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authorPaolo Bonzini <pbonzini@redhat.com>2021-05-17 09:55:12 +0200
committerPaolo Bonzini <pbonzini@redhat.com>2021-05-17 09:55:12 +0200
commita4345a7cecfb91ae78cd43d26b0c6a956420761a (patch)
treeb0cf6296f791fa250ccc9d419c46f48fb73c331b /kernel/gcov/fs.c
parentce7ea0cfdc2e9ff31d12da31c3226deddb9644f5 (diff)
parentcb853ded1d25e5b026ce115dbcde69e3d7e2e831 (diff)
Merge tag 'kvmarm-fixes-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 fixes for 5.13, take #1 - Fix regression with irqbypass not restarting the guest on failed connect - Fix regression with debug register decoding resulting in overlapping access - Commit exception state on exit to usrspace - Fix the MMU notifier return values - Add missing 'static' qualifiers in the new host stage-2 code
Diffstat (limited to 'kernel/gcov/fs.c')
-rw-r--r--kernel/gcov/fs.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/kernel/gcov/fs.c b/kernel/gcov/fs.c
index 82babf5aa077..5c3086cad8f9 100644
--- a/kernel/gcov/fs.c
+++ b/kernel/gcov/fs.c
@@ -26,6 +26,7 @@
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/seq_file.h>
+#include <linux/mm.h>
#include "gcov.h"
/**
@@ -85,6 +86,115 @@ static int __init gcov_persist_setup(char *str)
}
__setup("gcov_persist=", gcov_persist_setup);
+#define ITER_STRIDE PAGE_SIZE
+
+/**
+ * struct gcov_iterator - specifies current file position in logical records
+ * @info: associated profiling data
+ * @buffer: buffer containing file data
+ * @size: size of buffer
+ * @pos: current position in file
+ */
+struct gcov_iterator {
+ struct gcov_info *info;
+ size_t size;
+ loff_t pos;
+ char buffer[];
+};
+
+/**
+ * gcov_iter_new - allocate and initialize profiling data iterator
+ * @info: profiling data set to be iterated
+ *
+ * Return file iterator on success, %NULL otherwise.
+ */
+static struct gcov_iterator *gcov_iter_new(struct gcov_info *info)
+{
+ struct gcov_iterator *iter;
+ size_t size;
+
+ /* Dry-run to get the actual buffer size. */
+ size = convert_to_gcda(NULL, info);
+
+ iter = kvmalloc(struct_size(iter, buffer, size), GFP_KERNEL);
+ if (!iter)
+ return NULL;
+
+ iter->info = info;
+ iter->size = size;
+ convert_to_gcda(iter->buffer, info);
+
+ return iter;
+}
+
+
+/**
+ * gcov_iter_free - free iterator data
+ * @iter: file iterator
+ */
+static void gcov_iter_free(struct gcov_iterator *iter)
+{
+ kvfree(iter);
+}
+
+/**
+ * gcov_iter_get_info - return profiling data set for given file iterator
+ * @iter: file iterator
+ */
+static struct gcov_info *gcov_iter_get_info(struct gcov_iterator *iter)
+{
+ return iter->info;
+}
+
+/**
+ * gcov_iter_start - reset file iterator to starting position
+ * @iter: file iterator
+ */
+static void gcov_iter_start(struct gcov_iterator *iter)
+{
+ iter->pos = 0;
+}
+
+/**
+ * gcov_iter_next - advance file iterator to next logical record
+ * @iter: file iterator
+ *
+ * Return zero if new position is valid, non-zero if iterator has reached end.
+ */
+static int gcov_iter_next(struct gcov_iterator *iter)
+{
+ if (iter->pos < iter->size)
+ iter->pos += ITER_STRIDE;
+
+ if (iter->pos >= iter->size)
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * gcov_iter_write - write data for current pos to seq_file
+ * @iter: file iterator
+ * @seq: seq_file handle
+ *
+ * Return zero on success, non-zero otherwise.
+ */
+static int gcov_iter_write(struct gcov_iterator *iter, struct seq_file *seq)
+{
+ size_t len;
+
+ if (iter->pos >= iter->size)
+ return -EINVAL;
+
+ len = ITER_STRIDE;
+ if (iter->pos + len > iter->size)
+ len = iter->size - iter->pos;
+
+ seq_write(seq, iter->buffer + iter->pos, len);
+
+ return 0;
+}
+
/*
* seq_file.start() implementation for gcov data files. Note that the
* gcov_iterator interface is designed to be more restrictive than seq_file