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, 351 insertions, 0 deletions

diff --git a/sound/firewire/cmp.c b/sound/firewire/cmp.c
new file mode 100644
index 000000000..b2b76c7c7
--- /dev/null
+++ b/sound/firewire/cmp.c
@@ -0,0 +1,351 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Connection Management Procedures (IEC 61883-1) helper functions
+ *
+ * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
+ */
+
+#include <linux/device.h>
+#include <linux/firewire.h>
+#include <linux/firewire-constants.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include "lib.h"
+#include "iso-resources.h"
+#include "cmp.h"
+
+/* MPR common fields */
+#define MPR_SPEED_MASK		0xc0000000
+#define MPR_SPEED_SHIFT		30
+#define MPR_XSPEED_MASK		0x00000060
+#define MPR_XSPEED_SHIFT	5
+#define MPR_PLUGS_MASK		0x0000001f
+
+/* PCR common fields */
+#define PCR_ONLINE		0x80000000
+#define PCR_BCAST_CONN		0x40000000
+#define PCR_P2P_CONN_MASK	0x3f000000
+#define PCR_P2P_CONN_SHIFT	24
+#define PCR_CHANNEL_MASK	0x003f0000
+#define PCR_CHANNEL_SHIFT	16
+
+/* oPCR specific fields */
+#define OPCR_XSPEED_MASK	0x00C00000
+#define OPCR_XSPEED_SHIFT	22
+#define OPCR_SPEED_MASK		0x0000C000
+#define OPCR_SPEED_SHIFT	14
+#define OPCR_OVERHEAD_ID_MASK	0x00003C00
+#define OPCR_OVERHEAD_ID_SHIFT	10
+
+enum bus_reset_handling {
+	ABORT_ON_BUS_RESET,
+	SUCCEED_ON_BUS_RESET,
+};
+
+static __printf(2, 3)
+void cmp_error(struct cmp_connection *c, const char *fmt, ...)
+{
+	va_list va;
+
+	va_start(va, fmt);
+	dev_err(&c->resources.unit->device, "%cPCR%u: %pV",
+		(c->direction == CMP_INPUT) ? 'i' : 'o',
+		c->pcr_index, &(struct va_format){ fmt, &va });
+	va_end(va);
+}
+
+static u64 mpr_address(struct cmp_connection *c)
+{
+	if (c->direction == CMP_INPUT)
+		return CSR_REGISTER_BASE + CSR_IMPR;
+	else
+		return CSR_REGISTER_BASE + CSR_OMPR;
+}
+
+static u64 pcr_address(struct cmp_connection *c)
+{
+	if (c->direction == CMP_INPUT)
+		return CSR_REGISTER_BASE + CSR_IPCR(c->pcr_index);
+	else
+		return CSR_REGISTER_BASE + CSR_OPCR(c->pcr_index);
+}
+
+static int pcr_modify(struct cmp_connection *c,
+		      __be32 (*modify)(struct cmp_connection *c, __be32 old),
+		      int (*check)(struct cmp_connection *c, __be32 pcr),
+		      enum bus_reset_handling bus_reset_handling)
+{
+	__be32 old_arg, buffer[2];
+	int err;
+
+	buffer[0] = c->last_pcr_value;
+	for (;;) {
+		old_arg = buffer[0];
+		buffer[1] = modify(c, buffer[0]);
+
+		err = snd_fw_transaction(
+				c->resources.unit, TCODE_LOCK_COMPARE_SWAP,
+				pcr_address(c), buffer, 8,
+				FW_FIXED_GENERATION | c->resources.generation);
+
+		if (err < 0) {
+			if (err == -EAGAIN &&
+			    bus_reset_handling == SUCCEED_ON_BUS_RESET)
+				err = 0;
+			return err;
+		}
+
+		if (buffer[0] == old_arg) /* success? */
+			break;
+
+		if (check) {
+			err = check(c, buffer[0]);
+			if (err < 0)
+				return err;
+		}
+	}
+	c->last_pcr_value = buffer[1];
+
+	return 0;
+}
+
+
+/**
+ * cmp_connection_init - initializes a connection manager
