![Marc-André Lureau](/assets/img/avatar_default.png)
Implements memfd sealing, similar to shmem: - WRITE: deny fallocate(PUNCH_HOLE). mmap() write is denied in memfd_add_seals(). write() doesn't exist for hugetlbfs. - SHRINK: added similar check as shmem_setattr() - GROW: added similar check as shmem_setattr() & shmem_fallocate() Except write() operation that doesn't exist with hugetlbfs, that should make sealing as close as it can be to shmem support. Link: http://lkml.kernel.org/r/20171107122800.25517-5-marcandre.lureau@redhat.com Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1431 lines
36 KiB
C
1431 lines
36 KiB
C
/*
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* hugetlbpage-backed filesystem. Based on ramfs.
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*
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* Nadia Yvette Chambers, 2002
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*
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* Copyright (C) 2002 Linus Torvalds.
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* License: GPL
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/thread_info.h>
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#include <asm/current.h>
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#include <linux/sched/signal.h> /* remove ASAP */
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#include <linux/falloc.h>
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#include <linux/fs.h>
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#include <linux/mount.h>
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#include <linux/file.h>
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#include <linux/kernel.h>
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#include <linux/writeback.h>
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#include <linux/pagemap.h>
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#include <linux/highmem.h>
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#include <linux/init.h>
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#include <linux/string.h>
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#include <linux/capability.h>
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#include <linux/ctype.h>
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#include <linux/backing-dev.h>
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#include <linux/hugetlb.h>
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#include <linux/pagevec.h>
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#include <linux/parser.h>
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#include <linux/mman.h>
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#include <linux/slab.h>
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#include <linux/dnotify.h>
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#include <linux/statfs.h>
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#include <linux/security.h>
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#include <linux/magic.h>
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#include <linux/migrate.h>
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#include <linux/uio.h>
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#include <linux/uaccess.h>
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static const struct super_operations hugetlbfs_ops;
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static const struct address_space_operations hugetlbfs_aops;
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const struct file_operations hugetlbfs_file_operations;
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static const struct inode_operations hugetlbfs_dir_inode_operations;
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static const struct inode_operations hugetlbfs_inode_operations;
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struct hugetlbfs_config {
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struct hstate *hstate;
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long max_hpages;
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long nr_inodes;
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long min_hpages;
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kuid_t uid;
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kgid_t gid;
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umode_t mode;
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};
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int sysctl_hugetlb_shm_group;
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enum {
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Opt_size, Opt_nr_inodes,
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Opt_mode, Opt_uid, Opt_gid,
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Opt_pagesize, Opt_min_size,
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Opt_err,
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};
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static const match_table_t tokens = {
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{Opt_size, "size=%s"},
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{Opt_nr_inodes, "nr_inodes=%s"},
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{Opt_mode, "mode=%o"},
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{Opt_uid, "uid=%u"},
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{Opt_gid, "gid=%u"},
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{Opt_pagesize, "pagesize=%s"},
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{Opt_min_size, "min_size=%s"},
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{Opt_err, NULL},
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};
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#ifdef CONFIG_NUMA
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static inline void hugetlb_set_vma_policy(struct vm_area_struct *vma,
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struct inode *inode, pgoff_t index)
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{
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vma->vm_policy = mpol_shared_policy_lookup(&HUGETLBFS_I(inode)->policy,
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index);
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}
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static inline void hugetlb_drop_vma_policy(struct vm_area_struct *vma)
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{
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mpol_cond_put(vma->vm_policy);
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}
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#else
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static inline void hugetlb_set_vma_policy(struct vm_area_struct *vma,
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struct inode *inode, pgoff_t index)
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{
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}
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static inline void hugetlb_drop_vma_policy(struct vm_area_struct *vma)
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{
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}
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#endif
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static void huge_pagevec_release(struct pagevec *pvec)
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{
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int i;
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for (i = 0; i < pagevec_count(pvec); ++i)
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put_page(pvec->pages[i]);
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pagevec_reinit(pvec);
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}
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static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma)
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{
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struct inode *inode = file_inode(file);
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loff_t len, vma_len;
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int ret;
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struct hstate *h = hstate_file(file);
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/*
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* vma address alignment (but not the pgoff alignment) has
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* already been checked by prepare_hugepage_range. If you add
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* any error returns here, do so after setting VM_HUGETLB, so
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* is_vm_hugetlb_page tests below unmap_region go the right
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* way when do_mmap_pgoff unwinds (may be important on powerpc
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* and ia64).
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*/
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vma->vm_flags |= VM_HUGETLB | VM_DONTEXPAND;
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vma->vm_ops = &hugetlb_vm_ops;
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/*
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* Offset passed to mmap (before page shift) could have been
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* negative when represented as a (l)off_t.
