Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2530 insertions, 0 deletions

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
new file mode 100644
index 000000000..d4974c652
--- /dev/null
+++ b/fs/ceph/file.c
@@ -0,0 +1,2530 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/ceph/ceph_debug.h>
+#include <linux/ceph/striper.h>
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/file.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/writeback.h>
+#include <linux/falloc.h>
+#include <linux/iversion.h>
+#include <linux/ktime.h>
+
+#include "super.h"
+#include "mds_client.h"
+#include "cache.h"
+#include "io.h"
+#include "metric.h"
+
+static __le32 ceph_flags_sys2wire(u32 flags)
+{
+	u32 wire_flags = 0;
+
+	switch (flags & O_ACCMODE) {
+	case O_RDONLY:
+		wire_flags |= CEPH_O_RDONLY;
+		break;
+	case O_WRONLY:
+		wire_flags |= CEPH_O_WRONLY;
+		break;
+	case O_RDWR:
+		wire_flags |= CEPH_O_RDWR;
+		break;
+	}
+
+	flags &= ~O_ACCMODE;
+
+#define ceph_sys2wire(a) if (flags & a) { wire_flags |= CEPH_##a; flags &= ~a; }
+
+	ceph_sys2wire(O_CREAT);
+	ceph_sys2wire(O_EXCL);
+	ceph_sys2wire(O_TRUNC);
+	ceph_sys2wire(O_DIRECTORY);
+	ceph_sys2wire(O_NOFOLLOW);
+
+#undef ceph_sys2wire
+
+	if (flags)
+		dout("unused open flags: %x\n", flags);
+
+	return cpu_to_le32(wire_flags);
+}
+
+/*
+ * Ceph file operations
+ *
+ * Implement basic open/close functionality, and implement
+ * read/write.
+ *
+ * We implement three modes of file I/O:
+ *  - buffered uses the generic_file_aio_{read,write} helpers
+ *
+ *  - synchronous is used when there is multi-client read/write
+ *    sharing, avoids the page cache, and synchronously waits for an
+ *    ack from the OSD.
+ *
+ *  - direct io takes the variant of the sync path that references
+ *    user pages directly.
+ *
+ * fsync() flushes and waits on dirty pages, but just queues metadata
+ * for writeback: since the MDS can recover size and mtime there is no
+ * need to wait for MDS acknowledgement.
+ */
+
+/*
+ * How many pages to get in one call to iov_iter_get_pages().  This
+ * determines the size of the on-stack array used as a buffer.
+ */
+#define ITER_GET_BVECS_PAGES	64
+
+static ssize_t __iter_get_bvecs(struct iov_iter *iter, size_t maxsize,
+				struct bio_vec *bvecs)
+{
+	size_t size = 0;
+	int bvec_idx = 0;
+
+	if (maxsize > iov_iter_count(iter))
+		maxsize = iov_iter_count(iter);
+
+	while (size < maxsize) {
+		struct page *pages[ITER_GET_BVECS_PAGES];
+		ssize_t bytes;
+		size_t start;
+		int idx = 0;
+
+		bytes = iov_iter_get_pages(iter, pages, maxsize - size,
+					   ITER_GET_BVECS_PAGES, &start);
+		if (bytes < 0)
+			return size ?: bytes;
+
+		iov_iter_advance(iter, bytes);
+		size += bytes;
+
+		for ( ; bytes; idx++, bvec_idx++) {
+			struct bio_vec bv = {
+				.bv_page = pages[idx],
+				.bv_len = min_t(int, bytes, PAGE_SIZE - start),
+				.bv_offset = start,
+			};
+
+			bvecs[bvec_idx] = bv;
+			bytes -= bv.bv_len;
+			start = 0;
+		}
+	}
+
+	return size;
+}
+
+/*
+ * iov_iter_get_pages() only considers one iov_iter segment, no matter
+ * what maxsize or maxpages are given.  For ITER_BVEC that is a single
+ * page.
+ *
+ * Attempt to get up to @maxsize bytes worth of pages from @iter.
+ * Return the number of bytes in the created bio_vec array, or an error.
+ */
+static ssize_t iter_get_bvecs_alloc(struct iov_iter *iter, size_t maxsize,
+				    struct bio_vec **bvecs, int *num_bvecs)
+{
+	struct bio_vec *bv;
+	size_t orig_count = iov_iter_count(iter);
+	ssize_t bytes;
+	int npages;
+
+	iov_iter_truncate(iter, maxsize);
+	npages = iov_iter_npages(iter, INT_MAX);
+	iov_iter_reexpand(iter, orig_count);
+
+	/*
+	 * __iter_get_bvecs() may populate only part of the array -- zero it
+	 * out.
+	 */
+	bv = kvmalloc_array(npages, sizeof(*bv), GFP_KERNEL | __GFP_ZERO);
+	if (!bv)
+		return -ENOMEM;
+
+	bytes = __iter_get_bvecs(iter, maxsize, bv);
+	if (bytes < 0) {
+		/*
+		 * No pages were pinned -- just free the array.
+		 */
+		kvfree(bv);
+		return bytes;
+	}
+
+	*bvecs = bv;
+	*num_bvecs = npages;
+	return bytes;
+}
+
+static void put_bvecs(struct bio_vec *bvecs, int num_bvecs, bool should_dirty)
+{
+	int i;
+
+	for (i = 0; i < num_bvecs; i++) {
+		if (bvecs[i].bv_page) {
+			if (should_dirty)
+				set_page_dirty_lock(bvecs[i].bv_page);
+			put_page(bvecs[i].bv_page);
+		}
+	}
+	kvfree(bvecs);
+}
+
+/*
+ * Prepare an open request.  Preallocate ceph_cap to avoid an
+ * inopportune ENOMEM later.
+ */
+static struct ceph_mds_request *
+prepare_open_request(struct super_block *sb, int flags, int create_mode)
+{
+	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(sb);
+	struct ceph_mds_request *req;
+	int want_auth = USE_ANY_MDS;
+	int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
+
+	if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
+		want_auth = USE_AUTH_MDS;
+
+	req = ceph_mdsc_create_request(mdsc, op, want_auth);
+	if (IS_ERR(req))
+		goto out;
+	req->r_fmode = ceph_flags_to_mode(flags);
+	req->r_args.open.flags = ceph_flags_sys2wire(flags);
+	req->r_args.open.mode = cpu_to_le32(create_mode);
+out:
+	return req;
+}
+
+static int ceph_init_file_info(struct inode *inode, struct file *file,
+					int fmode, bool isdir)
+{
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_file_info *fi;
+
+	dout("%s %p %p 0%o (%s)\n", __func__, inode, file,
+			inode->i_mode, isdir ? "dir" : "regular");
+	BUG_ON(inode->i_fop->release != ceph_release);
+
+	if (isdir) {
+		struct ceph_dir_file_info *dfi =
+			kmem_cache_zalloc(ceph_dir_file_cachep, GFP_KERNEL);
+		if (!dfi)
+			return -ENOMEM;
+
+		file->private_data = dfi;
+		fi = &dfi->file_info;
+		dfi->next_offset = 2;
+		dfi->readdir_cache_idx = -1;
+	} else {
+		fi = kmem_cache_zalloc(ceph_file_cachep, GFP_KERNEL);
+		if (!fi)
+			return -ENOMEM;
+
+		file->private_data = fi;
+	}
+
+	ceph_get_fmode(ci, fmode, 1);
+	fi->fmode = fmode;
+
+	spin_lock_init(&fi->rw_contexts_lock);
+	INIT_LIST_HEAD(&fi->rw_contexts);
+	fi->filp_gen = READ_ONCE(ceph_inode_to_client(inode)->filp_gen);
+
+	return 0;
+}
+
+/*
+ * initialize private struct file data.
+ * if we fail, clean up by dropping fmode reference on the ceph_inode
+ */
+static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
+{
+	int ret = 0;
+
+	switch (inode->i_mode & S_IFMT) {
+	case S_IFREG:
+		ceph_fscache_register_inode_cookie(inode);
+		ceph_fscache_file_set_cookie(inode, file);
+		fallthrough;
+	case S_IFDIR:
+		ret = ceph_init_file_info(inode, file, fmode,
+						S_ISDIR(inode->i_mode));
+		break;
+
+	case S_IFLNK:
+		dout("init_file %p %p 0%o (symlink)\n", inode, file,
+		     inode->i_mode);
+		break;
+
+	default:
+		dout("init_file %p %p 0%o (special)\n", inode, file,
+		     inode->i_mode);
+		/*
+		 * we need to drop the open ref now, since we don't
+		 * have .release set to ceph_release.
+		 */
+		BUG_ON(inode->i_fop->release == ceph_release);
+
+		/* call the proper open fop */
+		ret = inode->i_fop->open(inode, file);
+	}
+	return ret;
+}
+
+/*
+ * try renew caps after session gets killed.
+ */
+int ceph_renew_caps(struct inode *inode, int fmode)
+{
+	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(inode->i_sb);
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_mds_request *req;
+	int err, flags, wanted;
+
+	spin_lock(&ci->i_ceph_lock);
+	__ceph_touch_fmode(ci, mdsc, fmode);
+	wanted = __ceph_caps_file_wanted(ci);
+	if (__ceph_is_any_real_caps(ci) &&
+	    (!(wanted & CEPH_CAP_ANY_WR) || ci->i_auth_cap)) {
+		int issued = __ceph_caps_issued(ci, NULL);
+		spin_unlock(&ci->i_ceph_lock);
+		dout("renew caps %p want %s issued %s updating mds_wanted\n",
+		     inode, ceph_cap_string(wanted), ceph_cap_string(issued));
+		ceph_check_caps(ci, 0, NULL);
+		return 0;
+	}
+	spin_unlock(&ci->i_ceph_lock);
+
+	flags = 0;
+	if ((wanted & CEPH_CAP_FILE_RD) && (wanted & CEPH_CAP_FILE_WR))
+		flags = O_RDWR;
+	else if (wanted & CEPH_CAP_FILE_RD)
+		flags = O_RDONLY;
+	else if (wanted & CEPH_CAP_FILE_WR)
+		flags = O_WRONLY;
+#ifdef O_LAZY
+	if (wanted & CEPH_CAP_FILE_LAZYIO)
+		flags |= O_LAZY;
+#endif
+
+	req = prepare_open_request(inode->i_sb, flags, 0);
+	if (IS_ERR(req)) {
+		err = PTR_ERR(req);
+		goto out;
+	}
+
+	req->r_inode = inode;
+	ihold(inode);
+	req->r_num_caps = 1;
+
+	err = ceph_mdsc_do_request(mdsc, NULL, req);
+	ceph_mdsc_put_request(req);
+out:
+	dout("renew caps %p open result=%d\n", inode, err);
+	return err < 0 ? err : 0;
+}
+
+/*
+ * If we already have the requisite capabilities, we can satisfy
+ * the open request locally (no need to request new caps from the
+ * MDS).  We do, however, need to inform the MDS (asynchronously)
+ * if our wanted caps set expands.
