From 222b7f90ba3825728fd27e9105aeee7af9576819 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Thu, 23 Nov 2017 17:47:15 +0800
Subject: ceph: voluntarily drop Ax cap for requests that create new inode

MDS need to rdlock directory inode's authlock when handling these
requests. Voluntarily dropping CEPH_CAP_AUTH_EXCL avoids a cap revoke
message.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/caps.c | 21 +++++++++++++++------
 fs/ceph/dir.c  |  6 +++---
 fs/ceph/file.c |  2 +-
 3 files changed, 19 insertions(+), 10 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index a14b2c974c9e..029cab713731 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -3939,11 +3939,20 @@ int ceph_encode_inode_release(void **p, struct inode *inode,
 
 	cap = __get_cap_for_mds(ci, mds);
 	if (cap && __cap_is_valid(cap)) {
-		if (force ||
-		    ((cap->issued & drop) &&
-		     (cap->issued & unless) == 0)) {
-			if ((cap->issued & drop) &&
-			    (cap->issued & unless) == 0) {
+		unless &= cap->issued;
+		if (unless) {
+			if (unless & CEPH_CAP_AUTH_EXCL)
+				drop &= ~CEPH_CAP_AUTH_SHARED;
+			if (unless & CEPH_CAP_LINK_EXCL)
+				drop &= ~CEPH_CAP_LINK_SHARED;
+			if (unless & CEPH_CAP_XATTR_EXCL)
+				drop &= ~CEPH_CAP_XATTR_SHARED;
+			if (unless & CEPH_CAP_FILE_EXCL)
+				drop &= ~CEPH_CAP_FILE_SHARED;
+		}
+
+		if (force || (cap->issued & drop)) {
+			if (cap->issued & drop) {
 				int wanted = __ceph_caps_wanted(ci);
 				if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0)
 					wanted |= cap->mds_wanted;
@@ -3975,7 +3984,7 @@ int ceph_encode_inode_release(void **p, struct inode *inode,
 			*p += sizeof(*rel);
 			ret = 1;
 		} else {
-			dout("encode_inode_release %p cap %p %s\n",
+			dout("encode_inode_release %p cap %p %s (noop)\n",
 			     inode, cap, ceph_cap_string(cap->issued));
 		}
 	}
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 8a5266699b67..3a60d113aa4e 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -835,7 +835,7 @@ static int ceph_mknod(struct inode *dir, struct dentry *dentry,
 	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 	req->r_args.mknod.mode = cpu_to_le32(mode);
 	req->r_args.mknod.rdev = cpu_to_le32(rdev);
-	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
+	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 	if (acls.pagelist) {
 		req->r_pagelist = acls.pagelist;
@@ -887,7 +887,7 @@ static int ceph_symlink(struct inode *dir, struct dentry *dentry,
 	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 	req->r_dentry = dget(dentry);
 	req->r_num_caps = 2;
-	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
+	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 	err = ceph_mdsc_do_request(mdsc, dir, req);
 	if (!err && !req->r_reply_info.head->is_dentry)
@@ -936,7 +936,7 @@ static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 	req->r_parent = dir;
 	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 	req->r_args.mkdir.mode = cpu_to_le32(mode);
-	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
+	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 	if (acls.pagelist) {
 		req->r_pagelist = acls.pagelist;
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 5c17125f45c7..770dd3b413e4 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -396,7 +396,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 	req->r_dentry = dget(dentry);
 	req->r_num_caps = 2;
 	if (flags & O_CREAT) {
-		req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
+		req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 		req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 		if (acls.pagelist) {
 			req->r_pagelist = acls.pagelist;
-- 
cgit v1.2.3-58-ga151


From d19a0b540182a742338d88f6501e4f29a30d7541 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Thu, 23 Nov 2017 17:59:13 +0800
Subject: ceph: voluntarily drop Lx cap for link/rename requests

MDS need to xlock inode's linklock when handling link/rename requests.
Voluntarily dropping CEPH_CAP_AUTH_EXCL avoids a cap revoke message.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/dir.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 3a60d113aa4e..aa2618f12cb7 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -983,7 +983,7 @@ static int ceph_link(struct dentry *old_dentry, struct inode *dir,
 	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 	/* release LINK_SHARED on source inode (mds will lock it) */
-	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
+	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
 	err = ceph_mdsc_do_request(mdsc, dir, req);
 	if (err) {
 		d_drop(dentry);
@@ -1096,7 +1096,7 @@ static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
 	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 	/* release LINK_RDCACHE on source inode (mds will lock it) */
-	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
+	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
 	if (d_really_is_positive(new_dentry))
 		req->r_inode_drop = drop_caps_for_unlink(d_inode(new_dentry));
 	err = ceph_mdsc_do_request(mdsc, old_dir, req);
-- 
cgit v1.2.3-58-ga151


From be70489eff41a84f26b1d772b595cc043e0edeb6 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Thu, 23 Nov 2017 18:22:06 +0800
Subject: ceph: properly drop caps for setattr request

For CEPH_SETATTR_ATIME, MDS needs to xlock filelock, Fsxrw caps
are not allowed for xlocked filelock.

For CEPH_SETATTR_SIZE request that truncates file to smaller size,
MDS needs to xlock filelock, Fsxrw caps are not allowed for xlocked
filelock.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/inode.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index ab81652198c4..666ad10e2b85 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2000,8 +2000,8 @@ int __ceph_setattr(struct inode *inode, struct iattr *attr)
 			ceph_encode_timespec(&req->r_args.setattr.atime,
 					     &attr->ia_atime);
 			mask |= CEPH_SETATTR_ATIME;
-			release |= CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_RD |
-				CEPH_CAP_FILE_WR;
+			release |= CEPH_CAP_FILE_SHARED |
+				   CEPH_CAP_FILE_RD | CEPH_CAP_FILE_WR;
 		}
 	}
 	if (ia_valid & ATTR_MTIME) {
@@ -2022,8 +2022,8 @@ int __ceph_setattr(struct inode *inode, struct iattr *attr)
 			ceph_encode_timespec(&req->r_args.setattr.mtime,
 					     &attr->ia_mtime);
 			mask |= CEPH_SETATTR_MTIME;
-			release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_RD |
-				CEPH_CAP_FILE_WR;
+			release |= CEPH_CAP_FILE_SHARED |
+				   CEPH_CAP_FILE_RD | CEPH_CAP_FILE_WR;
 		}
 	}
 	if (ia_valid & ATTR_SIZE) {
@@ -2041,8 +2041,8 @@ int __ceph_setattr(struct inode *inode, struct iattr *attr)
 			req->r_args.setattr.old_size =
 				cpu_to_le64(inode->i_size);
 			mask |= CEPH_SETATTR_SIZE;
-			release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_RD |
-				CEPH_CAP_FILE_WR;
+			release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_EXCL |
+				   CEPH_CAP_FILE_RD | CEPH_CAP_FILE_WR;
 		}
 	}
 