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*/
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if (((loff_t)vma->vm_pgoff << PAGE_SHIFT) < 0)
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return -EINVAL;
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if (vma->vm_pgoff & (~huge_page_mask(h) >> PAGE_SHIFT))
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return -EINVAL;
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vma_len = (loff_t)(vma->vm_end - vma->vm_start);
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len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
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/* check for overflow */
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if (len < vma_len)
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return -EINVAL;
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inode_lock(inode);
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file_accessed(file);
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ret = -ENOMEM;
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if (hugetlb_reserve_pages(inode,
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vma->vm_pgoff >> huge_page_order(h),
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len >> huge_page_shift(h), vma,
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vma->vm_flags))
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goto out;
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ret = 0;
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if (vma->vm_flags & VM_WRITE && inode->i_size < len)
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i_size_write(inode, len);
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out:
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inode_unlock(inode);
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return ret;
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}
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/*
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* Called under down_write(mmap_sem).
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*/
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#ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
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static unsigned long
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hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
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unsigned long len, unsigned long pgoff, unsigned long flags)
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{
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struct mm_struct *mm = current->mm;
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struct vm_area_struct *vma;
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struct hstate *h = hstate_file(file);
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struct vm_unmapped_area_info info;
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if (len & ~huge_page_mask(h))
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return -EINVAL;
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if (len > TASK_SIZE)
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return -ENOMEM;
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if (flags & MAP_FIXED) {
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if (prepare_hugepage_range(file, addr, len))
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return -EINVAL;
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return addr;
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}
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if (addr) {
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addr = ALIGN(addr, huge_page_size(h));
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vma = find_vma(mm, addr);
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if (TASK_SIZE - len >= addr &&
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(!vma || addr + len <= vm_start_gap(vma)))
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return addr;
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}
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info.flags = 0;
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info.length = len;
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info.low_limit = TASK_UNMAPPED_BASE;
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info.high_limit = TASK_SIZE;
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info.align_mask = PAGE_MASK & ~huge_page_mask(h);
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info.align_offset = 0;
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return vm_unmapped_area(&info);
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}
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#endif
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static size_t
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hugetlbfs_read_actor(struct page *page, unsigned long offset,
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struct iov_iter *to, unsigned long size)
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{
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size_t copied = 0;
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int i, chunksize;
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/* Find which 4k chunk and offset with in that chunk */
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i = offset >> PAGE_SHIFT;
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offset = offset & ~PAGE_MASK;
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while (size) {
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size_t n;
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chunksize = PAGE_SIZE;
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if (offset)
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chunksize -= offset;
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if (chunksize > size)
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chunksize = size;
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n = copy_page_to_iter(&page[i], offset, chunksize, to);
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copied += n;
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if (n != chunksize)
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return copied;
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offset = 0;
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size -= chunksize;
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i++;
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}
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return copied;
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}
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/*
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* Support for read() - Find the page attached to f_mapping and copy out the
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* data. Its *very* similar to do_generic_mapping_read(), we can't use that
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* since it has PAGE_SIZE assumptions.
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*/
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static ssize_t hugetlbfs_read_iter(struct kiocb *iocb, struct iov_iter *to)
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{
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struct file *file = iocb->ki_filp;
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struct hstate *h = hstate_file(file);
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struct address_space *mapping = file->f_mapping;
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struct inode *inode = mapping->host;
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unsigned long index = iocb->ki_pos >> huge_page_shift(h);
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unsigned long offset = iocb->ki_pos & ~huge_page_mask(h);
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unsigned long end_index;
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loff_t isize;
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ssize_t retval = 0;
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while (iov_iter_count(to)) {
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struct page *page;
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size_t nr, copied;
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/* nr is the maximum number of bytes to copy from this page */
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nr = huge_page_size(h);
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isize = i_size_read(inode);
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if (!isize)
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break;
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end_index = (isize - 1) >> huge_page_shift(h);
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if (index > end_index)
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break;
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if (index == end_index) {
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nr = ((isize - 1) & ~huge_page_mask(h)) + 1;
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if (nr <= offset)
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break;
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}
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nr = nr - offset;
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/* Find the page */
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page = find_lock_page(mapping, index);
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if (unlikely(page == NULL)) {
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/*
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* We have a HOLE, zero out the user-buffer for the
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* length of the hole or request.
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*/
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copied = iov_iter_zero(nr, to);
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} else {
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unlock_page(page);
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/*
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* We have the page, copy it to user space buffer.