+ */
+int ceph_open(struct inode *inode, struct file *file)
+{
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
+	struct ceph_mds_client *mdsc = fsc->mdsc;
+	struct ceph_mds_request *req;
+	struct ceph_file_info *fi = file->private_data;
+	int err;
+	int flags, fmode, wanted;
+
+	if (fi) {
+		dout("open file %p is already opened\n", file);
+		return 0;
+	}
+
+	/* filter out O_CREAT|O_EXCL; vfs did that already.  yuck. */
+	flags = file->f_flags & ~(O_CREAT|O_EXCL);
+	if (S_ISDIR(inode->i_mode))
+		flags = O_DIRECTORY;  /* mds likes to know */
+
+	dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
+	     ceph_vinop(inode), file, flags, file->f_flags);
+	fmode = ceph_flags_to_mode(flags);
+	wanted = ceph_caps_for_mode(fmode);
+
+	/* snapped files are read-only */
+	if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
+		return -EROFS;
+
+	/* trivially open snapdir */
+	if (ceph_snap(inode) == CEPH_SNAPDIR) {
+		return ceph_init_file(inode, file, fmode);
+	}
+
+	/*
+	 * No need to block if we have caps on the auth MDS (for
+	 * write) or any MDS (for read).  Update wanted set
+	 * asynchronously.
+	 */
+	spin_lock(&ci->i_ceph_lock);
+	if (__ceph_is_any_real_caps(ci) &&
+	    (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
+		int mds_wanted = __ceph_caps_mds_wanted(ci, true);
+		int issued = __ceph_caps_issued(ci, NULL);
+
+		dout("open %p fmode %d want %s issued %s using existing\n",
+		     inode, fmode, ceph_cap_string(wanted),
+		     ceph_cap_string(issued));
+		__ceph_touch_fmode(ci, mdsc, fmode);
+		spin_unlock(&ci->i_ceph_lock);
+
+		/* adjust wanted? */
+		if ((issued & wanted) != wanted &&
+		    (mds_wanted & wanted) != wanted &&
+		    ceph_snap(inode) != CEPH_SNAPDIR)
+			ceph_check_caps(ci, 0, NULL);
+
+		return ceph_init_file(inode, file, fmode);
+	} else if (ceph_snap(inode) != CEPH_NOSNAP &&
+		   (ci->i_snap_caps & wanted) == wanted) {
+		__ceph_touch_fmode(ci, mdsc, fmode);
+		spin_unlock(&ci->i_ceph_lock);
+		return ceph_init_file(inode, file, fmode);
+	}
+
+	spin_unlock(&ci->i_ceph_lock);
+
+	dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
+	req = prepare_open_request(inode->i_sb, flags, 0);
+	if (IS_ERR(req)) {
+		err = PTR_ERR(req);
+		goto out;
+	}
+	req->r_inode = inode;
+	ihold(inode);
+
+	req->r_num_caps = 1;
+	err = ceph_mdsc_do_request(mdsc, NULL, req);
+	if (!err)
+		err = ceph_init_file(inode, file, req->r_fmode);
+	ceph_mdsc_put_request(req);
+	dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
+out:
+	return err;
+}
+
+/* Clone the layout from a synchronous create, if the dir now has Dc caps */
+static void
+cache_file_layout(struct inode *dst, struct inode *src)
+{
+	struct ceph_inode_info *cdst = ceph_inode(dst);
+	struct ceph_inode_info *csrc = ceph_inode(src);
+
+	spin_lock(&cdst->i_ceph_lock);
+	if ((__ceph_caps_issued(cdst, NULL) & CEPH_CAP_DIR_CREATE) &&
+	    !ceph_file_layout_is_valid(&cdst->i_cached_layout)) {
+		memcpy(&cdst->i_cached_layout, &csrc->i_layout,
+			sizeof(cdst->i_cached_layout));
+		rcu_assign_pointer(cdst->i_cached_layout.pool_ns,
+				   ceph_try_get_string(csrc->i_layout.pool_ns));
+	}
+	spin_unlock(&cdst->i_ceph_lock);
+}
+
+/*
+ * Try to set up an async create. We need caps, a file layout, and inode number,
+ * and either a lease on the dentry or complete dir info. If any of those
+ * criteria are not satisfied, then return false and the caller can go
+ * synchronous.
+ */
+static int try_prep_async_create(struct inode *dir, struct dentry *dentry,
+				 struct ceph_file_layout *lo, u64 *pino)
+{
+	struct ceph_inode_info *ci = ceph_inode(dir);
+	struct ceph_dentry_info *di = ceph_dentry(dentry);
+	int got = 0, want = CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE;
+	u64 ino;
+
+	spin_lock(&ci->i_ceph_lock);
+	/* No auth cap means no chance for Dc caps */
+	if (!ci->i_auth_cap)
+		goto no_async;
+
+	/* Any delegated inos? */
+	if (xa_empty(&ci->i_auth_cap->session->s_delegated_inos))
+		goto no_async;
+
+	if (!ceph_file_layout_is_valid(&ci->i_cached_layout))
+		goto no_async;
+
+	if ((__ceph_caps_issued(ci, NULL) & want) != want)
+		goto no_async;
+
+	if (d_in_lookup(dentry)) {
+		if (!__ceph_dir_is_complete(ci))
+			goto no_async;
+		spin_lock(&dentry->d_lock);
+		di->lease_shared_gen = atomic_read(&ci->i_shared_gen);
+		spin_unlock(&dentry->d_lock);
+	} else if (atomic_read(&ci->i_shared_gen) !=
+		   READ_ONCE(di->lease_shared_gen)) {
+		goto no_async;
+	}
+
+	ino = ceph_get_deleg_ino(ci->i_auth_cap->session);
+	if (!ino)
+		goto no_async;
+
+	*pino = ino;
+	ceph_take_cap_refs(ci, want, false);
+	memcpy(lo, &ci->i_cached_layout, sizeof(*lo));
+	rcu_assign_pointer(lo->pool_ns,
+			   ceph_try_get_string(ci->i_cached_layout.pool_ns));
+	got = want;
+no_async:
+	spin_unlock(&ci->i_ceph_lock);
+	return got;
+}
+
+static void restore_deleg_ino(struct inode *dir, u64 ino)
+{
+	struct ceph_inode_info *ci = ceph_inode(dir);
+	struct ceph_mds_session *s = NULL;
+
+	spin_lock(&ci->i_ceph_lock);
+	if (ci->i_auth_cap)
+		s = ceph_get_mds_session(ci->i_auth_cap->session);
+	spin_unlock(&ci->i_ceph_lock);
+	if (s) {
+		int err = ceph_restore_deleg_ino(s, ino);
+		if (err)
+			pr_warn("ceph: unable to restore delegated ino 0x%llx to session: %d\n",
+				ino, err);
+		ceph_put_mds_session(s);
+	}
+}
+
+static void ceph_async_create_cb(struct ceph_mds_client *mdsc,
+                                 struct ceph_mds_request *req)
+{
+	int result = req->r_err ? req->r_err :
+			le32_to_cpu(req->r_reply_info.head->result);
+
+	if (result == -EJUKEBOX)
+		goto out;
+
+	mapping_set_error(req->r_parent->i_mapping, result);
+
+	if (result) {
+		struct dentry *dentry = req->r_dentry;
+		int pathlen = 0;
+		u64 base = 0;
+		char *path = ceph_mdsc_build_path(req->r_dentry, &pathlen,
+						  &base, 0);
+
+		ceph_dir_clear_complete(req->r_parent);
+		if (!d_unhashed(dentry))
+			d_drop(dentry);
+
+		/* FIXME: start returning I/O errors on all accesses? */
+		pr_warn("ceph: async create failure path=(%llx)%s result=%d!\n",
+			base, IS_ERR(path) ? "<<bad>>" : path, result);
+		ceph_mdsc_free_path(path, pathlen);
+	}
+
+	if (req->r_target_inode) {
+		struct ceph_inode_info *ci = ceph_inode(req->r_target_inode);
+		u64 ino = ceph_vino(req->r_target_inode).ino;
+
+		if (req->r_deleg_ino != ino)
+			pr_warn("%s: inode number mismatch! err=%d deleg_ino=0x%llx target=0x%llx\n",
+				__func__, req->r_err, req->r_deleg_ino, ino);
+		mapping_set_error(req->r_target_inode->i_mapping, result);
+
+		spin_lock(&ci->i_ceph_lock);
+		if (ci->i_ceph_flags & CEPH_I_ASYNC_CREATE) {
+			ci->i_ceph_flags &= ~CEPH_I_ASYNC_CREATE;
+			wake_up_bit(&ci->i_ceph_flags, CEPH_ASYNC_CREATE_BIT);
+		}
+		ceph_kick_flushing_inode_caps(req->r_session, ci);
+		spin_unlock(&ci->i_ceph_lock);
+	} else {
+		pr_warn("%s: no req->r_target_inode for 0x%llx\n", __func__,
+			req->r_deleg_ino);
+	}
+out:
+	ceph_mdsc_release_dir_caps(req);
+}
+
+static int ceph_finish_async_create(struct inode *dir, struct dentry *dentry,
+				    struct file *file, umode_t mode,
+				    struct ceph_mds_request *req,
+				    struct ceph_acl_sec_ctx *as_ctx,
+				    struct ceph_file_layout *lo)
+{
+	int ret;
+	char xattr_buf[4];
+	struct ceph_mds_reply_inode in = { };
+	struct ceph_mds_reply_info_in iinfo = { .in = &in };
+	struct ceph_inode_info *ci = ceph_inode(dir);
+	struct inode *inode;
+	struct timespec64 now;
+	struct ceph_string *pool_ns;
+	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
+	struct ceph_vino vino = { .ino = req->r_deleg_ino,
+				  .snap = CEPH_NOSNAP };
+
+	ktime_get_real_ts64(&now);
+
+	inode = ceph_get_inode(dentry->d_sb, vino);
+	if (IS_ERR(inode))
+		return PTR_ERR(inode);
+
+	iinfo.inline_version = CEPH_INLINE_NONE;
+	iinfo.change_attr = 1;
+	ceph_encode_timespec64(&iinfo.btime, &now);
+
+	if (req->r_pagelist) {
+		iinfo.xattr_len = req->r_pagelist->length;
+		iinfo.xattr_data = req->r_pagelist->mapped_tail;
+	} else {
+		/* fake it */
+		iinfo.xattr_len = ARRAY_SIZE(xattr_buf);
+		iinfo.xattr_data = xattr_buf;
+		memset(iinfo.xattr_data, 0, iinfo.xattr_len);
+	}
+
+	in.ino = cpu_to_le64(vino.ino);
+	in.snapid = cpu_to_le64(CEPH_NOSNAP);
+	in.version = cpu_to_le64(1);	// ???
