto out;
1428
1429	err = file_update_time(file);
1430	if (err)
1431		goto out;
1432
1433	if (ci->i_inline_version != CEPH_INLINE_NONE) {
1434		err = ceph_uninline_data(file, NULL);
1435		if (err < 0)
1436			goto out;
1437	}
1438
1439	/* FIXME: not complete since it doesn't account for being at quota */
1440	if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL)) {
1441		err = -ENOSPC;
1442		goto out;
1443	}
1444
1445	dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
1446	     inode, ceph_vinop(inode), pos, count, i_size_read(inode));
1447	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1448		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1449	else
1450		want = CEPH_CAP_FILE_BUFFER;
1451	got = 0;
1452	err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, pos + count,
1453			    &got, NULL);
1454	if (err < 0)
1455		goto out;
1456
1457	dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
1458	     inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
 
1459
1460	if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
1461	    (iocb->ki_flags & IOCB_DIRECT) || (fi->flags & CEPH_F_SYNC) ||
1462	    (ci->i_ceph_flags & CEPH_I_ERROR_WRITE)) {
1463		struct ceph_snap_context *snapc;
1464		struct iov_iter data;
1465		inode_unlock(inode);
1466
1467		spin_lock(&ci->i_ceph_lock);
1468		if (__ceph_have_pending_cap_snap(ci)) {
1469			struct ceph_cap_snap *capsnap =
1470					list_last_entry(&ci->i_cap_snaps,
1471							struct ceph_cap_snap,
1472							ci_item);
1473			snapc = ceph_get_snap_context(capsnap->context);
1474		} else {
1475			BUG_ON(!ci->i_head_snapc);
1476			snapc = ceph_get_snap_context(ci->i_head_snapc);
1477		}
1478		spin_unlock(&ci->i_ceph_lock);
1479
1480		/* we might need to revert back to that point */
1481		data = *from;
1482		if (iocb->ki_flags & IOCB_DIRECT)
1483			written = ceph_direct_read_write(iocb, &data, snapc,
1484							 &prealloc_cf);
1485		else
1486			written = ceph_sync_write(iocb, &data, pos, snapc);
1487		if (written > 0)
1488			iov_iter_advance(from, written);
1489		ceph_put_snap_context(snapc);
1490	} else {
1491		/*
1492		 * No need to acquire the i_truncate_mutex. Because
1493		 * the MDS revokes Fwb caps before sending truncate
1494		 * message to us. We can't get Fwb cap while there
1495		 * are pending vmtruncate. So write and vmtruncate
1496		 * can not run at the same time
1497		 */
1498		written = generic_perform_write(file, from, pos);
1499		if (likely(written >= 0))
1500			iocb->ki_pos = pos + written;
1501		inode_unlock(inode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1502	}
1503
1504	if (written >= 0) {
1505		int dirty;
1506
1507		spin_lock(&ci->i_ceph_lock);
1508		ci->i_inline_version = CEPH_INLINE_NONE;
1509		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1510					       &prealloc_cf);
1511		spin_unlock(&ci->i_ceph_lock);
1512		if (dirty)
1513			__mark_inode_dirty(inode, dirty);
1514		if (ceph_quota_is_max_bytes_approaching(inode, iocb->ki_pos))
1515			ceph_check_caps(ci, CHECK_CAPS_NODELAY, NULL);
1516	}
1517
 
1518	dout("aio_write %p %llx.%llx %llu~%u  dropping cap refs on %s\n",
1519	     inode, ceph_vinop(inode), pos, (unsigned)count,
1520	     ceph_cap_string(got));
1521	ceph_put_cap_refs(ci, got);
1522
1523	if (written == -EOLDSNAPC) {
1524		dout("aio_write %p %llx.%llx %llu~%u" "got EOLDSNAPC, retrying\n",
1525		     inode, ceph_vinop(inode), pos, (unsigned)count);
 
1526		goto retry_snap;
1527	}
1528
1529	if (written >= 0) {
1530		if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_NEARFULL))
1531			iocb->ki_flags |= IOCB_DSYNC;
1532		written = generic_write_sync(iocb, written);
1533	}
1534
1535	goto out_unlocked;
1536
1537out:
1538	inode_unlock(inode);
1539out_unlocked:
1540	ceph_free_cap_flush(prealloc_cf);
1541	current->backing_dev_info = NULL;
1542	return written ? written : err;
1543}
1544
1545/*
1546 * llseek.  be sure to verify file size on SEEK_END.
1547 */
1548static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
1549{
1550	struct inode *inode = file->f_mapping->host;
1551	loff_t i_size;
1552	loff_t ret;
1553
1554	inode_lock(inode);
1555
1556	if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
1557		ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1558		if (ret < 0)
 