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*/
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copied = hugetlbfs_read_actor(page, offset, to, nr);
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put_page(page);
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}
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offset += copied;
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retval += copied;
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if (copied != nr && iov_iter_count(to)) {
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if (!retval)
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retval = -EFAULT;
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break;
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}
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index += offset >> huge_page_shift(h);
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offset &= ~huge_page_mask(h);
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}
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iocb->ki_pos = ((loff_t)index << huge_page_shift(h)) + offset;
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return retval;
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}
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static int hugetlbfs_write_begin(struct file *file,
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struct address_space *mapping,
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loff_t pos, unsigned len, unsigned flags,
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struct page **pagep, void **fsdata)
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{
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return -EINVAL;
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}
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static int hugetlbfs_write_end(struct file *file, struct address_space *mapping,
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loff_t pos, unsigned len, unsigned copied,
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struct page *page, void *fsdata)
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{
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BUG();
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return -EINVAL;
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}
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static void remove_huge_page(struct page *page)
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{
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ClearPageDirty(page);
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ClearPageUptodate(page);
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delete_from_page_cache(page);
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}
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static void
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hugetlb_vmdelete_list(struct rb_root_cached *root, pgoff_t start, pgoff_t end)
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{
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struct vm_area_struct *vma;
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/*
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* end == 0 indicates that the entire range after
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* start should be unmapped.
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*/
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vma_interval_tree_foreach(vma, root, start, end ? end : ULONG_MAX) {
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unsigned long v_offset;
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unsigned long v_end;
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/*
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* Can the expression below overflow on 32-bit arches?
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* No, because the interval tree returns us only those vmas
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* which overlap the truncated area starting at pgoff,
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* and no vma on a 32-bit arch can span beyond the 4GB.
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*/
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if (vma->vm_pgoff < start)
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v_offset = (start - vma->vm_pgoff) << PAGE_SHIFT;
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else
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v_offset = 0;
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if (!end)
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v_end = vma->vm_end;
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else {
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v_end = ((end - vma->vm_pgoff) << PAGE_SHIFT)
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+ vma->vm_start;
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if (v_end > vma->vm_end)
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v_end = vma->vm_end;
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}
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unmap_hugepage_range(vma, vma->vm_start + v_offset, v_end,
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NULL);
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}
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}
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/*
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* remove_inode_hugepages handles two distinct cases: truncation and hole
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* punch. There are subtle differences in operation for each case.
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*
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* truncation is indicated by end of range being LLONG_MAX
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* In this case, we first scan the range and release found pages.
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* After releasing pages, hugetlb_unreserve_pages cleans up region/reserv
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* maps and global counts. Page faults can not race with truncation
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* in this routine. hugetlb_no_page() prevents page faults in the
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* truncated range. It checks i_size before allocation, and again after
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* with the page table lock for the page held. The same lock must be
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* acquired to unmap a page.
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* hole punch is indicated if end is not LLONG_MAX
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* In the hole punch case we scan the range and release found pages.
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* Only when releasing a page is the associated region/reserv map
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* deleted. The region/reserv map for ranges without associated
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* pages are not modified. Page faults can race with hole punch.
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* This is indicated if we find a mapped page.
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* Note: If the passed end of range value is beyond the end of file, but
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* not LLONG_MAX this routine still performs a hole punch operation.
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*/
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static void remove_inode_hugepages(struct inode *inode, loff_t lstart,
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loff_t lend)
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{
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struct hstate *h = hstate_inode(inode);
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struct address_space *mapping = &inode->i_data;
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const pgoff_t start = lstart >> huge_page_shift(h);
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const pgoff_t end = lend >> huge_page_shift(h);
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struct vm_area_struct pseudo_vma;
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struct pagevec pvec;
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pgoff_t next, index;
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int i, freed = 0;
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bool truncate_op = (lend == LLONG_MAX);
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memset(&pseudo_vma, 0, sizeof(struct vm_area_struct));
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pseudo_vma.vm_flags = (VM_HUGETLB | VM_MAYSHARE | VM_SHARED);
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pagevec_init(&pvec);
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next = start;
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while (next < end) {
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/*
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* When no more pages are found, we are done.
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*/
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if (!pagevec_lookup_range(&pvec, mapping, &next, end - 1))
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break;
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for (i = 0; i < pagevec_count(&pvec); ++i) {
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struct page *page = pvec.pages[i];
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u32 hash;
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index = page->index;
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hash = hugetlb_fault_mutex_hash(h, current->mm,
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&pseudo_vma,
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mapping, index, 0);
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mutex_lock(&hugetlb_fault_mutex_table[hash]);
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/*
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* If page is mapped, it was faulted in after being
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* unmapped in caller. Unmap (again) now after taking
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* the fault mutex. The mutex will prevent faults
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* until we finish removing the page.
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*
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* This race can only happen in the hole punch case.
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* Getting here in a truncate operation is a bug.
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*/
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if (unlikely(page_mapped(page))) {
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BUG_ON(truncate_op);
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i_mmap_lock_write(mapping);
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hugetlb_vmdelete_list(&mapping->i_mmap,
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index * pages_per_huge_page(h),
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(index + 1) * pages_per_huge_page(h));
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i_mmap_unlock_write(mapping);
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}
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lock_page(page);
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/*
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* We must free the huge page and remove from page
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* cache (remove_huge_page) BEFORE removing the
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* region/reserve map (hugetlb_unreserve_pages). In
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* rare out of memory conditions, removal of the
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* region/reserve map could fail. Correspondingly,
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* the subpool and global reserve usage count can need
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* to be adjusted.
