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author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2009-03-18 13:27:37 +0100 |
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committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2009-03-18 13:28:13 +0100 |
commit | 0fb1d9bcbcf701a45835aa150c57ca54ea685bfa (patch) | |
tree | a2821e3d10918d4b76e6329da42a45cfbb9f19cd /arch | |
parent | f481bfafd36e621d6cbc62d4b25f74811410aef7 (diff) | |
download | lwn-0fb1d9bcbcf701a45835aa150c57ca54ea685bfa.tar.gz lwn-0fb1d9bcbcf701a45835aa150c57ca54ea685bfa.zip |
[S390] make page table upgrade work again
After TASK_SIZE now gives the current size of the address space the
upgrade of a 64 bit process from 3 to 4 levels of page table needs
to use the arch_mmap_check hook to catch large mmap lengths. The
get_unmapped_area* functions need to check for -ENOMEM from the
arch_get_unmapped_area*, upgrade the page table and retry.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/s390/include/asm/mman.h | 5 | ||||
-rw-r--r-- | arch/s390/mm/mmap.c | 44 |
2 files changed, 35 insertions, 14 deletions
diff --git a/arch/s390/include/asm/mman.h b/arch/s390/include/asm/mman.h index 7839767d837e..da01432e8f44 100644 --- a/arch/s390/include/asm/mman.h +++ b/arch/s390/include/asm/mman.h @@ -22,4 +22,9 @@ #define MCL_CURRENT 1 /* lock all current mappings */ #define MCL_FUTURE 2 /* lock all future mappings */ +#if defined(__KERNEL__) && !defined(__ASSEMBLY__) && defined(CONFIG_64BIT) +int s390_mmap_check(unsigned long addr, unsigned long len); +#define arch_mmap_check(addr,len,flags) s390_mmap_check(addr,len) +#endif + #endif /* __S390_MMAN_H__ */ diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c index 346dd0c5cbde..e008d236cc15 100644 --- a/arch/s390/mm/mmap.c +++ b/arch/s390/mm/mmap.c @@ -89,42 +89,58 @@ EXPORT_SYMBOL_GPL(arch_pick_mmap_layout); #else +int s390_mmap_check(unsigned long addr, unsigned long len) +{ + if (!test_thread_flag(TIF_31BIT) && + len >= TASK_SIZE && TASK_SIZE < (1UL << 53)) + return crst_table_upgrade(current->mm, 1UL << 53); + return 0; +} + static unsigned long s390_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags) { struct mm_struct *mm = current->mm; + unsigned long area; int rc; - addr = arch_get_unmapped_area(filp, addr, len, pgoff, flags); - if (addr & ~PAGE_MASK) - return addr; - if (unlikely(mm->context.asce_limit < addr + len)) { - rc = crst_table_upgrade(mm, addr + len); + area = arch_get_unmapped_area(filp, addr, len, pgoff, flags); + if (!(area & ~PAGE_MASK)) + return area; + if (area == -ENOMEM && + !test_thread_flag(TIF_31BIT) && TASK_SIZE < (1UL << 53)) { + /* Upgrade the page table to 4 levels and retry. */ + rc = crst_table_upgrade(mm, 1UL << 53); if (rc) return (unsigned long) rc; + area = arch_get_unmapped_area(filp, addr, len, pgoff, flags); } - return addr; + return area; } static unsigned long -s390_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, +s390_get_unmapped_area_topdown(struct file *filp, const unsigned long addr, const unsigned long len, const unsigned long pgoff, const unsigned long flags) { struct mm_struct *mm = current->mm; - unsigned long addr = addr0; + unsigned long area; int rc; - addr = arch_get_unmapped_area_topdown(filp, addr, len, pgoff, flags); - if (addr & ~PAGE_MASK) - return addr; - if (unlikely(mm->context.asce_limit < addr + len)) { - rc = crst_table_upgrade(mm, addr + len); + area = arch_get_unmapped_area_topdown(filp, addr, len, pgoff, flags); + if (!(area & ~PAGE_MASK)) + return area; + if (area == -ENOMEM && + !test_thread_flag(TIF_31BIT) && TASK_SIZE < (1UL << 53)) { + /* Upgrade the page table to 4 levels and retry. */ + rc = crst_table_upgrade(mm, 1UL << 53); if (rc) return (unsigned long) rc; + area = arch_get_unmapped_area_topdown(filp, addr, len, + pgoff, flags); } - return addr; + return area; } /* * This function, called very early during the creation of a new |