1559			goto out;
 
1560	}
1561
1562	i_size = i_size_read(inode);
1563	switch (whence) {
1564	case SEEK_END:
1565		offset += i_size;
1566		break;
1567	case SEEK_CUR:
1568		/*
1569		 * Here we special-case the lseek(fd, 0, SEEK_CUR)
1570		 * position-querying operation.  Avoid rewriting the "same"
1571		 * f_pos value back to the file because a concurrent read(),
1572		 * write() or lseek() might have altered it
1573		 */
1574		if (offset == 0) {
1575			ret = file->f_pos;
1576			goto out;
1577		}
1578		offset += file->f_pos;
1579		break;
1580	case SEEK_DATA:
1581		if (offset < 0 || offset >= i_size) {
1582			ret = -ENXIO;
1583			goto out;
1584		}
1585		break;
1586	case SEEK_HOLE:
1587		if (offset < 0 || offset >= i_size) {
1588			ret = -ENXIO;
1589			goto out;
1590		}
1591		offset = i_size;
1592		break;
1593	}
1594
1595	ret = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1596
1597out:
1598	inode_unlock(inode);
1599	return ret;
1600}
1601
1602static inline void ceph_zero_partial_page(
1603	struct inode *inode, loff_t offset, unsigned size)
1604{
1605	struct page *page;
1606	pgoff_t index = offset >> PAGE_SHIFT;
1607
1608	page = find_lock_page(inode->i_mapping, index);
1609	if (page) {
1610		wait_on_page_writeback(page);
1611		zero_user(page, offset & (PAGE_SIZE - 1), size);
1612		unlock_page(page);
1613		put_page(page);
1614	}
1615}
1616
1617static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1618				      loff_t length)
1619{
1620	loff_t nearly = round_up(offset, PAGE_SIZE);
1621	if (offset < nearly) {
1622		loff_t size = nearly - offset;
1623		if (length < size)
1624			size = length;
1625		ceph_zero_partial_page(inode, offset, size);
1626		offset += size;
1627		length -= size;
1628	}
1629	if (length >= PAGE_SIZE) {
1630		loff_t size = round_down(length, PAGE_SIZE);
1631		truncate_pagecache_range(inode, offset, offset + size - 1);
1632		offset += size;
1633		length -= size;
1634	}
1635	if (length)
1636		ceph_zero_partial_page(inode, offset, length);
1637}
1638
1639static int ceph_zero_partial_object(struct inode *inode,
1640				    loff_t offset, loff_t *length)
1641{
1642	struct ceph_inode_info *ci = ceph_inode(inode);
1643	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1644	struct ceph_osd_request *req;
1645	int ret = 0;
1646	loff_t zero = 0;
1647	int op;
1648
1649	if (!length) {
1650		op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1651		length = &zero;
1652	} else {
1653		op = CEPH_OSD_OP_ZERO;
1654	}
1655
1656	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1657					ceph_vino(inode),
1658					offset, length,
1659					0, 1, op,
1660					CEPH_OSD_FLAG_WRITE,
1661					NULL, 0, 0, false);
1662	if (IS_ERR(req)) {
1663		ret = PTR_ERR(req);
1664		goto out;
1665	}
1666
1667	req->r_mtime = inode->i_mtime;
1668	ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1669	if (!ret) {
1670		ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1671		if (ret == -ENOENT)
1672			ret = 0;
1673	}
1674	ceph_osdc_put_request(req);
1675
1676out:
1677	return ret;
1678}
1679
1680static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1681{
1682	int ret = 0;
1683	struct ceph_inode_info *ci = ceph_inode(inode);
1684	s32 stripe_unit = ci->i_layout.stripe_unit;
1685	s32 stripe_count = ci->i_layout.stripe_count;
1686	s32 object_size = ci->i_layout.object_size;
1687	u64 object_set_size = object_size * stripe_count;
1688	u64 nearly, t;
1689
1690	/* round offset up to next period boundary */
1691	nearly = offset + object_set_size - 1;
1692	t = nearly;
1693	nearly -= do_div(t, object_set_size);
1694
1695	while (length && offset < nearly) {
1696		loff_t size = length;
1697		ret = ceph_zero_partial_object(inode, offset, &size);
1698		if (ret < 0)
1699			return ret;
1700		offset += size;
1701		length -= size;
1702	}
1703	while (length >= object_set_size) {
