[S390] cio: Add chsc subchannel driver.

This patch adds a driver for subchannels of type chsc.

A device /dev/chsc is created which may be used to issue ioctls to:
- obtain information about the machine's I/O configuration
- dynamically change the machine's I/O configuration via
  asynchronous chsc commands

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

5 files changed, 163 insertions, 1 deletions

diff --git a/include/asm-s390/Kbuild b/include/asm-s390/Kbuild
index 13c9805349f1..09f312501eb5 100644
--- a/include/asm-s390/Kbuild
+++ b/include/asm-s390/Kbuild
@@ -8,6 +8,9 @@ header-y += ucontext.h
 header-y += vtoc.h
 header-y += zcrypt.h
 header-y += kvm.h
+header-y += schid.h
+header-y += chsc.h
 
 unifdef-y += cmb.h
 unifdef-y += debug.h
+unifdef-y += chpid.h
diff --git a/include/asm-s390/chpid.h b/include/asm-s390/chpid.h
index b203336fd892..606844d0a5c3 100644
--- a/include/asm-s390/chpid.h
+++ b/include/asm-s390/chpid.h
@@ -10,7 +10,6 @@
 
 #include <linux/string.h>
 #include <asm/types.h>
-#include <asm/cio.h>
 
 #define __MAX_CHPID 255
 
@@ -41,6 +40,9 @@ static inline void chp_id_next(struct chp_id *chpid)
         }
 }
 
+#ifdef __KERNEL__
+#include <asm/cio.h>
+
 static inline int chp_id_is_valid(struct chp_id *chpid)
 {
         return (chpid->cssid <= __MAX_CSSID);
@@ -49,5 +51,6 @@ static inline int chp_id_is_valid(struct chp_id *chpid)
 
 #define chp_id_for_each(c) \
         for (chp_id_init(c); chp_id_is_valid(c); chp_id_next(c))
+#endif /* __KERNEL */
 
