[PATCH] mm: init_mm without ptlock

First step in pushing down the page_table_lock.  init_mm.page_table_lock has
been used throughout the architectures (usually for ioremap): not to serialize
kernel address space allocation (that's usually vmlist_lock), but because
pud_alloc,pmd_alloc,pte_alloc_kernel expect caller holds it.

Reverse that: don't lock or unlock init_mm.page_table_lock in any of the
architectures; instead rely on pud_alloc,pmd_alloc,pte_alloc_kernel to take
and drop it when allocating a new one, to check lest a racing task already
did.  Similarly no page_table_lock in vmalloc's map_vm_area.

Some temporary ugliness in __pud_alloc and __pmd_alloc: since they also handle
user mms, which are converted only by a later patch, for now they have to lock
differently according to whether or not it's init_mm.

If sources get muddled, there's a danger that an arch source taking
init_mm.page_table_lock will be mixed with common source also taking it (or
neither take it).  So break the rules and make another change, which should
break the build for such a mismatch: remove the redundant mm arg from
pte_alloc_kernel (ppc64 scrapped its distinct ioremap_mm in 2.6.13).

Exceptions: arm26 used pte_alloc_kernel on user mm, now pte_alloc_map; ia64
used pte_alloc_map on init_mm, now pte_alloc_kernel; parisc had bad args to
pmd_alloc and pte_alloc_kernel in unused USE_HPPA_IOREMAP code; ppc64
map_io_page forgot to unlock on failure; ppc mmu_mapin_ram and ppc64 im_free
took page_table_lock for no good reason.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/arch/alpha/mm/remap.c b/arch/alpha/mm/remap.c
index 19817ad..a78356c 100644 (file)
--- a/arch/alpha/mm/remap.c
+++ b/arch/alpha/mm/remap.c
@@ -2,7 +2,6 @@
 #include <asm/pgalloc.h>
 #include <asm/cacheflush.h>
 
-/* called with the page_table_lock held */
 static inline void 
 remap_area_pte(pte_t * pte, unsigned long address, unsigned long size, 
               unsigned long phys_addr, unsigned long flags)
@@ -31,7 +30,6 @@ remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
        } while (address && (address < end));
 }
 
-/* called with the page_table_lock held */
 static inline int 
 remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size, 
               unsigned long phys_addr, unsigned long flags)
@@ -46,7 +44,7 @@ remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
        if (address >= end)
                BUG();
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, 
@@ -70,7 +68,6 @@ __alpha_remap_area_pages(unsigned long address, unsigned long phys_addr,
        flush_cache_all();
        if (address >= end)
                BUG();
-       spin_lock(&init_mm.page_table_lock);
        do {
                pmd_t *pmd;
                pmd = pmd_alloc(&init_mm, dir, address);
@@ -84,7 +81,6 @@ __alpha_remap_area_pages(unsigned long address, unsigned long phys_addr,
                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                dir++;
        } while (address && (address < end));
-       spin_unlock(&init_mm.page_table_lock);
        return error;
 }
 

diff --git a/arch/arm/mm/consistent.c b/arch/arm/mm/consistent.c
index 82f4d5e..47b0b76 100644 (file)
--- a/arch/arm/mm/consistent.c
+++ b/arch/arm/mm/consistent.c
@@ -397,8 +397,6 @@ static int __init consistent_init(void)
        pte_t *pte;
        int ret = 0;
 
-       spin_lock(&init_mm.page_table_lock);
-
        do {
                pgd = pgd_offset(&init_mm, CONSISTENT_BASE);
                pmd = pmd_alloc(&init_mm, pgd, CONSISTENT_BASE);
@@ -409,7 +407,7 @@ static int __init consistent_init(void)
                }
                WARN_ON(!pmd_none(*pmd));
 
-               pte = pte_alloc_kernel(&init_mm, pmd, CONSISTENT_BASE);
+               pte = pte_alloc_kernel(pmd, CONSISTENT_BASE);
                if (!pte) {
                        printk(KERN_ERR "%s: no pte tables\n", __func__);
                        ret = -ENOMEM;
@@ -419,8 +417,6 @@ static int __init consistent_init(void)
                consistent_pte = pte;
        } while (0);
 
