s390/sysinfo,stsi: change return code handling

Change return code handling of the stsi() function:

In case function code 0 was specified the return value is the
current configuration level (already shifted). That way all
the code that actually copied the stsi_0() function can go
away.

Otherwise the return value is 0 (success) or negative to
indicate an error (currently only -EOPNOTSUPP).

Also stsi() is no longer an inline function. The function is
not performance critical, but every caller would generate an
exception table entry for this function.

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

diff --git a/arch/s390/include/asm/sysinfo.h b/arch/s390/include/asm/sysinfo.h
index 04e6e97..f92428e 100644 (file)
--- a/arch/s390/include/asm/sysinfo.h
+++ b/arch/s390/include/asm/sysinfo.h
@@ -153,21 +153,7 @@ struct sysinfo_15_1_x {
        union topology_entry tle[0];
 };
 
-static inline int stsi(void *sysinfo, int fc, int sel1, int sel2)
-{
-       register int r0 asm("0") = (fc << 28) | sel1;
-       register int r1 asm("1") = sel2;
-
-       asm volatile(
-               "   stsi 0(%2)\n"
-               "0: jz   2f\n"
-               "1: lhi  %0,%3\n"
-               "2:\n"
-               EX_TABLE(0b, 1b)
-               : "+d" (r0) : "d" (r1), "a" (sysinfo), "K" (-ENOSYS)
-               : "cc", "memory");
-       return r0;
-}
+int stsi(void *sysinfo, int fc, int sel1, int sel2);
 
 /*
  * Service level reporting interface.

diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index e8000d5..7f47176 100644 (file)
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -222,12 +222,12 @@ static noinline __init void detect_machine_type(void)
        struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page;
 
        /* Check current-configuration-level */
-       if ((stsi(NULL, 0, 0, 0) >> 28) <= 2) {
+       if (stsi(NULL, 0, 0, 0) <= 2) {
                S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
                return;
        }
        /* Get virtual-machine cpu information. */
-       if (stsi(vmms, 3, 2, 2) == -ENOSYS || !vmms->count)
+       if (stsi(vmms, 3, 2, 2) || !vmms->count)
                return;
 
        /* Running under KVM? If not we assume z/VM */
@@ -246,7 +246,7 @@ static __init void setup_topology(void)
                return;
        S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
        for (max_mnest = 6; max_mnest > 1; max_mnest--) {
-               if (stsi(&sysinfo_page, 15, 1, max_mnest) != -ENOSYS)
+               if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0)
                        break;
        }
        topology_max_mnest = max_mnest;

diff --git a/arch/s390/kernel/lgr.c b/arch/s390/kernel/lgr.c
index eca94e7..6ea6d69 100644 (file)
--- a/arch/s390/kernel/lgr.c
+++ b/arch/s390/kernel/lgr.c
@@ -51,16 +51,6 @@ static struct lgr_info lgr_info_cur;
 static struct debug_info *lgr_dbf;
 
 /*
- * Return number of valid stsi levels
- */
-static inline int stsi_0(void)
-{
-       int rc = stsi(NULL, 0, 0, 0);
-
-       return rc == -ENOSYS ? rc : (((unsigned int) rc) >> 28);
-}
-
-/*
  * Copy buffer and then convert it to ASCII
  */
 static void cpascii(char *dst, char *src, int size)
@@ -76,7 +66,7 @@ static void lgr_stsi_1_1_1(struct lgr_info *lgr_info)
 {
        struct sysinfo_1_1_1 *si = (void *) lgr_page;
 
-       if (stsi(si, 1, 1, 1) == -ENOSYS)
+       if (stsi(si, 1, 1, 1))
                return;
        cpascii(lgr_info->manufacturer, si->manufacturer,
                sizeof(si->manufacturer));
@@ -93,7 +83,7 @@ static void lgr_stsi_2_2_2(struct lgr_info *lgr_info)
 {
        struct sysinfo_2_2_2 *si = (void *) lgr_page;
 
-       if (stsi(si, 2, 2, 2) == -ENOSYS)
+       if (stsi(si, 2, 2, 2))
                return;
        cpascii(lgr_info->name, si->name, sizeof(si->name));
        memcpy(&lgr_info->lpar_number, &si->lpar_number,
@@ -108,7 +98,7 @@ static void lgr_stsi_3_2_2(struct lgr_info *lgr_info)
        struct sysinfo_3_2_2 *si = (void *) lgr_page;
        int i;
 