1704		int i;
1705		loff_t pos = offset;
1706		for (i = 0; i < stripe_count; ++i) {
1707			ret = ceph_zero_partial_object(inode, pos, NULL);
1708			if (ret < 0)
1709				return ret;
1710			pos += stripe_unit;
1711		}
1712		offset += object_set_size;
1713		length -= object_set_size;
1714	}
1715	while (length) {
1716		loff_t size = length;
1717		ret = ceph_zero_partial_object(inode, offset, &size);
1718		if (ret < 0)
1719			return ret;
1720		offset += size;
1721		length -= size;
1722	}
1723	return ret;
1724}
1725
1726static long ceph_fallocate(struct file *file, int mode,
1727				loff_t offset, loff_t length)
1728{
1729	struct ceph_file_info *fi = file->private_data;
1730	struct inode *inode = file_inode(file);
1731	struct ceph_inode_info *ci = ceph_inode(inode);
1732	struct ceph_osd_client *osdc =
1733		&ceph_inode_to_client(inode)->client->osdc;
1734	struct ceph_cap_flush *prealloc_cf;
1735	int want, got = 0;
1736	int dirty;
1737	int ret = 0;
1738	loff_t endoff = 0;
1739	loff_t size;
1740
1741	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
1742		return -EOPNOTSUPP;
1743
1744	if (!S_ISREG(inode->i_mode))
1745		return -EOPNOTSUPP;
1746
1747	prealloc_cf = ceph_alloc_cap_flush();
1748	if (!prealloc_cf)
1749		return -ENOMEM;
1750
1751	inode_lock(inode);
1752
1753	if (ceph_snap(inode) != CEPH_NOSNAP) {
1754		ret = -EROFS;
1755		goto unlock;
1756	}
1757
1758	if (!(mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE)) &&
1759	    ceph_quota_is_max_bytes_exceeded(inode, offset + length)) {
1760		ret = -EDQUOT;
1761		goto unlock;
1762	}
1763
1764	if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) &&
1765	    !(mode & FALLOC_FL_PUNCH_HOLE)) {
1766		ret = -ENOSPC;
1767		goto unlock;
1768	}
1769
1770	if (ci->i_inline_version != CEPH_INLINE_NONE) {
1771		ret = ceph_uninline_data(file, NULL);
1772		if (ret < 0)
1773			goto unlock;
1774	}
1775
1776	size = i_size_read(inode);
1777	if (!(mode & FALLOC_FL_KEEP_SIZE)) {
1778		endoff = offset + length;
1779		ret = inode_newsize_ok(inode, endoff);
1780		if (ret)
1781			goto unlock;
1782	}
1783
1784	if (fi->fmode & CEPH_FILE_MODE_LAZY)
1785		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1786	else
1787		want = CEPH_CAP_FILE_BUFFER;
1788
1789	ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, endoff, &got, NULL);
1790	if (ret < 0)
1791		goto unlock;
1792
1793	if (mode & FALLOC_FL_PUNCH_HOLE) {
1794		if (offset < size)
1795			ceph_zero_pagecache_range(inode, offset, length);
1796		ret = ceph_zero_objects(inode, offset, length);
1797	} else if (endoff > size) {
1798		truncate_pagecache_range(inode, size, -1);
1799		if (ceph_inode_set_size(inode, endoff))
1800			ceph_check_caps(ceph_inode(inode),
1801				CHECK_CAPS_AUTHONLY, NULL);
1802	}
1803
1804	if (!ret) {
1805		spin_lock(&ci->i_ceph_lock);
1806		ci->i_inline_version = CEPH_INLINE_NONE;
1807		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1808					       &prealloc_cf);
1809		spin_unlock(&ci->i_ceph_lock);
1810		if (dirty)
1811			__mark_inode_dirty(inode, dirty);
1812		if ((endoff > size) &&
1813		    ceph_quota_is_max_bytes_approaching(inode, endoff))
1814			ceph_check_caps(ci, CHECK_CAPS_NODELAY, NULL);
1815	}
1816
1817	ceph_put_cap_refs(ci, got);
1818unlock:
1819	inode_unlock(inode);
1820	ceph_free_cap_flush(prealloc_cf);
1821	return ret;
1822}
1823
1824const struct file_operations ceph_file_fops = {
1825	.open = ceph_open,
1826	.release = ceph_release,
1827	.llseek = ceph_llseek,
1828	.read_iter = ceph_read_iter,
1829	.write_iter = ceph_write_iter,
 
 
1830	.mmap = ceph_mmap,
1831	.fsync = ceph_fsync,
1832	.lock = ceph_lock,
1833	.flock = ceph_flock,
1834	.splice_read = generic_file_splice_read,
1835	.splice_write = iter_file_splice_write,
1836	.unlocked_ioctl = ceph_ioctl,
1837	.compat_ioctl	= ceph_ioctl,
1838	.fallocate	= ceph_fallocate,
1839};
1840