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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /fs/cachefiles/key.c
downloadlinux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz
linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
Diffstat (limited to 'fs/cachefiles/key.c')
-rw-r--r--fs/cachefiles/key.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/fs/cachefiles/key.c b/fs/cachefiles/key.c
new file mode 100644
index 000000000..aae86af48
--- /dev/null
+++ b/fs/cachefiles/key.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Key to pathname encoder
+ *
+ * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <linux/slab.h>
+#include "internal.h"
+
+static const char cachefiles_charmap[64] __nonstring =
+ "0123456789" /* 0 - 9 */
+ "abcdefghijklmnopqrstuvwxyz" /* 10 - 35 */
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZ" /* 36 - 61 */
+ "_-" /* 62 - 63 */
+ ;
+
+static const char cachefiles_filecharmap[256] = {
+ /* we skip space and tab and control chars */
+ [33 ... 46] = 1, /* '!' -> '.' */
+ /* we skip '/' as it's significant to pathwalk */
+ [48 ... 127] = 1, /* '0' -> '~' */
+};
+
+static inline unsigned int how_many_hex_digits(unsigned int x)
+{
+ return x ? round_up(ilog2(x) + 1, 4) / 4 : 0;
+}
+
+/*
+ * turn the raw key into something cooked
+ * - the key may be up to NAME_MAX in length (including the length word)
+ * - "base64" encode the strange keys, mapping 3 bytes of raw to four of
+ * cooked
+ * - need to cut the cooked key into 252 char lengths (189 raw bytes)
+ */
+bool cachefiles_cook_key(struct cachefiles_object *object)
+{
+ const u8 *key = fscache_get_key(object->cookie), *kend;
+ unsigned char ch;
+ unsigned int acc, i, n, nle, nbe, keylen = object->cookie->key_len;
+ unsigned int b64len, len, print, pad;
+ char *name, sep;
+
+ _enter(",%u,%*phN", keylen, keylen, key);
+
+ BUG_ON(keylen > NAME_MAX - 3);
+
+ print = 1;
+ for (i = 0; i < keylen; i++) {
+ ch = key[i];
+ print &= cachefiles_filecharmap[ch];
+ }
+
+ /* If the path is usable ASCII, then we render it directly */
+ if (print) {
+ len = 1 + keylen;
+ name = kmalloc(len + 1, GFP_KERNEL);
+ if (!name)
+ return false;
+
+ name[0] = 'D'; /* Data object type, string encoding */
+ memcpy(name + 1, key, keylen);
+ goto success;
+ }
+
+ /* See if it makes sense to encode it as "hex,hex,hex" for each 32-bit
+ * chunk. We rely on the key having been padded out to a whole number
+ * of 32-bit words.
+ */
+ n = round_up(keylen, 4);
+ nbe = nle = 0;
+ for (i = 0; i < n; i += 4) {
+ u32 be = be32_to_cpu(*(__be32 *)(key + i));
+ u32 le = le32_to_cpu(*(__le32 *)(key + i));
+
+ nbe += 1 + how_many_hex_digits(be);
+ nle += 1 + how_many_hex_digits(le);
+ }
+
+ b64len = DIV_ROUND_UP(keylen, 3);
+ pad = b64len * 3 - keylen;
+ b64len = 2 + b64len * 4; /* Length if we base64-encode it */
+ _debug("len=%u nbe=%u nle=%u b64=%u", keylen, nbe, nle, b64len);
+ if (nbe < b64len || nle < b64len) {
+ unsigned int nlen = min(nbe, nle) + 1;
+ name = kmalloc(nlen, GFP_KERNEL);
+ if (!name)
+ return false;
+ sep = (nbe <= nle) ? 'S' : 'T'; /* Encoding indicator */
+ len = 0;
+ for (i = 0; i < n; i += 4) {
+ u32 x;
+ if (nbe <= nle)
+ x = be32_to_cpu(*(__be32 *)(key + i));
+ else
+ x = le32_to_cpu(*(__le32 *)(key + i));
+ name[len++] = sep;
+ if (x != 0)
+ len += snprintf(name + len, nlen - len, "%x", x);
+ sep = ',';
+ }
+ goto success;
+ }
+
+ /* We need to base64-encode it */
+ name = kmalloc(b64len + 1, GFP_KERNEL);
+ if (!name)
+ return false;
+
+ name[0] = 'E';
+ name[1] = '0' + pad;
+ len = 2;
+ kend = key + keylen;
+ do {
+ acc = *key++;
+ if (key < kend) {
+ acc |= *key++ << 8;
+ if (key < kend)
+ acc |= *key++ << 16;
+ }
+
+ name[len++] = cachefiles_charmap[acc & 63];
+ acc >>= 6;
+ name[len++] = cachefiles_charmap[acc & 63];
+ acc >>= 6;
+ name[len++] = cachefiles_charmap[acc & 63];
+ acc >>= 6;
+ name[len++] = cachefiles_charmap[acc & 63];
+ } while (key < kend);
+
+success:
+ name[len] = 0;
+ object->d_name = name;
+ _leave(" = %s", object->d_name);
+ return true;
+}