-       spin_unlock(&init_mm.page_table_lock);
-
        return ret;
 }
 

diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 6fb1258..0f128c2 100644 (file)
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -75,7 +75,7 @@ remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
 
        pgprot = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY | L_PTE_WRITE | flags);
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, address + phys_addr, pgprot);
@@ -97,7 +97,6 @@ remap_area_pages(unsigned long start, unsigned long phys_addr,
        phys_addr -= address;
        dir = pgd_offset(&init_mm, address);
        BUG_ON(address >= end);
-       spin_lock(&init_mm.page_table_lock);
        do {
                pmd_t *pmd = pmd_alloc(&init_mm, dir, address);
                if (!pmd) {
@@ -114,7 +113,6 @@ remap_area_pages(unsigned long start, unsigned long phys_addr,
                dir++;
        } while (address && (address < end));
 
-       spin_unlock(&init_mm.page_table_lock);
        flush_cache_vmap(start, end);
        return err;
 }

diff --git a/arch/arm26/mm/memc.c b/arch/arm26/mm/memc.c
index 8e8a2bb..d6b008b 100644 (file)
--- a/arch/arm26/mm/memc.c
+++ b/arch/arm26/mm/memc.c
@@ -92,7 +92,7 @@ pgd_t *get_pgd_slow(struct mm_struct *mm)
        if (!new_pmd)
                goto no_pmd;
 
-       new_pte = pte_alloc_kernel(mm, new_pmd, 0);
+       new_pte = pte_alloc_map(mm, new_pmd, 0);
        if (!new_pte)
                goto no_pte;
 
@@ -101,6 +101,7 @@ pgd_t *get_pgd_slow(struct mm_struct *mm)
        init_pte = pte_offset(init_pmd, 0);
 
        set_pte(new_pte, *init_pte);
+       pte_unmap(new_pte);
 
        /*
         * the page table entries are zeroed

diff --git a/arch/cris/mm/ioremap.c b/arch/cris/mm/ioremap.c
index ebba11e..a92ac98 100644 (file)
--- a/arch/cris/mm/ioremap.c
+++ b/arch/cris/mm/ioremap.c
@@ -52,7 +52,7 @@ static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned lo
        if (address >= end)
                BUG();
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, address + phys_addr, prot);
@@ -74,7 +74,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
        flush_cache_all();
        if (address >= end)
                BUG();
-       spin_lock(&init_mm.page_table_lock);
        do {
                pud_t *pud;
                pmd_t *pmd;
@@ -94,7 +93,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                dir++;
        } while (address && (address < end));
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return error;
 }

diff --git a/arch/frv/mm/dma-alloc.c b/arch/frv/mm/dma-alloc.c
index cfc4f97..342823a 100644 (file)
--- a/arch/frv/mm/dma-alloc.c
+++ b/arch/frv/mm/dma-alloc.c
@@ -55,21 +55,18 @@ static int map_page(unsigned long va, unsigned long pa, pgprot_t prot)
        pte_t *pte;
        int err = -ENOMEM;
 
-       spin_lock(&init_mm.page_table_lock);
-
        /* Use upper 10 bits of VA to index the first level map */
        pge = pgd_offset_k(va);
        pue = pud_offset(pge, va);
        pme = pmd_offset(pue, va);
 
        /* Use middle 10 bits of VA to index the second-level map */
-       pte = pte_alloc_kernel(&init_mm, pme, va);
+       pte = pte_alloc_kernel(pme, va);
        if (pte != 0) {
                err = 0;
                set_pte(pte, mk_pte_phys(pa & PAGE_MASK, prot));
        }
 
-       spin_unlock(&init_mm.page_table_lock);
        return err;
 }
 

diff --git a/arch/i386/mm/ioremap.c b/arch/i386/mm/ioremap.c
index f379b8d..5d09de8 100644 (file)
--- a/arch/i386/mm/ioremap.c
+++ b/arch/i386/mm/ioremap.c
@@ -28,7 +28,7 @@ static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
        unsigned long pfn;
 
