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, 584 insertions, 0 deletions

diff --git a/fs/xfs/scrub/bitmap.c b/fs/xfs/scrub/bitmap.c
new file mode 100644
index 000000000..c7fa908d9
--- /dev/null
+++ b/fs/xfs/scrub/bitmap.c
@@ -0,0 +1,584 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2018-2023 Oracle.  All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#include "xfs_platform.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_bit.h"
+#include "xfs_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_mount.h"
+#include "xfs_btree.h"
+#include "scrub/scrub.h"
+#include "scrub/bitmap.h"
+
+#include <linux/interval_tree_generic.h>
+
+/* u64 bitmap */
+
+struct xbitmap64_node {
+	struct rb_node	bn_rbnode;
+
+	/* First set bit of this interval and subtree. */
+	uint64_t	bn_start;
+
+	/* Last set bit of this interval. */
+	uint64_t	bn_last;
+
+	/* Last set bit of this subtree.  Do not touch this. */
+	uint64_t	__bn_subtree_last;
+};
+
+/* Define our own interval tree type with uint64_t parameters. */
+
+#define START(node) ((node)->bn_start)
+#define LAST(node)  ((node)->bn_last)
+
+/*
+ * These functions are defined by the INTERVAL_TREE_DEFINE macro, but we'll
+ * forward-declare them anyway for clarity.
+ */
+static inline __maybe_unused void
+xbitmap64_tree_insert(struct xbitmap64_node *node, struct rb_root_cached *root);
+
+static inline __maybe_unused void
+xbitmap64_tree_remove(struct xbitmap64_node *node, struct rb_root_cached *root);
+
+static inline __maybe_unused struct xbitmap64_node *
+xbitmap64_tree_iter_first(struct rb_root_cached *root, uint64_t start,
+			uint64_t last);
+
+static inline __maybe_unused struct xbitmap64_node *
+xbitmap64_tree_iter_next(struct xbitmap64_node *node, uint64_t start,
+		       uint64_t last);
+
+INTERVAL_TREE_DEFINE(struct xbitmap64_node, bn_rbnode, uint64_t,
+		__bn_subtree_last, START, LAST, static inline __maybe_unused,
+		xbitmap64_tree)
+
+/* Iterate each interval of a bitmap.  Do not change the bitmap. */
+#define for_each_xbitmap64_extent(bn, bitmap) \
+	for ((bn) = rb_entry_safe(rb_first(&(bitmap)->xb_root.rb_root), \
+				   struct xbitmap64_node, bn_rbnode); \
+	     (bn) != NULL; \
+	     (bn) = rb_entry_safe(rb_next(&(bn)->bn_rbnode), \
+				   struct xbitmap64_node, bn_rbnode))
+
+/* Clear a range of this bitmap. */
+int
+xbitmap64_clear(
+	struct xbitmap64	*bitmap,
+	uint64_t		start,
+	uint64_t		len)
+{
+	struct xbitmap64_node	*bn;
+	struct xbitmap64_node	*new_bn;
+	uint64_t		last = start + len - 1;
+
+	while ((bn = xbitmap64_tree_iter_first(&bitmap->xb_root, start, last))) {
+		if (bn->bn_start < start && bn->bn_last > last) {
+			uint64_t	old_last = bn->bn_last;
+
+			/* overlaps with the entire clearing range */
+			xbitmap64_tree_remove(bn, &bitmap->xb_root);
+			bn->bn_last = start - 1;
+			xbitmap64_tree_insert(bn, &bitmap->xb_root);
+
+			/* add an extent */
+			new_bn = kmalloc_obj(struct xbitmap64_node,
+					     XCHK_GFP_FLAGS);
+			if (!new_bn)
+				return -ENOMEM;
+			new_bn->bn_start = last + 1;
+			new_bn->bn_last = old_last;
+			xbitmap64_tree_insert(new_bn, &bitmap->xb_root);
+		} else if (bn->bn_start < start) {
+			/* overlaps with the left side of the clearing range */
+			xbitmap64_tree_remove(bn, &bitmap->xb_root);
+			bn->bn_last = start - 1;
