Merge tag 's390-6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull more s390 updates from Vasily Gorbik:

 - Clean up and improve vdso code: use SYM_* macros for function and
   data annotations, add CFI annotations to fix GDB unwinding, optimize
   the chacha20 implementation

 - Add vfio-ap driver feature advertisement for use by libvirt and
   mdevctl

* tag 's390-6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/vfio-ap: Driver feature advertisement
  s390/vdso: Use one large alternative instead of an alternative branch
  s390/vdso: Use SYM_DATA_START_LOCAL()/SYM_DATA_END() for data objects
  tools: Add additional SYM_*() stubs to linkage.h
  s390/vdso: Use macros for annotation of asm functions
  s390/vdso: Add CFI annotations to __arch_chacha20_blocks_nostack()
  s390/vdso: Fix comment within __arch_chacha20_blocks_nostack()
  s390/vdso: Get rid of permutation constants

Author: torvalds

Documentation/arch/s390/vfio-ap.rst

@@ -999,6 +999,36 @@ the vfio_ap mediated device to which it is assigned as long as each new APQN
 resulting from plugging it in references a queue device bound to the vfio_ap
 device driver.
 
+Driver Features
+===============
+The vfio_ap driver exposes a sysfs file containing supported features.
+This exists so third party tools (like Libvirt and mdevctl) can query the
+availability of specific features.
+
+The features list can be found here: /sys/bus/matrix/devices/matrix/features
+
+Entries are space delimited. Each entry consists of a combination of
+alphanumeric and underscore characters.
+
+Example:
+cat /sys/bus/matrix/devices/matrix/features
+guest_matrix dyn ap_config
+
+the following features are advertised:
+
+---------------+---------------------------------------------------------------+
+| Flag         | Description                                                   |
++==============+===============================================================+
+| guest_matrix | guest_matrix attribute exists. It reports the matrix of       |
+|              | adapters and domains that are or will be passed through to a  |
+|              | guest when the mdev is attached to it.                        |
++--------------+---------------------------------------------------------------+
+| dyn          | Indicates hot plug/unplug of AP adapters, domains and control |
+|              | domains for a guest to which the mdev is attached.            |
++------------+-----------------------------------------------------------------+
+| ap_config    | ap_config interface for one-shot modifications to mdev config |
++--------------+---------------------------------------------------------------+
+
 Limitations
 ===========
 Live guest migration is not supported for guests using AP devices without

arch/s390/kernel/vdso64/vdso_user_wrapper.S

@@ -13,10 +13,7 @@
  * for details.
  */
 .macro vdso_func func
-	.globl __kernel_\func
-	.type  __kernel_\func,@function
-	__ALIGN
-__kernel_\func:
+SYM_FUNC_START(__kernel_\func)
 	CFI_STARTPROC
 	aghi	%r15,-STACK_FRAME_VDSO_OVERHEAD
 	CFI_DEF_CFA_OFFSET (STACK_FRAME_USER_OVERHEAD + STACK_FRAME_VDSO_OVERHEAD)
@@ -32,7 +29,7 @@ __kernel_\func:
 	CFI_RESTORE 15
 	br	%r14
 	CFI_ENDPROC
-	.size	__kernel_\func,.-__kernel_\func
+SYM_FUNC_END(__kernel_\func)
 .endm
 
 vdso_func gettimeofday
@@ -41,16 +38,13 @@ vdso_func clock_gettime
 vdso_func getcpu
 
 .macro vdso_syscall func,syscall
-	.globl __kernel_\func
-	.type  __kernel_\func,@function
-	__ALIGN
-__kernel_\func:
+SYM_FUNC_START(__kernel_\func)
 	CFI_STARTPROC
 	svc	\syscall
 	/* Make sure we notice when a syscall returns, which shouldn't happen */
 	.word	0
 	CFI_ENDPROC
-	.size	__kernel_\func,.-__kernel_\func
+SYM_FUNC_END(__kernel_\func)
 .endm
 
 vdso_syscall restart_syscall,__NR_restart_syscall

arch/s390/kernel/vdso64/vgetrandom-chacha.S

@@ -1,7 +1,9 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 
+#include <linux/stringify.h>
 #include <linux/linkage.h>
 #include <asm/alternative.h>
+#include <asm/dwarf.h>
 #include <asm/fpu-insn.h>
 