-- 
cgit v1.2.3-58-ga151


From 87c91a965aa28809888cbae3b2de35a486ed7107 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Thu, 23 Nov 2017 18:28:16 +0800
Subject: ceph: voluntarily drop Fx cap for readdir request

MDS need to rdlock directory inode's filelock when handling readdir
request. Voluntarily dropping CEPH_CAP_AUTH_EXCL avoids a cap revoke
message.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/dir.c | 1 +
 1 file changed, 1 insertion(+)

(limited to 'fs/ceph')

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index aa2618f12cb7..9fde02cd5568 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -381,6 +381,7 @@ more:
 		if (op == CEPH_MDS_OP_READDIR) {
 			req->r_direct_hash = ceph_frag_value(frag);
 			__set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
+			req->r_inode_drop = CEPH_CAP_FILE_EXCL;
 		}
 		if (fi->last_name) {
 			req->r_path2 = kstrdup(fi->last_name, GFP_KERNEL);
-- 
cgit v1.2.3-58-ga151


From 8d8f371c83838d74bc3d0708afba631488a12201 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Fri, 24 Nov 2017 11:51:32 +0800
Subject: ceph: cleanup traceless reply handling for rename

ceph_fill_trace() already calls ceph_invalidate_dir_request() for
traceless reply. No need to duplicate the code in ceph_rename().

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/dir.c        | 9 ---------
 fs/ceph/mds_client.c | 9 ++++++---
 2 files changed, 6 insertions(+), 12 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 9fde02cd5568..64afa46b211f 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -1107,16 +1107,7 @@ static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
 		 * do_request, above).  If there is no trace, we need
 		 * to do it here.
 		 */
-
-		/* d_move screws up sibling dentries' offsets */
-		ceph_dir_clear_complete(old_dir);
-		ceph_dir_clear_complete(new_dir);
-
 		d_move(old_dentry, new_dentry);
-
-		/* ensure target dentry is invalidated, despite
-		   rehashing bug in vfs_rename_dir */
-		ceph_invalidate_dentry_lease(new_dentry);
 	}
 	ceph_mdsc_put_request(req);
 	return err;
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 1b468250e947..251dc44d84a0 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2438,11 +2438,14 @@ out:
  */
 void ceph_invalidate_dir_request(struct ceph_mds_request *req)
 {
-	struct inode *inode = req->r_parent;
+	struct inode *dir = req->r_parent;
+	struct inode *old_dir = req->r_old_dentry_dir;
 
-	dout("invalidate_dir_request %p (complete, lease(s))\n", inode);
+	dout("invalidate_dir_request %p %p (complete, lease(s))\n", dir, old_dir);
 
-	ceph_dir_clear_complete(inode);
+	ceph_dir_clear_complete(dir);
+	if (old_dir)
+		ceph_dir_clear_complete(old_dir);
 	if (req->r_dentry)
 		ceph_invalidate_dentry_lease(req->r_dentry);
 	if (req->r_old_dentry)
-- 
cgit v1.2.3-58-ga151


From 97aeb6bf988e0830fd80dca724fd89526b3f35e4 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Mon, 27 Nov 2017 10:47:46 +0800
Subject: ceph: use atomic_t for ceph_inode_info::i_shared_gen

It allows accessing i_shared_gen without holding i_ceph_lock. It is
preparation for later patch.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/caps.c  |  2 +-
 fs/ceph/dir.c   | 14 +++++++-------
 fs/ceph/inode.c |  4 ++--
 fs/ceph/super.h |  5 +++--
 4 files changed, 13 insertions(+), 12 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 029cab713731..57120e3d44de 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -498,7 +498,7 @@ static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
 	 */
 	if ((issued & CEPH_CAP_FILE_SHARED) != (had & CEPH_CAP_FILE_SHARED)) {
 		if (issued & CEPH_CAP_FILE_SHARED)
-			ci->i_shared_gen++;
+			atomic_inc(&ci->i_shared_gen);
 		if (S_ISDIR(ci->vfs_inode.i_mode)) {
 			dout(" marking %p NOT complete\n", &ci->vfs_inode);
 			__ceph_dir_clear_complete(ci);
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 64afa46b211f..d671d5876828 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -173,7 +173,7 @@ __dcache_find_get_entry(struct dentry *parent, u64 idx,
  * the MDS if/when the directory is modified).
  */
 static int __dcache_readdir(struct file *file,  struct dir_context *ctx,
-			    u32 shared_gen)
+			    int shared_gen)
 {
 	struct ceph_file_info *fi = file->private_data;
 	struct dentry *parent = file->f_path.dentry;
@@ -184,7 +184,7 @@ static int __dcache_readdir(struct file *file,  struct dir_context *ctx,
 	u64 idx = 0;
 	int err = 0;
 
-	dout("__dcache_readdir %p v%u at %llx\n", dir, shared_gen, ctx->pos);
+	dout("__dcache_readdir %p v%u at %llx\n", dir, (unsigned)shared_gen, ctx->pos);
 