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*/
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VM_BUG_ON(PagePrivate(page));
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remove_huge_page(page);
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freed++;
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if (!truncate_op) {
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if (unlikely(hugetlb_unreserve_pages(inode,
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index, index + 1, 1)))
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hugetlb_fix_reserve_counts(inode);
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}
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unlock_page(page);
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mutex_unlock(&hugetlb_fault_mutex_table[hash]);
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}
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huge_pagevec_release(&pvec);
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cond_resched();
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}
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if (truncate_op)
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(void)hugetlb_unreserve_pages(inode, start, LONG_MAX, freed);
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}
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|
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static void hugetlbfs_evict_inode(struct inode *inode)
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{
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struct resv_map *resv_map;
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remove_inode_hugepages(inode, 0, LLONG_MAX);
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resv_map = (struct resv_map *)inode->i_mapping->private_data;
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/* root inode doesn't have the resv_map, so we should check it */
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if (resv_map)
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resv_map_release(&resv_map->refs);
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clear_inode(inode);
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}
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static int hugetlb_vmtruncate(struct inode *inode, loff_t offset)
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{
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pgoff_t pgoff;
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struct address_space *mapping = inode->i_mapping;
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struct hstate *h = hstate_inode(inode);
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BUG_ON(offset & ~huge_page_mask(h));
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pgoff = offset >> PAGE_SHIFT;
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|
|
i_size_write(inode, offset);
|
|
i_mmap_lock_write(mapping);
|
|
if (!RB_EMPTY_ROOT(&mapping->i_mmap.rb_root))
|
|
hugetlb_vmdelete_list(&mapping->i_mmap, pgoff, 0);
|
|
i_mmap_unlock_write(mapping);
|
|
remove_inode_hugepages(inode, offset, LLONG_MAX);
|
|
return 0;
|
|
}
|
|
|
|
static long hugetlbfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
|
|
{
|
|
struct hstate *h = hstate_inode(inode);
|
|
loff_t hpage_size = huge_page_size(h);
|
|
loff_t hole_start, hole_end;
|
|
|
|
/*
|
|
* For hole punch round up the beginning offset of the hole and
|
|
* round down the end.
|
|
*/
|
|
hole_start = round_up(offset, hpage_size);
|
|
hole_end = round_down(offset + len, hpage_size);
|
|
|
|
if (hole_end > hole_start) {
|
|
struct address_space *mapping = inode->i_mapping;
|
|
struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode);
|
|
|
|
inode_lock(inode);
|
|
|
|
/* protected by i_mutex */
|
|
if (info->seals & F_SEAL_WRITE) {
|
|
inode_unlock(inode);
|
|
return -EPERM;
|
|
}
|
|
|
|
i_mmap_lock_write(mapping);
|
|
if (!RB_EMPTY_ROOT(&mapping->i_mmap.rb_root))
|
|
hugetlb_vmdelete_list(&mapping->i_mmap,
|
|
hole_start >> PAGE_SHIFT,
|
|
hole_end >> PAGE_SHIFT);
|
|
i_mmap_unlock_write(mapping);
|
|
remove_inode_hugepages(inode, hole_start, hole_end);
|
|
inode_unlock(inode);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,
|
|
loff_t len)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode);
|
|
struct address_space *mapping = inode->i_mapping;
|
|
struct hstate *h = hstate_inode(inode);
|
|
struct vm_area_struct pseudo_vma;
|
|
struct mm_struct *mm = current->mm;
|
|
loff_t hpage_size = huge_page_size(h);
|
|
unsigned long hpage_shift = huge_page_shift(h);
|
|
pgoff_t start, index, end;
|
|
int error;
|
|
u32 hash;
|
|
|
|
if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (mode & FALLOC_FL_PUNCH_HOLE)
|
|
return hugetlbfs_punch_hole(inode, offset, len);
|
|
|
|
/*
|
|
* Default preallocate case.
|
|
* For this range, start is rounded down and end is rounded up
|
|
* as well as being converted to page offsets.
|
|
*/
|
|
start = offset >> hpage_shift;
|
|
end = (offset + len + hpage_size - 1) >> hpage_shift;
|
|
|
|
inode_lock(inode);
|
|
|
|
/* We need to check rlimit even when FALLOC_FL_KEEP_SIZE */
|
|
error = inode_newsize_ok(inode, offset + len);
|
|
if (error)
|
|
goto out;
|
|
|
|
if ((info->seals & F_SEAL_GROW) && offset + len > inode->i_size) {
|
|
error = -EPERM;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Initialize a pseudo vma as this is required by the huge page
|
|
* allocation routines. If NUMA is configured, use page index
|
|
* as input to create an allocation policy.
|
|
*/
|
|
memset(&pseudo_vma, 0, sizeof(struct vm_area_struct));
|
|
pseudo_vma.vm_flags = (VM_HUGETLB | VM_MAYSHARE | VM_SHARED);
|
|
pseudo_vma.vm_file = file;
|
|
|
|
for (index = start; index < end; index++) {
|
|
/*
|
|
* This is supposed to be the vaddr where the page is being
|
|
* faulted in, but we have no vaddr here.
