x86, asm: Clean up desc.h a bit

I have looked at this file and found it rather ugly - improve
readability a bit. No change in functionality.

Link: http://lkml.kernel.org/n/tip-incpt6y26yd8586idx65t9ll@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index 617bd56..7b439d9 100644 (file)
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -4,30 +4,33 @@
 #include <asm/desc_defs.h>
 #include <asm/ldt.h>
 #include <asm/mmu.h>
+
 #include <linux/smp.h>
 
-static inline void fill_ldt(struct desc_struct *desc,
-                           const struct user_desc *info)
-{
-       desc->limit0 = info->limit & 0x0ffff;
-       desc->base0 = info->base_addr & 0x0000ffff;
-
-       desc->base1 = (info->base_addr & 0x00ff0000) >> 16;
-       desc->type = (info->read_exec_only ^ 1) << 1;
-       desc->type |= info->contents << 2;
-       desc->s = 1;
-       desc->dpl = 0x3;
-       desc->p = info->seg_not_present ^ 1;
-       desc->limit = (info->limit & 0xf0000) >> 16;
-       desc->avl = info->useable;
-       desc->d = info->seg_32bit;
-       desc->g = info->limit_in_pages;
-       desc->base2 = (info->base_addr & 0xff000000) >> 24;
+static inline void fill_ldt(struct desc_struct *desc, const struct user_desc *info)
+{
+       desc->limit0            = info->limit & 0x0ffff;
+
+       desc->base0             = (info->base_addr & 0x0000ffff);
+       desc->base1             = (info->base_addr & 0x00ff0000) >> 16;
+
+       desc->type              = (info->read_exec_only ^ 1) << 1;
+       desc->type             |= info->contents << 2;
+
+       desc->s                 = 1;
+       desc->dpl               = 0x3;
+       desc->p                 = info->seg_not_present ^ 1;
+       desc->limit             = (info->limit & 0xf0000) >> 16;
+       desc->avl               = info->useable;
+       desc->d                 = info->seg_32bit;
+       desc->g                 = info->limit_in_pages;
+
+       desc->base2             = (info->base_addr & 0xff000000) >> 24;
        /*
         * Don't allow setting of the lm bit. It is useless anyway
         * because 64bit system calls require __USER_CS:
         */
-       desc->l = 0;
+       desc->l                 = 0;
 }
 
 extern struct desc_ptr idt_descr;
@@ -36,6 +39,7 @@ extern gate_desc idt_table[];
 struct gdt_page {
        struct desc_struct gdt[GDT_ENTRIES];
 } __attribute__((aligned(PAGE_SIZE)));
+
 DECLARE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page);
 
 static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
@@ -48,16 +52,16 @@ static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
 static inline void pack_gate(gate_desc *gate, unsigned type, unsigned long func,
                             unsigned dpl, unsigned ist, unsigned seg)
 {
-       gate->offset_low = PTR_LOW(func);
-       gate->segment = __KERNEL_CS;
-       gate->ist = ist;
-       gate->p = 1;
-       gate->dpl = dpl;
-       gate->zero0 = 0;
-       gate->zero1 = 0;
-       gate->type = type;
-       gate->offset_middle = PTR_MIDDLE(func);
-       gate->offset_high = PTR_HIGH(func);
+       gate->offset_low        = PTR_LOW(func);
+       gate->segment           = __KERNEL_CS;
+       gate->ist               = ist;
+       gate->p                 = 1;
+       gate->dpl               = dpl;
+       gate->zero0             = 0;
+       gate->zero1             = 0;
+       gate->type              = type;
+       gate->offset_middle     = PTR_MIDDLE(func);
+       gate->offset_high       = PTR_HIGH(func);
 }
 
 #else
@@ -66,8 +70,7 @@ static inline void pack_gate(gate_desc *gate, unsigned char type,
                             unsigned short seg)
 {
        gate->a = (seg << 16) | (base & 0xffff);
-       gate->b = (base & 0xffff0000) |
-                 (((0x80 | type | (dpl << 5)) & 0xff) << 8);
+       gate->b = (base & 0xffff0000) | (((0x80 | type | (dpl << 5)) & 0xff) << 8);
 }
 
 #endif
@@ -75,31 +78,29 @@ static inline void pack_gate(gate_desc *gate, unsigned char type,
 static inline int desc_empty(const void *ptr)
 {
        const u32 *desc = ptr;
+
        return !(desc[0] | desc[1]);
 }
 