 	/* search start position */
 	if (ctx->pos > 2) {
@@ -333,7 +333,7 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
 	    ceph_snap(inode) != CEPH_SNAPDIR &&
 	    __ceph_dir_is_complete_ordered(ci) &&
 	    __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
-		u32 shared_gen = ci->i_shared_gen;
+		int shared_gen = atomic_read(&ci->i_shared_gen);
 		spin_unlock(&ci->i_ceph_lock);
 		err = __dcache_readdir(file, ctx, shared_gen);
 		if (err != -EAGAIN)
@@ -751,7 +751,7 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
 			spin_unlock(&ci->i_ceph_lock);
 			dout(" dir %p complete, -ENOENT\n", dir);
 			d_add(dentry, NULL);
-			di->lease_shared_gen = ci->i_shared_gen;
+			di->lease_shared_gen = atomic_read(&ci->i_shared_gen);
 			return NULL;
 		}
 		spin_unlock(&ci->i_ceph_lock);
@@ -1191,12 +1191,12 @@ static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
 	int valid = 0;
 
 	spin_lock(&ci->i_ceph_lock);
-	if (ci->i_shared_gen == di->lease_shared_gen)
+	if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen)
 		valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
 	spin_unlock(&ci->i_ceph_lock);
 	dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n",
-	     dir, (unsigned)ci->i_shared_gen, dentry,
-	     (unsigned)di->lease_shared_gen, valid);
+	     dir, (unsigned)atomic_read(&ci->i_shared_gen),
+	     dentry, (unsigned)di->lease_shared_gen, valid);
 	return valid;
 }
 
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 666ad10e2b85..6d02528eb61f 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -494,7 +494,7 @@ struct inode *ceph_alloc_inode(struct super_block *sb)
 	ci->i_wrbuffer_ref = 0;
 	ci->i_wrbuffer_ref_head = 0;
 	atomic_set(&ci->i_filelock_ref, 0);
-	ci->i_shared_gen = 0;
+	atomic_set(&ci->i_shared_gen, 0);
 	ci->i_rdcache_gen = 0;
 	ci->i_rdcache_revoking = 0;
 
@@ -1041,7 +1041,7 @@ static void update_dentry_lease(struct dentry *dentry,
 	if (ceph_snap(dir) != CEPH_NOSNAP)
 		goto out_unlock;
 
-	di->lease_shared_gen = ceph_inode(dir)->i_shared_gen;
+	di->lease_shared_gen = atomic_read(&ceph_inode(dir)->i_shared_gen);
 
 	if (duration == 0)
 		goto out_unlock;
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 2beeec07fa76..75701c199b2b 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -256,7 +256,8 @@ struct ceph_inode_xattr {
  */
 struct ceph_dentry_info {
 	struct ceph_mds_session *lease_session;
-	u32 lease_gen, lease_shared_gen;
+	int lease_shared_gen;
+	u32 lease_gen;
 	u32 lease_seq;
 	unsigned long lease_renew_after, lease_renew_from;
 	struct list_head lru;
@@ -353,7 +354,7 @@ struct ceph_inode_info {
 	int i_rd_ref, i_rdcache_ref, i_wr_ref, i_wb_ref;
 	int i_wrbuffer_ref, i_wrbuffer_ref_head;
 	atomic_t i_filelock_ref;
-	u32 i_shared_gen;       /* increment each time we get FILE_SHARED */
+	atomic_t i_shared_gen;       /* increment each time we get FILE_SHARED */
 	u32 i_rdcache_gen;      /* incremented each time we get FILE_CACHE. */
 	u32 i_rdcache_revoking; /* RDCACHE gen to async invalidate, if any */
 
-- 
cgit v1.2.3-58-ga151


From 5495c2d04f85da09512f5f346ed24dc0261d905d Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Mon, 27 Nov 2017 11:23:48 +0800
Subject: ceph: avoid dereferencing invalid pointer during cached readdir

Readdir cache keeps array of dentry pointers in page cache. If any
dentry in readdir cache gets pruned, ceph_d_prune() disables readdir
cache for later readdir syscall. The problem is that ceph_d_prune()
ignores unhashed dentry. Ideally MDS should have already revoked
CEPH_CAP_FILE_SHARED (which also disables readdir cache) when dentry
gets unhashed. But if it is somehow MDS does not properly revoke
CEPH_CAP_FILE_SHARED and the unhashed dentry gets pruned later,
ceph_d_prune() will not disable readdir cache, later readdir may
reference invalid dentry pointer.

The fix is make ceph_d_prune() do extra check for unhashed dentry.
Disable readdir cache if the unhashed dentry is still referenced
by readdir cache.

Another fix in this patch is handle d_splice_alias(). If a dentry
gets spliced into new parent dentry, treat it as if it was pruned
(call ceph_d_prune() for it).

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/dir.c   | 45 ++++++++++++++++++++++++++++++++-------------
 fs/ceph/inode.c | 40 ++++++++++++++++++++++++++++++++++------
 2 files changed, 66 insertions(+), 19 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index d671d5876828..0c4346806e17 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -231,11 +231,17 @@ static int __dcache_readdir(struct file *file,  struct dir_context *ctx,
 			goto out;
 		}
 
-		di = ceph_dentry(dentry);
 		spin_lock(&dentry->d_lock);
-		if (di->lease_shared_gen == shared_gen &&
-		    d_really_is_positive(dentry) &&
-		    fpos_cmp(ctx->pos, di->offset) <= 0) {
+		di = ceph_dentry(dentry);
+		if (d_unhashed(dentry) ||
+		    d_really_is_negative(dentry) ||
+		    di->lease_shared_gen != shared_gen) {
+			spin_unlock(&dentry->d_lock);
+			dput(dentry);
+			err = -EAGAIN;
+			goto out;
+		}
+		if (fpos_cmp(ctx->pos, di->offset) <= 0) {
 			emit_dentry = true;
 		}
 		spin_unlock(&dentry->d_lock);
@@ -1324,24 +1330,37 @@ static void ceph_d_release(struct dentry *dentry)
  */
 static void ceph_d_prune(struct dentry *dentry)
 {
-	dout("ceph_d_prune %p\n", dentry);
+	struct ceph_inode_info *dir_ci;
+	struct ceph_dentry_info *di;
+
+	dout("ceph_d_prune %pd %p\n", dentry, dentry);
 
 	/* do we have a valid parent? */
 	if (IS_ROOT(dentry))
 		return;
 
-	/* if we are not hashed, we don't affect dir's completeness */
-	if (d_unhashed(dentry))
+	/* we hold d_lock, so d_parent is stable */
+	dir_ci = ceph_inode(d_inode(dentry->d_parent));
+	if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
 		return;
 
