Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 269 insertions, 0 deletions

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.h b/fs/nfs/flexfilelayout/flexfilelayout.h
new file mode 100644
index 000000000..a5bd00f69
--- /dev/null
+++ b/fs/nfs/flexfilelayout/flexfilelayout.h
@@ -0,0 +1,269 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * NFSv4 flexfile layout driver data structures.
+ *
+ * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
+ *
+ * Tao Peng <bergwolf@primarydata.com>
+ */
+
+#ifndef FS_NFS_NFS4FLEXFILELAYOUT_H
+#define FS_NFS_NFS4FLEXFILELAYOUT_H
+
+#define FF_FLAGS_NO_LAYOUTCOMMIT 1
+#define FF_FLAGS_NO_IO_THRU_MDS  2
+#define FF_FLAGS_NO_READ_IO      4
+
+#include <linux/refcount.h>
+#include "../pnfs.h"
+
+/* XXX: Let's filter out insanely large mirror count for now to avoid oom
+ * due to network error etc. */
+#define NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT 4096
+
+#define NFS4_FLEXFILE_LAYOUT_MAX_STRIPE_CNT 4096
+
+/* LAYOUTSTATS report interval in ms */
+#define FF_LAYOUTSTATS_REPORT_INTERVAL (60000L)
+#define FF_LAYOUTSTATS_MAXDEV 4
+
+struct nfs4_ff_ds_version {
+	u32				version;
+	u32				minor_version;
+	u32				rsize;
+	u32				wsize;
+	bool				tightly_coupled;
+};
+
+/* chained in global deviceid hlist */
+struct nfs4_ff_layout_ds {
+	struct nfs4_deviceid_node	id_node;
+	u32				ds_versions_cnt;
+	struct nfs4_ff_ds_version	*ds_versions;
+	struct nfs4_pnfs_ds		*ds;
+};
+
+struct nfs4_ff_layout_ds_err {
+	struct list_head		list; /* linked in mirror error_list */
+	u64				offset;
+	u64				length;
+	int				status;
+	enum nfs_opnum4			opnum;
+	nfs4_stateid			stateid;
+	struct nfs4_deviceid		deviceid;
+};
+
+struct nfs4_ff_io_stat {
+	__u64				ops_requested;
+	__u64				bytes_requested;
+	__u64				ops_completed;
+	__u64				bytes_completed;
+	__u64				bytes_not_delivered;
+	ktime_t				total_busy_time;
+	ktime_t				aggregate_completion_time;
+};
+
+struct nfs4_ff_busy_timer {
+	ktime_t start_time;
+	atomic_t n_ops;
+};
+
+struct nfs4_ff_layoutstat {
+	struct nfs4_ff_io_stat io_stat;
+	struct nfs4_ff_busy_timer busy_timer;
+};
+
+struct nfs4_ff_layout_mirror;
+
+struct nfs4_ff_layout_ds_stripe {
+	struct nfs4_ff_layout_mirror   *mirror;
+	struct nfs4_deviceid		devid;
+	u32				efficiency;
+	struct nfs4_ff_layout_ds	*mirror_ds;
+	u32				fh_versions_cnt;
+	struct nfs_fh			*fh_versions;
+	nfs4_stateid			stateid;
+	const struct cred __rcu		*ro_cred;
+	const struct cred __rcu		*rw_cred;
+	struct nfs_file_localio		nfl;
+	struct nfs4_ff_layoutstat	read_stat;
+	struct nfs4_ff_layoutstat	write_stat;
+	ktime_t				start_time;
+};
+
+struct nfs4_ff_layout_mirror {
+	struct pnfs_layout_hdr		*layout;
+	struct list_head		mirrors;
+	u32				dss_count;
+	struct nfs4_ff_layout_ds_stripe *dss;
+	refcount_t			ref;
+	spinlock_t			lock;
+	unsigned long			flags;
+	u32				report_interval;
+};
+
+#define NFS4_FF_MIRROR_STAT_AVAIL	(0)
+
+struct nfs4_ff_layout_segment {
+	struct pnfs_layout_segment	generic_hdr;
+	u64				stripe_unit;
+	u32				flags;
+	u32				mirror_array_cnt;
+	struct nfs4_ff_layout_mirror	*mirror_array[] __counted_by(mirror_array_cnt);
+};
+
+/* nfs4_flexfile_layout::flags bit indices */
+#define NFS4_FF_HDR_NO_IO_THRU_MDS  0   /* any lseg has had FF_FLAGS_NO_IO_THRU_MDS */
+
+struct nfs4_flexfile_layout {
+	struct pnfs_layout_hdr generic_hdr;
+	struct pnfs_ds_commit_info commit_info;
+	struct list_head	mirrors;
+	struct list_head	error_list; /* nfs4_ff_layout_ds_err */
+	ktime_t			last_report_time; /* Layoutstat report times */
+	unsigned long		flags;
+};
+
+struct nfs4_flexfile_layoutreturn_args {
+	struct list_head errors;
+	struct nfs42_layoutstat_devinfo devinfo[FF_LAYOUTSTATS_MAXDEV];
+	unsigned int num_errors;
+	unsigned int num_dev;
+	struct page *pages[1];
+};
+
+static inline struct nfs4_flexfile_layout *
+FF_LAYOUT_FROM_HDR(struct pnfs_layout_hdr *lo)
+{
+	return container_of(lo, struct nfs4_flexfile_layout, generic_hdr);
+}
+
+static inline struct nfs4_ff_layout_segment *