 #define STATE0	%v0
@@ -12,9 +14,6 @@
 #define COPY1	%v5
 #define COPY2	%v6
 #define COPY3	%v7
-#define PERM4	%v16
-#define PERM8	%v17
-#define PERM12	%v18
 #define BEPERM	%v19
 #define TMP0	%v20
 #define TMP1	%v21
@@ -23,13 +22,11 @@
 
 	.section .rodata
 
-	.balign 128
-.Lconstants:
+	.balign 32
+SYM_DATA_START_LOCAL(chacha20_constants)
 	.long	0x61707865,0x3320646e,0x79622d32,0x6b206574 # endian-neutral
-	.long	0x04050607,0x08090a0b,0x0c0d0e0f,0x00010203 # rotl  4 bytes
-	.long	0x08090a0b,0x0c0d0e0f,0x00010203,0x04050607 # rotl  8 bytes
-	.long	0x0c0d0e0f,0x00010203,0x04050607,0x08090a0b # rotl 12 bytes
 	.long	0x03020100,0x07060504,0x0b0a0908,0x0f0e0d0c # byte swap
+SYM_DATA_END(chacha20_constants)
 
 	.text
 /*
@@ -43,13 +40,14 @@
  *				       size_t nblocks)
  */
 SYM_FUNC_START(__arch_chacha20_blocks_nostack)
-	larl	%r1,.Lconstants
+	CFI_STARTPROC
+	larl	%r1,chacha20_constants
 
 	/* COPY0 = "expand 32-byte k" */
 	VL	COPY0,0,,%r1
 
-	/* PERM4-PERM12,BEPERM = byte selectors for VPERM */
-	VLM	PERM4,BEPERM,16,%r1
+	/* BEPERM = byte selectors for VPERM */
+	ALTERNATIVE __stringify(VL BEPERM,16,,%r1), "brcl 0,0", ALT_FACILITY(148)
 
 	/* COPY1,COPY2 = key */
 	VLM	COPY1,COPY2,0,%r3
@@ -89,11 +87,11 @@ SYM_FUNC_START(__arch_chacha20_blocks_nostack)
 	VERLLF	STATE1,STATE1,7
 
 	/* STATE1[0,1,2,3] = STATE1[1,2,3,0] */
-	VPERM	STATE1,STATE1,STATE1,PERM4
+	VSLDB	STATE1,STATE1,STATE1,4
 	/* STATE2[0,1,2,3] = STATE2[2,3,0,1] */
-	VPERM	STATE2,STATE2,STATE2,PERM8
+	VSLDB	STATE2,STATE2,STATE2,8
 	/* STATE3[0,1,2,3] = STATE3[3,0,1,2] */
-	VPERM	STATE3,STATE3,STATE3,PERM12
+	VSLDB	STATE3,STATE3,STATE3,12
 
 	/* STATE0 += STATE1, STATE3 = rotl32(STATE3 ^ STATE0, 16) */
 	VAF	STATE0,STATE0,STATE1
@@ -116,32 +114,38 @@ SYM_FUNC_START(__arch_chacha20_blocks_nostack)
 	VERLLF	STATE1,STATE1,7
 
 	/* STATE1[0,1,2,3] = STATE1[3,0,1,2] */
-	VPERM	STATE1,STATE1,STATE1,PERM12
+	VSLDB	STATE1,STATE1,STATE1,12
 	/* STATE2[0,1,2,3] = STATE2[2,3,0,1] */
-	VPERM	STATE2,STATE2,STATE2,PERM8
+	VSLDB	STATE2,STATE2,STATE2,8
 	/* STATE3[0,1,2,3] = STATE3[1,2,3,0] */
-	VPERM	STATE3,STATE3,STATE3,PERM4
+	VSLDB	STATE3,STATE3,STATE3,4
 	brctg	%r0,.Ldoubleround
 