-	if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_SNAPDIR)
+	/* who calls d_delete() should also disable dcache readdir */
+	if (d_really_is_negative(dentry))
 		return;
 
-	/*
-	 * we hold d_lock, so d_parent is stable, and d_fsdata is never
-	 * cleared until d_release
-	 */
-	ceph_dir_clear_complete(d_inode(dentry->d_parent));
+	/* d_fsdata does not get cleared until d_release */
+	if (!d_unhashed(dentry)) {
+		__ceph_dir_clear_complete(dir_ci);
+		return;
+	}
+
+	/* Disable dcache readdir just in case that someone called d_drop()
+	 * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
+	 * properly (dcache readdir is still enabled) */
+	di = ceph_dentry(dentry);
+	if (di->offset > 0 &&
+	    di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))
+		__ceph_dir_clear_ordered(dir_ci);
 }
 
 /*
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 6d02528eb61f..c6ec5aa46100 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1080,6 +1080,27 @@ static struct dentry *splice_dentry(struct dentry *dn, struct inode *in)
 
 	BUG_ON(d_inode(dn));
 
+	if (S_ISDIR(in->i_mode)) {
+		/* If inode is directory, d_splice_alias() below will remove
+		 * 'realdn' from its origin parent. We need to ensure that
+		 * origin parent's readdir cache will not reference 'realdn'
+		 */
+		realdn = d_find_any_alias(in);
+		if (realdn) {
+			struct ceph_dentry_info *di = ceph_dentry(realdn);
+			spin_lock(&realdn->d_lock);
+
+			realdn->d_op->d_prune(realdn);
+
+			di->time = jiffies;
+			di->lease_shared_gen = 0;
+			di->offset = 0;
+
+			spin_unlock(&realdn->d_lock);
+			dput(realdn);
+		}
+	}
+
 	/* dn must be unhashed */
 	if (!d_unhashed(dn))
 		d_drop(dn);
@@ -1295,8 +1316,8 @@ retry_lookup:
 		if (!rinfo->head->is_target) {
 			dout("fill_trace null dentry\n");
 			if (d_really_is_positive(dn)) {
-				ceph_dir_clear_ordered(dir);
 				dout("d_delete %p\n", dn);
+				ceph_dir_clear_ordered(dir);
 				d_delete(dn);
 			} else if (have_lease) {
 				if (d_unhashed(dn))
@@ -1323,7 +1344,6 @@ retry_lookup:
 			dout(" %p links to %p %llx.%llx, not %llx.%llx\n",
 			     dn, d_inode(dn), ceph_vinop(d_inode(dn)),
 			     ceph_vinop(in));
-			ceph_dir_clear_ordered(dir);
 			d_invalidate(dn);
 			have_lease = false;
 		}
@@ -1573,9 +1593,19 @@ retry_lookup:
 		} else if (d_really_is_positive(dn) &&
 			   (ceph_ino(d_inode(dn)) != tvino.ino ||
 			    ceph_snap(d_inode(dn)) != tvino.snap)) {
+			struct ceph_dentry_info *di = ceph_dentry(dn);
 			dout(" dn %p points to wrong inode %p\n",
 			     dn, d_inode(dn));
-			__ceph_dir_clear_ordered(ci);
+
+			spin_lock(&dn->d_lock);
+			if (di->offset > 0 &&
+			    di->lease_shared_gen ==
+			    atomic_read(&ci->i_shared_gen)) {
+				__ceph_dir_clear_ordered(ci);
+				di->offset = 0;
+			}
+			spin_unlock(&dn->d_lock);
+
 			d_delete(dn);
 			dput(dn);
 			goto retry_lookup;
@@ -1600,9 +1630,7 @@ retry_lookup:
 				 &req->r_caps_reservation);
 		if (ret < 0) {
 			pr_err("fill_inode badness on %p\n", in);
-			if (d_really_is_positive(dn))
-				__ceph_dir_clear_ordered(ci);
-			else
+			if (d_really_is_negative(dn))
 				iput(in);
 			d_drop(dn);
 			err = ret;
-- 
cgit v1.2.3-58-ga151


From 5d988308283ecf062fa88f20ae05c52cce0bcdca Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Fri, 15 Dec 2017 11:15:36 +0800
Subject: ceph: track read contexts in ceph_file_info

Previously ceph_read_iter() uses current->journal to pass context info
to ceph_readpages(), so that ceph_readpages() can distinguish read(2)
from readahead(2)/fadvise(2)/madvise(2). The problem is that page fault
can happen when copying data to userspace memory. Page fault may call
other filesystem's page_mkwrite() if the userspace memory is mapped to a
file. The later filesystem may also want to use current->journal.

The fix is define a on-stack data structure in ceph_read_iter(), add it
to context list in ceph_file_info. ceph_readpages() searches the list,
find if there is a context belongs to current thread.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/addr.c  | 19 ++++++++++++-------
 fs/ceph/file.c  | 10 ++++++++--
 fs/ceph/super.h | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 66 insertions(+), 9 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index dbf07051aacd..78a1208b878e 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -299,7 +299,8 @@ unlock:
  * start an async read(ahead) operation.  return nr_pages we submitted
  * a read for on success, or negative error code.
  */
-static int start_read(struct inode *inode, struct list_head *page_list, int max)
+static int start_read(struct inode *inode, struct ceph_rw_context *rw_ctx,
+		      struct list_head *page_list, int max)
 {
 	struct ceph_osd_client *osdc =
 		&ceph_inode_to_client(inode)->client->osdc;
@@ -316,7 +317,7 @@ static int start_read(struct inode *inode, struct list_head *page_list, int max)
 	int got = 0;
 	int ret = 0;
 
-	if (!current->journal_info) {
+	if (!rw_ctx) {
 		/* caller of readpages does not hold buffer and read caps
 		 * (fadvise, madvise and readahead cases) */
 		int want = CEPH_CAP_FILE_CACHE;
@@ -437,6 +438,8 @@ static int ceph_readpages(struct file *file, struct address_space *mapping,
 {
 	struct inode *inode = file_inode(file);
 	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+	struct ceph_file_info *ci = file->private_data;
+	struct ceph_rw_context *rw_ctx;
 	int rc = 0;
 	int max = 0;
 