+			xbitmap64_tree_insert(bn, &bitmap->xb_root);
+		} else if (bn->bn_last > last) {
+			/* overlaps with the right side of the clearing range */
+			xbitmap64_tree_remove(bn, &bitmap->xb_root);
+			bn->bn_start = last + 1;
+			xbitmap64_tree_insert(bn, &bitmap->xb_root);
+			break;
+		} else {
+			/* in the middle of the clearing range */
+			xbitmap64_tree_remove(bn, &bitmap->xb_root);
+			kfree(bn);
+		}
+	}
+
+	return 0;
+}
+
+/* Set a range of this bitmap. */
+int
+xbitmap64_set(
+	struct xbitmap64	*bitmap,
+	uint64_t		start,
+	uint64_t		len)
+{
+	struct xbitmap64_node	*left;
+	struct xbitmap64_node	*right;
+	uint64_t		last = start + len - 1;
+	int			error;
+
+	/* Is this whole range already set? */
+	left = xbitmap64_tree_iter_first(&bitmap->xb_root, start, last);
+	if (left && left->bn_start <= start && left->bn_last >= last)
+		return 0;
+
+	/* Clear out everything in the range we want to set. */
+	error = xbitmap64_clear(bitmap, start, len);
+	if (error)
+		return error;
+
+	/* Do we have a left-adjacent extent? */
+	left = xbitmap64_tree_iter_first(&bitmap->xb_root, start - 1, start - 1);
+	ASSERT(!left || left->bn_last + 1 == start);
+
+	/* Do we have a right-adjacent extent? */
+	right = xbitmap64_tree_iter_first(&bitmap->xb_root, last + 1, last + 1);
+	ASSERT(!right || right->bn_start == last + 1);
+
+	if (left && right) {
+		/* combine left and right adjacent extent */
+		xbitmap64_tree_remove(left, &bitmap->xb_root);
+		xbitmap64_tree_remove(right, &bitmap->xb_root);
+		left->bn_last = right->bn_last;
+		xbitmap64_tree_insert(left, &bitmap->xb_root);
+		kfree(right);
+	} else if (left) {
+		/* combine with left extent */
+		xbitmap64_tree_remove(left, &bitmap->xb_root);
+		left->bn_last = last;
+		xbitmap64_tree_insert(left, &bitmap->xb_root);
+	} else if (right) {
+		/* combine with right extent */
+		xbitmap64_tree_remove(right, &bitmap->xb_root);
+		right->bn_start = start;
+		xbitmap64_tree_insert(right, &bitmap->xb_root);
+	} else {
+		/* add an extent */
+		left = kmalloc_obj(struct xbitmap64_node, XCHK_GFP_FLAGS);
+		if (!left)
+			return -ENOMEM;
+		left->bn_start = start;
+		left->bn_last = last;
+		xbitmap64_tree_insert(left, &bitmap->xb_root);
+	}
+
+	return 0;
+}
+
+/* Free everything related to this bitmap. */
+void
+xbitmap64_destroy(
+	struct xbitmap64	*bitmap)
+{
+	struct xbitmap64_node	*bn;
+
+	while ((bn = xbitmap64_tree_iter_first(&bitmap->xb_root, 0, -1ULL))) {
+		xbitmap64_tree_remove(bn, &bitmap->xb_root);
+		kfree(bn);
+	}
+}
+
+/* Set up a per-AG block bitmap. */
+void
+xbitmap64_init(
+	struct xbitmap64	*bitmap)
+{
+	bitmap->xb_root = RB_ROOT_CACHED;
+}
+
+/*
+ * Remove all the blocks mentioned in @sub from the extents in @bitmap.
+ *
+ * The intent is that callers will iterate the rmapbt for all of its records
+ * for a given owner to generate @bitmap; and iterate all the blocks of the
+ * metadata structures that are not being rebuilt and have the same rmapbt
+ * owner to generate @sub.  This routine subtracts all the extents
+ * mentioned in sub from all the extents linked in @bitmap, which leaves
+ * @bitmap as the list of blocks that are not accounted for, which we assume
+ * are the dead blocks of the old metadata structure.  The blocks mentioned in
+ * @bitmap can be reaped.
+ *
+ * This is the logical equivalent of bitmap &= ~sub.