        pfn = phys_addr >> PAGE_SHIFT;
-       pte = pte_alloc_kernel(&init_mm, pmd, addr);
+       pte = pte_alloc_kernel(pmd, addr);
        if (!pte)
                return -ENOMEM;
        do {
@@ -87,14 +87,12 @@ static int ioremap_page_range(unsigned long addr,
        flush_cache_all();
        phys_addr -= addr;
        pgd = pgd_offset_k(addr);
-       spin_lock(&init_mm.page_table_lock);
        do {
                next = pgd_addr_end(addr, end);
                err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, flags);
                if (err)
                        break;
        } while (pgd++, addr = next, addr != end);
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return err;
 }

diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 0063b2c..e3215ba 100644 (file)
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -275,26 +275,21 @@ put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot)
 
        pgd = pgd_offset_k(address);            /* note: this is NOT pgd_offset()! */
 
-       spin_lock(&init_mm.page_table_lock);
        {
                pud = pud_alloc(&init_mm, pgd, address);
                if (!pud)
                        goto out;
-
                pmd = pmd_alloc(&init_mm, pud, address);
                if (!pmd)
                        goto out;
-               pte = pte_alloc_map(&init_mm, pmd, address);
+               pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        goto out;
-               if (!pte_none(*pte)) {
-                       pte_unmap(pte);
+               if (!pte_none(*pte))
                        goto out;
-               }
                set_pte(pte, mk_pte(page, pgprot));
-               pte_unmap(pte);
        }
-  out: spin_unlock(&init_mm.page_table_lock);
+  out:
        /* no need for flush_tlb */
        return page;
 }

diff --git a/arch/m32r/mm/ioremap.c b/arch/m32r/mm/ioremap.c
index 70c5905..a151849 100644 (file)
--- a/arch/m32r/mm/ioremap.c
+++ b/arch/m32r/mm/ioremap.c
@@ -67,7 +67,7 @@ remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
        if (address >= end)
                BUG();
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, address + phys_addr, flags);
@@ -90,7 +90,6 @@ remap_area_pages(unsigned long address, unsigned long phys_addr,
        flush_cache_all();
        if (address >= end)
                BUG();
-       spin_lock(&init_mm.page_table_lock);
        do {
                pmd_t *pmd;
                pmd = pmd_alloc(&init_mm, dir, address);
@@ -104,7 +103,6 @@ remap_area_pages(unsigned long address, unsigned long phys_addr,
                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                dir++;
        } while (address && (address < end));
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return error;
 }

diff --git a/arch/m68k/mm/kmap.c b/arch/m68k/mm/kmap.c
index 5dcb3fa..fe2383e 100644 (file)
--- a/arch/m68k/mm/kmap.c
+++ b/arch/m68k/mm/kmap.c
@@ -201,7 +201,7 @@ void *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag)
                        virtaddr += PTRTREESIZE;
                        size -= PTRTREESIZE;
                } else {
-                       pte_dir = pte_alloc_kernel(&init_mm, pmd_dir, virtaddr);
+                       pte_dir = pte_alloc_kernel(pmd_dir, virtaddr);
                        if (!pte_dir) {
                                printk("ioremap: no mem for pte_dir\n");
                                return NULL;

diff --git a/arch/m68k/sun3x/dvma.c b/arch/m68k/sun3x/dvma.c
index 32e55ad..117481e 100644 (file)
--- a/arch/m68k/sun3x/dvma.c
+++ b/arch/m68k/sun3x/dvma.c
@@ -116,7 +116,7 @@ inline int dvma_map_cpu(unsigned long kaddr,
                        pte_t *pte;
                        unsigned long end3;
 
-                       if((pte = pte_alloc_kernel(&init_mm, pmd, vaddr)) == NULL) {
+                       if((pte = pte_alloc_kernel(pmd, vaddr)) == NULL) {
                                ret = -ENOMEM;
                                goto out;
                        }

diff --git a/arch/mips/mm/ioremap.c b/arch/mips/mm/ioremap.c
index 9c44ca7..3101d1d 100644 (file)
--- a/arch/mips/mm/ioremap.c
+++ b/arch/mips/mm/ioremap.c
@@ -55,7 +55,7 @@ static inline int remap_area_pmd(pmd_t * pmd, unsigned long address,
        if (address >= end)
                BUG();
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, address + phys_addr, flags);
@@ -77,7 +77,6 @@ static int remap_area_pages(unsigned long address, phys_t phys_addr,
        flush_cache_all();
        if (address >= end)
                BUG();
-       spin_lock(&init_mm.page_table_lock);
        do {
                pud_t *pud;
                pmd_t *pmd;
@@ -96,7 +95,6 @@ static int remap_area_pages(unsigned long address, phys_t phys_addr,
                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                dir++;
        } while (address && (address < end));
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return error;
 }

diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
index ae6213d..f94a02e 100644 (file)
--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -114,7 +114,7 @@ static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
        if (end > PGDIR_SIZE)
                end = PGDIR_SIZE;
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, vaddr);
+               pte_t * pte = pte_alloc_kernel(pmd, vaddr);
                if (!pte)
                        return -ENOMEM;
                if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))

diff --git a/arch/parisc/mm/ioremap.c b/arch/parisc/mm/ioremap.c
index f2df502..5c7a1b3 100644 (file)
--- a/arch/parisc/mm/ioremap.c
+++ b/arch/parisc/mm/ioremap.c
@@ -52,7 +52,7 @@ static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned lo
        if (address >= end)
                BUG();
        do {
-               pte_t * pte = pte_alloc_kernel(NULL, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, address + phys_addr, flags);
@@ -75,10 +75,9 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
        flush_cache_all();
        if (address >= end)
                BUG();
-       spin_lock(&init_mm.page_table_lock);
        do {
                pmd_t *pmd;
-               pmd = pmd_alloc(dir, address);
+               pmd = pmd_alloc(&init_mm, dir, address);
                error = -ENOMEM;
                if (!pmd)
                        break;
@@ -89,7 +88,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                dir++;
        } while (address && (address < end));
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return error;
 }

diff --git a/arch/ppc/kernel/dma-mapping.c b/arch/ppc/kernel/dma-mapping.c
index 0f710d2..685fd0d 100644 (file)
--- a/arch/ppc/kernel/dma-mapping.c
+++ b/arch/ppc/kernel/dma-mapping.c
@@ -335,8 +335,6 @@ static int __init dma_alloc_init(void)
        pte_t *pte;
        int ret = 0;
 
-       spin_lock(&init_mm.page_table_lock);
-
        do {
                pgd = pgd_offset(&init_mm, CONSISTENT_BASE);
                pmd = pmd_alloc(&init_mm, pgd, CONSISTENT_BASE);
@@ -347,7 +345,7 @@ static int __init dma_alloc_init(void)
                }
                WARN_ON(!pmd_none(*pmd));
 
-               pte = pte_alloc_kernel(&init_mm, pmd, CONSISTENT_BASE);
+               pte = pte_alloc_kernel(pmd, CONSISTENT_BASE);
                if (!pte) {
                        printk(KERN_ERR "%s: no pte tables\n", __func__);
                        ret = -ENOMEM;
@@ -357,8 +355,6 @@ static int __init dma_alloc_init(void)
                consistent_pte = pte;
        } while (0);
 
-       spin_unlock(&init_mm.page_table_lock);
-
        return ret;
 }
 

diff --git a/arch/ppc/mm/4xx_mmu.c b/arch/ppc/mm/4xx_mmu.c
index b7bcbc2..4d006aa 100644 (file)
--- a/arch/ppc/mm/4xx_mmu.c
+++ b/arch/ppc/mm/4xx_mmu.c
@@ -110,13 +110,11 @@ unsigned long __init mmu_mapin_ram(void)
                pmd_t *pmdp;
                unsigned long val = p | _PMD_SIZE_16M | _PAGE_HWEXEC | _PAGE_HWWRITE;
 
-               spin_lock(&init_mm.page_table_lock);
                pmdp = pmd_offset(pgd_offset_k(v), v);
                pmd_val(*pmdp++) = val;
                pmd_val(*pmdp++) = val;
                pmd_val(*pmdp++) = val;
                pmd_val(*pmdp++) = val;
-               spin_unlock(&init_mm.page_table_lock);
 
                v += LARGE_PAGE_SIZE_16M;
                p += LARGE_PAGE_SIZE_16M;
@@ -127,10 +125,8 @@ unsigned long __init mmu_mapin_ram(void)
                pmd_t *pmdp;
                unsigned long val = p | _PMD_SIZE_4M | _PAGE_HWEXEC | _PAGE_HWWRITE;
 