+	in.cap.caps = in.cap.wanted = cpu_to_le32(CEPH_CAP_ALL_FILE);
+	in.cap.cap_id = cpu_to_le64(1);
+	in.cap.realm = cpu_to_le64(ci->i_snap_realm->ino);
+	in.cap.flags = CEPH_CAP_FLAG_AUTH;
+	in.ctime = in.mtime = in.atime = iinfo.btime;
+	in.truncate_seq = cpu_to_le32(1);
+	in.truncate_size = cpu_to_le64(-1ULL);
+	in.xattr_version = cpu_to_le64(1);
+	in.uid = cpu_to_le32(from_kuid(&init_user_ns, current_fsuid()));
+	if (dir->i_mode & S_ISGID) {
+		in.gid = cpu_to_le32(from_kgid(&init_user_ns, dir->i_gid));
+
+		/* Directories always inherit the setgid bit. */
+		if (S_ISDIR(mode))
+			mode |= S_ISGID;
+		else if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP) &&
+			 !in_group_p(dir->i_gid) &&
+			 !capable_wrt_inode_uidgid(dir, CAP_FSETID))
+			mode &= ~S_ISGID;
+	} else {
+		in.gid = cpu_to_le32(from_kgid(&init_user_ns, current_fsgid()));
+	}
+	in.mode = cpu_to_le32((u32)mode);
+
+	in.nlink = cpu_to_le32(1);
+	in.max_size = cpu_to_le64(lo->stripe_unit);
+
+	ceph_file_layout_to_legacy(lo, &in.layout);
+	/* lo is private, so pool_ns can't change */
+	pool_ns = rcu_dereference_raw(lo->pool_ns);
+	if (pool_ns) {
+		iinfo.pool_ns_len = pool_ns->len;
+		iinfo.pool_ns_data = pool_ns->str;
+	}
+
+	down_read(&mdsc->snap_rwsem);
+	ret = ceph_fill_inode(inode, NULL, &iinfo, NULL, req->r_session,
+			      req->r_fmode, NULL);
+	up_read(&mdsc->snap_rwsem);
+	if (ret) {
+		dout("%s failed to fill inode: %d\n", __func__, ret);
+		ceph_dir_clear_complete(dir);
+		if (!d_unhashed(dentry))
+			d_drop(dentry);
+		if (inode->i_state & I_NEW)
+			discard_new_inode(inode);
+	} else {
+		struct dentry *dn;
+
+		dout("%s d_adding new inode 0x%llx to 0x%llx/%s\n", __func__,
+			vino.ino, ceph_ino(dir), dentry->d_name.name);
+		ceph_dir_clear_ordered(dir);
+		ceph_init_inode_acls(inode, as_ctx);
+		if (inode->i_state & I_NEW) {
+			/*
+			 * If it's not I_NEW, then someone created this before
+			 * we got here. Assume the server is aware of it at
+			 * that point and don't worry about setting
+			 * CEPH_I_ASYNC_CREATE.
+			 */
+			ceph_inode(inode)->i_ceph_flags = CEPH_I_ASYNC_CREATE;
+			unlock_new_inode(inode);
+		}
+		if (d_in_lookup(dentry) || d_really_is_negative(dentry)) {
+			if (!d_unhashed(dentry))
+				d_drop(dentry);
+			dn = d_splice_alias(inode, dentry);
+			WARN_ON_ONCE(dn && dn != dentry);
+		}
+		file->f_mode |= FMODE_CREATED;
+		ret = finish_open(file, dentry, ceph_open);
+	}
+	return ret;
+}
+
+/*
+ * Do a lookup + open with a single request.  If we get a non-existent
+ * file or symlink, return 1 so the VFS can retry.
+ */
+int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
+		     struct file *file, unsigned flags, umode_t mode)
+{
+	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
+	struct ceph_mds_client *mdsc = fsc->mdsc;
+	struct ceph_mds_request *req;
+	struct dentry *dn;
+	struct ceph_acl_sec_ctx as_ctx = {};
+	bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS);
+	int mask;
+	int err;
+
+	dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
+	     dir, dentry, dentry,
+	     d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
+
+	if (dentry->d_name.len > NAME_MAX)
+		return -ENAMETOOLONG;
+
+	/*
+	 * Do not truncate the file, since atomic_open is called before the
+	 * permission check. The caller will do the truncation afterward.
+	 */
+	flags &= ~O_TRUNC;
+
+	if (flags & O_CREAT) {
+		if (ceph_quota_is_max_files_exceeded(dir))
+			return -EDQUOT;
+		err = ceph_pre_init_acls(dir, &mode, &as_ctx);
+		if (err < 0)
+			return err;
+		err = ceph_security_init_secctx(dentry, mode, &as_ctx);
+		if (err < 0)
+			goto out_ctx;
+		/* Async create can't handle more than a page of xattrs */
+		if (as_ctx.pagelist &&
+		    !list_is_singular(&as_ctx.pagelist->head))
+			try_async = false;
+	} else if (!d_in_lookup(dentry)) {
+		/* If it's not being looked up, it's negative */
+		return -ENOENT;
+	}
+retry:
+	/* do the open */
+	req = prepare_open_request(dir->i_sb, flags, mode);
+	if (IS_ERR(req)) {
+		err = PTR_ERR(req);
+		goto out_ctx;
+	}
+	req->r_dentry = dget(dentry);
+	req->r_num_caps = 2;
+	mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
+	if (ceph_security_xattr_wanted(dir))
+		mask |= CEPH_CAP_XATTR_SHARED;
+	req->r_args.open.mask = cpu_to_le32(mask);
+	req->r_parent = dir;
+
+	if (flags & O_CREAT) {
+		struct ceph_file_layout lo;
+
+		req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
+		req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
+		if (as_ctx.pagelist) {
+			req->r_pagelist = as_ctx.pagelist;
+			as_ctx.pagelist = NULL;
+		}
+		if (try_async &&
+		    (req->r_dir_caps =
+		      try_prep_async_create(dir, dentry, &lo,
+					    &req->r_deleg_ino))) {
+			set_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags);
+			req->r_args.open.flags |= cpu_to_le32(CEPH_O_EXCL);
+			req->r_callback = ceph_async_create_cb;
+			err = ceph_mdsc_submit_request(mdsc, dir, req);
+			if (!err) {
+				err = ceph_finish_async_create(dir, dentry,
+							file, mode, req,
+							&as_ctx, &lo);
+			} else if (err == -EJUKEBOX) {
+				restore_deleg_ino(dir, req->r_deleg_ino);
+				ceph_mdsc_put_request(req);
+				try_async = false;
+				ceph_put_string(rcu_dereference_raw(lo.pool_ns));
+				goto retry;
+			}
+			ceph_put_string(rcu_dereference_raw(lo.pool_ns));
+			goto out_req;
+		}
+	}
+
+	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
+	err = ceph_mdsc_do_request(mdsc, (flags & O_CREAT) ? dir : NULL, req);
+	err = ceph_handle_snapdir(req, dentry, err);
+	if (err)
+		goto out_req;
+
+	if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
+		err = ceph_handle_notrace_create(dir, dentry);
+
+	if (d_in_lookup(dentry)) {
+		dn = ceph_finish_lookup(req, dentry, err);
+		if (IS_ERR(dn))
+			err = PTR_ERR(dn);
+	} else {
+		/* we were given a hashed negative dentry */
+		dn = NULL;
+	}
+	if (err)
+		goto out_req;
+	if (dn || d_really_is_negative(dentry) || d_is_symlink(dentry)) {
+		/* make vfs retry on splice, ENOENT, or symlink */
+		dout("atomic_open finish_no_open on dn %p\n", dn);
+		err = finish_no_open(file, dn);
+	} else {
+		dout("atomic_open finish_open on dn %p\n", dn);
+		if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
+			struct inode *newino = d_inode(dentry);
+
+			cache_file_layout(dir, newino);
+			ceph_init_inode_acls(newino, &as_ctx);
+			file->f_mode |= FMODE_CREATED;
+		}
+		err = finish_open(file, dentry, ceph_open);
+	}
+out_req:
+	ceph_mdsc_put_request(req);
+out_ctx:
+	ceph_release_acl_sec_ctx(&as_ctx);
+	dout("atomic_open result=%d\n", err);
+	return err;
+}
+
+int ceph_release(struct inode *inode, struct file *file)
+{
+	struct ceph_inode_info *ci = ceph_inode(inode);
+
+	if (S_ISDIR(inode->i_mode)) {
+		struct ceph_dir_file_info *dfi = file->private_data;
+		dout("release inode %p dir file %p\n", inode, file);
+		WARN_ON(!list_empty(&dfi->file_info.rw_contexts));
+
+		ceph_put_fmode(ci, dfi->file_info.fmode, 1);
+
+		if (dfi->last_readdir)
+			ceph_mdsc_put_request(dfi->last_readdir);
+		kfree(dfi->last_name);
+		kfree(dfi->dir_info);
+		kmem_cache_free(ceph_dir_file_cachep, dfi);
+	} else {
+		struct ceph_file_info *fi = file->private_data;
+		dout("release inode %p regular file %p\n", inode, file);
+		WARN_ON(!list_empty(&fi->rw_contexts));
+
+		ceph_put_fmode(ci, fi->fmode, 1);
+
+		kmem_cache_free(ceph_file_cachep, fi);
+	}
+
+	/* wake up anyone waiting for caps on this inode */
+	wake_up_all(&ci->i_cap_wq);
+	return 0;
+}
+
+enum {
+	HAVE_RETRIED = 1,
+	CHECK_EOF =    2,
+	READ_INLINE =  3,
+};
+
+/*
+ * Completely synchronous read and write methods.  Direct from __user
+ * buffer to osd, or directly to user pages (if O_DIRECT).
+ *
+ * If the read spans object boundary, just do multiple reads.  (That's not
+ * atomic, but good enough for now.)
+ *
+ * If we get a short result from the OSD, check against i_size; we need to
+ * only return a short read to the caller if we hit EOF.
+ */
+static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to,
+			      int *retry_op)
+{
+	struct file *file = iocb->ki_filp;
+	struct inode *inode = file_inode(file);
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+	struct ceph_osd_client *osdc = &fsc->client->osdc;
+	ssize_t ret;
+	u64 off = iocb->ki_pos;
+	u64 len = iov_iter_count(to);
+
+	dout("sync_read on file %p %llu~%u %s\n", file, off, (unsigned)len,
+	     (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
+
+	if (!len)
+		return 0;
+	/*
+	 * flush any page cache pages in this range.  this
+	 * will make concurrent normal and sync io slow,
+	 * but it will at least behave sensibly when they are
+	 * in sequence.