@@ -449,11 +452,12 @@ static int ceph_readpages(struct file *file, struct address_space *mapping,
 	if (rc == 0)
 		goto out;
 
+	rw_ctx = ceph_find_rw_context(ci);
 	max = fsc->mount_options->rsize >> PAGE_SHIFT;
-	dout("readpages %p file %p nr_pages %d max %d\n",
-	     inode, file, nr_pages, max);
+	dout("readpages %p file %p ctx %p nr_pages %d max %d\n",
+	     inode, file, rw_ctx, nr_pages, max);
 	while (!list_empty(page_list)) {
-		rc = start_read(inode, page_list, max);
+		rc = start_read(inode, rw_ctx, page_list, max);
 		if (rc < 0)
 			goto out;
 	}
@@ -1450,9 +1454,10 @@ static int ceph_filemap_fault(struct vm_fault *vmf)
 
 	if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) ||
 	    ci->i_inline_version == CEPH_INLINE_NONE) {
-		current->journal_info = vma->vm_file;
+		CEPH_DEFINE_RW_CONTEXT(rw_ctx, got);
+		ceph_add_rw_context(fi, &rw_ctx);
 		ret = filemap_fault(vmf);
-		current->journal_info = NULL;
+		ceph_del_rw_context(fi, &rw_ctx);
 	} else
 		ret = -EAGAIN;
 
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 770dd3b413e4..6639926eed4e 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -181,6 +181,10 @@ static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
 			return -ENOMEM;
 		}
 		cf->fmode = fmode;
+
+		spin_lock_init(&cf->rw_contexts_lock);
+		INIT_LIST_HEAD(&cf->rw_contexts);
+
 		cf->next_offset = 2;
 		cf->readdir_cache_idx = -1;
 		file->private_data = cf;
@@ -464,6 +468,7 @@ int ceph_release(struct inode *inode, struct file *file)
 		ceph_mdsc_put_request(cf->last_readdir);
 	kfree(cf->last_name);
 	kfree(cf->dir_info);
+	WARN_ON(!list_empty(&cf->rw_contexts));
 	kmem_cache_free(ceph_file_cachep, cf);
 
 	/* wake up anyone waiting for caps on this inode */
@@ -1199,12 +1204,13 @@ again:
 			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));
-		current->journal_info = filp;
+		ceph_add_rw_context(fi, &rw_ctx);
 		ret = generic_file_read_iter(iocb, to);
-		current->journal_info = NULL;
+		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);
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 75701c199b2b..601100da738f 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -669,6 +669,9 @@ struct ceph_file_info {
 	short fmode;     /* initialized on open */
 	short flags;     /* CEPH_F_* */
 
+	spinlock_t rw_contexts_lock;
+	struct list_head rw_contexts;
+
 	/* readdir: position within the dir */
 	u32 frag;
 	struct ceph_mds_request *last_readdir;
@@ -685,6 +688,49 @@ struct ceph_file_info {
 	int dir_info_len;
 };
 
+struct ceph_rw_context {
+	struct list_head list;
+	struct task_struct *thread;
+	int caps;
+};
+
+#define CEPH_DEFINE_RW_CONTEXT(_name, _caps)	\
+	struct ceph_rw_context _name = {	\
+		.thread = current,		\
+		.caps = _caps,			\
+	}
+
+static inline void ceph_add_rw_context(struct ceph_file_info *cf,
+				       struct ceph_rw_context *ctx)
+{
+	spin_lock(&cf->rw_contexts_lock);
+	list_add(&ctx->list, &cf->rw_contexts);
+	spin_unlock(&cf->rw_contexts_lock);
+}
+
+static inline void ceph_del_rw_context(struct ceph_file_info *cf,
+				       struct ceph_rw_context *ctx)
+{
+	spin_lock(&cf->rw_contexts_lock);
+	list_del(&ctx->list);
+	spin_unlock(&cf->rw_contexts_lock);
+}
+
+static inline struct ceph_rw_context*
+ceph_find_rw_context(struct ceph_file_info *cf)
+{
+	struct ceph_rw_context *ctx, *found = NULL;
+	spin_lock(&cf->rw_contexts_lock);
+	list_for_each_entry(ctx, &cf->rw_contexts, list) {
+		if (ctx->thread == current) {
+			found = ctx;
+			break;
+		}
+	}
+	spin_unlock(&cf->rw_contexts_lock);
+	return found;
+}
+
 struct ceph_readdir_cache_control {
 	struct page  *page;
 	struct dentry **dentries;
-- 
cgit v1.2.3-58-ga151


From 314c4737a45dd4447eac6d313e3715b25785f58b Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Fri, 15 Dec 2017 16:57:40 +0800
Subject: ceph: fix un-balanced fsc->writeback_count update

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/addr.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 78a1208b878e..b4336b42ce3b 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -578,7 +578,6 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 	struct ceph_fs_client *fsc;
 	struct ceph_snap_context *snapc, *oldest;
 	loff_t page_off = page_offset(page);
-	long writeback_stat;
 	int err, len = PAGE_SIZE;
 	struct ceph_writeback_ctl ceph_wbc;
 
@@ -619,8 +618,7 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 	dout("writepage %p page %p index %lu on %llu~%u snapc %p seq %lld\n",
 	     inode, page, page->index, page_off, len, snapc, snapc->seq);
 
-	writeback_stat = atomic_long_inc_return(&fsc->writeback_count);
-	if (writeback_stat >
+	if (atomic_long_inc_return(&fsc->writeback_count) >
 	    CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
 		set_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC);
 
@@ -655,6 +653,11 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 	end_page_writeback(page);
 	ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
 	ceph_put_snap_context(snapc);  /* page's reference */
+
+	if (atomic_long_dec_return(&fsc->writeback_count) <
+	    CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
+		clear_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC);
+
 	return err;
 }
 
-- 
cgit v1.2.3-58-ga151


From 7d9c9193b5d0b1b806f453a3baa9bfe7e6fac52d Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Tue, 19 Dec 2017 18:00:54 +0800
Subject: ceph: fix incorrect snaprealm when adding caps