|
|
*/
|
|
struct page *page;
|
|
unsigned long addr;
|
|
int avoid_reserve = 0;
|
|
|
|
cond_resched();
|
|
|
|
/*
|
|
* fallocate(2) manpage permits EINTR; we may have been
|
|
* interrupted because we are using up too much memory.
|
|
*/
|
|
if (signal_pending(current)) {
|
|
error = -EINTR;
|
|
break;
|
|
}
|
|
|
|
/* Set numa allocation policy based on index */
|
|
hugetlb_set_vma_policy(&pseudo_vma, inode, index);
|
|
|
|
/* addr is the offset within the file (zero based) */
|
|
addr = index * hpage_size;
|
|
|
|
/* mutex taken here, fault path and hole punch */
|
|
hash = hugetlb_fault_mutex_hash(h, mm, &pseudo_vma, mapping,
|
|
index, addr);
|
|
mutex_lock(&hugetlb_fault_mutex_table[hash]);
|
|
|
|
/* See if already present in mapping to avoid alloc/free */
|
|
page = find_get_page(mapping, index);
|
|
if (page) {
|
|
put_page(page);
|
|
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
|
|
hugetlb_drop_vma_policy(&pseudo_vma);
|
|
continue;
|
|
}
|
|
|
|
/* Allocate page and add to page cache */
|
|
page = alloc_huge_page(&pseudo_vma, addr, avoid_reserve);
|
|
hugetlb_drop_vma_policy(&pseudo_vma);
|
|
if (IS_ERR(page)) {
|
|
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
|
|
error = PTR_ERR(page);
|
|
goto out;
|
|
}
|
|
clear_huge_page(page, addr, pages_per_huge_page(h));
|
|
__SetPageUptodate(page);
|
|
error = huge_add_to_page_cache(page, mapping, index);
|
|
if (unlikely(error)) {
|
|
put_page(page);
|
|
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
|
|
goto out;
|
|
}
|
|
|
|
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
|
|
|
|
/*
|
|
* unlock_page because locked by add_to_page_cache()
|
|
* page_put due to reference from alloc_huge_page()
|
|
*/
|
|
unlock_page(page);
|
|
put_page(page);
|
|
}
|
|
|
|
if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + len > inode->i_size)
|
|
i_size_write(inode, offset + len);
|
|
inode->i_ctime = current_time(inode);
|
|
out:
|
|
inode_unlock(inode);
|
|
return error;
|
|
}
|
|
|
|
static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr)
|
|
{
|
|
struct inode *inode = d_inode(dentry);
|
|
struct hstate *h = hstate_inode(inode);
|
|
int error;
|
|
unsigned int ia_valid = attr->ia_valid;
|
|
struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode);
|
|
|
|
BUG_ON(!inode);
|
|
|
|
error = setattr_prepare(dentry, attr);
|
|
if (error)
|
|
return error;
|
|
|
|
if (ia_valid & ATTR_SIZE) {
|
|
loff_t oldsize = inode->i_size;
|
|
loff_t newsize = attr->ia_size;
|
|
|
|
if (newsize & ~huge_page_mask(h))
|
|
return -EINVAL;
|
|
/* protected by i_mutex */
|
|
if ((newsize < oldsize && (info->seals & F_SEAL_SHRINK)) ||
|
|
(newsize > oldsize && (info->seals & F_SEAL_GROW)))
|
|
return -EPERM;
|
|
error = hugetlb_vmtruncate(inode, newsize);
|
|
if (error)
|
|
return error;
|
|
}
|
|
|
|
setattr_copy(inode, attr);
|
|
mark_inode_dirty(inode);
|
|
return 0;
|
|
}
|
|
|
|
static struct inode *hugetlbfs_get_root(struct super_block *sb,
|
|
struct hugetlbfs_config *config)
|
|
{
|
|
struct inode *inode;
|
|
|
|
inode = new_inode(sb);
|
|
if (inode) {
|
|
inode->i_ino = get_next_ino();
|
|
inode->i_mode = S_IFDIR | config->mode;
|
|
inode->i_uid = config->uid;
|
|
inode->i_gid = config->gid;
|
|
inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
|
|
inode->i_op = &hugetlbfs_dir_inode_operations;
|
|
inode->i_fop = &simple_dir_operations;
|
|
/* directory inodes start off with i_nlink == 2 (for "." entry) */
|
|
inc_nlink(inode);
|
|
lockdep_annotate_inode_mutex_key(inode);
|
|
}
|
|
return inode;
|
|
}
|
|
|
|
/*
|
|
* Hugetlbfs is not reclaimable; therefore its i_mmap_rwsem will never
|
|
* be taken from reclaim -- unlike regular filesystems. This needs an
|
|
* annotation because huge_pmd_share() does an allocation under hugetlb's
|
|
* i_mmap_rwsem.