-               spin_lock(&init_mm.page_table_lock);
                pmdp = pmd_offset(pgd_offset_k(v), v);
                pmd_val(*pmdp) = val;
-               spin_unlock(&init_mm.page_table_lock);
 
                v += LARGE_PAGE_SIZE_4M;
                p += LARGE_PAGE_SIZE_4M;

diff --git a/arch/ppc/mm/pgtable.c b/arch/ppc/mm/pgtable.c
index 43505b1..6ea9185 100644 (file)
--- a/arch/ppc/mm/pgtable.c
+++ b/arch/ppc/mm/pgtable.c
@@ -280,18 +280,16 @@ map_page(unsigned long va, phys_addr_t pa, int flags)
        pte_t *pg;
        int err = -ENOMEM;
 
-       spin_lock(&init_mm.page_table_lock);
        /* Use upper 10 bits of VA to index the first level map */
        pd = pmd_offset(pgd_offset_k(va), va);
        /* Use middle 10 bits of VA to index the second-level map */
-       pg = pte_alloc_kernel(&init_mm, pd, va);
+       pg = pte_alloc_kernel(pd, va);
        if (pg != 0) {
                err = 0;
                set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, __pgprot(flags)));
                if (mem_init_done)
                        flush_HPTE(0, va, pmd_val(*pd));
        }
-       spin_unlock(&init_mm.page_table_lock);
        return err;
 }
 

diff --git a/arch/ppc64/mm/imalloc.c b/arch/ppc64/mm/imalloc.c
index c65b87b..f4ca29c 100644 (file)
--- a/arch/ppc64/mm/imalloc.c
+++ b/arch/ppc64/mm/imalloc.c
@@ -300,12 +300,7 @@ void im_free(void * addr)
        for (p = &imlist ; (tmp = *p) ; p = &tmp->next) {
                if (tmp->addr == addr) {
                        *p = tmp->next;
-
-                       /* XXX: do we need the lock? */
-                       spin_lock(&init_mm.page_table_lock);
                        unmap_vm_area(tmp);
-                       spin_unlock(&init_mm.page_table_lock);
-
                        kfree(tmp);
                        up(&imlist_sem);
                        return;

diff --git a/arch/ppc64/mm/init.c b/arch/ppc64/mm/init.c
index be64b15..a45584b 100644 (file)
--- a/arch/ppc64/mm/init.c
+++ b/arch/ppc64/mm/init.c
@@ -155,7 +155,6 @@ static int map_io_page(unsigned long ea, unsigned long pa, int flags)
        unsigned long vsid;
 
        if (mem_init_done) {
-               spin_lock(&init_mm.page_table_lock);
                pgdp = pgd_offset_k(ea);
                pudp = pud_alloc(&init_mm, pgdp, ea);
                if (!pudp)
@@ -163,12 +162,11 @@ static int map_io_page(unsigned long ea, unsigned long pa, int flags)
                pmdp = pmd_alloc(&init_mm, pudp, ea);
                if (!pmdp)
                        return -ENOMEM;
-               ptep = pte_alloc_kernel(&init_mm, pmdp, ea);
+               ptep = pte_alloc_kernel(pmdp, ea);
                if (!ptep)
                        return -ENOMEM;
                set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT,
                                                          __pgprot(flags)));
-               spin_unlock(&init_mm.page_table_lock);
        } else {
                unsigned long va, vpn, hash, hpteg;
 

diff --git a/arch/s390/mm/ioremap.c b/arch/s390/mm/ioremap.c
index c6c39d8..0f6e9ec 100644 (file)
--- a/arch/s390/mm/ioremap.c
+++ b/arch/s390/mm/ioremap.c
@@ -58,7 +58,7 @@ static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned lo
        if (address >= end)
                BUG();
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, address + phys_addr, flags);
@@ -80,7 +80,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
        flush_cache_all();
        if (address >= end)
                BUG();
-       spin_lock(&init_mm.page_table_lock);
        do {
                pmd_t *pmd;
                pmd = pmd_alloc(&init_mm, dir, address);
@@ -94,7 +93,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                dir++;
        } while (address && (address < end));
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return 0;
 }

