xen: remove support for non-PAE 32-bit

Non-PAE operation has been deprecated in Xen for a while, and is
rarely tested or used.  xen-unstable has now officially dropped
non-PAE support.  Since Xen/pvops' non-PAE support has also been
broken for a while, we may as well completely drop it altogether.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

6 files changed, 27 insertions, 77 deletions

diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index 2e641be2737e..525b108411bd 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -6,7 +6,7 @@ config XEN
         bool "Xen guest support"
         select PARAVIRT
         depends on X86_32
-        depends on X86_CMPXCHG && X86_TSC && !(X86_VISWS || X86_VOYAGER)
+        depends on X86_CMPXCHG && X86_TSC && X86_PAE && !(X86_VISWS || X86_VOYAGER)
         help
           This is the Linux Xen port.  Enabling this will allow the
           kernel to boot in a paravirtualized environment under the
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index c048de34d6a1..f09c1c69c37a 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -785,38 +785,35 @@ static __init void xen_set_pte_init(pte_t *ptep, pte_t pte)
 static __init void xen_pagetable_setup_start(pgd_t *base)
 {
         pgd_t *xen_pgd = (pgd_t *)xen_start_info->pt_base;
+        int i;
 
         /* special set_pte for pagetable initialization */
         pv_mmu_ops.set_pte = xen_set_pte_init;
 
         init_mm.pgd = base;
         /*
-         * copy top-level of Xen-supplied pagetable into place.  For
-         * !PAE we can use this as-is, but for PAE it is a stand-in
-         * while we copy the pmd pages.
+         * copy top-level of Xen-supplied pagetable into place.  This
+         * is a stand-in while we copy the pmd pages.
          */
         memcpy(base, xen_pgd, PTRS_PER_PGD * sizeof(pgd_t));
 
-        if (PTRS_PER_PMD > 1) {
-                int i;
-                /*
-                 * For PAE, need to allocate new pmds, rather than
-                 * share Xen's, since Xen doesn't like pmd's being
-                 * shared between address spaces.
-                 */
-                for (i = 0; i < PTRS_PER_PGD; i++) {
-                        if (pgd_val_ma(xen_pgd[i]) & _PAGE_PRESENT) {
-                                pmd_t *pmd = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
+        /*
+         * For PAE, need to allocate new pmds, rather than
+         * share Xen's, since Xen doesn't like pmd's being
+         * shared between address spaces.
+         */
+        for (i = 0; i < PTRS_PER_PGD; i++) {
+                if (pgd_val_ma(xen_pgd[i]) & _PAGE_PRESENT) {
+                        pmd_t *pmd = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
 
-                                memcpy(pmd, (void *)pgd_page_vaddr(xen_pgd[i]),
-                                       PAGE_SIZE);
+                        memcpy(pmd, (void *)pgd_page_vaddr(xen_pgd[i]),
+                               PAGE_SIZE);
 
-                                make_lowmem_page_readonly(pmd);
+                        make_lowmem_page_readonly(pmd);
 
-                                set_pgd(&base[i], __pgd(1 + __pa(pmd)));
-                        } else
-                                pgd_clear(&base[i]);
-                }
+                        set_pgd(&base[i], __pgd(1 + __pa(pmd)));
+                } else
+                        pgd_clear(&base[i]);
         }
 
         /* make sure zero_page is mapped RO so we can use it in pagetables */
@@ -873,17 +870,7 @@ static __init void xen_pagetable_setup_done(pgd_t *base)
 
         /* Actually pin the pagetable down, but we can't set PG_pinned
            yet because the page structures don't exist yet. */
-        {
-                unsigned level;
-
-#ifdef CONFIG_X86_PAE
-                level = MMUEXT_PIN_L3_TABLE;
-#else
-                level = MMUEXT_PIN_L2_TABLE;
-#endif
-
-                pin_pagetable_pfn(level, PFN_DOWN(__pa(base)));
-        }
+        pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(base)));
 }
 
 /* This is called once we have the cpu_possible_map */
@@ -1093,7 +1080,6 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = {
         .make_pte = xen_make_pte,
         .make_pgd = xen_make_pgd,
 
-#ifdef CONFIG_X86_PAE
         .set_pte_atomic = xen_set_pte_atomic,
         .set_pte_present = xen_set_pte_at,
         .set_pud = xen_set_pud,
@@ -1102,7 +1088,6 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = {
 
         .make_pmd = xen_make_pmd,
         .pmd_val = xen_pmd_val,
-#endif  /* PAE */
 
         .activate_mm = xen_activate_mm,
         .dup_mmap = xen_dup_mmap,
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 265601d5a6ae..df40bf74ea75 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -228,7 +228,7 @@ pmdval_t xen_pmd_val(pmd_t pmd)
 {
         return pte_mfn_to_pfn(pmd.pmd);
 }
-#ifdef CONFIG_X86_PAE
+
 void xen_set_pud(pud_t *ptr, pud_t val)
 {
         struct multicall_space mcs;
@@ -276,12 +276,6 @@ pmd_t xen_make_pmd(pmdval_t pmd)
         pmd = pte_pfn_to_mfn(pmd);
         return native_make_pmd(pmd);
 }
-#else  /* !PAE */
-void xen_set_pte(pte_t *ptep, pte_t pte)
-{
-        *ptep = pte;
-}
-#endif  /* CONFIG_X86_PAE */
 
