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, 260 insertions, 0 deletions

diff --git a/scripts/cleanpatch b/scripts/cleanpatch
new file mode 100755
index 000000000..9f1755271
--- /dev/null
+++ b/scripts/cleanpatch
@@ -0,0 +1,260 @@
+#!/usr/bin/env perl
+# SPDX-License-Identifier: GPL-2.0
+#
+# Clean a patch file -- or directory of patch files -- of stealth whitespace.
+# WARNING: this can be a highly destructive operation.  Use with caution.
+#
+
+use warnings;
+use bytes;
+use File::Basename;
+
+# Default options
+$max_width = 79;
+
+# Clean up space-tab sequences, either by removing spaces or
+# replacing them with tabs.
+sub clean_space_tabs($)
+{
+    no bytes;			# Tab alignment depends on characters
+
+    my($li) = @_;
+    my($lo) = '';
+    my $pos = 0;
+    my $nsp = 0;
+    my($i, $c);
+
+    for ($i = 0; $i < length($li); $i++) {
+	$c = substr($li, $i, 1);
+	if ($c eq "\t") {
+	    my $npos = ($pos+$nsp+8) & ~7;
+	    my $ntab = ($npos >> 3) - ($pos >> 3);
+	    $lo .= "\t" x $ntab;
+	    $pos = $npos;
+	    $nsp = 0;
+	} elsif ($c eq "\n" || $c eq "\r") {
+	    $lo .= " " x $nsp;
+	    $pos += $nsp;
+	    $nsp = 0;
+	    $lo .= $c;
+	    $pos = 0;
+	} elsif ($c eq " ") {
+	    $nsp++;
+	} else {
+	    $lo .= " " x $nsp;
+	    $pos += $nsp;
+	    $nsp = 0;
+	    $lo .= $c;
+	    $pos++;
+	}
+    }
+    $lo .= " " x $nsp;
+    return $lo;
+}
+
+# Compute the visual width of a string
+sub strwidth($) {
+    no bytes;			# Tab alignment depends on characters
+
+    my($li) = @_;
+    my($c, $i);
+    my $pos = 0;
+    my $mlen = 0;
+
+    for ($i = 0; $i < length($li); $i++) {
+	$c = substr($li,$i,1);
+	if ($c eq "\t") {
+	    $pos = ($pos+8) & ~7;
+	} elsif ($c eq "\n") {
+	    $mlen = $pos if ($pos > $mlen);
+	    $pos = 0;
+	} else {
+	    $pos++;
+	}
+    }
+
+    $mlen = $pos if ($pos > $mlen);
+    return $mlen;
+}
+
+$name = basename($0);
+
+@files = ();
+
+while (defined($a = shift(@ARGV))) {
+    if ($a =~ /^-/) {
+	if ($a eq '-width' || $a eq '-w') {
+	    $max_width = shift(@ARGV)+0;
+	} else {
+	    print STDERR "Usage: $name [-width #] files...\n";
+	    exit 1;
+	}
+    } else {
+	push(@files, $a);
+    }
+}
+
+foreach $f ( @files ) {
+    print STDERR "$name: $f\n";
+
+    if (! -f $f) {
+	print STDERR "$f: not a file\n";
+	next;
+    }
+
+    if (!open(FILE, '+<', $f)) {
+	print STDERR "$name: Cannot open file: $f: $!\n";
+	next;
+    }
+
+    binmode FILE;
+
+    # First, verify that it is not a binary file; consider any file
+    # with a zero byte to be a binary file.  Is there any better, or
+    # additional, heuristic that should be applied?
