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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /fs/ntfs3/bitfunc.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
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>
Diffstat (limited to 'fs/ntfs3/bitfunc.c')
-rw-r--r--fs/ntfs3/bitfunc.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/fs/ntfs3/bitfunc.c b/fs/ntfs3/bitfunc.c
new file mode 100644
index 000000000..25a4d4896
--- /dev/null
+++ b/fs/ntfs3/bitfunc.c
@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *
+ * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
+ *
+ */
+
+#include <linux/types.h>
+
+#include "ntfs_fs.h"
+
+#define BITS_IN_SIZE_T (sizeof(size_t) * 8)
+
+/*
+ * fill_mask[i] - first i bits are '1' , i = 0,1,2,3,4,5,6,7,8
+ * fill_mask[i] = 0xFF >> (8-i)
+ */
+static const u8 fill_mask[] = { 0x00, 0x01, 0x03, 0x07, 0x0F,
+ 0x1F, 0x3F, 0x7F, 0xFF };
+
+/*
+ * zero_mask[i] - first i bits are '0' , i = 0,1,2,3,4,5,6,7,8
+ * zero_mask[i] = 0xFF << i
+ */
+static const u8 zero_mask[] = { 0xFF, 0xFE, 0xFC, 0xF8, 0xF0,
+ 0xE0, 0xC0, 0x80, 0x00 };
+
+/*
+ * are_bits_clear
+ *
+ * Return: True if all bits [bit, bit+nbits) are zeros "0".
+ */
+bool are_bits_clear(const void *lmap, size_t bit, size_t nbits)
+{
+ size_t pos = bit & 7;
+ const u8 *map = (u8 *)lmap + (bit >> 3);
+
+ if (pos) {
+ if (8 - pos >= nbits)
+ return !nbits || !(*map & fill_mask[pos + nbits] &
+ zero_mask[pos]);
+
+ if (*map++ & zero_mask[pos])
+ return false;
+ nbits -= 8 - pos;
+ }
+
+ pos = ((size_t)map) & (sizeof(size_t) - 1);
+ if (pos) {
+ pos = sizeof(size_t) - pos;
+ if (nbits >= pos * 8) {
+ for (nbits -= pos * 8; pos; pos--, map++) {
+ if (*map)
+ return false;
+ }
+ }
+ }
+
+ for (pos = nbits / BITS_IN_SIZE_T; pos; pos--, map += sizeof(size_t)) {
+ if (*((size_t *)map))
+ return false;
+ }
+
+ for (pos = (nbits % BITS_IN_SIZE_T) >> 3; pos; pos--, map++) {
+ if (*map)
+ return false;
+ }
+
+ pos = nbits & 7;
+ if (pos && (*map & fill_mask[pos]))
+ return false;
+
+ return true;
+}
+
+/*
+ * are_bits_set
+ *
+ * Return: True if all bits [bit, bit+nbits) are ones "1".
+ */
+bool are_bits_set(const void *lmap, size_t bit, size_t nbits)
+{
+ u8 mask;
+ size_t pos = bit & 7;
+ const u8 *map = (u8 *)lmap + (bit >> 3);
+
+ if (pos) {
+ if (8 - pos >= nbits) {
+ mask = fill_mask[pos + nbits] & zero_mask[pos];
+ return !nbits || (*map & mask) == mask;
+ }
+
+ mask = zero_mask[pos];
+ if ((*map++ & mask) != mask)
+ return false;
+ nbits -= 8 - pos;
+ }
+
+ pos = ((size_t)map) & (sizeof(size_t) - 1);
+ if (pos) {
+ pos = sizeof(size_t) - pos;
+ if (nbits >= pos * 8) {
+ for (nbits -= pos * 8; pos; pos--, map++) {
+ if (*map != 0xFF)
+ return false;
+ }
+ }
+ }
+
+ for (pos = nbits / BITS_IN_SIZE_T; pos; pos--, map += sizeof(size_t)) {
+ if (*((size_t *)map) != MINUS_ONE_T)
+ return false;
+ }
+
+ for (pos = (nbits % BITS_IN_SIZE_T) >> 3; pos; pos--, map++) {
+ if (*map != 0xFF)
+ return false;
+ }
+
+ pos = nbits & 7;
+ if (pos) {
+ mask = fill_mask[pos];
+ if ((*map & mask) != mask)
+ return false;
+ }
+
+ return true;
+}