+ */
+int
+xbitmap64_disunion(
+	struct xbitmap64	*bitmap,
+	struct xbitmap64	*sub)
+{
+	struct xbitmap64_node	*bn;
+	int			error;
+
+	if (xbitmap64_empty(bitmap) || xbitmap64_empty(sub))
+		return 0;
+
+	for_each_xbitmap64_extent(bn, sub) {
+		error = xbitmap64_clear(bitmap, bn->bn_start,
+				bn->bn_last - bn->bn_start + 1);
+		if (error)
+			return error;
+	}
+
+	return 0;
+}
+
+/* How many bits are set in this bitmap? */
+uint64_t
+xbitmap64_hweight(
+	struct xbitmap64	*bitmap)
+{
+	struct xbitmap64_node	*bn;
+	uint64_t		ret = 0;
+
+	for_each_xbitmap64_extent(bn, bitmap)
+		ret += bn->bn_last - bn->bn_start + 1;
+
+	return ret;
+}
+
+/* Call a function for every run of set bits in this bitmap. */
+int
+xbitmap64_walk(
+	struct xbitmap64	*bitmap,
+	xbitmap64_walk_fn		fn,
+	void			*priv)
+{
+	struct xbitmap64_node	*bn;
+	int			error = 0;
+
+	for_each_xbitmap64_extent(bn, bitmap) {
+		error = fn(bn->bn_start, bn->bn_last - bn->bn_start + 1, priv);
+		if (error)
+			break;
+	}
+
+	return error;
+}
+
+/* Does this bitmap have no bits set at all? */
+bool
+xbitmap64_empty(
+	struct xbitmap64	*bitmap)
+{
+	return bitmap->xb_root.rb_root.rb_node == NULL;
+}
+
+/* Is the start of the range set or clear?  And for how long? */
+bool
+xbitmap64_test(
+	struct xbitmap64	*bitmap,
+	uint64_t		start,
+	uint64_t		*len)
+{
+	struct xbitmap64_node	*bn;
+	uint64_t		last = start + *len - 1;
+
+	bn = xbitmap64_tree_iter_first(&bitmap->xb_root, start, last);
+	if (!bn)
+		return false;
+	if (bn->bn_start <= start) {
+		if (bn->bn_last < last)
+			*len = bn->bn_last - start + 1;
+		return true;
+	}
+	*len = bn->bn_start - start;
+	return false;
+}
+
+/* u32 bitmap */
+
+struct xbitmap32_node {
+	struct rb_node	bn_rbnode;
+
+	/* First set bit of this interval and subtree. */
+	uint32_t	bn_start;
+
+	/* Last set bit of this interval. */
+	uint32_t	bn_last;
+
+	/* Last set bit of this subtree.  Do not touch this. */
+	uint32_t	__bn_subtree_last;
+};
+
+/* Define our own interval tree type with uint32_t parameters. */
+
+/*
+ * These functions are defined by the INTERVAL_TREE_DEFINE macro, but we'll
+ * forward-declare them anyway for clarity.
+ */
+static inline __maybe_unused void
+xbitmap32_tree_insert(struct xbitmap32_node *node, struct rb_root_cached *root);
+
+static inline __maybe_unused void
+xbitmap32_tree_remove(struct xbitmap32_node *node, struct rb_root_cached *root);
+
+static inline __maybe_unused struct xbitmap32_node *
+xbitmap32_tree_iter_first(struct rb_root_cached *root, uint32_t start,
+			  uint32_t last);
+
+static inline __maybe_unused struct xbitmap32_node *
+xbitmap32_tree_iter_next(struct xbitmap32_node *node, uint32_t start,
+			 uint32_t last);
+
+INTERVAL_TREE_DEFINE(struct xbitmap32_node, bn_rbnode, uint32_t,
+		__bn_subtree_last, START, LAST, static inline __maybe_unused,
+		xbitmap32_tree)
+
+/* Iterate each interval of a bitmap.  Do not change the bitmap. */
+#define for_each_xbitmap32_extent(bn, bitmap) \
+	for ((bn) = rb_entry_safe(rb_first(&(bitmap)->xb_root.rb_root), \
+				   struct xbitmap32_node, bn_rbnode); \
+	     (bn) != NULL; \
+	     (bn) = rb_entry_safe(rb_next(&(bn)->bn_rbnode), \
+				   struct xbitmap32_node, bn_rbnode))
+
+/* Clear a range of this bitmap. */
+int
+xbitmap32_clear(
+	struct xbitmap32	*bitmap,
+	uint32_t		start,
+	uint32_t		len)
+{
+	struct xbitmap32_node	*bn;
+	struct xbitmap32_node	*new_bn;
+	uint32_t		last = start + len - 1;
+