+    $is_binary = 0;
+
+    while (read(FILE, $data, 65536) > 0) {
+	if ($data =~ /\0/) {
+	    $is_binary = 1;
+	    last;
+	}
+    }
+
+    if ($is_binary) {
+	print STDERR "$name: $f: binary file\n";
+	next;
+    }
+
+    seek(FILE, 0, 0);
+
+    $in_bytes = 0;
+    $out_bytes = 0;
+    $lineno = 0;
+
+    @lines  = ();
+
+    $in_hunk = 0;
+    $err = 0;
+
+    while ( defined($line = <FILE>) ) {
+	$lineno++;
+	$in_bytes += length($line);
+
+	if (!$in_hunk) {
+	    if ($line =~
+		/^\@\@\s+\-([0-9]+),([0-9]+)\s+\+([0-9]+),([0-9]+)\s\@\@/) {
+		$minus_lines = $2;
+		$plus_lines = $4;
+		if ($minus_lines || $plus_lines) {
+		    $in_hunk = 1;
+		    @hunk_lines = ($line);
+		}
+	    } else {
+		push(@lines, $line);
+		$out_bytes += length($line);
+	    }
+	} else {
+	    # We're in a hunk
+
+	    if ($line =~ /^\+/) {
+		$plus_lines--;
+
+		$text = substr($line, 1);
+		$text =~ s/[ \t\r]*$//;		# Remove trailing spaces
+		$text = clean_space_tabs($text);
+
+		$l_width = strwidth($text);
+		if ($max_width && $l_width > $max_width) {
+		    print STDERR
+			"$f:$lineno: adds line exceeds $max_width ",
+			"characters ($l_width)\n";
+		}
+
+		push(@hunk_lines, '+'.$text);
+	    } elsif ($line =~ /^\-/) {
+		$minus_lines--;
+		push(@hunk_lines, $line);
+	    } elsif ($line =~ /^ /) {
+		$plus_lines--;
+		$minus_lines--;
+		push(@hunk_lines, $line);
+	    } else {
+		print STDERR "$name: $f: malformed patch\n";
+		$err = 1;
+		last;
+	    }
+
+	    if ($plus_lines < 0 || $minus_lines < 0) {
+		print STDERR "$name: $f: malformed patch\n";
+		$err = 1;
+		last;
+	    } elsif ($plus_lines == 0 && $minus_lines == 0) {
+		# End of a hunk.  Process this hunk.
+		my $i;
+		my $l;
+		my @h = ();
+		my $adj = 0;
+		my $done = 0;
+
+		for ($i = scalar(@hunk_lines)-1; $i > 0; $i--) {
+		    $l = $hunk_lines[$i];
+		    if (!$done && $l eq "+\n") {
+			$adj++; # Skip this line
+		    } elsif ($l =~ /^[ +]/) {
+			$done = 1;
+			unshift(@h, $l);
+		    } else {
+			unshift(@h, $l);
+		    }
+		}
+
+		$l = $hunk_lines[0];  # Hunk header
+		undef @hunk_lines;    # Free memory
+
+		if ($adj) {
+		    die unless
+			($l =~ /^\@\@\s+\-([0-9]+),([0-9]+)\s+\+([0-9]+),([0-9]+)\s\@\@(.*)$/);
+		    my $mstart = $1;
+		    my $mlin = $2;
+		    my $pstart = $3;
+		    my $plin = $4;
+		    my $tail = $5; # doesn't include the final newline
+
+		    $l = sprintf("@@ -%d,%d +%d,%d @@%s\n",
+				 $mstart, $mlin, $pstart, $plin-$adj,
+				 $tail);
+		}
+		unshift(@h, $l);
+
+		# Transfer to the output array
+		foreach $l (@h) {
+		    $out_bytes += length($l);
+		    push(@lines, $l);
+		}
+
+		$in_hunk = 0;
+	    }
+	}
+    }
+
+    if ($in_hunk) {
+	print STDERR "$name: $f: malformed patch\n";
+	$err = 1;
+    }
+
+    if (!$err) {
+	if ($in_bytes != $out_bytes) {
+	    # Only write to the file if changed
+	    seek(FILE, 0, 0);
+	    print FILE @lines;
+
+	    if ( !defined($where = tell(FILE)) ||
+		 !truncate(FILE, $where) ) {
+		die "$name: Failed to truncate modified file: $f: $!\n";
+	    }
+	}
+    }
+
+    close(FILE);
+}