diff --git a/arch/sh/mm/ioremap.c b/arch/sh/mm/ioremap.c
index 9f490c2..e794e27 100644 (file)
--- a/arch/sh/mm/ioremap.c
+++ b/arch/sh/mm/ioremap.c
@@ -57,7 +57,7 @@ static inline int remap_area_pmd(pmd_t * pmd, unsigned long address,
        if (address >= end)
                BUG();
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, address + phys_addr, flags);
@@ -79,7 +79,6 @@ int remap_area_pages(unsigned long address, unsigned long phys_addr,
        flush_cache_all();
        if (address >= end)
                BUG();
-       spin_lock(&init_mm.page_table_lock);
        do {
                pmd_t *pmd;
                pmd = pmd_alloc(&init_mm, dir, address);
@@ -93,7 +92,6 @@ int remap_area_pages(unsigned long address, unsigned long phys_addr,
                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                dir++;
        } while (address && (address < end));
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return error;
 }

diff --git a/arch/sh64/mm/ioremap.c b/arch/sh64/mm/ioremap.c
index f4003da..fb1866f 100644 (file)
--- a/arch/sh64/mm/ioremap.c
+++ b/arch/sh64/mm/ioremap.c
@@ -79,7 +79,7 @@ static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned lo
                BUG();
 
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, address + phys_addr, flags);
@@ -101,7 +101,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
        flush_cache_all();
        if (address >= end)
                BUG();
-       spin_lock(&init_mm.page_table_lock);
        do {
                pmd_t *pmd = pmd_alloc(&init_mm, dir, address);
                error = -ENOMEM;
@@ -115,7 +114,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                dir++;
        } while (address && (address < end));
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return 0;
 }

diff --git a/arch/x86_64/mm/ioremap.c b/arch/x86_64/mm/ioremap.c
index 6972df4..ecf7acb 100644 (file)
--- a/arch/x86_64/mm/ioremap.c
+++ b/arch/x86_64/mm/ioremap.c
@@ -60,7 +60,7 @@ static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned lo
        if (address >= end)
                BUG();
        do {
-               pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+               pte_t * pte = pte_alloc_kernel(pmd, address);
                if (!pte)
                        return -ENOMEM;
                remap_area_pte(pte, address, end - address, address + phys_addr, flags);
@@ -105,7 +105,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
        flush_cache_all();
        if (address >= end)
                BUG();
-       spin_lock(&init_mm.page_table_lock);
        do {
                pud_t *pud;
                pud = pud_alloc(&init_mm, pgd, address);
@@ -119,7 +118,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                pgd++;
        } while (address && (address < end));
-       spin_unlock(&init_mm.page_table_lock);
        flush_tlb_all();
        return error;
 }

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 8939803..b9fa82b 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -706,7 +706,7 @@ static inline void unmap_shared_mapping_range(struct address_space *mapping,
 extern int vmtruncate(struct inode * inode, loff_t offset);
 extern pud_t *FASTCALL(__pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address));
 extern pmd_t *FASTCALL(__pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address));
-extern pte_t *FASTCALL(pte_alloc_kernel(struct mm_struct *mm, pmd_t *pmd, unsigned long address));
+extern pte_t *FASTCALL(pte_alloc_kernel(pmd_t *pmd, unsigned long address));
 extern pte_t *FASTCALL(pte_alloc_map(struct mm_struct *mm, pmd_t *pmd, unsigned long address));
 extern int install_page(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, struct page *page, pgprot_t prot);
 extern int install_file_pte(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, unsigned long pgoff, pgprot_t prot);

diff --git a/mm/memory.c b/mm/memory.c
index 692ad81..95a4553 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -307,28 +307,22 @@ out:
        return pte_offset_map(pmd, address);
 }
 
-pte_t fastcall * pte_alloc_kernel(struct mm_struct *mm, pmd_t *pmd, unsigned long address)
+pte_t fastcall * pte_alloc_kernel(pmd_t *pmd, unsigned long address)
 {
        if (!pmd_present(*pmd)) {
                pte_t *new;
 
-               spin_unlock(&mm->page_table_lock);
-               new = pte_alloc_one_kernel(mm, address);
-               spin_lock(&mm->page_table_lock);
+               new = pte_alloc_one_kernel(&init_mm, address);
                if (!new)
                        return NULL;
 