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/caps.c | 14 +++++++++++++-
 fs/ceph/snap.c |  8 ++++++--
 2 files changed, 19 insertions(+), 3 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 57120e3d44de..7e09fa8ab0ed 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -577,18 +577,30 @@ void ceph_add_cap(struct inode *inode,
 		}
 	}
 
-	if (!ci->i_snap_realm) {
+	if (!ci->i_snap_realm ||
+	    ((flags & CEPH_CAP_FLAG_AUTH) &&
+	     realmino != (u64)-1 && ci->i_snap_realm->ino != realmino)) {
 		/*
 		 * add this inode to the appropriate snap realm
 		 */
 		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
 							       realmino);
 		if (realm) {
+			struct ceph_snap_realm *oldrealm = ci->i_snap_realm;
+			if (oldrealm) {
+				spin_lock(&oldrealm->inodes_with_caps_lock);
+				list_del_init(&ci->i_snap_realm_item);
+				spin_unlock(&oldrealm->inodes_with_caps_lock);
+			}
+
 			spin_lock(&realm->inodes_with_caps_lock);
 			ci->i_snap_realm = realm;
 			list_add(&ci->i_snap_realm_item,
 				 &realm->inodes_with_caps);
 			spin_unlock(&realm->inodes_with_caps_lock);
+
+			if (oldrealm)
+				ceph_put_snap_realm(mdsc, oldrealm);
 		} else {
 			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
 			       realmino);
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index 8a2ca41e4b97..07cf95e6413d 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -922,13 +922,17 @@ void ceph_handle_snap(struct ceph_mds_client *mdsc,
 			/*
 			 * Move the inode to the new realm
 			 */
-			spin_lock(&realm->inodes_with_caps_lock);
+			oldrealm = ci->i_snap_realm;
+			spin_lock(&oldrealm->inodes_with_caps_lock);
 			list_del_init(&ci->i_snap_realm_item);
+			spin_unlock(&oldrealm->inodes_with_caps_lock);
+
+			spin_lock(&realm->inodes_with_caps_lock);
 			list_add(&ci->i_snap_realm_item,
 				 &realm->inodes_with_caps);
-			oldrealm = ci->i_snap_realm;
 			ci->i_snap_realm = realm;
 			spin_unlock(&realm->inodes_with_caps_lock);
+
 			spin_unlock(&ci->i_ceph_lock);
 
 			ceph_get_snap_realm(mdsc, realm);
-- 
cgit v1.2.3-58-ga151


From d84b37f9fa9b23a46af28d2e9430c87718b6b044 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Wed, 3 Jan 2018 11:16:27 +0800
Subject: ceph: limit rate of cap import/export error messages

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/caps.c | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 7e09fa8ab0ed..f28efaecbb50 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -3438,7 +3438,14 @@ retry:
 	 */
 
 	issued = cap->issued;
-	WARN_ON(issued != cap->implemented);
+	if (issued != cap->implemented)
+		pr_err_ratelimited("handle_cap_export: issued != implemented: "
+				"ino (%llx.%llx) mds%d seq %d mseq %d "
+				"issued %s implemented %s\n",
+				ceph_vinop(inode), mds, cap->seq, cap->mseq,
+				ceph_cap_string(issued),
+				ceph_cap_string(cap->implemented));
+
 
 	tcap = __get_cap_for_mds(ci, target);
 	if (tcap) {
@@ -3584,12 +3591,13 @@ retry:
 		if ((ph->flags & CEPH_CAP_FLAG_AUTH) &&
 		    (ocap->seq != le32_to_cpu(ph->seq) ||
 		     ocap->mseq != le32_to_cpu(ph->mseq))) {
-			pr_err("handle_cap_import: mismatched seq/mseq: "
-			       "ino (%llx.%llx) mds%d seq %d mseq %d "
-			       "importer mds%d has peer seq %d mseq %d\n",
-			       ceph_vinop(inode), peer, ocap->seq,
-			       ocap->mseq, mds, le32_to_cpu(ph->seq),
-			       le32_to_cpu(ph->mseq));
+			pr_err_ratelimited("handle_cap_import: "
+					"mismatched seq/mseq: ino (%llx.%llx) "
+					"mds%d seq %d mseq %d importer mds%d "
+					"has peer seq %d mseq %d\n",
+					ceph_vinop(inode), peer, ocap->seq,
+					ocap->mseq, mds, le32_to_cpu(ph->seq),
+					le32_to_cpu(ph->mseq));
 		}
 		__ceph_remove_cap(ocap, (ph->flags & CEPH_CAP_FLAG_RELEASE));
 	}
-- 
cgit v1.2.3-58-ga151


From ee612d954fe96612afaa966d8a67b736ba0c571e Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Mon, 8 Jan 2018 14:36:25 +0800
Subject: ceph: delete unreachable code in ceph_check_caps()

"revoking & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)" has already
been tested before calling try_nonblocking_invalidate()

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/caps.c | 15 +++------------
 1 file changed, 3 insertions(+), 12 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index f28efaecbb50..36f8a4bdf8c5 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -1793,18 +1793,9 @@ retry_locked:
 	    !tried_invalidate) {
 		dout("check_caps trying to invalidate on %p\n", inode);
 		if (try_nonblocking_invalidate(inode) < 0) {
-			if (revoking & (CEPH_CAP_FILE_CACHE|
-					CEPH_CAP_FILE_LAZYIO)) {
-				dout("check_caps queuing invalidate\n");
-				queue_invalidate = true;
-				ci->i_rdcache_revoking = ci->i_rdcache_gen;
-			} else {
-				dout("check_caps failed to invalidate pages\n");
-				/* we failed to invalidate pages.  check these
-				   caps again later. */
-				force_requeue = true;
-				__cap_set_timeouts(mdsc, ci);
-			}
+			dout("check_caps queuing invalidate\n");
+			queue_invalidate = true;
+			ci->i_rdcache_revoking = ci->i_rdcache_gen;
 		}
 		tried_invalidate = true;
 		goto retry_locked;
-- 
cgit v1.2.3-58-ga151


From 0f439c746c8cb370ce3ae1668182b18a5cb12b14 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Mon, 8 Jan 2018 14:44:10 +0800
Subject: ceph: fix race of queuing delayed caps

When called with CHECK_CAPS_AUTHONLY flag, ceph_check_caps() only
processes auth caps. In that case, it's unsafe to remove inode
from mdsc->cap_delay_list, because there can be delayed non-auth
caps.