+FF_LAYOUT_LSEG(struct pnfs_layout_segment *lseg)
+{
+	return container_of(lseg,
+			    struct nfs4_ff_layout_segment,
+			    generic_hdr);
+}
+
+static inline struct nfs4_ff_layout_ds *
+FF_LAYOUT_MIRROR_DS(struct nfs4_deviceid_node *node)
+{
+	return container_of(node, struct nfs4_ff_layout_ds, id_node);
+}
+
+static inline struct nfs4_ff_layout_mirror *
+FF_LAYOUT_COMP(struct pnfs_layout_segment *lseg, u32 idx)
+{
+	struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
+
+	if (idx < fls->mirror_array_cnt)
+		return fls->mirror_array[idx];
+	return NULL;
+}
+
+static inline struct nfs4_deviceid_node *
+FF_LAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg, u32 idx, u32 dss_id)
+{
+	struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, idx);
+
+	if (mirror != NULL) {
+		struct nfs4_ff_layout_ds *mirror_ds = mirror->dss[dss_id].mirror_ds;
+
+		if (!IS_ERR_OR_NULL(mirror_ds))
+			return &mirror_ds->id_node;
+	}
+	return NULL;
+}
+
+static inline u32
+FF_LAYOUT_MIRROR_COUNT(struct pnfs_layout_segment *lseg)
+{
+	return FF_LAYOUT_LSEG(lseg)->mirror_array_cnt;
+}
+
+static inline bool
+ff_layout_no_fallback_to_mds(struct pnfs_layout_segment *lseg)
+{
+	return FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_IO_THRU_MDS;
+}
+
+/*
+ * Sticky hdr-level mirror of FF_FLAGS_NO_IO_THRU_MDS so callers that have
+ * no current lseg (e.g. between LAYOUTRETURN and the next LAYOUTGET) can
+ * still honor the no-MDS-fallback policy.
+ */
+static inline bool
+ff_layout_hdr_no_fallback_to_mds(struct pnfs_layout_hdr *lo)
+{
+	return test_bit(NFS4_FF_HDR_NO_IO_THRU_MDS,
+			&FF_LAYOUT_FROM_HDR(lo)->flags);
+}
+
+static inline bool
+ff_layout_no_read_on_rw(struct pnfs_layout_segment *lseg)
+{
+	return FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_READ_IO;
+}
+
+static inline int
+nfs4_ff_layout_ds_version(const struct nfs4_ff_layout_mirror *mirror, u32 dss_id)
+{
+	return mirror->dss[dss_id].mirror_ds->ds_versions[0].version;
+}
+
+static inline u32
+nfs4_ff_layout_calc_dss_id(const u64 stripe_unit, const u32 dss_count, const loff_t offset)
+{
+	u64 tmp = offset;
+
+	if (dss_count == 1 || stripe_unit == 0)
+		return 0;
+
+	do_div(tmp, stripe_unit);
+
+	return do_div(tmp, dss_count);
+}
+
+struct nfs4_ff_layout_ds *
+nfs4_ff_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
+			    gfp_t gfp_flags);
+void nfs4_ff_layout_put_deviceid(struct nfs4_ff_layout_ds *mirror_ds);
+void nfs4_ff_layout_free_deviceid(struct nfs4_ff_layout_ds *mirror_ds);
+int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
+			     struct nfs4_ff_layout_mirror *mirror,
+			     u32 dss_id, u64 offset, u64 length, int status,
+			     enum nfs_opnum4 opnum, gfp_t gfp_flags);
+void ff_layout_send_layouterror(struct pnfs_layout_segment *lseg);
+int ff_layout_encode_ds_ioerr(struct xdr_stream *xdr, const struct list_head *head);
+void ff_layout_free_ds_ioerr(struct list_head *head);
+unsigned int ff_layout_fetch_ds_ioerr(struct pnfs_layout_hdr *lo,
+		const struct pnfs_layout_range *range,
+		struct list_head *head,
+		unsigned int maxnum);
+struct nfs_fh *
+nfs4_ff_layout_select_ds_fh(struct nfs4_ff_layout_mirror *mirror, u32 dss_id);
+void
+nfs4_ff_layout_select_ds_stateid(const struct nfs4_ff_layout_mirror *mirror,
+				 u32 dss_id,
+				 nfs4_stateid *stateid);
+
+struct nfs4_pnfs_ds *
+nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg,
+			  struct nfs4_ff_layout_mirror *mirror,
+			  u32 dss_id,
+			  bool fail_return);
+
+struct rpc_clnt *
+nfs4_ff_find_or_create_ds_client(struct nfs4_ff_layout_mirror *mirror,
+				 struct nfs_client *ds_clp,
+				 struct inode *inode,
+				 u32 dss_id);
+const struct cred *ff_layout_get_ds_cred(struct nfs4_ff_layout_mirror *mirror,
+					 const struct pnfs_layout_range *range,
+					 const struct cred *mdscred,
+					 u32 dss_id);
+bool ff_layout_avoid_mds_available_ds(struct pnfs_layout_segment *lseg);
+bool ff_layout_avoid_read_on_rw(struct pnfs_layout_segment *lseg);
+
+#endif /* FS_NFS_NFS4FLEXFILELAYOUT_H */