|
|
*/
|
|
static struct lock_class_key hugetlbfs_i_mmap_rwsem_key;
|
|
|
|
static struct inode *hugetlbfs_get_inode(struct super_block *sb,
|
|
struct inode *dir,
|
|
umode_t mode, dev_t dev)
|
|
{
|
|
struct inode *inode;
|
|
struct resv_map *resv_map;
|
|
|
|
resv_map = resv_map_alloc();
|
|
if (!resv_map)
|
|
return NULL;
|
|
|
|
inode = new_inode(sb);
|
|
if (inode) {
|
|
struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode);
|
|
|
|
inode->i_ino = get_next_ino();
|
|
inode_init_owner(inode, dir, mode);
|
|
lockdep_set_class(&inode->i_mapping->i_mmap_rwsem,
|
|
&hugetlbfs_i_mmap_rwsem_key);
|
|
inode->i_mapping->a_ops = &hugetlbfs_aops;
|
|
inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
|
|
inode->i_mapping->private_data = resv_map;
|
|
info->seals = F_SEAL_SEAL;
|
|
switch (mode & S_IFMT) {
|
|
default:
|
|
init_special_inode(inode, mode, dev);
|
|
break;
|
|
case S_IFREG:
|
|
inode->i_op = &hugetlbfs_inode_operations;
|
|
inode->i_fop = &hugetlbfs_file_operations;
|
|
break;
|
|
case S_IFDIR:
|
|
inode->i_op = &hugetlbfs_dir_inode_operations;
|
|
inode->i_fop = &simple_dir_operations;
|
|
|
|
/* directory inodes start off with i_nlink == 2 (for "." entry) */
|
|
inc_nlink(inode);
|
|
break;
|
|
case S_IFLNK:
|
|
inode->i_op = &page_symlink_inode_operations;
|
|
inode_nohighmem(inode);
|
|
break;
|
|
}
|
|
lockdep_annotate_inode_mutex_key(inode);
|
|
} else
|
|
kref_put(&resv_map->refs, resv_map_release);
|
|
|
|
return inode;
|
|
}
|
|
|
|
/*
|
|
* File creation. Allocate an inode, and we're done..
|
|
*/
|
|
static int hugetlbfs_mknod(struct inode *dir,
|
|
struct dentry *dentry, umode_t mode, dev_t dev)
|
|
{
|
|
struct inode *inode;
|
|
int error = -ENOSPC;
|
|
|
|
inode = hugetlbfs_get_inode(dir->i_sb, dir, mode, dev);
|
|
if (inode) {
|
|
dir->i_ctime = dir->i_mtime = current_time(dir);
|
|
d_instantiate(dentry, inode);
|
|
dget(dentry); /* Extra count - pin the dentry in core */
|
|
error = 0;
|
|
}
|
|
return error;
|
|
}
|
|
|
|
static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
|
|
{
|
|
int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0);
|
|
if (!retval)
|
|
inc_nlink(dir);
|
|
return retval;
|
|
}
|
|
|
|
static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
|
|
{
|
|
return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0);
|
|
}
|
|
|
|
static int hugetlbfs_symlink(struct inode *dir,
|
|
struct dentry *dentry, const char *symname)
|
|
{
|
|
struct inode *inode;
|
|
int error = -ENOSPC;
|
|
|
|
inode = hugetlbfs_get_inode(dir->i_sb, dir, S_IFLNK|S_IRWXUGO, 0);
|
|
if (inode) {
|
|
int l = strlen(symname)+1;
|
|
error = page_symlink(inode, symname, l);
|
|
if (!error) {
|
|
d_instantiate(dentry, inode);
|
|
dget(dentry);
|
|
} else
|
|
iput(inode);
|
|
}
|
|
dir->i_ctime = dir->i_mtime = current_time(dir);
|
|
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* mark the head page dirty
|
|
*/
|
|
static int hugetlbfs_set_page_dirty(struct page *page)
|
|
{
|
|
struct page *head = compound_head(page);
|
|
|
|
SetPageDirty(head);
|
|
return 0;
|
|
}
|
|
|
|
static int hugetlbfs_migrate_page(struct address_space *mapping,
|
|
struct page *newpage, struct page *page,
|
|
enum migrate_mode mode)
|
|
{
|
|
int rc;
|
|
|
|
rc = migrate_huge_page_move_mapping(mapping, newpage, page);
|
|
if (rc != MIGRATEPAGE_SUCCESS)
|
|
return rc;
|
|
if (mode != MIGRATE_SYNC_NO_COPY)
|
|
migrate_page_copy(newpage, page);
|
|
else
|
|
migrate_page_states(newpage, page);
|
|
|
|
return MIGRATEPAGE_SUCCESS;
|
|
}
|
|
|
|
static int hugetlbfs_error_remove_page(struct address_space *mapping,
|
|
struct page *page)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
pgoff_t index = page->index;
|
|
|
|
remove_huge_page(page);
|
|
if (unlikely(hugetlb_unreserve_pages(inode, index, index + 1, 1)))
|
|
hugetlb_fix_reserve_counts(inode);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Display the mount options in /proc/mounts.