+	 */
+	ret = filemap_write_and_wait_range(inode->i_mapping,
+					   off, off + len - 1);
+	if (ret < 0)
+		return ret;
+
+	ret = 0;
+	while ((len = iov_iter_count(to)) > 0) {
+		struct ceph_osd_request *req;
+		struct page **pages;
+		int num_pages;
+		size_t page_off;
+		u64 i_size;
+		bool more;
+		int idx;
+		size_t left;
+
+		req = ceph_osdc_new_request(osdc, &ci->i_layout,
+					ci->i_vino, off, &len, 0, 1,
+					CEPH_OSD_OP_READ, CEPH_OSD_FLAG_READ,
+					NULL, ci->i_truncate_seq,
+					ci->i_truncate_size, false);
+		if (IS_ERR(req)) {
+			ret = PTR_ERR(req);
+			break;
+		}
+
+		more = len < iov_iter_count(to);
+
+		num_pages = calc_pages_for(off, len);
+		page_off = off & ~PAGE_MASK;
+		pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
+		if (IS_ERR(pages)) {
+			ceph_osdc_put_request(req);
+			ret = PTR_ERR(pages);
+			break;
+		}
+
+		osd_req_op_extent_osd_data_pages(req, 0, pages, len, page_off,
+						 false, false);
+		ret = ceph_osdc_start_request(osdc, req, false);
+		if (!ret)
+			ret = ceph_osdc_wait_request(osdc, req);
+
+		ceph_update_read_latency(&fsc->mdsc->metric,
+					 req->r_start_latency,
+					 req->r_end_latency,
+					 ret);
+
+		ceph_osdc_put_request(req);
+
+		i_size = i_size_read(inode);
+		dout("sync_read %llu~%llu got %zd i_size %llu%s\n",
+		     off, len, ret, i_size, (more ? " MORE" : ""));
+
+		if (ret == -ENOENT)
+			ret = 0;
+		if (ret >= 0 && ret < len && (off + ret < i_size)) {
+			int zlen = min(len - ret, i_size - off - ret);
+			int zoff = page_off + ret;
+			dout("sync_read zero gap %llu~%llu\n",
+                             off + ret, off + ret + zlen);
+			ceph_zero_page_vector_range(zoff, zlen, pages);
+			ret += zlen;
+		}
+
+		idx = 0;
+		left = ret > 0 ? ret : 0;
+		while (left > 0) {
+			size_t len, copied;
+			page_off = off & ~PAGE_MASK;
+			len = min_t(size_t, left, PAGE_SIZE - page_off);
+			SetPageUptodate(pages[idx]);
+			copied = copy_page_to_iter(pages[idx++],
+						   page_off, len, to);
+			off += copied;
+			left -= copied;
+			if (copied < len) {
+				ret = -EFAULT;
+				break;
+			}
+		}
+		ceph_release_page_vector(pages, num_pages);
+
+		if (ret < 0) {
+			if (ret == -EBLOCKLISTED)
+				fsc->blocklisted = true;
+			break;
+		}
+
+		if (off >= i_size || !more)
+			break;
+	}
+
+	if (off > iocb->ki_pos) {
+		if (ret >= 0 &&
+		    iov_iter_count(to) > 0 && off >= i_size_read(inode))
+			*retry_op = CHECK_EOF;
+		ret = off - iocb->ki_pos;
+		iocb->ki_pos = off;
+	}
+
+	dout("sync_read result %zd retry_op %d\n", ret, *retry_op);
+	return ret;
+}
+
+struct ceph_aio_request {
+	struct kiocb *iocb;
+	size_t total_len;
+	bool write;
+	bool should_dirty;
+	int error;
+	struct list_head osd_reqs;
+	unsigned num_reqs;
+	atomic_t pending_reqs;
+	struct timespec64 mtime;
+	struct ceph_cap_flush *prealloc_cf;
+};
+
+struct ceph_aio_work {
+	struct work_struct work;
+	struct ceph_osd_request *req;
+};
+
+static void ceph_aio_retry_work(struct work_struct *work);
+
+static void ceph_aio_complete(struct inode *inode,
+			      struct ceph_aio_request *aio_req)
+{
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	int ret;
+
+	if (!atomic_dec_and_test(&aio_req->pending_reqs))
+		return;
+
+	if (aio_req->iocb->ki_flags & IOCB_DIRECT)
+		inode_dio_end(inode);
+
+	ret = aio_req->error;
+	if (!ret)
+		ret = aio_req->total_len;
+
+	dout("ceph_aio_complete %p rc %d\n", inode, ret);
+
+	if (ret >= 0 && aio_req->write) {
+		int dirty;
+
+		loff_t endoff = aio_req->iocb->ki_pos + aio_req->total_len;
+		if (endoff > i_size_read(inode)) {
+			if (ceph_inode_set_size(inode, endoff))
+				ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
+		}
+
+		spin_lock(&ci->i_ceph_lock);
+		ci->i_inline_version = CEPH_INLINE_NONE;
+		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
+					       &aio_req->prealloc_cf);
+		spin_unlock(&ci->i_ceph_lock);
+		if (dirty)
+			__mark_inode_dirty(inode, dirty);
+
+	}
+
+	ceph_put_cap_refs(ci, (aio_req->write ? CEPH_CAP_FILE_WR :
+						CEPH_CAP_FILE_RD));
+
+	aio_req->iocb->ki_complete(aio_req->iocb, ret, 0);
+
+	ceph_free_cap_flush(aio_req->prealloc_cf);
+	kfree(aio_req);
+}
+
+static void ceph_aio_complete_req(struct ceph_osd_request *req)
+{
+	int rc = req->r_result;
+	struct inode *inode = req->r_inode;
+	struct ceph_aio_request *aio_req = req->r_priv;
+	struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
+	struct ceph_client_metric *metric = &ceph_sb_to_mdsc(inode->i_sb)->metric;
+
+	BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_BVECS);
+	BUG_ON(!osd_data->num_bvecs);
+
+	dout("ceph_aio_complete_req %p rc %d bytes %u\n",
+	     inode, rc, osd_data->bvec_pos.iter.bi_size);
+
+	/* r_start_latency == 0 means the request was not submitted */
+	if (req->r_start_latency) {
+		if (aio_req->write)
+			ceph_update_write_latency(metric, req->r_start_latency,
+						  req->r_end_latency, rc);
+		else
+			ceph_update_read_latency(metric, req->r_start_latency,
+						 req->r_end_latency, rc);
+	}
+
+	if (rc == -EOLDSNAPC) {
+		struct ceph_aio_work *aio_work;
+		BUG_ON(!aio_req->write);
+
+		aio_work = kmalloc(sizeof(*aio_work), GFP_NOFS);
+		if (aio_work) {
+			INIT_WORK(&aio_work->work, ceph_aio_retry_work);
+			aio_work->req = req;
+			queue_work(ceph_inode_to_client(inode)->inode_wq,
+				   &aio_work->work);
+			return;
+		}
+		rc = -ENOMEM;
+	} else if (!aio_req->write) {
+		if (rc == -ENOENT)
+			rc = 0;
+		if (rc >= 0 && osd_data->bvec_pos.iter.bi_size > rc) {
+			struct iov_iter i;
+			int zlen = osd_data->bvec_pos.iter.bi_size - rc;
+
+			/*
+			 * If read is satisfied by single OSD request,
+			 * it can pass EOF. Otherwise read is within
+			 * i_size.
+			 */
+			if (aio_req->num_reqs == 1) {
+				loff_t i_size = i_size_read(inode);
+				loff_t endoff = aio_req->iocb->ki_pos + rc;
+				if (endoff < i_size)
+					zlen = min_t(size_t, zlen,
+						     i_size - endoff);
+				aio_req->total_len = rc + zlen;
+			}
+
+			iov_iter_bvec(&i, READ, osd_data->bvec_pos.bvecs,
+				      osd_data->num_bvecs,
+				      osd_data->bvec_pos.iter.bi_size);
+			iov_iter_advance(&i, rc);
+			iov_iter_zero(zlen, &i);
+		}
+	}
+
+	put_bvecs(osd_data->bvec_pos.bvecs, osd_data->num_bvecs,
+		  aio_req->should_dirty);
+	ceph_osdc_put_request(req);
+
+	if (rc < 0)
+		cmpxchg(&aio_req->error, 0, rc);
+
+	ceph_aio_complete(inode, aio_req);
+	return;
+}
+
+static void ceph_aio_retry_work(struct work_struct *work)
+{
+	struct ceph_aio_work *aio_work =
+		container_of(work, struct ceph_aio_work, work);
+	struct ceph_osd_request *orig_req = aio_work->req;
+	struct ceph_aio_request *aio_req = orig_req->r_priv;
+	struct inode *inode = orig_req->r_inode;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_snap_context *snapc;
+	struct ceph_osd_request *req;
+	int ret;
+
+	spin_lock(&ci->i_ceph_lock);
+	if (__ceph_have_pending_cap_snap(ci)) {
+		struct ceph_cap_snap *capsnap =
+			list_last_entry(&ci->i_cap_snaps,
+					struct ceph_cap_snap,
+					ci_item);
+		snapc = ceph_get_snap_context(capsnap->context);
+	} else {
+		BUG_ON(!ci->i_head_snapc);
+		snapc = ceph_get_snap_context(ci->i_head_snapc);
+	}
+	spin_unlock(&ci->i_ceph_lock);
+
+	req = ceph_osdc_alloc_request(orig_req->r_osdc, snapc, 1,
+			false, GFP_NOFS);
+	if (!req) {
+		ret = -ENOMEM;
+		req = orig_req;
+		goto out;
+	}
+
+	req->r_flags = /* CEPH_OSD_FLAG_ORDERSNAP | */ CEPH_OSD_FLAG_WRITE;
+	ceph_oloc_copy(&req->r_base_oloc, &orig_req->r_base_oloc);
+	ceph_oid_copy(&req->r_base_oid, &orig_req->r_base_oid);
+
+	req->r_ops[0] = orig_req->r_ops[0];
+
+	req->r_mtime = aio_req->mtime;
+	req->r_data_offset = req->r_ops[0].extent.offset;
+
+	ret = ceph_osdc_alloc_messages(req, GFP_NOFS);
+	if (ret) {
+		ceph_osdc_put_request(req);
+		req = orig_req;
+		goto out;
+	}
+
+	ceph_osdc_put_request(orig_req);
+
+	req->r_callback = ceph_aio_complete_req;
+	req->r_inode = inode;
+	req->r_priv = aio_req;
+
+	ret = ceph_osdc_start_request(req->r_osdc, req, false);
+out:
+	if (ret < 0) {
+		req->r_result = ret;
+		ceph_aio_complete_req(req);
+	}
+
+	ceph_put_snap_context(snapc);
+	kfree(aio_work);
+}
+
+static ssize_t
+ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
+		       struct ceph_snap_context *snapc,
+		       struct ceph_cap_flush **pcf)
+{
+	struct file *file = iocb->ki_filp;
+	struct inode *inode = file_inode(file);
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+	struct ceph_client_metric *metric = &fsc->mdsc->metric;
+	struct ceph_vino vino;
+	struct ceph_osd_request *req;
+	struct bio_vec *bvecs;
+	struct ceph_aio_request *aio_req = NULL;
+	int num_pages = 0;
+	int flags;
+	int ret = 0;
+	struct timespec64 mtime = current_time(inode);
+	size_t count = iov_iter_count(iter);
+	loff_t pos = iocb->ki_pos;
+	bool write = iov_iter_rw(iter) == WRITE;
+	bool should_dirty = !write && iter_is_iovec(iter);
+
+	if (write && ceph_snap(file_inode(file)) != CEPH_NOSNAP)
+		return -EROFS;
+
+	dout("sync_direct_%s on file %p %lld~%u snapc %p seq %lld\n",
+	     (write ? "write" : "read"), file, pos, (unsigned)count,
+	     snapc, snapc ? snapc->seq : 0);
+
+	if (write) {
+		int ret2 = invalidate_inode_pages2_range(inode->i_mapping,
+					pos >> PAGE_SHIFT,
+					(pos + count - 1) >> PAGE_SHIFT);
+		if (ret2 < 0)
+			dout("invalidate_inode_pages2_range returned %d\n", ret2);
+
+		flags = /* CEPH_OSD_FLAG_ORDERSNAP | */ CEPH_OSD_FLAG_WRITE;
+	} else {
+		flags = CEPH_OSD_FLAG_READ;
+	}
+
+	while (iov_iter_count(iter) > 0) {
+		u64 size = iov_iter_count(iter);
+		ssize_t len;
+
+		if (write)
+			size = min_t(u64, size, fsc->mount_options->wsize);
+		else
+			size = min_t(u64, size, fsc->mount_options->rsize);
+
+		vino = ceph_vino(inode);
+		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
+					    vino, pos, &size, 0,
+					    1,
+					    write ? CEPH_OSD_OP_WRITE :
+						    CEPH_OSD_OP_READ,
+					    flags, snapc,
+					    ci->i_truncate_seq,
+					    ci->i_truncate_size,
+					    false);
+		if (IS_ERR(req)) {
+			ret = PTR_ERR(req);
+			break;
+		}
+
+		len = iter_get_bvecs_alloc(iter, size, &bvecs, &num_pages);
+		if (len < 0) {
+			ceph_osdc_put_request(req);
+			ret = len;
+			break;
+		}
+		if (len != size)
+			osd_req_op_extent_update(req, 0, len);
+
+		/*
+		 * To simplify error handling, allow AIO when IO within i_size
+		 * or IO can be satisfied by single OSD request.