+	while ((bn = xbitmap32_tree_iter_first(&bitmap->xb_root, start, last))) {
+		if (bn->bn_start < start && bn->bn_last > last) {
+			uint32_t	old_last = bn->bn_last;
+
+			/* overlaps with the entire clearing range */
+			xbitmap32_tree_remove(bn, &bitmap->xb_root);
+			bn->bn_last = start - 1;
+			xbitmap32_tree_insert(bn, &bitmap->xb_root);
+
+			/* add an extent */
+			new_bn = kmalloc_obj(struct xbitmap32_node,
+					     XCHK_GFP_FLAGS);
+			if (!new_bn)
+				return -ENOMEM;
+			new_bn->bn_start = last + 1;
+			new_bn->bn_last = old_last;
+			xbitmap32_tree_insert(new_bn, &bitmap->xb_root);
+		} else if (bn->bn_start < start) {
+			/* overlaps with the left side of the clearing range */
+			xbitmap32_tree_remove(bn, &bitmap->xb_root);
+			bn->bn_last = start - 1;
+			xbitmap32_tree_insert(bn, &bitmap->xb_root);
+		} else if (bn->bn_last > last) {
+			/* overlaps with the right side of the clearing range */
+			xbitmap32_tree_remove(bn, &bitmap->xb_root);
+			bn->bn_start = last + 1;
+			xbitmap32_tree_insert(bn, &bitmap->xb_root);
+			break;
+		} else {
+			/* in the middle of the clearing range */
+			xbitmap32_tree_remove(bn, &bitmap->xb_root);
+			kfree(bn);
+		}
+	}
+
+	return 0;
+}
+
+/* Set a range of this bitmap. */
+int
+xbitmap32_set(
+	struct xbitmap32	*bitmap,
+	uint32_t		start,
+	uint32_t		len)
+{
+	struct xbitmap32_node	*left;
+	struct xbitmap32_node	*right;
+	uint32_t		last = start + len - 1;
+	int			error;
+
+	/* Is this whole range already set? */
+	left = xbitmap32_tree_iter_first(&bitmap->xb_root, start, last);
+	if (left && left->bn_start <= start && left->bn_last >= last)
+		return 0;
+
+	/* Clear out everything in the range we want to set. */
+	error = xbitmap32_clear(bitmap, start, len);
+	if (error)
+		return error;
+
+	/* Do we have a left-adjacent extent? */
+	left = xbitmap32_tree_iter_first(&bitmap->xb_root, start - 1, start - 1);
+	ASSERT(!left || left->bn_last + 1 == start);
+
+	/* Do we have a right-adjacent extent? */
+	right = xbitmap32_tree_iter_first(&bitmap->xb_root, last + 1, last + 1);
+	ASSERT(!right || right->bn_start == last + 1);
+
+	if (left && right) {
+		/* combine left and right adjacent extent */
+		xbitmap32_tree_remove(left, &bitmap->xb_root);
+		xbitmap32_tree_remove(right, &bitmap->xb_root);
+		left->bn_last = right->bn_last;
+		xbitmap32_tree_insert(left, &bitmap->xb_root);
+		kfree(right);
+	} else if (left) {
+		/* combine with left extent */
+		xbitmap32_tree_remove(left, &bitmap->xb_root);
+		left->bn_last = last;
+		xbitmap32_tree_insert(left, &bitmap->xb_root);
+	} else if (right) {
+		/* combine with right extent */
+		xbitmap32_tree_remove(right, &bitmap->xb_root);
+		right->bn_start = start;
+		xbitmap32_tree_insert(right, &bitmap->xb_root);
+	} else {
+		/* add an extent */
+		left = kmalloc_obj(struct xbitmap32_node, XCHK_GFP_FLAGS);
+		if (!left)
+			return -ENOMEM;
+		left->bn_start = start;
+		left->bn_last = last;
+		xbitmap32_tree_insert(left, &bitmap->xb_root);
+	}
+
+	return 0;
+}
+
+/* Free everything related to this bitmap. */
+void
+xbitmap32_destroy(
+	struct xbitmap32	*bitmap)
+{
+	struct xbitmap32_node	*bn;
+
+	while ((bn = xbitmap32_tree_iter_first(&bitmap->xb_root, 0, -1U))) {
+		xbitmap32_tree_remove(bn, &bitmap->xb_root);
+		kfree(bn);
+	}
+}
+
+/* Set up a per-AG block bitmap. */
+void
+xbitmap32_init(
+	struct xbitmap32	*bitmap)
+{
+	bitmap->xb_root = RB_ROOT_CACHED;
+}
+
+/*
+ * Remove all the blocks mentioned in @sub from the extents in @bitmap.