+ * @c: the connection manager to initialize
+ * @unit: a unit of the target device
+ * @direction: input or output
+ * @pcr_index: the index of the iPCR/oPCR on the target device
+ */
+int cmp_connection_init(struct cmp_connection *c,
+			struct fw_unit *unit,
+			enum cmp_direction direction,
+			unsigned int pcr_index)
+{
+	__be32 mpr_be;
+	u32 mpr;
+	int err;
+
+	c->direction = direction;
+	err = snd_fw_transaction(unit, TCODE_READ_QUADLET_REQUEST,
+				 mpr_address(c), &mpr_be, 4, 0);
+	if (err < 0)
+		return err;
+	mpr = be32_to_cpu(mpr_be);
+
+	if (pcr_index >= (mpr & MPR_PLUGS_MASK))
+		return -EINVAL;
+
+	err = fw_iso_resources_init(&c->resources, unit);
+	if (err < 0)
+		return err;
+
+	c->connected = false;
+	mutex_init(&c->mutex);
+	c->last_pcr_value = cpu_to_be32(0x80000000);
+	c->pcr_index = pcr_index;
+	c->max_speed = (mpr & MPR_SPEED_MASK) >> MPR_SPEED_SHIFT;
+	if (c->max_speed == SCODE_BETA)
+		c->max_speed += (mpr & MPR_XSPEED_MASK) >> MPR_XSPEED_SHIFT;
+
+	return 0;
+}
+EXPORT_SYMBOL(cmp_connection_init);
+
+/**
+ * cmp_connection_check_used - check connection is already esablished or not
+ * @c: the connection manager to be checked
+ * @used: the pointer to store the result of checking the connection
+ */
+int cmp_connection_check_used(struct cmp_connection *c, bool *used)
+{
+	__be32 pcr;
+	int err;
+
+	err = snd_fw_transaction(
+			c->resources.unit, TCODE_READ_QUADLET_REQUEST,
+			pcr_address(c), &pcr, 4, 0);
+	if (err >= 0)
+		*used = !!(pcr & cpu_to_be32(PCR_BCAST_CONN |
+					     PCR_P2P_CONN_MASK));
+
+	return err;
+}
+EXPORT_SYMBOL(cmp_connection_check_used);
+
+/**
+ * cmp_connection_destroy - free connection manager resources
+ * @c: the connection manager
+ */
+void cmp_connection_destroy(struct cmp_connection *c)
+{
+	WARN_ON(c->connected);
+	mutex_destroy(&c->mutex);
+	fw_iso_resources_destroy(&c->resources);
+}
+EXPORT_SYMBOL(cmp_connection_destroy);
+
+int cmp_connection_reserve(struct cmp_connection *c,
+			   unsigned int max_payload_bytes)
+{
+	guard(mutex)(&c->mutex);
+
+	if (WARN_ON(c->resources.allocated))
+		return -EBUSY;
+
+	c->speed = min(c->max_speed,
+		       fw_parent_device(c->resources.unit)->max_speed);
+
+	return fw_iso_resources_allocate(&c->resources, max_payload_bytes,
+					 c->speed);
+}
+EXPORT_SYMBOL(cmp_connection_reserve);
+
+void cmp_connection_release(struct cmp_connection *c)
+{
+	guard(mutex)(&c->mutex);
+	fw_iso_resources_free(&c->resources);
+}
+EXPORT_SYMBOL(cmp_connection_release);
+
+static __be32 ipcr_set_modify(struct cmp_connection *c, __be32 ipcr)
+{
+	ipcr &= ~cpu_to_be32(PCR_BCAST_CONN |
+			     PCR_P2P_CONN_MASK |
+			     PCR_CHANNEL_MASK);
+	ipcr |= cpu_to_be32(1 << PCR_P2P_CONN_SHIFT);
+	ipcr |= cpu_to_be32(c->resources.channel << PCR_CHANNEL_SHIFT);
+
+	return ipcr;
+}
+
+static int get_overhead_id(struct cmp_connection *c)
+{
+	int id;
+
+	/*
+	 * apply "oPCR overhead ID encoding"
+	 * the encoding table can convert up to 512.
+	 * here the value over 512 is converted as the same way as 512.