+		 */
+		if (pos == iocb->ki_pos && !is_sync_kiocb(iocb) &&
+		    (len == count || pos + count <= i_size_read(inode))) {
+			aio_req = kzalloc(sizeof(*aio_req), GFP_KERNEL);
+			if (aio_req) {
+				aio_req->iocb = iocb;
+				aio_req->write = write;
+				aio_req->should_dirty = should_dirty;
+				INIT_LIST_HEAD(&aio_req->osd_reqs);
+				if (write) {
+					aio_req->mtime = mtime;
+					swap(aio_req->prealloc_cf, *pcf);
+				}
+			}
+			/* ignore error */
+		}
+
+		if (write) {
+			/*
+			 * throw out any page cache pages in this range. this
+			 * may block.
+			 */
+			truncate_inode_pages_range(inode->i_mapping, pos,
+						   PAGE_ALIGN(pos + len) - 1);
+
+			req->r_mtime = mtime;
+		}
+
+		osd_req_op_extent_osd_data_bvecs(req, 0, bvecs, num_pages, len);
+
+		if (aio_req) {
+			aio_req->total_len += len;
+			aio_req->num_reqs++;
+			atomic_inc(&aio_req->pending_reqs);
+
+			req->r_callback = ceph_aio_complete_req;
+			req->r_inode = inode;
+			req->r_priv = aio_req;
+			list_add_tail(&req->r_private_item, &aio_req->osd_reqs);
+
+			pos += len;
+			continue;
+		}
+
+		ret = ceph_osdc_start_request(req->r_osdc, req, false);
+		if (!ret)
+			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
+
+		if (write)
+			ceph_update_write_latency(metric, req->r_start_latency,
+						  req->r_end_latency, ret);
+		else
+			ceph_update_read_latency(metric, req->r_start_latency,
+						 req->r_end_latency, ret);
+
+		size = i_size_read(inode);
+		if (!write) {
+			if (ret == -ENOENT)
+				ret = 0;
+			if (ret >= 0 && ret < len && pos + ret < size) {
+				struct iov_iter i;
+				int zlen = min_t(size_t, len - ret,
+						 size - pos - ret);
+
+				iov_iter_bvec(&i, READ, bvecs, num_pages, len);
+				iov_iter_advance(&i, ret);
+				iov_iter_zero(zlen, &i);
+				ret += zlen;
+			}
+			if (ret >= 0)
+				len = ret;
+		}
+
+		put_bvecs(bvecs, num_pages, should_dirty);
+		ceph_osdc_put_request(req);
+		if (ret < 0)
+			break;
+
+		pos += len;
+		if (!write && pos >= size)
+			break;
+
+		if (write && pos > size) {
+			if (ceph_inode_set_size(inode, pos))
+				ceph_check_caps(ceph_inode(inode),
+						CHECK_CAPS_AUTHONLY,
+						NULL);
+		}
+	}
+
+	if (aio_req) {
+		LIST_HEAD(osd_reqs);
+
+		if (aio_req->num_reqs == 0) {
+			kfree(aio_req);
+			return ret;
+		}
+
+		ceph_get_cap_refs(ci, write ? CEPH_CAP_FILE_WR :
+					      CEPH_CAP_FILE_RD);
+
+		list_splice(&aio_req->osd_reqs, &osd_reqs);
+		inode_dio_begin(inode);
+		while (!list_empty(&osd_reqs)) {
+			req = list_first_entry(&osd_reqs,
+					       struct ceph_osd_request,
+					       r_private_item);
+			list_del_init(&req->r_private_item);
+			if (ret >= 0)
+				ret = ceph_osdc_start_request(req->r_osdc,
+							      req, false);
+			if (ret < 0) {
+				req->r_result = ret;
+				ceph_aio_complete_req(req);
+			}
+		}
+		return -EIOCBQUEUED;
+	}
+
+	if (ret != -EOLDSNAPC && pos > iocb->ki_pos) {
+		ret = pos - iocb->ki_pos;
+		iocb->ki_pos = pos;
+	}
+	return ret;
+}
+
+/*
+ * Synchronous write, straight from __user pointer or user pages.
+ *
+ * If write spans object boundary, just do multiple writes.  (For a
+ * correct atomic write, we should e.g. take write locks on all
+ * objects, rollback on failure, etc.)
+ */
+static ssize_t
+ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos,
+		struct ceph_snap_context *snapc)
+{
+	struct file *file = iocb->ki_filp;
+	struct inode *inode = file_inode(file);
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+	struct ceph_vino vino;
+	struct ceph_osd_request *req;
+	struct page **pages;
+	u64 len;
+	int num_pages;
+	int written = 0;
+	int flags;
+	int ret;
+	bool check_caps = false;
+	struct timespec64 mtime = current_time(inode);
+	size_t count = iov_iter_count(from);
+
+	if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
+		return -EROFS;
+
+	dout("sync_write on file %p %lld~%u snapc %p seq %lld\n",
+	     file, pos, (unsigned)count, snapc, snapc->seq);
+
+	ret = filemap_write_and_wait_range(inode->i_mapping,
+					   pos, pos + count - 1);
+	if (ret < 0)
+		return ret;
+
+	ret = invalidate_inode_pages2_range(inode->i_mapping,
+					    pos >> PAGE_SHIFT,
+					    (pos + count - 1) >> PAGE_SHIFT);
+	if (ret < 0)
+		dout("invalidate_inode_pages2_range returned %d\n", ret);
+
+	flags = /* CEPH_OSD_FLAG_ORDERSNAP | */ CEPH_OSD_FLAG_WRITE;
+
+	while ((len = iov_iter_count(from)) > 0) {
+		size_t left;
+		int n;
+
+		vino = ceph_vino(inode);
+		req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
+					    vino, pos, &len, 0, 1,
+					    CEPH_OSD_OP_WRITE, flags, snapc,
+					    ci->i_truncate_seq,
+					    ci->i_truncate_size,
+					    false);
+		if (IS_ERR(req)) {
+			ret = PTR_ERR(req);
+			break;
+		}
+
+		/*
+		 * write from beginning of first page,
+		 * regardless of io alignment
+		 */
+		num_pages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+
+		pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
+		if (IS_ERR(pages)) {
+			ret = PTR_ERR(pages);
+			goto out;
+		}
+
+		left = len;
+		for (n = 0; n < num_pages; n++) {
+			size_t plen = min_t(size_t, left, PAGE_SIZE);
+			ret = copy_page_from_iter(pages[n], 0, plen, from);
+			if (ret != plen) {
+				ret = -EFAULT;
+				break;
+			}
+			left -= ret;
+		}
+
+		if (ret < 0) {
+			ceph_release_page_vector(pages, num_pages);
+			goto out;
+		}
+
+		req->r_inode = inode;
+
+		osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
+						false, true);
+
+		req->r_mtime = mtime;
+		ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
+		if (!ret)
+			ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
+
+		ceph_update_write_latency(&fsc->mdsc->metric, req->r_start_latency,
+					  req->r_end_latency, ret);
+out:
+		ceph_osdc_put_request(req);
+		if (ret != 0) {
+			ceph_set_error_write(ci);
+			break;
+		}
+
+		ceph_clear_error_write(ci);
+		pos += len;
+		written += len;
+		if (pos > i_size_read(inode)) {
+			check_caps = ceph_inode_set_size(inode, pos);
+			if (check_caps)
+				ceph_check_caps(ceph_inode(inode),
+						CHECK_CAPS_AUTHONLY,
+						NULL);
+		}
+
+	}
+
+	if (ret != -EOLDSNAPC && written > 0) {
+		ret = written;
+		iocb->ki_pos = pos;
+	}
+	return ret;
+}
+
+/*
+ * Wrap generic_file_aio_read with checks for cap bits on the inode.
+ * Atomically grab references, so that those bits are not released
+ * back to the MDS mid-read.
+ *
+ * Hmm, the sync read case isn't actually async... should it be?
