Merge tag 'qcom-drivers-for-6.7' of https://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux into soc/drivers

Qualcomm driver updates for v6.7

This introduces partial support for the Qualcomm Secure Execution
Environment SCM interface, and uses this to implement EFI variable
access on the Windows On Snapdragon devices (for now).

The 32/64-bit calling convention detector of the SCM interface is
updated to not choose 64-bit convention when Linux is 32-bit. The
"extern" specifier is dropped from the interface include file.

The LLCC driver gains support for carrying configuration for multiple
different system/DDR configurations for a given platform, and selecting
between them. Support for Q[DR]U1000 is added to the driver.

All exported symbols are transitioned to EXPORT_SYMBOL_GPL().

The platform_drivers in the Qualcomm SoC are transitioned to the
void-returning remove_new implementation.

The rmtfs memory driver gains support for leaving guard pages around the
used area, to avoid issues if the allocation happens to be placed
adjacent to another protected memory region.

The socinfo driver gains knowledge about IPQ8174, QCM6490, SM7150P and
various PMICs used together with SM8550.

* tag 'qcom-drivers-for-6.7' of https://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux: (44 commits)
  soc: qcom: socinfo: Convert to platform remove callback returning void
  soc: qcom: smsm: Convert to platform remove callback returning void
  soc: qcom: smp2p: Convert to platform remove callback returning void
  soc: qcom: smem: Convert to platform remove callback returning void
  soc: qcom: rmtfs_mem: Convert to platform remove callback returning void
  soc: qcom: qcom_stats: Convert to platform remove callback returning void
  soc: qcom: qcom_gsbi: Convert to platform remove callback returning void
  soc: qcom: qcom_aoss: Convert to platform remove callback returning void
  soc: qcom: pmic_glink: Convert to platform remove callback returning void
  soc: qcom: ocmem: Convert to platform remove callback returning void
  soc: qcom: llcc-qcom: Convert to platform remove callback returning void
  soc: qcom: icc-bwmon: Convert to platform remove callback returning void
  firmware: qcom_scm: use 64-bit calling convention only when client is 64-bit
  soc: qcom: llcc: Handle a second device without data corruption
  soc: qcom: Switch to EXPORT_SYMBOL_GPL()
  soc: qcom: smem: Annotate struct qcom_smem with __counted_by
  soc: qcom: rmtfs: Support discarding guard pages
  dt-bindings: reserved-memory: rmtfs: Allow guard pages
  dt-bindings: firmware: qcom,scm: document IPQ5018 compatible
  firmware: qcom_scm: disable SDI if required
  ...

Link: https://lore.kernel.org/r/20231015204014.855672-1-andersson@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 52 insertions, 0 deletions

diff --git a/lib/ucs2_string.c b/lib/ucs2_string.c
index 0a559a42359b8..9308bcfb2ad50 100644
--- a/lib/ucs2_string.c
+++ b/lib/ucs2_string.c
@@ -32,6 +32,58 @@ ucs2_strsize(const ucs2_char_t *data, unsigned long maxlength)
 }
 EXPORT_SYMBOL(ucs2_strsize);
 
+/**
+ * ucs2_strscpy() - Copy a UCS2 string into a sized buffer.
+ *
+ * @dst: Pointer to the destination buffer where to copy the string to.
+ * @src: Pointer to the source buffer where to copy the string from.
+ * @count: Size of the destination buffer, in UCS2 (16-bit) characters.
+ *
+ * Like strscpy(), only for UCS2 strings.
+ *
+ * Copy the source string @src, or as much of it as fits, into the destination
+ * buffer @dst. The behavior is undefined if the string buffers overlap. The
+ * destination buffer @dst is always NUL-terminated, unless it's zero-sized.
+ *
+ * Return: The number of characters copied into @dst (excluding the trailing
+ * %NUL terminator) or -E2BIG if @count is 0 or @src was truncated due to the
+ * destination buffer being too small.
+ */
+ssize_t ucs2_strscpy(ucs2_char_t *dst, const ucs2_char_t *src, size_t count)
+{
+	long res;
+
+	/*
+	 * Ensure that we have a valid amount of space. We need to store at
+	 * least one NUL-character.
+	 */
+	if (count == 0 || WARN_ON_ONCE(count > INT_MAX / sizeof(*dst)))
+		return -E2BIG;
+
+	/*
+	 * Copy at most 'count' characters, return early if we find a
+	 * NUL-terminator.
+	 */
+	for (res = 0; res < count; res++) {
+		ucs2_char_t c;
+
+		c = src[res];
+		dst[res] = c;
+
+		if (!c)
+			return res;
+	}
+
+	/*
+	 * The loop above terminated without finding a NUL-terminator,
+	 * exceeding the 'count': Enforce proper NUL-termination and return
+	 * error.
+	 */
+	dst[count - 1] = 0;
+	return -E2BIG;
+}
+EXPORT_SYMBOL(ucs2_strscpy);
+
 int
 ucs2_strncmp(const ucs2_char_t *a, const ucs2_char_t *b, size_t len)
 {