ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted

make htmldocs fails with:

  Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301:
  ERROR: Unexpected indentation. [docutils]

The Return: section of ata_dsm_trim_pages() ends its first sentence with
a colon and continues with an indented bullet list. reStructuredText
requires a blank line before an indented block, so docutils chokes on
the list.

Simply adding the missing blank line does not work either: Return: is a
kernel-doc "special section", which is terminated by the first blank
line, so the bullet list would end up in the Description section,
detached from the sentence introducing it.

Spell the two bounds out as prose instead, so that the Return: section
stays self-contained. Documentation-only change.

Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND")
Reported-by: Thomas Huth <thuth@redhat.com>
Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>

1 files changed, 95 insertions, 0 deletions

diff --git a/lib/argv_split.c b/lib/argv_split.c
new file mode 100644
index 000000000..e28db8e3b
--- /dev/null
+++ b/lib/argv_split.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Helper function for splitting a string into an argv-like array.
+ */
+
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+static int count_argc(const char *str)
+{
+	int count = 0;
+	bool was_space;
+
+	for (was_space = true; *str; str++) {
+		if (isspace(*str)) {
+			was_space = true;
+		} else if (was_space) {
+			was_space = false;
+			count++;
+		}
+	}
+
+	return count;
+}
+
+/**
+ * argv_free - free an argv
+ * @argv: the argument vector to be freed
+ *
+ * Frees an argv and the strings it points to.
+ */
+void argv_free(char **argv)
+{
+	argv--;
+	kfree(argv[0]);
+	kfree(argv);
+}
+EXPORT_SYMBOL(argv_free);
+
+/**
+ * argv_split - split a string at whitespace, returning an argv
+ * @gfp: the GFP mask used to allocate memory
+ * @str: the string to be split
+ * @argcp: returned argument count
+ *
+ * Returns: an array of pointers to strings which are split out from
+ * @str.  This is performed by strictly splitting on white-space; no
+ * quote processing is performed.  Multiple whitespace characters are
+ * considered to be a single argument separator.  The returned array
+ * is always NULL-terminated.  Returns NULL on memory allocation
+ * failure.
+ *
+ * The source string at `str' may be undergoing concurrent alteration via
+ * userspace sysctl activity (at least).  The argv_split() implementation
+ * attempts to handle this gracefully by taking a local copy to work on.
+ */
+char **argv_split(gfp_t gfp, const char *str, int *argcp)
+{
+	char *argv_str;
+	bool was_space;
+	char **argv, **argv_ret;
+	int argc;
+
+	argv_str = kstrndup(str, KMALLOC_MAX_SIZE - 1, gfp);
+	if (!argv_str)
+		return NULL;
+
+	argc = count_argc(argv_str);
+	argv = kmalloc_array(argc + 2, sizeof(*argv), gfp);
+	if (!argv) {
+		kfree(argv_str);
+		return NULL;
+	}
+
+	*argv = argv_str;
+	argv_ret = ++argv;
+	for (was_space = true; *argv_str; argv_str++) {
+		if (isspace(*argv_str)) {
+			was_space = true;
+			*argv_str = 0;
+		} else if (was_space) {
+			was_space = false;
+			*argv++ = argv_str;
+		}
+	}
+	*argv = NULL;
+
+	if (argcp)
+		*argcp = argc;
+	return argv_ret;
+}
+EXPORT_SYMBOL(argv_split);