+ */
+static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+	struct file *filp = iocb->ki_filp;
+	struct ceph_file_info *fi = filp->private_data;
+	size_t len = iov_iter_count(to);
+	struct inode *inode = file_inode(filp);
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct page *pinned_page = NULL;
+	bool direct_lock = iocb->ki_flags & IOCB_DIRECT;
+	ssize_t ret;
+	int want, got = 0;
+	int retry_op = 0, read = 0;
+
+again:
+	dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
+	     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
+
+	if (direct_lock)
+		ceph_start_io_direct(inode);
+	else
+		ceph_start_io_read(inode);
+
+	if (fi->fmode & CEPH_FILE_MODE_LAZY)
+		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
+	else
+		want = CEPH_CAP_FILE_CACHE;
+	ret = ceph_get_caps(filp, CEPH_CAP_FILE_RD, want, -1,
+			    &got, &pinned_page);
+	if (ret < 0) {
+		if (iocb->ki_flags & IOCB_DIRECT)
+			ceph_end_io_direct(inode);
+		else
+			ceph_end_io_read(inode);
+		return ret;
+	}
+
+	if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
+	    (iocb->ki_flags & IOCB_DIRECT) ||
+	    (fi->flags & CEPH_F_SYNC)) {
+
+		dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
+		     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
+		     ceph_cap_string(got));
+
+		if (ci->i_inline_version == CEPH_INLINE_NONE) {
+			if (!retry_op && (iocb->ki_flags & IOCB_DIRECT)) {
+				ret = ceph_direct_read_write(iocb, to,
+							     NULL, NULL);
+				if (ret >= 0 && ret < len)
+					retry_op = CHECK_EOF;
+			} else {
+				ret = ceph_sync_read(iocb, to, &retry_op);
+			}
+		} else {
+			retry_op = READ_INLINE;
+		}
+	} else {
+		CEPH_DEFINE_RW_CONTEXT(rw_ctx, got);
+		dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
+		     inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
+		     ceph_cap_string(got));
+		ceph_add_rw_context(fi, &rw_ctx);
+		ret = generic_file_read_iter(iocb, to);
+		ceph_del_rw_context(fi, &rw_ctx);
+	}
+
+	dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
+	     inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
+	if (pinned_page) {
+		put_page(pinned_page);
+		pinned_page = NULL;
+	}
+	ceph_put_cap_refs(ci, got);
+
+	if (direct_lock)
+		ceph_end_io_direct(inode);
+	else
+		ceph_end_io_read(inode);
+
+	if (retry_op > HAVE_RETRIED && ret >= 0) {
+		int statret;
+		struct page *page = NULL;
+		loff_t i_size;
+		if (retry_op == READ_INLINE) {
+			page = __page_cache_alloc(GFP_KERNEL);
+			if (!page)
+				return -ENOMEM;
+		}
+
+		statret = __ceph_do_getattr(inode, page,
+					    CEPH_STAT_CAP_INLINE_DATA, !!page);
+		if (statret < 0) {
+			if (page)
+				__free_page(page);
+			if (statret == -ENODATA) {
+				BUG_ON(retry_op != READ_INLINE);
+				goto again;
+			}
+			return statret;
+		}
+
+		i_size = i_size_read(inode);
+		if (retry_op == READ_INLINE) {
+			BUG_ON(ret > 0 || read > 0);
+			if (iocb->ki_pos < i_size &&
+			    iocb->ki_pos < PAGE_SIZE) {
+				loff_t end = min_t(loff_t, i_size,
+						   iocb->ki_pos + len);
+				end = min_t(loff_t, end, PAGE_SIZE);
+				if (statret < end)
+					zero_user_segment(page, statret, end);
+				ret = copy_page_to_iter(page,
+						iocb->ki_pos & ~PAGE_MASK,
+						end - iocb->ki_pos, to);
+				iocb->ki_pos += ret;
+				read += ret;
+			}
+			if (iocb->ki_pos < i_size && read < len) {
+				size_t zlen = min_t(size_t, len - read,
+						    i_size - iocb->ki_pos);
+				ret = iov_iter_zero(zlen, to);
+				iocb->ki_pos += ret;
+				read += ret;
+			}
+			__free_pages(page, 0);
+			return read;
+		}
+
+		/* hit EOF or hole? */
+		if (retry_op == CHECK_EOF && iocb->ki_pos < i_size &&
+		    ret < len) {
+			dout("sync_read hit hole, ppos %lld < size %lld"
+			     ", reading more\n", iocb->ki_pos, i_size);
+
+			read += ret;
+			len -= ret;
+			retry_op = HAVE_RETRIED;
+			goto again;
+		}
+	}
+
+	if (ret >= 0)
+		ret += read;
+
+	return ret;
+}
+
+/*
+ * Take cap references to avoid releasing caps to MDS mid-write.
+ *
+ * If we are synchronous, and write with an old snap context, the OSD
+ * may return EOLDSNAPC.  In that case, retry the write.. _after_
+ * dropping our cap refs and allowing the pending snap to logically
+ * complete _before_ this write occurs.
+ *
+ * If we are near ENOSPC, write synchronously.
+ */
+static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+	struct file *file = iocb->ki_filp;
+	struct ceph_file_info *fi = file->private_data;
+	struct inode *inode = file_inode(file);
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+	struct ceph_osd_client *osdc = &fsc->client->osdc;
+	struct ceph_cap_flush *prealloc_cf;
+	ssize_t count, written = 0;
+	int err, want, got;
+	bool direct_lock = false;
+	u32 map_flags;
+	u64 pool_flags;
+	loff_t pos;
+	loff_t limit = max(i_size_read(inode), fsc->max_file_size);
+
+	if (ceph_snap(inode) != CEPH_NOSNAP)
+		return -EROFS;
+
+	prealloc_cf = ceph_alloc_cap_flush();
+	if (!prealloc_cf)
+		return -ENOMEM;
+
+	if ((iocb->ki_flags & (IOCB_DIRECT | IOCB_APPEND)) == IOCB_DIRECT)
+		direct_lock = true;
+
+retry_snap:
+	if (direct_lock)
+		ceph_start_io_direct(inode);
+	else
+		ceph_start_io_write(inode);
+
+	/* We can write back this queue in page reclaim */
+	current->backing_dev_info = inode_to_bdi(inode);
+
+	if (iocb->ki_flags & IOCB_APPEND) {
+		err = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
+		if (err < 0)
+			goto out;
+	}
+
+	err = generic_write_checks(iocb, from);
+	if (err <= 0)
+		goto out;
+
+	pos = iocb->ki_pos;
+	if (unlikely(pos >= limit)) {
+		err = -EFBIG;
+		goto out;
+	} else {
+		iov_iter_truncate(from, limit - pos);
+	}
+
+	count = iov_iter_count(from);
+	if (ceph_quota_is_max_bytes_exceeded(inode, pos + count)) {
+		err = -EDQUOT;
+		goto out;
+	}
+
+	down_read(&osdc->lock);
+	map_flags = osdc->osdmap->flags;
+	pool_flags = ceph_pg_pool_flags(osdc->osdmap, ci->i_layout.pool_id);
+	up_read(&osdc->lock);
+	if ((map_flags & CEPH_OSDMAP_FULL) ||
+	    (pool_flags & CEPH_POOL_FLAG_FULL)) {
+		err = -ENOSPC;
+		goto out;
+	}
+
+	err = file_remove_privs(file);
+	if (err)
+		goto out;
+
+	if (ci->i_inline_version != CEPH_INLINE_NONE) {
+		err = ceph_uninline_data(file, NULL);
+		if (err < 0)
+			goto out;
+	}
+
+	dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
+	     inode, ceph_vinop(inode), pos, count, i_size_read(inode));
+	if (fi->fmode & CEPH_FILE_MODE_LAZY)
+		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
+	else
+		want = CEPH_CAP_FILE_BUFFER;
+	got = 0;
+	err = ceph_get_caps(file, CEPH_CAP_FILE_WR, want, pos + count,
+			    &got, NULL);
+	if (err < 0)
+		goto out;
+
+	err = file_update_time(file);
+	if (err)
+		goto out_caps;
+
+	inode_inc_iversion_raw(inode);
+
+	dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
+	     inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
+
+	if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
+	    (iocb->ki_flags & IOCB_DIRECT) || (fi->flags & CEPH_F_SYNC) ||
+	    (ci->i_ceph_flags & CEPH_I_ERROR_WRITE)) {
+		struct ceph_snap_context *snapc;
+		struct iov_iter data;
+
+		spin_lock(&ci->i_ceph_lock);
+		if (__ceph_have_pending_cap_snap(ci)) {
+			struct ceph_cap_snap *capsnap =
+					list_last_entry(&ci->i_cap_snaps,
+							struct ceph_cap_snap,
+							ci_item);
+			snapc = ceph_get_snap_context(capsnap->context);
+		} else {
+			BUG_ON(!ci->i_head_snapc);
+			snapc = ceph_get_snap_context(ci->i_head_snapc);
+		}
+		spin_unlock(&ci->i_ceph_lock);
+
+		/* we might need to revert back to that point */
+		data = *from;
+		if (iocb->ki_flags & IOCB_DIRECT)
+			written = ceph_direct_read_write(iocb, &data, snapc,
+							 &prealloc_cf);
+		else
+			written = ceph_sync_write(iocb, &data, pos, snapc);
+		if (direct_lock)
+			ceph_end_io_direct(inode);
+		else
+			ceph_end_io_write(inode);
+		if (written > 0)
+			iov_iter_advance(from, written);
+		ceph_put_snap_context(snapc);
+	} else {
+		/*
+		 * No need to acquire the i_truncate_mutex. Because
+		 * the MDS revokes Fwb caps before sending truncate
+		 * message to us. We can't get Fwb cap while there
+		 * are pending vmtruncate. So write and vmtruncate
+		 * can not run at the same time
+		 */
+		written = generic_perform_write(file, from, pos);
+		if (likely(written >= 0))
+			iocb->ki_pos = pos + written;
+		ceph_end_io_write(inode);
+	}
+
+	if (written >= 0) {
+		int dirty;
+
+		spin_lock(&ci->i_ceph_lock);
+		ci->i_inline_version = CEPH_INLINE_NONE;
+		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
+					       &prealloc_cf);
+		spin_unlock(&ci->i_ceph_lock);
+		if (dirty)
+			__mark_inode_dirty(inode, dirty);
+		if (ceph_quota_is_max_bytes_approaching(inode, iocb->ki_pos))
+			ceph_check_caps(ci, 0, NULL);
+	}
+
+	dout("aio_write %p %llx.%llx %llu~%u  dropping cap refs on %s\n",
+	     inode, ceph_vinop(inode), pos, (unsigned)count,
+	     ceph_cap_string(got));
+	ceph_put_cap_refs(ci, got);
+
+	if (written == -EOLDSNAPC) {
+		dout("aio_write %p %llx.%llx %llu~%u" "got EOLDSNAPC, retrying\n",
+		     inode, ceph_vinop(inode), pos, (unsigned)count);
+		goto retry_snap;
+	}
+
+	if (written >= 0) {
+		if ((map_flags & CEPH_OSDMAP_NEARFULL) ||
+		    (pool_flags & CEPH_POOL_FLAG_NEARFULL))
+			iocb->ki_flags |= IOCB_DSYNC;
+		written = generic_write_sync(iocb, written);
+	}
+
+	goto out_unlocked;
+out_caps:
+	ceph_put_cap_refs(ci, got);
+out:
+	if (direct_lock)
+		ceph_end_io_direct(inode);
+	else
+		ceph_end_io_write(inode);
+out_unlocked:
+	ceph_free_cap_flush(prealloc_cf);
+	current->backing_dev_info = NULL;
+	return written ? written : err;
+}
+
+/*
+ * llseek.  be sure to verify file size on SEEK_END.