+	 */
+	for (id = 1; id < 16; id++) {
+		if (c->resources.bandwidth_overhead < (id << 5))
+			break;
+	}
+	if (id == 16)
+		id = 0;
+
+	return id;
+}
+
+static __be32 opcr_set_modify(struct cmp_connection *c, __be32 opcr)
+{
+	unsigned int spd, xspd;
+
+	/* generate speed and extended speed field value */
+	if (c->speed > SCODE_400) {
+		spd  = SCODE_800;
+		xspd = c->speed - SCODE_800;
+	} else {
+		spd = c->speed;
+		xspd = 0;
+	}
+
+	opcr &= ~cpu_to_be32(PCR_BCAST_CONN |
+			     PCR_P2P_CONN_MASK |
+			     OPCR_XSPEED_MASK |
+			     PCR_CHANNEL_MASK |
+			     OPCR_SPEED_MASK |
+			     OPCR_OVERHEAD_ID_MASK);
+	opcr |= cpu_to_be32(1 << PCR_P2P_CONN_SHIFT);
+	opcr |= cpu_to_be32(xspd << OPCR_XSPEED_SHIFT);
+	opcr |= cpu_to_be32(c->resources.channel << PCR_CHANNEL_SHIFT);
+	opcr |= cpu_to_be32(spd << OPCR_SPEED_SHIFT);
+	opcr |= cpu_to_be32(get_overhead_id(c) << OPCR_OVERHEAD_ID_SHIFT);
+
+	return opcr;
+}
+
+static int pcr_set_check(struct cmp_connection *c, __be32 pcr)
+{
+	if (pcr & cpu_to_be32(PCR_BCAST_CONN |
+			      PCR_P2P_CONN_MASK)) {
+		cmp_error(c, "plug is already in use\n");
+		return -EBUSY;
+	}
+	if (!(pcr & cpu_to_be32(PCR_ONLINE))) {
+		cmp_error(c, "plug is not on-line\n");
+		return -ECONNREFUSED;
+	}
+
+	return 0;
+}
+
+/**
+ * cmp_connection_establish - establish a connection to the target
+ * @c: the connection manager
+ *
+ * This function establishes a point-to-point connection from the local
+ * computer to the target by allocating isochronous resources (channel and
+ * bandwidth) and setting the target's input/output plug control register.
+ * When this function succeeds, the caller is responsible for starting
+ * transmitting packets.
+ */
+int cmp_connection_establish(struct cmp_connection *c)
+{
+	int err;
+
+	guard(mutex)(&c->mutex);
+
+	if (WARN_ON(c->connected))
+		return -EISCONN;
+
+retry_after_bus_reset:
+	if (c->direction == CMP_OUTPUT)
+		err = pcr_modify(c, opcr_set_modify, pcr_set_check,
+				 ABORT_ON_BUS_RESET);
+	else
+		err = pcr_modify(c, ipcr_set_modify, pcr_set_check,
+				 ABORT_ON_BUS_RESET);
+
+	if (err == -EAGAIN) {
+		err = fw_iso_resources_update(&c->resources);
+		if (err >= 0)
+			goto retry_after_bus_reset;
+	}
+	if (err >= 0)
+		c->connected = true;
+
+	return err;
+}
+EXPORT_SYMBOL(cmp_connection_establish);
+
+static __be32 pcr_break_modify(struct cmp_connection *c, __be32 pcr)
+{
+	return pcr & ~cpu_to_be32(PCR_BCAST_CONN | PCR_P2P_CONN_MASK);
+}
+
+/**
+ * cmp_connection_break - break the connection to the target
+ * @c: the connection manager
+ *
+ * This function deactives the connection in the target's input/output plug
+ * control register, and frees the isochronous resources of the connection.
+ * Before calling this function, the caller should cease transmitting packets.
+ */
+void cmp_connection_break(struct cmp_connection *c)
+{
+	int err;
+
+	guard(mutex)(&c->mutex);
+
+	if (!c->connected)
+		return;
+
+	err = pcr_modify(c, pcr_break_modify, NULL, SUCCEED_ON_BUS_RESET);
+	if (err < 0)
+		cmp_error(c, "plug is still connected\n");
+
+	c->connected = false;
+}
+EXPORT_SYMBOL(cmp_connection_break);