[PATCH 09/21] mm: init_mm without ptlock

From: Hugh Dickins
Date: Wed Oct 12 2005 - 19:56:12 EST

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@xxxxxxxxxxx>
---

arch/alpha/mm/remap.c | 6 ----
arch/arm/mm/consistent.c | 6 ----
arch/arm/mm/ioremap.c | 4 --
arch/arm26/mm/memc.c | 3 +-
arch/cris/mm/ioremap.c | 4 --
arch/frv/mm/dma-alloc.c | 5 ---
arch/i386/mm/ioremap.c | 4 --
arch/ia64/mm/init.c | 11 ++-----
arch/m32r/mm/ioremap.c | 4 --
arch/m68k/mm/kmap.c | 2 -
arch/m68k/sun3x/dvma.c | 2 -
arch/mips/mm/ioremap.c | 4 --
arch/parisc/kernel/pci-dma.c | 2 -
arch/parisc/mm/ioremap.c | 6 +---
arch/ppc/kernel/dma-mapping.c | 6 ----
arch/ppc/mm/4xx_mmu.c | 4 --
arch/ppc/mm/pgtable.c | 4 --
arch/ppc64/mm/imalloc.c | 5 ---
arch/ppc64/mm/init.c | 4 --
arch/s390/mm/ioremap.c | 4 --
arch/sh/mm/ioremap.c | 4 --
arch/sh64/mm/ioremap.c | 4 --
arch/x86_64/mm/ioremap.c | 4 --
include/linux/mm.h | 2 -
mm/memory.c | 60 ++++++++++++++++++------------------------
mm/vmalloc.c | 4 --
26 files changed, 54 insertions(+), 114 deletions(-)

--- mm08/arch/alpha/mm/remap.c 2003-01-17 01:23:07.000000000 +0000
+++ mm09/arch/alpha/mm/remap.c 2005-10-11 23:55:53.000000000 +0100
@@ -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 lon
} 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 lon
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 a
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 a
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
return error;
}

--- mm08/arch/arm/mm/consistent.c 2005-06-17 20:48:29.000000000 +0100
+++ mm09/arch/arm/mm/consistent.c 2005-10-11 23:55:53.000000000 +0100
@@ -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;
}

--- mm08/arch/arm/mm/ioremap.c 2005-08-29 00:41:01.000000000 +0100
+++ mm09/arch/arm/mm/ioremap.c 2005-10-11 23:55:53.000000000 +0100
@@ -74,7 +74,7 @@ remap_area_pmd(pmd_t * pmd, unsigned lon

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);
@@ -96,7 +96,6 @@ remap_area_pages(unsigned long start, un
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) {
@@ -113,7 +112,6 @@ remap_area_pages(unsigned long start, un
dir++;
} while (address && (address < end));

- spin_unlock(&init_mm.page_table_lock);
flush_cache_vmap(start, end);
return err;
}
--- mm08/arch/arm26/mm/memc.c 2005-03-02 07:39:17.000000000 +0000
+++ mm09/arch/arm26/mm/memc.c 2005-10-11 23:55:53.000000000 +0100
@@ -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
--- mm08/arch/cris/mm/ioremap.c 2005-08-29 00:41:01.000000000 +0100
+++ mm09/arch/cris/mm/ioremap.c 2005-10-11 23:55:53.000000000 +0100
@@ -52,7 +52,7 @@ static inline int remap_area_pmd(pmd_t *
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 lon
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 lon
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
flush_tlb_all();
return error;
}
--- mm08/arch/frv/mm/dma-alloc.c 2005-03-02 07:39:19.000000000 +0000
+++ mm09/arch/frv/mm/dma-alloc.c 2005-10-11 23:55:53.000000000 +0100
@@ -55,21 +55,18 @@ static int map_page(unsigned long va, un
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;
}

--- mm08/arch/i386/mm/ioremap.c 2005-09-30 11:58:53.000000000 +0100
+++ mm09/arch/i386/mm/ioremap.c 2005-10-11 23:55:53.000000000 +0100
@@ -28,7 +28,7 @@ static int ioremap_pte_range(pmd_t *pmd,
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 l
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;
}
--- mm08/arch/ia64/mm/init.c 2005-10-11 23:55:38.000000000 +0100
+++ mm09/arch/ia64/mm/init.c 2005-10-11 23:55:53.000000000 +0100
@@ -275,26 +275,21 @@ put_kernel_page (struct page *page, unsi