+ */
+static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
+{
+	struct inode *inode = file->f_mapping->host;
+	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+	loff_t i_size;
+	loff_t ret;
+
+	inode_lock(inode);
+
+	if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
+		ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
+		if (ret < 0)
+			goto out;
+	}
+
+	i_size = i_size_read(inode);
+	switch (whence) {
+	case SEEK_END:
+		offset += i_size;
+		break;
+	case SEEK_CUR:
+		/*
+		 * Here we special-case the lseek(fd, 0, SEEK_CUR)
+		 * position-querying operation.  Avoid rewriting the "same"
+		 * f_pos value back to the file because a concurrent read(),
+		 * write() or lseek() might have altered it
+		 */
+		if (offset == 0) {
+			ret = file->f_pos;
+			goto out;
+		}
+		offset += file->f_pos;
+		break;
+	case SEEK_DATA:
+		if (offset < 0 || offset >= i_size) {
+			ret = -ENXIO;
+			goto out;
+		}
+		break;
+	case SEEK_HOLE:
+		if (offset < 0 || offset >= i_size) {
+			ret = -ENXIO;
+			goto out;
+		}
+		offset = i_size;
+		break;
+	}
+
+	ret = vfs_setpos(file, offset, max(i_size, fsc->max_file_size));
+
+out:
+	inode_unlock(inode);
+	return ret;
+}
+
+static inline void ceph_zero_partial_page(
+	struct inode *inode, loff_t offset, unsigned size)
+{
+	struct page *page;
+	pgoff_t index = offset >> PAGE_SHIFT;
+
+	page = find_lock_page(inode->i_mapping, index);
+	if (page) {
+		wait_on_page_writeback(page);
+		zero_user(page, offset & (PAGE_SIZE - 1), size);
+		unlock_page(page);
+		put_page(page);
+	}
+}
+
+static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
+				      loff_t length)
+{
+	loff_t nearly = round_up(offset, PAGE_SIZE);
+	if (offset < nearly) {
+		loff_t size = nearly - offset;
+		if (length < size)
+			size = length;
+		ceph_zero_partial_page(inode, offset, size);
+		offset += size;
+		length -= size;
+	}
+	if (length >= PAGE_SIZE) {
+		loff_t size = round_down(length, PAGE_SIZE);
+		truncate_pagecache_range(inode, offset, offset + size - 1);
+		offset += size;
+		length -= size;
+	}
+	if (length)
+		ceph_zero_partial_page(inode, offset, length);
+}
+
+static int ceph_zero_partial_object(struct inode *inode,
+				    loff_t offset, loff_t *length)
+{
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+	struct ceph_osd_request *req;
+	int ret = 0;
+	loff_t zero = 0;
+	int op;
+
+	if (!length) {
+		op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
+		length = &zero;
+	} else {
+		op = CEPH_OSD_OP_ZERO;
+	}
+
+	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
+					ceph_vino(inode),
+					offset, length,
+					0, 1, op,
+					CEPH_OSD_FLAG_WRITE,
+					NULL, 0, 0, false);
+	if (IS_ERR(req)) {
+		ret = PTR_ERR(req);
+		goto out;
+	}
+
+	req->r_mtime = inode->i_mtime;
+	ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
+	if (!ret) {
+		ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
+		if (ret == -ENOENT)
+			ret = 0;
+	}
+	ceph_osdc_put_request(req);
+
+out:
+	return ret;
+}
+
+static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
+{
+	int ret = 0;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	s32 stripe_unit = ci->i_layout.stripe_unit;
+	s32 stripe_count = ci->i_layout.stripe_count;
+	s32 object_size = ci->i_layout.object_size;
+	u64 object_set_size = object_size * stripe_count;
+	u64 nearly, t;
+
+	/* round offset up to next period boundary */
+	nearly = offset + object_set_size - 1;
+	t = nearly;
+	nearly -= do_div(t, object_set_size);
+
+	while (length && offset < nearly) {
+		loff_t size = length;
+		ret = ceph_zero_partial_object(inode, offset, &size);
+		if (ret < 0)
+			return ret;
+		offset += size;
+		length -= size;
+	}
+	while (length >= object_set_size) {
+		int i;
+		loff_t pos = offset;
+		for (i = 0; i < stripe_count; ++i) {
+			ret = ceph_zero_partial_object(inode, pos, NULL);
+			if (ret < 0)
+				return ret;
+			pos += stripe_unit;
+		}
+		offset += object_set_size;
+		length -= object_set_size;
+	}
+	while (length) {
+		loff_t size = length;
+		ret = ceph_zero_partial_object(inode, offset, &size);
+		if (ret < 0)
+			return ret;
+		offset += size;
+		length -= size;
+	}
+	return ret;
+}
+
+static long ceph_fallocate(struct file *file, int mode,
+				loff_t offset, loff_t length)
+{
+	struct ceph_file_info *fi = file->private_data;
+	struct inode *inode = file_inode(file);
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_cap_flush *prealloc_cf;
+	int want, got = 0;
+	int dirty;
+	int ret = 0;
+	loff_t endoff = 0;
+	loff_t size;
+
+	if (mode != (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
+		return -EOPNOTSUPP;
+
+	if (!S_ISREG(inode->i_mode))
+		return -EOPNOTSUPP;
+
+	prealloc_cf = ceph_alloc_cap_flush();
+	if (!prealloc_cf)
+		return -ENOMEM;
+
+	inode_lock(inode);
+
+	if (ceph_snap(inode) != CEPH_NOSNAP) {
+		ret = -EROFS;
+		goto unlock;
+	}
+
+	if (ci->i_inline_version != CEPH_INLINE_NONE) {
+		ret = ceph_uninline_data(file, NULL);
+		if (ret < 0)
+			goto unlock;
+	}
+
+	size = i_size_read(inode);
+
+	/* Are we punching a hole beyond EOF? */
+	if (offset >= size)
+		goto unlock;
+	if ((offset + length) > size)
+		length = size - offset;
+
+	if (fi->fmode & CEPH_FILE_MODE_LAZY)
+		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
+	else
+		want = CEPH_CAP_FILE_BUFFER;
+
+	ret = ceph_get_caps(file, CEPH_CAP_FILE_WR, want, endoff, &got, NULL);
+	if (ret < 0)
+		goto unlock;
+
+	ceph_zero_pagecache_range(inode, offset, length);
+	ret = ceph_zero_objects(inode, offset, length);
+
+	if (!ret) {
+		spin_lock(&ci->i_ceph_lock);
+		ci->i_inline_version = CEPH_INLINE_NONE;
+		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
+					       &prealloc_cf);
+		spin_unlock(&ci->i_ceph_lock);
+		if (dirty)
+			__mark_inode_dirty(inode, dirty);
+	}
+
+	ceph_put_cap_refs(ci, got);
+unlock:
+	inode_unlock(inode);
+	ceph_free_cap_flush(prealloc_cf);
+	return ret;
+}
+
+/*
+ * This function tries to get FILE_WR capabilities for dst_ci and FILE_RD for
+ * src_ci.  Two attempts are made to obtain both caps, and an error is return if
+ * this fails; zero is returned on success.
+ */
+static int get_rd_wr_caps(struct file *src_filp, int *src_got,
+			  struct file *dst_filp,
+			  loff_t dst_endoff, int *dst_got)
+{
+	int ret = 0;
+	bool retrying = false;
+
+retry_caps:
+	ret = ceph_get_caps(dst_filp, CEPH_CAP_FILE_WR, CEPH_CAP_FILE_BUFFER,
+			    dst_endoff, dst_got, NULL);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * Since we're already holding the FILE_WR capability for the dst file,
+	 * we would risk a deadlock by using ceph_get_caps.  Thus, we'll do some
+	 * retry dance instead to try to get both capabilities.
+	 */
+	ret = ceph_try_get_caps(file_inode(src_filp),
+				CEPH_CAP_FILE_RD, CEPH_CAP_FILE_SHARED,
+				false, src_got);
+	if (ret <= 0) {
+		/* Start by dropping dst_ci caps and getting src_ci caps */
+		ceph_put_cap_refs(ceph_inode(file_inode(dst_filp)), *dst_got);
+		if (retrying) {
+			if (!ret)
+				/* ceph_try_get_caps masks EAGAIN */
+				ret = -EAGAIN;
+			return ret;
+		}
+		ret = ceph_get_caps(src_filp, CEPH_CAP_FILE_RD,
+				    CEPH_CAP_FILE_SHARED, -1, src_got, NULL);
+		if (ret < 0)
+			return ret;
+		/*... drop src_ci caps too, and retry */
+		ceph_put_cap_refs(ceph_inode(file_inode(src_filp)), *src_got);
+		retrying = true;
+		goto retry_caps;
+	}
+	return ret;
+}
+
+static void put_rd_wr_caps(struct ceph_inode_info *src_ci, int src_got,
+			   struct ceph_inode_info *dst_ci, int dst_got)
+{
+	ceph_put_cap_refs(src_ci, src_got);
+	ceph_put_cap_refs(dst_ci, dst_got);
+}
+
+/*
+ * This function does several size-related checks, returning an error if:
+ *  - source file is smaller than off+len
+ *  - destination file size is not OK (inode_newsize_ok())
+ *  - max bytes quotas is exceeded
+ */
+static int is_file_size_ok(struct inode *src_inode, struct inode *dst_inode,
+			   loff_t src_off, loff_t dst_off, size_t len)
+{
+	loff_t size, endoff;
+
+	size = i_size_read(src_inode);
+	/*
+	 * Don't copy beyond source file EOF.  Instead of simply setting length
+	 * to (size - src_off), just drop to VFS default implementation, as the
+	 * local i_size may be stale due to other clients writing to the source
+	 * inode.
