diff options
Diffstat (limited to 'fs/hugetlbfs/inode.c')
| -rw-r--r-- | fs/hugetlbfs/inode.c | 49 |
1 files changed, 34 insertions, 15 deletions
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index f42548ee9083..3919fca56553 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -96,8 +96,15 @@ static const struct fs_parameter_spec hugetlb_fs_parameters[] = { #define PGOFF_LOFFT_MAX \ (((1UL << (PAGE_SHIFT + 1)) - 1) << (BITS_PER_LONG - (PAGE_SHIFT + 1))) -static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) +static int hugetlb_file_mmap_prepare_success(const struct vm_area_struct *vma) { + /* Unfortunate we have to reassign vma->vm_private_data. */ + return hugetlb_vma_lock_alloc((struct vm_area_struct *)vma); +} + +static int hugetlbfs_file_mmap_prepare(struct vm_area_desc *desc) +{ + struct file *file = desc->file; struct inode *inode = file_inode(file); loff_t len, vma_len; int ret; @@ -112,8 +119,8 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) * way when do_mmap unwinds (may be important on powerpc * and ia64). */ - vm_flags_set(vma, VM_HUGETLB | VM_DONTEXPAND); - vma->vm_ops = &hugetlb_vm_ops; + desc->vm_flags |= VM_HUGETLB | VM_DONTEXPAND; + desc->vm_ops = &hugetlb_vm_ops; /* * page based offset in vm_pgoff could be sufficiently large to @@ -122,16 +129,16 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) * sizeof(unsigned long). So, only check in those instances. */ if (sizeof(unsigned long) == sizeof(loff_t)) { - if (vma->vm_pgoff & PGOFF_LOFFT_MAX) + if (desc->pgoff & PGOFF_LOFFT_MAX) return -EINVAL; } /* must be huge page aligned */ - if (vma->vm_pgoff & (~huge_page_mask(h) >> PAGE_SHIFT)) + if (desc->pgoff & (~huge_page_mask(h) >> PAGE_SHIFT)) return -EINVAL; - vma_len = (loff_t)(vma->vm_end - vma->vm_start); - len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); + vma_len = (loff_t)vma_desc_size(desc); + len = vma_len + ((loff_t)desc->pgoff << PAGE_SHIFT); /* check for overflow */ if (len < vma_len) return -EINVAL; @@ -141,7 +148,7 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) ret = -ENOMEM; - vm_flags = vma->vm_flags; + vm_flags = desc->vm_flags; /* * for SHM_HUGETLB, the pages are reserved in the shmget() call so skip * reserving here. Note: only for SHM hugetlbfs file, the inode @@ -151,17 +158,30 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) vm_flags |= VM_NORESERVE; if (hugetlb_reserve_pages(inode, - vma->vm_pgoff >> huge_page_order(h), - len >> huge_page_shift(h), vma, - vm_flags) < 0) + desc->pgoff >> huge_page_order(h), + len >> huge_page_shift(h), desc, + vm_flags) < 0) goto out; ret = 0; - if (vma->vm_flags & VM_WRITE && inode->i_size < len) + if ((desc->vm_flags & VM_WRITE) && inode->i_size < len) i_size_write(inode, len); out: inode_unlock(inode); + if (!ret) { + /* Allocate the VMA lock after we set it up. */ + desc->action.success_hook = hugetlb_file_mmap_prepare_success; + /* + * We cannot permit the rmap finding this VMA in the time + * between the VMA being inserted into the VMA tree and the + * completion/success hook being invoked. + * + * This is because we establish a per-VMA hugetlb lock which can + * be raced by rmap. + */ + desc->action.hide_from_rmap_until_complete = true; + } return ret; } @@ -184,8 +204,7 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr, if (addr) addr0 = ALIGN(addr, huge_page_size(h)); - return mm_get_unmapped_area_vmflags(current->mm, file, addr0, len, pgoff, - flags, 0); + return mm_get_unmapped_area_vmflags(file, addr0, len, pgoff, flags, 0); } /* @@ -1221,7 +1240,7 @@ static void init_once(void *foo) static const struct file_operations hugetlbfs_file_operations = { .read_iter = hugetlbfs_read_iter, - .mmap = hugetlbfs_file_mmap, + .mmap_prepare = hugetlbfs_file_mmap_prepare, .fsync = noop_fsync, .get_unmapped_area = hugetlb_get_unmapped_area, .llseek = default_llseek, |