-       if (stsi(si, 3, 2, 2) == -ENOSYS)
+       if (stsi(si, 3, 2, 2))
                return;
        for (i = 0; i < min_t(u8, si->count, VM_LEVEL_MAX); i++) {
                cpascii(lgr_info->vm[i].name, si->vm[i].name,
@@ -124,16 +114,17 @@ static void lgr_stsi_3_2_2(struct lgr_info *lgr_info)
  */
 static void lgr_info_get(struct lgr_info *lgr_info)
 {
+       int level;
+
        memset(lgr_info, 0, sizeof(*lgr_info));
        stfle(lgr_info->stfle_fac_list, ARRAY_SIZE(lgr_info->stfle_fac_list));
-       lgr_info->level = stsi_0();
-       if (lgr_info->level == -ENOSYS)
-               return;
-       if (lgr_info->level >= 1)
+       level = stsi(NULL, 0, 0, 0);
+       lgr_info->level = level;
+       if (level >= 1)
                lgr_stsi_1_1_1(lgr_info);
-       if (lgr_info->level >= 2)
+       if (level >= 2)
                lgr_stsi_2_2_2(lgr_info);
-       if (lgr_info->level >= 3)
+       if (level >= 3)
                lgr_stsi_3_2_2(lgr_info);
 }
 

diff --git a/arch/s390/kernel/sysinfo.c b/arch/s390/kernel/sysinfo.c
index 2af4ee6..62f89d9 100644 (file)
--- a/arch/s390/kernel/sysinfo.c
+++ b/arch/s390/kernel/sysinfo.c
@@ -24,18 +24,38 @@
 
 int topology_max_mnest;
 
-static inline int stsi_0(void)
+/*
+ * stsi - store system information
+ *
+ * Returns the current configuration level if function code 0 was specified.
+ * Otherwise returns 0 on success or a negative value on error.
+ */
+int stsi(void *sysinfo, int fc, int sel1, int sel2)
 {
-       int rc = stsi(NULL, 0, 0, 0);
-
-       return rc == -ENOSYS ? rc : (((unsigned int) rc) >> 28);
+       register int r0 asm("0") = (fc << 28) | sel1;
+       register int r1 asm("1") = sel2;
+       int rc = 0;
+
+       asm volatile(
+               "       stsi    0(%3)\n"
+               "0:     jz      2f\n"
+               "1:     lhi     %1,%4\n"
+               "2:\n"
+               EX_TABLE(0b, 1b)
+               : "+d" (r0), "+d" (rc)
+               : "d" (r1), "a" (sysinfo), "K" (-EOPNOTSUPP)
+               : "cc", "memory");
+       if (rc)
+               return rc;
+       return fc ? 0 : ((unsigned int) r0) >> 28;
 }
+EXPORT_SYMBOL(stsi);
 
 static void stsi_1_1_1(struct seq_file *m, struct sysinfo_1_1_1 *info)
 {
        int i;
 
-       if (stsi(info, 1, 1, 1) == -ENOSYS)
+       if (stsi(info, 1, 1, 1))
                return;
        EBCASC(info->manufacturer, sizeof(info->manufacturer));
        EBCASC(info->type, sizeof(info->type));
@@ -97,7 +117,8 @@ static void stsi_15_1_x(struct seq_file *m, struct sysinfo_15_1_x *info)
        seq_putc(m, '\n');
        if (!MACHINE_HAS_TOPOLOGY)
                return;
-       stsi(info, 15, 1, topology_max_mnest);
+       if (stsi(info, 15, 1, topology_max_mnest))
+               return;
        seq_printf(m, "CPU Topology HW:     ");
        for (i = 0; i < TOPOLOGY_NR_MAG; i++)
                seq_printf(m, " %d", info->mag[i]);
@@ -116,7 +137,7 @@ static void stsi_1_2_2(struct seq_file *m, struct sysinfo_1_2_2 *info)
        struct sysinfo_1_2_2_extension *ext;
        int i;
 