 /*
   (Yet another) pagetable walker.  This one is intended for pinning a
@@ -434,8 +428,6 @@ static int pin_page(struct page *page, enum pt_level level)
    read-only, and can be pinned. */
 void xen_pgd_pin(pgd_t *pgd)
 {
-        unsigned level;
-
         xen_mc_batch();
 
         if (pgd_walk(pgd, pin_page, TASK_SIZE)) {
@@ -445,14 +437,7 @@ void xen_pgd_pin(pgd_t *pgd)
                 xen_mc_batch();
         }
 
-#ifdef CONFIG_X86_PAE
-        level = MMUEXT_PIN_L3_TABLE;
-#else
-        level = MMUEXT_PIN_L2_TABLE;
-#endif
-
-        xen_do_pin(level, PFN_DOWN(__pa(pgd)));
-
+        xen_do_pin(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(pgd)));
         xen_mc_issue(0);
 }
 
diff --git a/arch/x86/xen/mmu.h b/arch/x86/xen/mmu.h
index b5e189b1519d..5fe961caffd4 100644
--- a/arch/x86/xen/mmu.h
+++ b/arch/x86/xen/mmu.h
@@ -37,14 +37,13 @@ void xen_exit_mmap(struct mm_struct *mm);
 void xen_pgd_pin(pgd_t *pgd);
 //void xen_pgd_unpin(pgd_t *pgd);
 
-#ifdef CONFIG_X86_PAE
-unsigned long long xen_pte_val(pte_t);
-unsigned long long xen_pmd_val(pmd_t);
-unsigned long long xen_pgd_val(pgd_t);
+pteval_t xen_pte_val(pte_t);
+pmdval_t xen_pmd_val(pmd_t);
+pgdval_t xen_pgd_val(pgd_t);
 
-pte_t xen_make_pte(unsigned long long);
-pmd_t xen_make_pmd(unsigned long long);
-pgd_t xen_make_pgd(unsigned long long);
+pte_t xen_make_pte(pteval_t);
+pmd_t xen_make_pmd(pmdval_t);
+pgd_t xen_make_pgd(pgdval_t);
 
 void xen_set_pte_at(struct mm_struct *mm, unsigned long addr,
                     pte_t *ptep, pte_t pteval);
@@ -53,15 +52,4 @@ void xen_set_pud(pud_t *ptr, pud_t val);
 void xen_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
 void xen_pmd_clear(pmd_t *pmdp);
 
-
-#else
-unsigned long xen_pte_val(pte_t);
-unsigned long xen_pmd_val(pmd_t);
-unsigned long xen_pgd_val(pgd_t);
-
-pte_t xen_make_pte(unsigned long);
-pmd_t xen_make_pmd(unsigned long);
-pgd_t xen_make_pgd(unsigned long);
-#endif
-
 #endif  /* _XEN_MMU_H */
diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
index 3175e973fd0d..6ec3b4f7719b 100644
--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -30,11 +30,7 @@ ENTRY(hypercall_page)
         ELFNOTE(Xen, XEN_ELFNOTE_ENTRY,          .long  startup_xen)
         ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, .long  hypercall_page)
         ELFNOTE(Xen, XEN_ELFNOTE_FEATURES,       .asciz "!writable_page_tables|pae_pgdir_above_4gb")
-#ifdef CONFIG_X86_PAE
         ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE,       .asciz "yes")
-#else
-        ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE,       .asciz "no")
-#endif
         ELFNOTE(Xen, XEN_ELFNOTE_LOADER,         .asciz "generic")
 
 #endif /*CONFIG_XEN */
diff --git a/include/asm-x86/xen/page.h b/include/asm-x86/xen/page.h
index baf3a4dce28c..e11f24038b1d 100644
--- a/include/asm-x86/xen/page.h
+++ b/include/asm-x86/xen/page.h
@@ -150,13 +150,9 @@ static inline pte_t __pte_ma(pteval_t x)
         return (pte_t) { .pte = x };
 }
 
-#ifdef CONFIG_X86_PAE
 #define pmd_val_ma(v) ((v).pmd)
 #define pud_val_ma(v) ((v).pgd.pgd)
 #define __pmd_ma(x)     ((pmd_t) { (x) } )
-#else  /* !X86_PAE */
-#define pmd_val_ma(v)   ((v).pud.pgd.pgd)
-#endif  /* CONFIG_X86_PAE */
 
 #define pgd_val_ma(x)   ((x).pgd)