Besides, ceph_check_caps() may lock/unlock i_ceph_lock several
times, when multiple threads call ceph_check_caps() at the same
time. It's possible that one thread calls __cap_delay_requeue(),
another thread calls __cap_delay_cancel(). __cap_delay_cancel()
should be called at very beginning of ceph_check_caps(), so that
it does not race with __cap_delay_requeue().

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/caps.c | 33 ++++++++++++++++-----------------
 1 file changed, 16 insertions(+), 17 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 36f8a4bdf8c5..1726ddcf5e34 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -902,6 +902,11 @@ int __ceph_caps_mds_wanted(struct ceph_inode_info *ci, bool check)
 /*
  * called under i_ceph_lock
  */
+static int __ceph_is_single_caps(struct ceph_inode_info *ci)
+{
+	return rb_first(&ci->i_caps) == rb_last(&ci->i_caps);
+}
+
 static int __ceph_is_any_caps(struct ceph_inode_info *ci)
 {
 	return !RB_EMPTY_ROOT(&ci->i_caps);
@@ -1715,21 +1720,24 @@ void ceph_check_caps(struct ceph_inode_info *ci, int flags,
 	int mds = -1;   /* keep track of how far we've gone through i_caps list
 			   to avoid an infinite loop on retry */
 	struct rb_node *p;
-	int delayed = 0, sent = 0, num;
-	bool is_delayed = flags & CHECK_CAPS_NODELAY;
+	int delayed = 0, sent = 0;
+	bool no_delay = flags & CHECK_CAPS_NODELAY;
 	bool queue_invalidate = false;
-	bool force_requeue = false;
 	bool tried_invalidate = false;
 
 	/* if we are unmounting, flush any unused caps immediately. */
 	if (mdsc->stopping)
-		is_delayed = true;
+		no_delay = true;
 
 	spin_lock(&ci->i_ceph_lock);
 
 	if (ci->i_ceph_flags & CEPH_I_FLUSH)
 		flags |= CHECK_CAPS_FLUSH;
 
+	if (!(flags & CHECK_CAPS_AUTHONLY) ||
+	    (ci->i_auth_cap && __ceph_is_single_caps(ci)))
+		__cap_delay_cancel(mdsc, ci);
+
 	goto retry_locked;
 retry:
 	spin_lock(&ci->i_ceph_lock);
@@ -1784,7 +1792,7 @@ retry_locked:
 	 * have cached pages, but don't want them, then try to invalidate.
 	 * If we fail, it's because pages are locked.... try again later.
 	 */
-	if ((!is_delayed || mdsc->stopping) &&
+	if ((!no_delay || mdsc->stopping) &&
 	    !S_ISDIR(inode->i_mode) &&		/* ignore readdir cache */
 	    !(ci->i_wb_ref || ci->i_wrbuffer_ref) &&   /* no dirty pages... */
 	    inode->i_data.nrpages &&		/* have cached pages */
@@ -1801,10 +1809,8 @@ retry_locked:
 		goto retry_locked;
 	}
 
-	num = 0;
 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 		cap = rb_entry(p, struct ceph_cap, ci_node);
-		num++;
 
 		/* avoid looping forever */
 		if (mds >= cap->mds ||
@@ -1867,7 +1873,7 @@ retry_locked:
 		    cap->mds_wanted == want)
 			continue;     /* nope, all good */
 
-		if (is_delayed)
+		if (no_delay)
 			goto ack;
 
 		/* delay? */
@@ -1958,15 +1964,8 @@ ack:
 		goto retry; /* retake i_ceph_lock and restart our cap scan. */
 	}
 
-	/*
-	 * Reschedule delayed caps release if we delayed anything,
-	 * otherwise cancel.
-	 */
-	if (delayed && is_delayed)
-		force_requeue = true;   /* __send_cap delayed release; requeue */
-	if (!delayed && !is_delayed)
-		__cap_delay_cancel(mdsc, ci);
-	else if (!is_delayed || force_requeue)
+	/* Reschedule delayed caps release if we delayed anything */
+	if (delayed)
 		__cap_delay_requeue(mdsc, ci);
 
 	spin_unlock(&ci->i_ceph_lock);
-- 
cgit v1.2.3-58-ga151


From e30ee58121e34831b9665934d70dbc72ab0fe2fb Mon Sep 17 00:00:00 2001
From: Zhi Zhang <zhang.david2011@gmail.com>
Date: Wed, 24 Jan 2018 21:24:33 +0800
Subject: ceph: try to allocate enough memory for reserved caps

ceph_reserve_caps() may not reserve enough caps under high memory
pressure, but it saved the needed caps number that expected to
be reserved. When getting caps, crash would happen due to number
mismatch.

Now we will try to trim more caps when failing to allocate memory
for caps need to be reserved, then try again. If still failing to
allocate memory, return -ENOMEM.

Signed-off-by: Zhi Zhang <zhang.david2011@gmail.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/caps.c       | 61 +++++++++++++++++++++++++++++++++++++++++++++-------
 fs/ceph/mds_client.c | 24 +++++++++++++++------
 fs/ceph/mds_client.h |  3 +++
 fs/ceph/super.h      |  2 +-
 4 files changed, 74 insertions(+), 16 deletions(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 1726ddcf5e34..8e66fb0e743d 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -154,13 +154,19 @@ void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta)
 	spin_unlock(&mdsc->caps_list_lock);
 }
 