-       if (stsi(info, 1, 2, 2) == -ENOSYS)
+       if (stsi(info, 1, 2, 2))
                return;
        ext = (struct sysinfo_1_2_2_extension *)
                ((unsigned long) info + info->acc_offset);
@@ -152,7 +173,7 @@ static void stsi_1_2_2(struct seq_file *m, struct sysinfo_1_2_2 *info)
 
 static void stsi_2_2_2(struct seq_file *m, struct sysinfo_2_2_2 *info)
 {
-       if (stsi(info, 2, 2, 2) == -ENOSYS)
+       if (stsi(info, 2, 2, 2))
                return;
        EBCASC(info->name, sizeof(info->name));
        seq_putc(m, '\n');
@@ -179,7 +200,7 @@ static void stsi_3_2_2(struct seq_file *m, struct sysinfo_3_2_2 *info)
 {
        int i;
 
-       if (stsi(info, 3, 2, 2) == -ENOSYS)
+       if (stsi(info, 3, 2, 2))
                return;
        for (i = 0; i < info->count; i++) {
                EBCASC(info->vm[i].name, sizeof(info->vm[i].name));
@@ -202,7 +223,7 @@ static int sysinfo_show(struct seq_file *m, void *v)
 
        if (!info)
                return 0;
-       level = stsi_0();
+       level = stsi(NULL, 0, 0, 0);
        if (level >= 1)
                stsi_1_1_1(m, info);
        if (level >= 1)
@@ -365,7 +386,7 @@ void s390_adjust_jiffies(void)
        if (!info)
                return;
 
-       if (stsi(info, 1, 2, 2) != -ENOSYS) {
+       if (stsi(info, 1, 2, 2) == 0) {
                /*
                 * Major sigh. The cpu capability encoding is "special".
                 * If the first 9 bits of info->capability are 0 then it

diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 60da903..310be61 100644 (file)
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -211,7 +211,7 @@ static void handle_stsi_3_2_2(struct kvm_vcpu *vcpu, struct sysinfo_3_2_2 *mem)
        spin_unlock(&fi->lock);
 
        /* deal with other level 3 hypervisors */
-       if (stsi(mem, 3, 2, 2) == -ENOSYS)
+       if (stsi(mem, 3, 2, 2))
                mem->count = 0;
        if (mem->count < 8)
                mem->count++;
@@ -259,7 +259,7 @@ static int handle_stsi(struct kvm_vcpu *vcpu)
                mem = get_zeroed_page(GFP_KERNEL);
                if (!mem)
                        goto out_fail;
-               if (stsi((void *) mem, fc, sel1, sel2) == -ENOSYS)
+               if (stsi((void *) mem, fc, sel1, sel2))
                        goto out_mem;
                break;
        case 3:

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 7a8b096..cf6da7f 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -2993,7 +2993,7 @@ static void qeth_get_trap_id(struct qeth_card *card, struct qeth_trap_id *tid)
        struct sysinfo_2_2_2 *info222 = (struct sysinfo_2_2_2 *)info;
        struct sysinfo_3_2_2 *info322 = (struct sysinfo_3_2_2 *)info;
        struct ccw_dev_id ccwid;
-       int level, rc;
+       int level;
 
        tid->chpid = card->info.chpid;
        ccw_device_get_id(CARD_RDEV(card), &ccwid);
@@ -3001,17 +3001,10 @@ static void qeth_get_trap_id(struct qeth_card *card, struct qeth_trap_id *tid)
        tid->devno = ccwid.devno;
        if (!info)
                return;
-
-       rc = stsi(NULL, 0, 0, 0);
-       if (rc == -ENOSYS)
-               level = rc;
-       else
-               level = (((unsigned int) rc) >> 28);
-
-       if ((level >= 2) && (stsi(info222, 2, 2, 2) != -ENOSYS))
+       level = stsi(NULL, 0, 0, 0);
+       if ((level >= 2) && (stsi(info222, 2, 2, 2) == 0))
                tid->lparnr = info222->lpar_number;
-
-       if ((level >= 3) && (stsi(info322, 3, 2, 2) != -ENOSYS)) {
+       if ((level >= 3) && (stsi(info322, 3, 2, 2) == 0)) {
                EBCASC(info322->vm[0].name, sizeof(info322->vm[0].name));
                memcpy(tid->vmname, info322->vm[0].name, sizeof(tid->vmname));
        }