 #ifdef CONFIG_PARAVIRT
 #include <asm/paravirt.h>
 #else
-#define load_TR_desc() native_load_tr_desc()
-#define load_gdt(dtr) native_load_gdt(dtr)
-#define load_idt(dtr) native_load_idt(dtr)
-#define load_tr(tr) asm volatile("ltr %0"::"m" (tr))
-#define load_ldt(ldt) asm volatile("lldt %0"::"m" (ldt))
-
-#define store_gdt(dtr) native_store_gdt(dtr)
-#define store_idt(dtr) native_store_idt(dtr)
-#define store_tr(tr) (tr = native_store_tr())
-
-#define load_TLS(t, cpu) native_load_tls(t, cpu)
-#define set_ldt native_set_ldt
-
-#define write_ldt_entry(dt, entry, desc)       \
-       native_write_ldt_entry(dt, entry, desc)
-#define write_gdt_entry(dt, entry, desc, type)         \
-       native_write_gdt_entry(dt, entry, desc, type)
-#define write_idt_entry(dt, entry, g)          \
-       native_write_idt_entry(dt, entry, g)
+#define load_TR_desc()                         native_load_tr_desc()
+#define load_gdt(dtr)                          native_load_gdt(dtr)
+#define load_idt(dtr)                          native_load_idt(dtr)
+#define load_tr(tr)                            asm volatile("ltr %0"::"m" (tr))
+#define load_ldt(ldt)                          asm volatile("lldt %0"::"m" (ldt))
+
+#define store_gdt(dtr)                         native_store_gdt(dtr)
+#define store_idt(dtr)                         native_store_idt(dtr)
+#define store_tr(tr)                           (tr = native_store_tr())
+
+#define load_TLS(t, cpu)                       native_load_tls(t, cpu)
+#define set_ldt                                        native_set_ldt
+
+#define write_ldt_entry(dt, entry, desc)       native_write_ldt_entry(dt, entry, desc)
+#define write_gdt_entry(dt, entry, desc, type) native_write_gdt_entry(dt, entry, desc, type)
+#define write_idt_entry(dt, entry, g)          native_write_idt_entry(dt, entry, g)
 
 static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries)
 {
@@ -112,33 +113,27 @@ static inline void paravirt_free_ldt(struct desc_struct *ldt, unsigned entries)
 
 #define store_ldt(ldt) asm("sldt %0" : "=m"(ldt))
 
-static inline void native_write_idt_entry(gate_desc *idt, int entry,
-                                         const gate_desc *gate)
+static inline void native_write_idt_entry(gate_desc *idt, int entry, const gate_desc *gate)
 {
        memcpy(&idt[entry], gate, sizeof(*gate));
 }
 
-static inline void native_write_ldt_entry(struct desc_struct *ldt, int entry,
-                                         const void *desc)
+static inline void native_write_ldt_entry(struct desc_struct *ldt, int entry, const void *desc)
 {
        memcpy(&ldt[entry], desc, 8);
 }
 
-static inline void native_write_gdt_entry(struct desc_struct *gdt, int entry,
-                                         const void *desc, int type)
+static inline void
+native_write_gdt_entry(struct desc_struct *gdt, int entry, const void *desc, int type)
 {
        unsigned int size;
+
        switch (type) {
-       case DESC_TSS:
-               size = sizeof(tss_desc);
-               break;
-       case DESC_LDT:
-               size = sizeof(ldt_desc);
-               break;
-       default:
-               size = sizeof(struct desc_struct);
-               break;
+       case DESC_TSS:  size = sizeof(tss_desc);        break;
+       case DESC_LDT:  size = sizeof(ldt_desc);        break;
+       default:        size = sizeof(*gdt);            break;
        }
+
        memcpy(&gdt[entry], desc, size);
 }
 
@@ -154,20 +149,21 @@ static inline void pack_descriptor(struct desc_struct *desc, unsigned long base,
 }
 
 
-static inline void set_tssldt_descriptor(void *d, unsigned long addr,
-                                        unsigned type, unsigned size)
+static inline void set_tssldt_descriptor(void *d, unsigned long addr, unsigned type, unsigned size)
 {
 #ifdef CONFIG_X86_64
        struct ldttss_desc64 *desc = d;
+
        memset(desc, 0, sizeof(*desc));
-       desc->limit0 = size & 0xFFFF;
-       desc->base0 = PTR_LOW(addr);
-       desc->base1 = PTR_MIDDLE(addr) & 0xFF;
-       desc->type = type;
-       desc->p = 1;
-       desc->limit1 = (size >> 16) & 0xF;
-       desc->base2 = (PTR_MIDDLE(addr) >> 8) & 0xFF;
-       desc->base3 = PTR_HIGH(addr);
+
+       desc->limit0            = size & 0xFFFF;
+       desc->base0             = PTR_LOW(addr);
+       desc->base1             = PTR_MIDDLE(addr) & 0xFF;
+       desc->type              = type;
+       desc->p                 = 1;
+       desc->limit1            = (size >> 16) & 0xF;
+       desc->base2             = (PTR_MIDDLE(addr) >> 8) & 0xFF;
+       desc->base3             = PTR_HIGH(addr);
 #else
        pack_descriptor((struct desc_struct *)d, addr, size, 0x80 | type, 0);
 #endif
@@ -237,14 +233,16 @@ static inline void native_store_idt(struct desc_ptr *dtr)
 static inline unsigned long native_store_tr(void)
 {
        unsigned long tr;
+
        asm volatile("str %0":"=r" (tr));
+
        return tr;
 }
 
 static inline void native_load_tls(struct thread_struct *t, unsigned int cpu)
 {
-       unsigned int i;
        struct desc_struct *gdt = get_cpu_gdt_table(cpu);
+       unsigned int i;
 
        for (i = 0; i < GDT_ENTRY_TLS_ENTRIES; i++)
                gdt[GDT_ENTRY_TLS_MIN + i] = t->tls_array[i];
@@ -313,6 +311,7 @@ static inline void _set_gate(int gate, unsigned type, void *addr,
                             unsigned dpl, unsigned ist, unsigned seg)
 {
        gate_desc s;
+
        pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg);
        /*
         * does not need to be atomic because it is only done once at
@@ -343,8 +342,9 @@ static inline void alloc_system_vector(int vector)
                set_bit(vector, used_vectors);
                if (first_system_vector > vector)
                        first_system_vector = vector;
-       } else
+       } else {
                BUG();
+       }
 }
 
 static inline void alloc_intr_gate(unsigned int n, void *addr)