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;
}
--- mm08/arch/m32r/mm/ioremap.c 2004-10-18 22:57:23.000000000 +0100
+++ mm09/arch/m32r/mm/ioremap.c 2005-10-11 23:55:53.000000000 +0100
@@ -67,7 +67,7 @@ remap_area_pmd(pmd_t * pmd, unsigned lon
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,
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,
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
flush_tlb_all();
return error;
}
--- mm08/arch/m68k/mm/kmap.c 2004-08-14 06:39:28.000000000 +0100
+++ mm09/arch/m68k/mm/kmap.c 2005-10-11 23:55:53.000000000 +0100
@@ -201,7 +201,7 @@ void *__ioremap(unsigned long physaddr,
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;
--- mm08/arch/m68k/sun3x/dvma.c 2004-06-16 06:20:37.000000000 +0100
+++ mm09/arch/m68k/sun3x/dvma.c 2005-10-11 23:55:53.000000000 +0100
@@ -116,7 +116,7 @@ inline int dvma_map_cpu(unsigned long ka
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;
}
--- mm08/arch/mips/mm/ioremap.c 2004-12-24 21:36:49.000000000 +0000
+++ mm09/arch/mips/mm/ioremap.c 2005-10-11 23:55:53.000000000 +0100
@@ -55,7 +55,7 @@ static inline int remap_area_pmd(pmd_t *
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 lon
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);
@@ -91,7 +90,6 @@ static int remap_area_pages(unsigned lon
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
flush_tlb_all();
return error;
}
--- mm08/arch/parisc/kernel/pci-dma.c 2005-06-17 20:48:29.000000000 +0100
+++ mm09/arch/parisc/kernel/pci-dma.c 2005-10-11 23:55:53.000000000 +0100
@@ -114,7 +114,7 @@ static inline int map_pmd_uncached(pmd_t
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))
--- mm08/arch/parisc/mm/ioremap.c 2005-03-02 07:38:55.000000000 +0000
+++ mm09/arch/parisc/mm/ioremap.c 2005-10-11 23:55:53.000000000 +0100
@@ -52,7 +52,7 @@ static inline int remap_area_pmd(pmd_t *
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 lon
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 lon
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
flush_tlb_all();
return error;
}
--- mm08/arch/ppc/kernel/dma-mapping.c 2005-09-21 12:16:17.000000000 +0100
+++ mm09/arch/ppc/kernel/dma-mapping.c 2005-10-11 23:55:53.000000000 +0100
@@ -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;
}

--- mm08/arch/ppc/mm/4xx_mmu.c 2005-08-29 00:41:01.000000000 +0100
+++ mm09/arch/ppc/mm/4xx_mmu.c 2005-10-11 23:55:54.000000000 +0100
@@ -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;
--- mm08/arch/ppc/mm/pgtable.c 2005-08-29 00:41:01.000000000 +0100
+++ mm09/arch/ppc/mm/pgtable.c 2005-10-11 23:55:54.000000000 +0100
@@ -280,18 +280,16 @@ map_page(unsigned long va, phys_addr_t p
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;
}

--- mm08/arch/ppc64/mm/imalloc.c 2005-09-21 12:16:19.000000000 +0100
+++ mm09/arch/ppc64/mm/imalloc.c 2005-10-11 23:55:54.000000000 +0100
@@ -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;
--- mm08/arch/ppc64/mm/init.c 2005-09-30 11:58:54.000000000 +0100
+++ mm09/arch/ppc64/mm/init.c 2005-10-11 23:55:54.000000000 +0100
@@ -158,7 +158,6 @@ static int map_io_page(unsigned long ea,
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)
@@ -166,12 +165,11 @@ static int map_io_page(unsigned long ea,
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;

--- mm08/arch/s390/mm/ioremap.c 2004-06-16 06:20:37.000000000 +0100
+++ mm09/arch/s390/mm/ioremap.c 2005-10-11 23:55:54.000000000 +0100
@@ -58,7 +58,7 @@ static inline int remap_area_pmd(pmd_t *
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 lon
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 lon
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
flush_tlb_all();
return 0;
}
--- mm08/arch/sh/mm/ioremap.c 2004-12-24 21:37:00.000000000 +0000
+++ mm09/arch/sh/mm/ioremap.c 2005-10-11 23:55:54.000000000 +0100
@@ -57,7 +57,7 @@ static inline int remap_area_pmd(pmd_t *
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 addre
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 addre
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
flush_tlb_all();
return error;
}
--- mm08/arch/sh64/mm/ioremap.c 2005-06-17 20:48:29.000000000 +0100
+++ mm09/arch/sh64/mm/ioremap.c 2005-10-11 23:55:54.000000000 +0100
@@ -79,7 +79,7 @@ static inline int remap_area_pmd(pmd_t *
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 lon
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 lon
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
flush_tlb_all();
return 0;
}
--- mm08/arch/x86_64/mm/ioremap.c 2005-09-30 11:58:56.000000000 +0100
+++ mm09/arch/x86_64/mm/ioremap.c 2005-10-11 23:55:54.000000000 +0100
@@ -60,7 +60,7 @@ static inline int remap_area_pmd(pmd_t *
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 lon
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 lon
address = (address + PGDIR_SIZE) & PGDIR_MASK;
pgd++;
} while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
flush_tlb_all();
return error;
}
--- mm08/include/linux/mm.h 2005-10-11 23:55:38.000000000 +0100
+++ mm09/include/linux/mm.h 2005-10-11 23:55:54.000000000 +0100
@@ -711,7 +711,7 @@ static inline void unmap_shared_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);
--- mm08/mm/memory.c 2005-10-11 23:54:33.000000000 +0100
+++ mm09/mm/memory.c 2005-10-11 23:55:54.000000000 +0100
@@ -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 *
#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_st
#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_st
#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 */
--- mm08/mm/vmalloc.c 2005-09-21 12:16:59.000000000 +0100
+++ mm09/mm/vmalloc.c 2005-10-11 23:55:54.000000000 +0100
@@ -88,7 +88,7 @@ static int vmap_pte_range(pmd_t *pmd, un
{
pte_t *pte;

- pte = pte_alloc_kernel(&init_mm, pmd, addr);
+ pte = pte_alloc_kernel(pmd, addr);
if (!pte)
return -ENOMEM;
do {
@@ -146,14 +146,12 @@ int map_vm_area(struct vm_struct *area,

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;
}
-
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