|
|
*/
|
|
static int hugetlbfs_show_options(struct seq_file *m, struct dentry *root)
|
|
{
|
|
struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(root->d_sb);
|
|
struct hugepage_subpool *spool = sbinfo->spool;
|
|
unsigned long hpage_size = huge_page_size(sbinfo->hstate);
|
|
unsigned hpage_shift = huge_page_shift(sbinfo->hstate);
|
|
char mod;
|
|
|
|
if (!uid_eq(sbinfo->uid, GLOBAL_ROOT_UID))
|
|
seq_printf(m, ",uid=%u",
|
|
from_kuid_munged(&init_user_ns, sbinfo->uid));
|
|
if (!gid_eq(sbinfo->gid, GLOBAL_ROOT_GID))
|
|
seq_printf(m, ",gid=%u",
|
|
from_kgid_munged(&init_user_ns, sbinfo->gid));
|
|
if (sbinfo->mode != 0755)
|
|
seq_printf(m, ",mode=%o", sbinfo->mode);
|
|
if (sbinfo->max_inodes != -1)
|
|
seq_printf(m, ",nr_inodes=%lu", sbinfo->max_inodes);
|
|
|
|
hpage_size /= 1024;
|
|
mod = 'K';
|
|
if (hpage_size >= 1024) {
|
|
hpage_size /= 1024;
|
|
mod = 'M';
|
|
}
|
|
seq_printf(m, ",pagesize=%lu%c", hpage_size, mod);
|
|
if (spool) {
|
|
if (spool->max_hpages != -1)
|
|
seq_printf(m, ",size=%llu",
|
|
(unsigned long long)spool->max_hpages << hpage_shift);
|
|
if (spool->min_hpages != -1)
|
|
seq_printf(m, ",min_size=%llu",
|
|
(unsigned long long)spool->min_hpages << hpage_shift);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int hugetlbfs_statfs(struct dentry *dentry, struct kstatfs *buf)
|
|
{
|
|
struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(dentry->d_sb);
|
|
struct hstate *h = hstate_inode(d_inode(dentry));
|
|
|
|
buf->f_type = HUGETLBFS_MAGIC;
|
|
buf->f_bsize = huge_page_size(h);
|
|
if (sbinfo) {
|
|
spin_lock(&sbinfo->stat_lock);
|
|
/* If no limits set, just report 0 for max/free/used
|
|
* blocks, like simple_statfs() */
|
|
if (sbinfo->spool) {
|
|
long free_pages;
|
|
|
|
spin_lock(&sbinfo->spool->lock);
|
|
buf->f_blocks = sbinfo->spool->max_hpages;
|
|
free_pages = sbinfo->spool->max_hpages
|
|
- sbinfo->spool->used_hpages;
|
|
buf->f_bavail = buf->f_bfree = free_pages;
|
|
spin_unlock(&sbinfo->spool->lock);
|
|
buf->f_files = sbinfo->max_inodes;
|
|
buf->f_ffree = sbinfo->free_inodes;
|
|
}
|
|
spin_unlock(&sbinfo->stat_lock);
|
|
}
|
|
buf->f_namelen = NAME_MAX;
|
|
return 0;
|
|
}
|
|
|
|
static void hugetlbfs_put_super(struct super_block *sb)
|
|
{
|
|
struct hugetlbfs_sb_info *sbi = HUGETLBFS_SB(sb);
|
|
|
|
if (sbi) {
|
|
sb->s_fs_info = NULL;
|
|
|
|
if (sbi->spool)
|
|
hugepage_put_subpool(sbi->spool);
|
|
|
|
kfree(sbi);
|
|
}
|
|
}
|
|
|
|
static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info *sbinfo)
|
|
{
|
|
if (sbinfo->free_inodes >= 0) {
|
|
spin_lock(&sbinfo->stat_lock);
|
|
if (unlikely(!sbinfo->free_inodes)) {
|
|
spin_unlock(&sbinfo->stat_lock);
|
|
return 0;
|
|
}
|
|
sbinfo->free_inodes--;
|
|
spin_unlock(&sbinfo->stat_lock);
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info *sbinfo)
|
|
{
|
|
if (sbinfo->free_inodes >= 0) {
|
|
spin_lock(&sbinfo->stat_lock);
|
|
sbinfo->free_inodes++;
|
|
spin_unlock(&sbinfo->stat_lock);
|
|
}
|
|
}
|
|
|
|
|
|
static struct kmem_cache *hugetlbfs_inode_cachep;
|
|
|
|
static struct inode *hugetlbfs_alloc_inode(struct super_block *sb)
|
|
{
|
|
struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb);
|
|
struct hugetlbfs_inode_info *p;
|
|
|
|
if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo)))
|
|
return NULL;
|
|
p = kmem_cache_alloc(hugetlbfs_inode_cachep, GFP_KERNEL);
|
|
if (unlikely(!p)) {
|
|
hugetlbfs_inc_free_inodes(sbinfo);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Any time after allocation, hugetlbfs_destroy_inode can be called
|
|
* for the inode. mpol_free_shared_policy is unconditionally called
|
|
* as part of hugetlbfs_destroy_inode. So, initialize policy here
|
|
* in case of a quick call to destroy.