-	/* OUTPUT0 = STATE0 + STATE0 */
+	/* OUTPUT0 = STATE0 + COPY0 */
 	VAF	STATE0,STATE0,COPY0
-	/* OUTPUT1 = STATE1 + STATE1 */
+	/* OUTPUT1 = STATE1 + COPY1 */
 	VAF	STATE1,STATE1,COPY1
-	/* OUTPUT2 = STATE2 + STATE2 */
+	/* OUTPUT2 = STATE2 + COPY2 */
 	VAF	STATE2,STATE2,COPY2
-	/* OUTPUT2 = STATE3 + STATE3 */
+	/* OUTPUT3 = STATE3 + COPY3 */
 	VAF	STATE3,STATE3,COPY3
 
-	/*
-	 * 32 bit wise little endian store to OUTPUT. If the vector
-	 * enhancement facility 2 is not installed use the slow path.
-	 */
-	ALTERNATIVE "brc 0xf,.Lstoreslow", "nop", ALT_FACILITY(148)
-	VSTBRF	STATE0,0,,%r2
-	VSTBRF	STATE1,16,,%r2
-	VSTBRF	STATE2,32,,%r2
-	VSTBRF	STATE3,48,,%r2
-.Lstoredone:
+	ALTERNATIVE							\
+		__stringify(						\
+		/* Convert STATE to little endian and store to OUTPUT */\
+		VPERM	TMP0,STATE0,STATE0,BEPERM;			\
+		VPERM	TMP1,STATE1,STATE1,BEPERM;			\
+		VPERM	TMP2,STATE2,STATE2,BEPERM;			\
+		VPERM	TMP3,STATE3,STATE3,BEPERM;			\
+		VSTM	TMP0,TMP3,0,%r2),				\
+		__stringify(						\
+		/* 32 bit wise little endian store to OUTPUT */		\
+		VSTBRF	STATE0,0,,%r2;					\
+		VSTBRF	STATE1,16,,%r2;					\
+		VSTBRF	STATE2,32,,%r2;					\
+		VSTBRF	STATE3,48,,%r2;					\
+		brcl	0,0),						\
+		ALT_FACILITY(148)
 
 	/* ++COPY3.COUNTER */
 	/* alsih %r3,1 */
@@ -173,13 +177,5 @@ SYM_FUNC_START(__arch_chacha20_blocks_nostack)
 	VZERO	TMP3
 
 	br	%r14
-
-.Lstoreslow:
-	/* Convert STATE to little endian format and store to OUTPUT */
-	VPERM	TMP0,STATE0,STATE0,BEPERM
-	VPERM	TMP1,STATE1,STATE1,BEPERM
-	VPERM	TMP2,STATE2,STATE2,BEPERM
-	VPERM	TMP3,STATE3,STATE3,BEPERM
-	VSTM	TMP0,TMP3,0,%r2
-	j	.Lstoredone
+	CFI_ENDPROC
 SYM_FUNC_END(__arch_chacha20_blocks_nostack)

drivers/s390/crypto/vfio_ap_drv.c

@@ -26,6 +26,18 @@ MODULE_LICENSE("GPL v2");
 struct ap_matrix_dev *matrix_dev;
 debug_info_t *vfio_ap_dbf_info;
 
+static ssize_t features_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "guest_matrix hotplug ap_config\n");
+}
+static DEVICE_ATTR_RO(features);
+
+static struct attribute *matrix_dev_attrs[] = {
+	&dev_attr_features.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(matrix_dev);
+
 /* Only type 10 adapters (CEX4 and later) are supported
  * by the AP matrix device driver
  */
@@ -68,6 +80,7 @@ static struct device_driver matrix_driver = {
 	.name = "vfio_ap",
 	.bus = &matrix_bus,
 	.suppress_bind_attrs = true,
+	.dev_groups = matrix_dev_groups,
 };
 
 static int vfio_ap_matrix_dev_create(void)

tools/include/linux/linkage.h

@@ -4,7 +4,9 @@
 #include <linux/export.h>
 
 #define SYM_FUNC_START(x) .globl x; x:
-
 #define SYM_FUNC_END(x)
+#define SYM_DATA_START(x) .globl x; x:
+#define SYM_DATA_START_LOCAL(x) x:
+#define SYM_DATA_END(x)
 
 #endif /* _TOOLS_INCLUDE_LINUX_LINKAGE_H */