 #endif /* _ASM_S390_CHPID_H */
diff --git a/include/asm-s390/chsc.h b/include/asm-s390/chsc.h
new file mode 100644
index 000000000000..d38d0cf62d4b
--- /dev/null
+++ b/include/asm-s390/chsc.h
@@ -0,0 +1,127 @@
+/*
+ * ioctl interface for /dev/chsc
+ *
+ * Copyright 2008 IBM Corp.
+ * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
+ */
+
+#ifndef _ASM_CHSC_H
+#define _ASM_CHSC_H
+
+#include <asm/chpid.h>
+#include <asm/schid.h>
+
+struct chsc_async_header {
+        __u16 length;
+        __u16 code;
+        __u32 cmd_dependend;
+        __u32 key : 4;
+        __u32 : 28;
+        struct subchannel_id sid;
+} __attribute__ ((packed));
+
+struct chsc_async_area {
+        struct chsc_async_header header;
+        __u8 data[PAGE_SIZE - 16 /* size of chsc_async_header */];
+} __attribute__ ((packed));
+
+
+struct chsc_response_struct {
+        __u16 length;
+        __u16 code;
+        __u32 parms;
+        __u8 data[PAGE_SIZE - 8];
+} __attribute__ ((packed));
+
+struct chsc_chp_cd {
+        struct chp_id chpid;
+        int m;
+        int fmt;
+        struct chsc_response_struct cpcb;
+};
+
+struct chsc_cu_cd {
+        __u16 cun;
+        __u8 cssid;
+        int m;
+        int fmt;
+        struct chsc_response_struct cucb;
+};
+
+struct chsc_sch_cud {
+        struct subchannel_id schid;
+        int fmt;
+        struct chsc_response_struct scub;
+};
+
+struct conf_id {
+        int m;
+        __u8 cssid;
+        __u8 ssid;
+};
+
+struct chsc_conf_info {
+        struct conf_id id;
+        int fmt;
+        struct chsc_response_struct scid;
+};
+
+struct ccl_parm_chpid {
+        int m;
+        struct chp_id chp;
+};
+
+struct ccl_parm_cssids {
+        __u8 f_cssid;
+        __u8 l_cssid;
+};
+
+struct chsc_comp_list {
+        struct {
+                enum {
+                        CCL_CU_ON_CHP = 1,
+                        CCL_CHP_TYPE_CAP = 2,
+                        CCL_CSS_IMG = 4,
+                        CCL_CSS_IMG_CONF_CHAR = 5,
+                        CCL_IOP_CHP = 6,
+                } ctype;
+                int fmt;
+                struct ccl_parm_chpid chpid;
+                struct ccl_parm_cssids cssids;
+        } req;
+        struct chsc_response_struct sccl;
+};
+
+struct chsc_dcal {
+        struct {
+                enum {
+                        DCAL_CSS_IID_PN = 4,
+                } atype;
+                __u32 list_parm[2];
+                int fmt;
+        } req;
+        struct chsc_response_struct sdcal;
+};
+
+struct chsc_cpd_info {
+        struct chp_id chpid;
+        int m;
+        int fmt;
+        int rfmt;
+        int c;
+        struct chsc_response_struct chpdb;
+};
+
+#define CHSC_IOCTL_MAGIC 'c'
+
+#define CHSC_START _IOWR(CHSC_IOCTL_MAGIC, 0x81, struct chsc_async_area)
+#define CHSC_INFO_CHANNEL_PATH _IOWR(CHSC_IOCTL_MAGIC, 0x82, \
+                                    struct chsc_chp_cd)
+#define CHSC_INFO_CU _IOWR(CHSC_IOCTL_MAGIC, 0x83, struct chsc_cu_cd)
+#define CHSC_INFO_SCH_CU _IOWR(CHSC_IOCTL_MAGIC, 0x84, struct chsc_sch_cud)
+#define CHSC_INFO_CI _IOWR(CHSC_IOCTL_MAGIC, 0x85, struct chsc_conf_info)
+#define CHSC_INFO_CCL _IOWR(CHSC_IOCTL_MAGIC, 0x86, struct chsc_comp_list)
+#define CHSC_INFO_CPD _IOWR(CHSC_IOCTL_MAGIC, 0x87, struct chsc_cpd_info)
+#define CHSC_INFO_DCAL _IOWR(CHSC_IOCTL_MAGIC, 0x88, struct chsc_dcal)
+
+#endif
diff --git a/include/asm-s390/isc.h b/include/asm-s390/isc.h
index fe56f7b445ea..34bb8916db4f 100644
--- a/include/asm-s390/isc.h
+++ b/include/asm-s390/isc.h
@@ -14,6 +14,7 @@
 /* Regular I/O interrupts. */
 #define IO_SCH_ISC 3                    /* regular I/O subchannels */
 #define CONSOLE_ISC 1                   /* console I/O subchannel */
+#define CHSC_SCH_ISC 7                  /* CHSC subchannels */
 /* Adapter interrupts. */
 #define QDIO_AIRQ_ISC IO_SCH_ISC        /* I/O subchannel in qdio mode */
 
diff --git a/include/asm-s390/schid.h b/include/asm-s390/schid.h
new file mode 100644
index 000000000000..5017ffa78e04
--- /dev/null
+++ b/include/asm-s390/schid.h
@@ -0,0 +1,28 @@
+#ifndef ASM_SCHID_H
+#define ASM_SCHID_H
+
+struct subchannel_id {
+        __u32 cssid : 8;
+        __u32 : 4;
+        __u32 m : 1;
+        __u32 ssid : 2;
+        __u32 one : 1;
+        __u32 sch_no : 16;
+} __attribute__ ((packed, aligned(4)));
+
+
+/* Helper function for sane state of pre-allocated subchannel_id. */
+static inline void
+init_subchannel_id(struct subchannel_id *schid)
+{
+        memset(schid, 0, sizeof(struct subchannel_id));
+        schid->one = 1;
+}
+
+static inline int
+schid_equal(struct subchannel_id *schid1, struct subchannel_id *schid2)
+{
+        return !memcmp(schid1, schid2, sizeof(struct subchannel_id));
+}
+
+#endif /* ASM_SCHID_H */