-               /*
-                * Because we dropped the lock, we should re-check the
-                * entry, as somebody else could have populated it..
-                */
-               if (pmd_present(*pmd)) {
+               spin_lock(&init_mm.page_table_lock);
+               if (pmd_present(*pmd))
                        pte_free_kernel(new);
-                       goto out;
-               }
-               pmd_populate_kernel(mm, pmd, new);
+               else
+                       pmd_populate_kernel(&init_mm, pmd, new);
+               spin_unlock(&init_mm.page_table_lock);
        }
-out:
        return pte_offset_kernel(pmd, address);
 }
 
@@ -2097,30 +2091,30 @@ int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 #ifndef __PAGETABLE_PUD_FOLDED
 /*
  * Allocate page upper directory.
- *
- * We've already handled the fast-path in-line, and we own the
- * page table lock.
+ * We've already handled the fast-path in-line.
  */
 pud_t fastcall *__pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
 {
        pud_t *new;
 
-       spin_unlock(&mm->page_table_lock);
+       if (mm != &init_mm)             /* Temporary bridging hack */
+               spin_unlock(&mm->page_table_lock);
        new = pud_alloc_one(mm, address);
-       spin_lock(&mm->page_table_lock);
-       if (!new)
+       if (!new) {
+               if (mm != &init_mm)     /* Temporary bridging hack */
+                       spin_lock(&mm->page_table_lock);
                return NULL;
+       }
 
-       /*
-        * Because we dropped the lock, we should re-check the
-        * entry, as somebody else could have populated it..
-        */
+       spin_lock(&mm->page_table_lock);
        if (pgd_present(*pgd)) {
                pud_free(new);
                goto out;
        }
        pgd_populate(mm, pgd, new);
  out:
+       if (mm == &init_mm)             /* Temporary bridging hack */
+               spin_unlock(&mm->page_table_lock);
        return pud_offset(pgd, address);
 }
 #endif /* __PAGETABLE_PUD_FOLDED */
@@ -2128,24 +2122,22 @@ pud_t fastcall *__pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long addr
 #ifndef __PAGETABLE_PMD_FOLDED
 /*
  * Allocate page middle directory.
- *
- * We've already handled the fast-path in-line, and we own the
- * page table lock.
+ * We've already handled the fast-path in-line.
  */
 pmd_t fastcall *__pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
 {
        pmd_t *new;
 
-       spin_unlock(&mm->page_table_lock);
+       if (mm != &init_mm)             /* Temporary bridging hack */
+               spin_unlock(&mm->page_table_lock);
        new = pmd_alloc_one(mm, address);
-       spin_lock(&mm->page_table_lock);
-       if (!new)
+       if (!new) {
+               if (mm != &init_mm)     /* Temporary bridging hack */
+                       spin_lock(&mm->page_table_lock);
                return NULL;
+       }
 
-       /*
-        * Because we dropped the lock, we should re-check the
-        * entry, as somebody else could have populated it..
-        */
+       spin_lock(&mm->page_table_lock);
 #ifndef __ARCH_HAS_4LEVEL_HACK
        if (pud_present(*pud)) {
                pmd_free(new);
@@ -2161,6 +2153,8 @@ pmd_t fastcall *__pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr
 #endif /* __ARCH_HAS_4LEVEL_HACK */
 
  out:
+       if (mm == &init_mm)             /* Temporary bridging hack */
+               spin_unlock(&mm->page_table_lock);
        return pmd_offset(pud, address);
 }
 #endif /* __PAGETABLE_PMD_FOLDED */

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 5e91205..54a90e8 100644 (file)
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -89,7 +89,7 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
 {
        pte_t *pte;
 
-       pte = pte_alloc_kernel(&init_mm, pmd, addr);
+       pte = pte_alloc_kernel(pmd, addr);
        if (!pte)
                return -ENOMEM;
        do {
@@ -147,14 +147,12 @@ int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page ***pages)
 
        BUG_ON(addr >= end);
        pgd = pgd_offset_k(addr);
-       spin_lock(&init_mm.page_table_lock);
        do {
                next = pgd_addr_end(addr, end);
                err = vmap_pud_range(pgd, addr, next, prot, pages);
                if (err)
                        break;
        } while (pgd++, addr = next, addr != end);
-       spin_unlock(&init_mm.page_table_lock);
        flush_cache_vmap((unsigned long) area->addr, end);
        return err;
 }