KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted

Skip the xarray reservation loop when clearing all memory attributes, as
storing NULL only erases the entry and never needs to allocate, so no
reservation (and no cleanup of a failed one) is required in that case.

Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/include/sound/ak4531_codec.h b/include/sound/ak4531_codec.h
new file mode 100644
index 000000000..64402347d
--- /dev/null
+++ b/include/sound/ak4531_codec.h
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __SOUND_AK4531_CODEC_H
+#define __SOUND_AK4531_CODEC_H
+
+/*
+ *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
+ *  Universal interface for Audio Codec '97
+ *
+ *  For more details look to AC '97 component specification revision 2.1
+ *  by Intel Corporation (http://developer.intel.com).
+ */
+
+#include <sound/info.h>
+#include <sound/control.h>
+
+/*
+ *  ASAHI KASEI - AK4531 codec
+ *  - not really AC'97 codec, but it uses very similar interface as AC'97
+ */
+
+/*
+ *  AK4531 codec registers
+ */
+
+#define AK4531_LMASTER  0x00	/* master volume left */
+#define AK4531_RMASTER  0x01	/* master volume right */
+#define AK4531_LVOICE   0x02	/* channel volume left */
+#define AK4531_RVOICE   0x03	/* channel volume right */
+#define AK4531_LFM      0x04	/* FM volume left */
+#define AK4531_RFM      0x05	/* FM volume right */
+#define AK4531_LCD      0x06	/* CD volume left */
+#define AK4531_RCD      0x07	/* CD volume right */
+#define AK4531_LLINE    0x08	/* LINE volume left */
+#define AK4531_RLINE    0x09	/* LINE volume right */
+#define AK4531_LAUXA    0x0a	/* AUXA volume left */
+#define AK4531_RAUXA    0x0b	/* AUXA volume right */
+#define AK4531_MONO1    0x0c	/* MONO1 volume left */
+#define AK4531_MONO2    0x0d	/* MONO1 volume right */
+#define AK4531_MIC      0x0e	/* MIC volume */
+#define AK4531_MONO_OUT 0x0f	/* Mono-out volume */
+#define AK4531_OUT_SW1  0x10	/* Output mixer switch 1 */
+#define AK4531_OUT_SW2  0x11	/* Output mixer switch 2 */
+#define AK4531_LIN_SW1  0x12	/* Input left mixer switch 1 */
+#define AK4531_RIN_SW1  0x13	/* Input right mixer switch 1 */
+#define AK4531_LIN_SW2  0x14	/* Input left mixer switch 2 */
+#define AK4531_RIN_SW2  0x15	/* Input right mixer switch 2 */
+#define AK4531_RESET    0x16	/* Reset & power down */
+#define AK4531_CLOCK    0x17	/* Clock select */
+#define AK4531_AD_IN    0x18	/* AD input select */
+#define AK4531_MIC_GAIN 0x19	/* MIC amplified gain */
+
+struct snd_ak4531 {
+	void (*write) (struct snd_ak4531 *ak4531, unsigned short reg,
+		       unsigned short val);
+	void *private_data;
+	void (*private_free) (struct snd_ak4531 *ak4531);
+	/* --- */
+	unsigned char regs[0x20];
+	struct mutex reg_mutex;
+};
+
+int snd_ak4531_mixer(struct snd_card *card, struct snd_ak4531 *_ak4531,
+		     struct snd_ak4531 **rak4531);
+
+#ifdef CONFIG_PM
+void snd_ak4531_suspend(struct snd_ak4531 *ak4531);
+void snd_ak4531_resume(struct snd_ak4531 *ak4531);
+#else
+static inline void snd_ak4531_suspend(struct snd_ak4531 *ak4531) {}
+static inline void snd_ak4531_resume(struct snd_ak4531 *ak4531) {}
+#endif
+
+#endif /* __SOUND_AK4531_CODEC_H */