Merge tag 'v3.13-rc6' into for-3.14/core

Needed to bring blk-mq uptodate, since changes have been going in
since for-3.14/core was established.

Fixup merge issues related to the immutable biovec changes.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

Conflicts:
	block/blk-flush.c
	fs/btrfs/check-integrity.c
	fs/btrfs/extent_io.c
	fs/btrfs/scrub.c
	fs/logfs/dev_bdev.c

31 files changed, 375 insertions, 240 deletions

diff --git a/kernel/.gitignore b/kernel/.gitignore
index b3097bde4e9c..790d83c7d160 100644
--- a/kernel/.gitignore
+++ b/kernel/.gitignore
@@ -5,3 +5,4 @@ config_data.h
 config_data.gz
 timeconst.h
 hz.bc
+x509_certificate_list
diff --git a/kernel/Makefile b/kernel/Makefile
index bbaf7d59c1bb..bc010ee272b6 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -137,9 +137,10 @@ $(obj)/timeconst.h: $(obj)/hz.bc $(src)/timeconst.bc FORCE
 ###############################################################################
 ifeq ($(CONFIG_SYSTEM_TRUSTED_KEYRING),y)
 X509_CERTIFICATES-y := $(wildcard *.x509) $(wildcard $(srctree)/*.x509)
-X509_CERTIFICATES-$(CONFIG_MODULE_SIG) += signing_key.x509
-X509_CERTIFICATES := $(sort $(foreach CERT,$(X509_CERTIFICATES-y), \
+X509_CERTIFICATES-$(CONFIG_MODULE_SIG) += $(objtree)/signing_key.x509
+X509_CERTIFICATES-raw := $(sort $(foreach CERT,$(X509_CERTIFICATES-y), \
                                 $(or $(realpath $(CERT)),$(CERT))))
+X509_CERTIFICATES := $(subst $(realpath $(objtree))/,,$(X509_CERTIFICATES-raw))
 
 ifeq ($(X509_CERTIFICATES),)
 $(warning *** No X.509 certificates found ***)
@@ -164,9 +165,9 @@ $(obj)/x509_certificate_list: $(X509_CERTIFICATES) $(obj)/.x509.list
 targets += $(obj)/.x509.list
 $(obj)/.x509.list:
         @echo $(X509_CERTIFICATES) >$@
+endif
 
 clean-files := x509_certificate_list .x509.list
-endif
 
 ifeq ($(CONFIG_MODULE_SIG),y)
 ###############################################################################
diff --git a/kernel/bounds.c b/kernel/bounds.c
index 5253204afdca..9fd4246b04b8 100644
--- a/kernel/bounds.c
+++ b/kernel/bounds.c
@@ -22,6 +22,6 @@ void foo(void)
 #ifdef CONFIG_SMP
         DEFINE(NR_CPUS_BITS, ilog2(CONFIG_NR_CPUS));
 #endif
-        DEFINE(BLOATED_SPINLOCKS, sizeof(spinlock_t) > sizeof(int));
+        DEFINE(SPINLOCK_SIZE, sizeof(spinlock_t));
         /* End of constants */
 }
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 4c62513fe19f..bc1dcabe9217 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -90,6 +90,14 @@ static DEFINE_MUTEX(cgroup_mutex);
 static DEFINE_MUTEX(cgroup_root_mutex);
 
 /*
+ * cgroup destruction makes heavy use of work items and there can be a lot
+ * of concurrent destructions.  Use a separate workqueue so that cgroup
+ * destruction work items don't end up filling up max_active of system_wq
+ * which may lead to deadlock.
+ */
+static struct workqueue_struct *cgroup_destroy_wq;
+
+/*
  * Generate an array of cgroup subsystem pointers. At boot time, this is
  * populated with the built in subsystems, and modular subsystems are
  * registered after that. The mutable section of this array is protected by
@@ -191,6 +199,7 @@ static void cgroup_destroy_css_killed(struct cgroup *cgrp);
 static int cgroup_destroy_locked(struct cgroup *cgrp);
 static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
                               bool is_add);
+static int cgroup_file_release(struct inode *inode, struct file *file);
 
 /**
  * cgroup_css - obtain a cgroup's css for the specified subsystem
@@ -871,7 +880,7 @@ static void cgroup_free_rcu(struct rcu_head *head)
         struct cgroup *cgrp = container_of(head, struct cgroup, rcu_head);
 
         INIT_WORK(&cgrp->destroy_work, cgroup_free_fn);
-        schedule_work(&cgrp->destroy_work);
+        queue_work(cgroup_destroy_wq, &cgrp->destroy_work);
 }
 
 static void cgroup_diput(struct dentry *dentry, struct inode *inode)
@@ -881,6 +890,16 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode)
                 struct cgroup *cgrp = dentry->d_fsdata;
 
                 BUG_ON(!(cgroup_is_dead(cgrp)));
+
+                /*
+                 * XXX: cgrp->id is only used to look up css's.  As cgroup
+                 * and css's lifetimes will be decoupled, it should be made
+                 * per-subsystem and moved to css->id so that lookups are
+                 * successful until the target css is released.
+                 */
+                idr_remove(&cgrp->root->cgroup_idr, cgrp->id);
+                cgrp->id = -1;
+
                 call_rcu(&cgrp->rcu_head, cgroup_free_rcu);
         } else {
                 struct cfent *cfe = __d_cfe(dentry);
@@ -2421,7 +2440,7 @@ static const struct file_operations cgroup_seqfile_operations = {
         .read = seq_read,
         .write = cgroup_file_write,
         .llseek = seq_lseek,
-        .release = single_release,
+        .release = cgroup_file_release,
 };
 
 static int cgroup_file_open(struct inode *inode, struct file *file)
@@ -2482,6 +2501,8 @@ static int cgroup_file_release(struct inode *inode, struct file *file)
                 ret = cft->release(inode, file);
         if (css->ss)
                 css_put(css);
+        if (file->f_op == &cgroup_seqfile_operations)
+                single_release(inode, file);
         return ret;
 }
 
@@ -4249,7 +4270,7 @@ static void css_free_rcu_fn(struct rcu_head *rcu_head)
          * css_put().  dput() requires process context which we don't have.
          */
         INIT_WORK(&css->destroy_work, css_free_work_fn);
-        schedule_work(&css->destroy_work);
+        queue_work(cgroup_destroy_wq, &css->destroy_work);
 }
 
 static void css_release(struct percpu_ref *ref)
@@ -4257,6 +4278,7 @@ static void css_release(struct percpu_ref *ref)
         struct cgroup_subsys_state *css =