+ *
+ * The intent is that callers will iterate the rmapbt for all of its records
+ * for a given owner to generate @bitmap; and iterate all the blocks of the
+ * metadata structures that are not being rebuilt and have the same rmapbt
+ * owner to generate @sub.  This routine subtracts all the extents
+ * mentioned in sub from all the extents linked in @bitmap, which leaves
+ * @bitmap as the list of blocks that are not accounted for, which we assume
+ * are the dead blocks of the old metadata structure.  The blocks mentioned in
+ * @bitmap can be reaped.
+ *
+ * This is the logical equivalent of bitmap &= ~sub.
+ */
+int
+xbitmap32_disunion(
+	struct xbitmap32	*bitmap,
+	struct xbitmap32	*sub)
+{
+	struct xbitmap32_node	*bn;
+	int			error;
+
+	if (xbitmap32_empty(bitmap) || xbitmap32_empty(sub))
+		return 0;
+
+	for_each_xbitmap32_extent(bn, sub) {
+		error = xbitmap32_clear(bitmap, bn->bn_start,
+				bn->bn_last - bn->bn_start + 1);
+		if (error)
+			return error;
+	}
+
+	return 0;
+}
+
+/* How many bits are set in this bitmap? */
+uint32_t
+xbitmap32_hweight(
+	struct xbitmap32	*bitmap)
+{
+	struct xbitmap32_node	*bn;
+	uint32_t		ret = 0;
+
+	for_each_xbitmap32_extent(bn, bitmap)
+		ret += bn->bn_last - bn->bn_start + 1;
+
+	return ret;
+}
+
+/* Call a function for every run of set bits in this bitmap. */
+int
+xbitmap32_walk(
+	struct xbitmap32	*bitmap,
+	xbitmap32_walk_fn	fn,
+	void			*priv)
+{
+	struct xbitmap32_node	*bn;
+	int			error = 0;
+
+	for_each_xbitmap32_extent(bn, bitmap) {
+		error = fn(bn->bn_start, bn->bn_last - bn->bn_start + 1, priv);
+		if (error)
+			break;
+	}
+
+	return error;
+}
+
+/* Does this bitmap have no bits set at all? */
+bool
+xbitmap32_empty(
+	struct xbitmap32	*bitmap)
+{
+	return bitmap->xb_root.rb_root.rb_node == NULL;
+}
+
+/* Is the start of the range set or clear?  And for how long? */
+bool
+xbitmap32_test(
+	struct xbitmap32	*bitmap,
+	uint32_t		start,
+	uint32_t		*len)
+{
+	struct xbitmap32_node	*bn;
+	uint32_t		last = start + *len - 1;
+
+	bn = xbitmap32_tree_iter_first(&bitmap->xb_root, start, last);
+	if (!bn)
+		return false;
+	if (bn->bn_start <= start) {
+		if (bn->bn_last < last)
+			*len = bn->bn_last - start + 1;
+		return true;
+	}
+	*len = bn->bn_start - start;
+	return false;
+}
+
+/* Count the number of set regions in this bitmap. */
+uint32_t
+xbitmap32_count_set_regions(
+	struct xbitmap32	*bitmap)
+{
+	struct xbitmap32_node	*bn;
+	uint32_t		nr = 0;
+
+	for_each_xbitmap32_extent(bn, bitmap)
+		nr++;
+
+	return nr;
+}