-void ceph_reserve_caps(struct ceph_mds_client *mdsc,
+/*
+ * Called under mdsc->mutex.
+ */
+int ceph_reserve_caps(struct ceph_mds_client *mdsc,
 		      struct ceph_cap_reservation *ctx, int need)
 {
-	int i;
+	int i, j;
 	struct ceph_cap *cap;
 	int have;
 	int alloc = 0;
+	int max_caps;
+	bool trimmed = false;
+	struct ceph_mds_session *s;
 	LIST_HEAD(newcaps);
 
 	dout("reserve caps ctx=%p need=%d\n", ctx, need);
@@ -179,16 +185,37 @@ void ceph_reserve_caps(struct ceph_mds_client *mdsc,
 	spin_unlock(&mdsc->caps_list_lock);
 
 	for (i = have; i < need; i++) {
+retry:
 		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
-		if (!cap)
-			break;
+		if (!cap) {
+			if (!trimmed) {
+				for (j = 0; j < mdsc->max_sessions; j++) {
+					s = __ceph_lookup_mds_session(mdsc, j);
+					if (!s)
+						continue;
+					mutex_unlock(&mdsc->mutex);
+
+					mutex_lock(&s->s_mutex);
+					max_caps = s->s_nr_caps - (need - i);
+					ceph_trim_caps(mdsc, s, max_caps);
+					mutex_unlock(&s->s_mutex);
+
+					ceph_put_mds_session(s);
+					mutex_lock(&mdsc->mutex);
+				}
+				trimmed = true;
+				goto retry;
+			} else {
+				pr_warn("reserve caps ctx=%p ENOMEM "
+					"need=%d got=%d\n",
+					ctx, need, have + alloc);
+				goto out_nomem;
+			}
+		}
 		list_add(&cap->caps_item, &newcaps);
 		alloc++;
 	}
-	/* we didn't manage to reserve as much as we needed */
-	if (have + alloc != need)
-		pr_warn("reserve caps ctx=%p ENOMEM need=%d got=%d\n",
-			ctx, need, have + alloc);
+	BUG_ON(have + alloc != need);
 
 	spin_lock(&mdsc->caps_list_lock);
 	mdsc->caps_total_count += alloc;
@@ -204,6 +231,24 @@ void ceph_reserve_caps(struct ceph_mds_client *mdsc,
 	dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n",
 	     ctx, mdsc->caps_total_count, mdsc->caps_use_count,
 	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
+	return 0;
+
+out_nomem:
+	while (!list_empty(&newcaps)) {
+		cap = list_first_entry(&newcaps,
+				struct ceph_cap, caps_item);
+		list_del(&cap->caps_item);
+		kmem_cache_free(ceph_cap_cachep, cap);
+	}
+
+	spin_lock(&mdsc->caps_list_lock);
+	mdsc->caps_avail_count += have;
+	mdsc->caps_reserve_count -= have;
+	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
+					 mdsc->caps_reserve_count +
+					 mdsc->caps_avail_count);
+	spin_unlock(&mdsc->caps_list_lock);
+	return -ENOMEM;
 }
 
 int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 251dc44d84a0..2e8f90f96540 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -604,10 +604,20 @@ static void __register_request(struct ceph_mds_client *mdsc,
 			       struct ceph_mds_request *req,
 			       struct inode *dir)
 {
+	int ret = 0;
+
 	req->r_tid = ++mdsc->last_tid;
-	if (req->r_num_caps)
-		ceph_reserve_caps(mdsc, &req->r_caps_reservation,
-				  req->r_num_caps);
+	if (req->r_num_caps) {
+		ret = ceph_reserve_caps(mdsc, &req->r_caps_reservation,
+					req->r_num_caps);
+		if (ret < 0) {
+			pr_err("__register_request %p "
+			       "failed to reserve caps: %d\n", req, ret);
+			/* set req->r_err to fail early from __do_request */
+			req->r_err = ret;
+			return;
+		}
+	}
 	dout("__register_request %p tid %lld\n", req, req->r_tid);
 	ceph_mdsc_get_request(req);
 	insert_request(&mdsc->request_tree, req);
@@ -1545,9 +1555,9 @@ out:
 /*
  * Trim session cap count down to some max number.
  */
-static int trim_caps(struct ceph_mds_client *mdsc,
-		     struct ceph_mds_session *session,
-		     int max_caps)
+int ceph_trim_caps(struct ceph_mds_client *mdsc,
+		   struct ceph_mds_session *session,
+		   int max_caps)
 {
 	int trim_caps = session->s_nr_caps - max_caps;
 
@@ -2776,7 +2786,7 @@ static void handle_session(struct ceph_mds_session *session,
 		break;
 
 	case CEPH_SESSION_RECALL_STATE:
-		trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
+		ceph_trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
 		break;
 
 	case CEPH_SESSION_FLUSHMSG:
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 837ac4b087a0..71e3b783ee6f 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -444,4 +444,7 @@ ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
 					  struct ceph_mds_session *session);
 
+extern int ceph_trim_caps(struct ceph_mds_client *mdsc,
+			  struct ceph_mds_session *session,
+			  int max_caps);
 #endif
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 601100da738f..21b2e5b004eb 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -649,7 +649,7 @@ extern int __ceph_caps_mds_wanted(struct ceph_inode_info *ci, bool check);
 extern void ceph_caps_init(struct ceph_mds_client *mdsc);
 extern void ceph_caps_finalize(struct ceph_mds_client *mdsc);
 extern void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta);
-extern void ceph_reserve_caps(struct ceph_mds_client *mdsc,
+extern int ceph_reserve_caps(struct ceph_mds_client *mdsc,
 			     struct ceph_cap_reservation *ctx, int need);
 extern int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
 			       struct ceph_cap_reservation *ctx);
-- 
cgit v1.2.3-58-ga151


From 16515a6d54183349b858b9c05e483afc55fa7948 Mon Sep 17 00:00:00 2001
From: Chengguang Xu <cgxu519@icloud.com>
Date: Tue, 30 Jan 2018 10:02:30 +0800
Subject: ceph: improving efficiency of syncfs

write_inode() could be called variety of reasons, in the case of syncfs(2)
there is no need to wait for flush getting completed in write_inode(),
->sync_fs is for guaranteeing flush completion for all inodes at that point.

Signed-off-by: Chengguang Xu <cgxu519@icloud.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 fs/ceph/caps.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'fs/ceph')

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 8e66fb0e743d..6582c4507e6c 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -2207,7 +2207,7 @@ int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
 	u64 flush_tid;
 	int err = 0;
 	int dirty;
-	int wait = wbc->sync_mode == WB_SYNC_ALL;
+	int wait = (wbc->sync_mode == WB_SYNC_ALL && !wbc->for_sync);
 
 	dout("write_inode %p wait=%d\n", inode, wait);
 	if (wait) {
-- 
cgit v1.2.3-58-ga151