+	 */
+	if (src_off + len > size) {
+		dout("Copy beyond EOF (%llu + %zu > %llu)\n",
+		     src_off, len, size);
+		return -EOPNOTSUPP;
+	}
+	size = i_size_read(dst_inode);
+
+	endoff = dst_off + len;
+	if (inode_newsize_ok(dst_inode, endoff))
+		return -EOPNOTSUPP;
+
+	if (ceph_quota_is_max_bytes_exceeded(dst_inode, endoff))
+		return -EDQUOT;
+
+	return 0;
+}
+
+static ssize_t ceph_do_objects_copy(struct ceph_inode_info *src_ci, u64 *src_off,
+				    struct ceph_inode_info *dst_ci, u64 *dst_off,
+				    struct ceph_fs_client *fsc,
+				    size_t len, unsigned int flags)
+{
+	struct ceph_object_locator src_oloc, dst_oloc;
+	struct ceph_object_id src_oid, dst_oid;
+	size_t bytes = 0;
+	u64 src_objnum, src_objoff, dst_objnum, dst_objoff;
+	u32 src_objlen, dst_objlen;
+	u32 object_size = src_ci->i_layout.object_size;
+	int ret;
+
+	src_oloc.pool = src_ci->i_layout.pool_id;
+	src_oloc.pool_ns = ceph_try_get_string(src_ci->i_layout.pool_ns);
+	dst_oloc.pool = dst_ci->i_layout.pool_id;
+	dst_oloc.pool_ns = ceph_try_get_string(dst_ci->i_layout.pool_ns);
+
+	while (len >= object_size) {
+		ceph_calc_file_object_mapping(&src_ci->i_layout, *src_off,
+					      object_size, &src_objnum,
+					      &src_objoff, &src_objlen);
+		ceph_calc_file_object_mapping(&dst_ci->i_layout, *dst_off,
+					      object_size, &dst_objnum,
+					      &dst_objoff, &dst_objlen);
+		ceph_oid_init(&src_oid);
+		ceph_oid_printf(&src_oid, "%llx.%08llx",
+				src_ci->i_vino.ino, src_objnum);
+		ceph_oid_init(&dst_oid);
+		ceph_oid_printf(&dst_oid, "%llx.%08llx",
+				dst_ci->i_vino.ino, dst_objnum);
+		/* Do an object remote copy */
+		ret = ceph_osdc_copy_from(&fsc->client->osdc,
+					  src_ci->i_vino.snap, 0,
+					  &src_oid, &src_oloc,
+					  CEPH_OSD_OP_FLAG_FADVISE_SEQUENTIAL |
+					  CEPH_OSD_OP_FLAG_FADVISE_NOCACHE,
+					  &dst_oid, &dst_oloc,
+					  CEPH_OSD_OP_FLAG_FADVISE_SEQUENTIAL |
+					  CEPH_OSD_OP_FLAG_FADVISE_DONTNEED,
+					  dst_ci->i_truncate_seq,
+					  dst_ci->i_truncate_size,
+					  CEPH_OSD_COPY_FROM_FLAG_TRUNCATE_SEQ);
+		if (ret) {
+			if (ret == -EOPNOTSUPP) {
+				fsc->have_copy_from2 = false;
+				pr_notice("OSDs don't support copy-from2; disabling copy offload\n");
+			}
+			dout("ceph_osdc_copy_from returned %d\n", ret);
+			if (!bytes)
+				bytes = ret;
+			goto out;
+		}
+		len -= object_size;
+		bytes += object_size;
+		*src_off += object_size;
+		*dst_off += object_size;
+	}
+
+out:
+	ceph_oloc_destroy(&src_oloc);
+	ceph_oloc_destroy(&dst_oloc);
+	return bytes;
+}
+
+static ssize_t __ceph_copy_file_range(struct file *src_file, loff_t src_off,
+				      struct file *dst_file, loff_t dst_off,
+				      size_t len, unsigned int flags)
+{
+	struct inode *src_inode = file_inode(src_file);
+	struct inode *dst_inode = file_inode(dst_file);
+	struct ceph_inode_info *src_ci = ceph_inode(src_inode);
+	struct ceph_inode_info *dst_ci = ceph_inode(dst_inode);
+	struct ceph_cap_flush *prealloc_cf;
+	struct ceph_fs_client *src_fsc = ceph_inode_to_client(src_inode);
+	loff_t size;
+	ssize_t ret = -EIO, bytes;
+	u64 src_objnum, dst_objnum, src_objoff, dst_objoff;
+	u32 src_objlen, dst_objlen;
+	int src_got = 0, dst_got = 0, err, dirty;
+
+	if (src_inode->i_sb != dst_inode->i_sb) {
+		struct ceph_fs_client *dst_fsc = ceph_inode_to_client(dst_inode);
+
+		if (ceph_fsid_compare(&src_fsc->client->fsid,
+				      &dst_fsc->client->fsid)) {
+			dout("Copying files across clusters: src: %pU dst: %pU\n",
+			     &src_fsc->client->fsid, &dst_fsc->client->fsid);
+			return -EXDEV;
+		}
+	}
+	if (ceph_snap(dst_inode) != CEPH_NOSNAP)
+		return -EROFS;
+
+	/*
+	 * Some of the checks below will return -EOPNOTSUPP, which will force a
+	 * fallback to the default VFS copy_file_range implementation.  This is
+	 * desirable in several cases (for ex, the 'len' is smaller than the
+	 * size of the objects, or in cases where that would be more
+	 * efficient).
+	 */
+
+	if (ceph_test_mount_opt(src_fsc, NOCOPYFROM))
+		return -EOPNOTSUPP;
+
+	if (!src_fsc->have_copy_from2)
+		return -EOPNOTSUPP;
+
+	/*
+	 * Striped file layouts require that we copy partial objects, but the
+	 * OSD copy-from operation only supports full-object copies.  Limit
+	 * this to non-striped file layouts for now.
+	 */
+	if ((src_ci->i_layout.stripe_unit != dst_ci->i_layout.stripe_unit) ||
+	    (src_ci->i_layout.stripe_count != 1) ||
+	    (dst_ci->i_layout.stripe_count != 1) ||
+	    (src_ci->i_layout.object_size != dst_ci->i_layout.object_size)) {
+		dout("Invalid src/dst files layout\n");
+		return -EOPNOTSUPP;
+	}
+
+	if (len < src_ci->i_layout.object_size)
+		return -EOPNOTSUPP; /* no remote copy will be done */
+
+	prealloc_cf = ceph_alloc_cap_flush();
+	if (!prealloc_cf)
+		return -ENOMEM;
+
+	/* Start by sync'ing the source and destination files */
+	ret = file_write_and_wait_range(src_file, src_off, (src_off + len));
+	if (ret < 0) {
+		dout("failed to write src file (%zd)\n", ret);
+		goto out;
+	}
+	ret = file_write_and_wait_range(dst_file, dst_off, (dst_off + len));
+	if (ret < 0) {
+		dout("failed to write dst file (%zd)\n", ret);
+		goto out;
+	}
+
+	/*
+	 * We need FILE_WR caps for dst_ci and FILE_RD for src_ci as other
+	 * clients may have dirty data in their caches.  And OSDs know nothing
+	 * about caps, so they can't safely do the remote object copies.
+	 */
+	err = get_rd_wr_caps(src_file, &src_got,
+			     dst_file, (dst_off + len), &dst_got);
+	if (err < 0) {
+		dout("get_rd_wr_caps returned %d\n", err);
+		ret = -EOPNOTSUPP;
+		goto out;
+	}
+
+	ret = is_file_size_ok(src_inode, dst_inode, src_off, dst_off, len);
+	if (ret < 0)
+		goto out_caps;
+
+	/* Drop dst file cached pages */
+	ret = invalidate_inode_pages2_range(dst_inode->i_mapping,
+					    dst_off >> PAGE_SHIFT,
+					    (dst_off + len) >> PAGE_SHIFT);
+	if (ret < 0) {
+		dout("Failed to invalidate inode pages (%zd)\n", ret);
+		ret = 0; /* XXX */
+	}
+	ceph_calc_file_object_mapping(&src_ci->i_layout, src_off,
+				      src_ci->i_layout.object_size,
+				      &src_objnum, &src_objoff, &src_objlen);
+	ceph_calc_file_object_mapping(&dst_ci->i_layout, dst_off,
+				      dst_ci->i_layout.object_size,
+				      &dst_objnum, &dst_objoff, &dst_objlen);
+	/* object-level offsets need to the same */
+	if (src_objoff != dst_objoff) {
+		ret = -EOPNOTSUPP;
+		goto out_caps;
+	}
+
+	/*
+	 * Do a manual copy if the object offset isn't object aligned.
+	 * 'src_objlen' contains the bytes left until the end of the object,
+	 * starting at the src_off
+	 */
+	if (src_objoff) {
+		dout("Initial partial copy of %u bytes\n", src_objlen);
+
+		/*
+		 * we need to temporarily drop all caps as we'll be calling
+		 * {read,write}_iter, which will get caps again.
+		 */
+		put_rd_wr_caps(src_ci, src_got, dst_ci, dst_got);
+		ret = do_splice_direct(src_file, &src_off, dst_file,
+				       &dst_off, src_objlen, flags);
+		/* Abort on short copies or on error */
+		if (ret < (long)src_objlen) {
+			dout("Failed partial copy (%zd)\n", ret);
+			goto out;
+		}
+		len -= ret;
+		err = get_rd_wr_caps(src_file, &src_got,
+				     dst_file, (dst_off + len), &dst_got);
+		if (err < 0)
+			goto out;
+		err = is_file_size_ok(src_inode, dst_inode,
+				      src_off, dst_off, len);
+		if (err < 0)
+			goto out_caps;
+	}
+
+	size = i_size_read(dst_inode);
+	bytes = ceph_do_objects_copy(src_ci, &src_off, dst_ci, &dst_off,
+				     src_fsc, len, flags);
+	if (bytes <= 0) {
+		if (!ret)
+			ret = bytes;
+		goto out_caps;
+	}
+	dout("Copied %zu bytes out of %zu\n", bytes, len);
+	len -= bytes;
+	ret += bytes;
+
+	file_update_time(dst_file);
+	inode_inc_iversion_raw(dst_inode);
+
+	if (dst_off > size) {
+		/* Let the MDS know about dst file size change */
+		if (ceph_inode_set_size(dst_inode, dst_off) ||
+		    ceph_quota_is_max_bytes_approaching(dst_inode, dst_off))
+			ceph_check_caps(dst_ci, CHECK_CAPS_AUTHONLY, NULL);
+	}
+	/* Mark Fw dirty */
+	spin_lock(&dst_ci->i_ceph_lock);
+	dst_ci->i_inline_version = CEPH_INLINE_NONE;
+	dirty = __ceph_mark_dirty_caps(dst_ci, CEPH_CAP_FILE_WR, &prealloc_cf);
+	spin_unlock(&dst_ci->i_ceph_lock);
+	if (dirty)
+		__mark_inode_dirty(dst_inode, dirty);
+
+out_caps:
+	put_rd_wr_caps(src_ci, src_got, dst_ci, dst_got);
+
+	/*
+	 * Do the final manual copy if we still have some bytes left, unless
+	 * there were errors in remote object copies (len >= object_size).
+	 */
+	if (len && (len < src_ci->i_layout.object_size)) {
+		dout("Final partial copy of %zu bytes\n", len);
+		bytes = do_splice_direct(src_file, &src_off, dst_file,
+					 &dst_off, len, flags);
+		if (bytes > 0)
+			ret += bytes;
+		else
+			dout("Failed partial copy (%zd)\n", bytes);
+	}
+
+out:
+	ceph_free_cap_flush(prealloc_cf);
+
+	return ret;
+}
+
+static ssize_t ceph_copy_file_range(struct file *src_file, loff_t src_off,
+				    struct file *dst_file, loff_t dst_off,
+				    size_t len, unsigned int flags)
+{
+	ssize_t ret;
+
+	ret = __ceph_copy_file_range(src_file, src_off, dst_file, dst_off,
+				     len, flags);
+
+	if (ret == -EOPNOTSUPP || ret == -EXDEV)
+		ret = generic_copy_file_range(src_file, src_off, dst_file,
+					      dst_off, len, flags);
+	return ret;
+}
+
+const struct file_operations ceph_file_fops = {
+	.open = ceph_open,
+	.release = ceph_release,
+	.llseek = ceph_llseek,
+	.read_iter = ceph_read_iter,
+	.write_iter = ceph_write_iter,
+	.mmap = ceph_mmap,
+	.fsync = ceph_fsync,
+	.lock = ceph_lock,
+	.setlease = simple_nosetlease,
+	.flock = ceph_flock,
+	.splice_read = generic_file_splice_read,
+	.splice_write = iter_file_splice_write,
+	.unlocked_ioctl = ceph_ioctl,
+	.compat_ioctl = compat_ptr_ioctl,
+	.fallocate	= ceph_fallocate,
+	.copy_file_range = ceph_copy_file_range,
+};