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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-21 20:36:41 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-21 20:36:41 (GMT) |
commit | e2a0883e4071237d09b604a342c28b96b44a04b3 (patch) | |
tree | aa56f4d376b5eb1c32358c19c2669c2a94e0e1fd /arch/um | |
parent | 3a990a52f9f25f45469e272017a31e7a3fda60ed (diff) | |
parent | 07c0c5d8b8c122b2f2df9ee574ac3083daefc981 (diff) | |
download | linux-e2a0883e4071237d09b604a342c28b96b44a04b3.tar.xz |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile 1 from Al Viro:
"This is _not_ all; in particular, Miklos' and Jan's stuff is not there
yet."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
ext4: initialization of ext4_li_mtx needs to be done earlier
debugfs-related mode_t whack-a-mole
hfsplus: add an ioctl to bless files
hfsplus: change finder_info to u32
hfsplus: initialise userflags
qnx4: new helper - try_extent()
qnx4: get rid of qnx4_bread/qnx4_getblk
take removal of PF_FORKNOEXEC to flush_old_exec()
trim includes in inode.c
um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
um: embed ->stub_pages[] into mmu_context
gadgetfs: list_for_each_safe() misuse
ocfs2: fix leaks on failure exits in module_init
ecryptfs: make register_filesystem() the last potential failure exit
ntfs: forgets to unregister sysctls on register_filesystem() failure
logfs: missing cleanup on register_filesystem() failure
jfs: mising cleanup on register_filesystem() failure
make configfs_pin_fs() return root dentry on success
configfs: configfs_create_dir() has parent dentry in dentry->d_parent
configfs: sanitize configfs_create()
...
Diffstat (limited to 'arch/um')
-rw-r--r-- | arch/um/include/asm/mmu.h | 2 | ||||
-rw-r--r-- | arch/um/include/asm/mmu_context.h | 11 | ||||
-rw-r--r-- | arch/um/kernel/skas/mmu.c | 25 |
3 files changed, 16 insertions, 22 deletions
diff --git a/arch/um/include/asm/mmu.h b/arch/um/include/asm/mmu.h index 30509b9..53e8b49 100644 --- a/arch/um/include/asm/mmu.h +++ b/arch/um/include/asm/mmu.h @@ -12,7 +12,7 @@ typedef struct mm_context { struct mm_id id; struct uml_arch_mm_context arch; - struct page **stub_pages; + struct page *stub_pages[2]; } mm_context_t; extern void __switch_mm(struct mm_id * mm_idp); diff --git a/arch/um/include/asm/mmu_context.h b/arch/um/include/asm/mmu_context.h index 591b3d8..aa4a743 100644 --- a/arch/um/include/asm/mmu_context.h +++ b/arch/um/include/asm/mmu_context.h @@ -9,7 +9,7 @@ #include <linux/sched.h> #include <asm/mmu.h> -extern void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm); +extern void uml_setup_stubs(struct mm_struct *mm); extern void arch_exit_mmap(struct mm_struct *mm); #define deactivate_mm(tsk,mm) do { } while (0) @@ -23,7 +23,9 @@ static inline void activate_mm(struct mm_struct *old, struct mm_struct *new) * when the new ->mm is used for the first time. */ __switch_mm(&new->context.id); - arch_dup_mmap(old, new); + down_write(&new->mmap_sem); + uml_setup_stubs(new); + up_write(&new->mmap_sem); } static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, @@ -39,6 +41,11 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, } } +static inline void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm) +{ + uml_setup_stubs(mm); +} + static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) { diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c index 1aee587..4947b31 100644 --- a/arch/um/kernel/skas/mmu.c +++ b/arch/um/kernel/skas/mmu.c @@ -92,8 +92,6 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm) goto out_free; } - to_mm->stub_pages = NULL; - return 0; out_free: @@ -103,7 +101,7 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm) return ret; } -void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm) +void uml_setup_stubs(struct mm_struct *mm) { struct page **pages; int err, ret; @@ -120,29 +118,20 @@ void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm) if (ret) goto out; - pages = kmalloc(2 * sizeof(struct page *), GFP_KERNEL); - if (pages == NULL) { - printk(KERN_ERR "arch_dup_mmap failed to allocate 2 page " - "pointers\n"); - goto out; - } - - pages[0] = virt_to_page(&__syscall_stub_start); - pages[1] = virt_to_page(mm->context.id.stack); - mm->context.stub_pages = pages; + mm->context.stub_pages[0] = virt_to_page(&__syscall_stub_start); + mm->context.stub_pages[1] = virt_to_page(mm->context.id.stack); /* dup_mmap already holds mmap_sem */ err = install_special_mapping(mm, STUB_START, STUB_END - STUB_START, VM_READ | VM_MAYREAD | VM_EXEC | - VM_MAYEXEC | VM_DONTCOPY, pages); + VM_MAYEXEC | VM_DONTCOPY, + mm->context.stub_pages); if (err) { printk(KERN_ERR "install_special_mapping returned %d\n", err); - goto out_free; + goto out; } return; -out_free: - kfree(pages); out: force_sigsegv(SIGSEGV, current); } @@ -151,8 +140,6 @@ void arch_exit_mmap(struct mm_struct *mm) { pte_t *pte; - if (mm->context.stub_pages != NULL) - kfree(mm->context.stub_pages); pte = virt_to_pte(mm, STUB_CODE); if (pte != NULL) pte_clear(mm, STUB_CODE, pte); |