|
|
*
|
|
* Note that the policy is initialized even if we are creating a
|
|
* private inode. This simplifies hugetlbfs_destroy_inode.
|
|
*/
|
|
mpol_shared_policy_init(&p->policy, NULL);
|
|
|
|
return &p->vfs_inode;
|
|
}
|
|
|
|
static void hugetlbfs_i_callback(struct rcu_head *head)
|
|
{
|
|
struct inode *inode = container_of(head, struct inode, i_rcu);
|
|
kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode));
|
|
}
|
|
|
|
static void hugetlbfs_destroy_inode(struct inode *inode)
|
|
{
|
|
hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode->i_sb));
|
|
mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy);
|
|
call_rcu(&inode->i_rcu, hugetlbfs_i_callback);
|
|
}
|
|
|
|
static const struct address_space_operations hugetlbfs_aops = {
|
|
.write_begin = hugetlbfs_write_begin,
|
|
.write_end = hugetlbfs_write_end,
|
|
.set_page_dirty = hugetlbfs_set_page_dirty,
|
|
.migratepage = hugetlbfs_migrate_page,
|
|
.error_remove_page = hugetlbfs_error_remove_page,
|
|
};
|
|
|
|
|
|
static void init_once(void *foo)
|
|
{
|
|
struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo;
|
|
|
|
inode_init_once(&ei->vfs_inode);
|
|
}
|
|
|
|
const struct file_operations hugetlbfs_file_operations = {
|
|
.read_iter = hugetlbfs_read_iter,
|
|
.mmap = hugetlbfs_file_mmap,
|
|
.fsync = noop_fsync,
|
|
.get_unmapped_area = hugetlb_get_unmapped_area,
|
|
.llseek = default_llseek,
|
|
.fallocate = hugetlbfs_fallocate,
|
|
};
|
|
|
|
static const struct inode_operations hugetlbfs_dir_inode_operations = {
|
|
.create = hugetlbfs_create,
|
|
.lookup = simple_lookup,
|
|
.link = simple_link,
|
|
.unlink = simple_unlink,
|
|
.symlink = hugetlbfs_symlink,
|
|
.mkdir = hugetlbfs_mkdir,
|
|
.rmdir = simple_rmdir,
|
|
.mknod = hugetlbfs_mknod,
|
|
.rename = simple_rename,
|
|
.setattr = hugetlbfs_setattr,
|
|
};
|
|
|
|
static const struct inode_operations hugetlbfs_inode_operations = {
|
|
.setattr = hugetlbfs_setattr,
|
|
};
|
|
|
|
static const struct super_operations hugetlbfs_ops = {
|
|
.alloc_inode = hugetlbfs_alloc_inode,
|
|
.destroy_inode = hugetlbfs_destroy_inode,
|
|
.evict_inode = hugetlbfs_evict_inode,
|
|
.statfs = hugetlbfs_statfs,
|
|
.put_super = hugetlbfs_put_super,
|
|
.show_options = hugetlbfs_show_options,
|
|
};
|
|
|
|
enum hugetlbfs_size_type { NO_SIZE, SIZE_STD, SIZE_PERCENT };
|
|
|
|
/*
|
|
* Convert size option passed from command line to number of huge pages
|
|
* in the pool specified by hstate. Size option could be in bytes
|
|
* (val_type == SIZE_STD) or percentage of the pool (val_type == SIZE_PERCENT).
|
|
*/
|
|
static long
|
|
hugetlbfs_size_to_hpages(struct hstate *h, unsigned long long size_opt,
|
|
enum hugetlbfs_size_type val_type)
|
|
{
|
|
if (val_type == NO_SIZE)
|
|
return -1;
|
|
|
|
if (val_type == SIZE_PERCENT) {
|
|
size_opt <<= huge_page_shift(h);
|
|
size_opt *= h->max_huge_pages;
|
|
do_div(size_opt, 100);
|
|
}
|
|
|
|
size_opt >>= huge_page_shift(h);
|
|
return size_opt;
|
|
}
|
|
|
|
static int
|
|
hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig)
|
|
{
|
|
char *p, *rest;
|
|
substring_t args[MAX_OPT_ARGS];
|
|
int option;
|
|
unsigned long long max_size_opt = 0, min_size_opt = 0;
|
|
enum hugetlbfs_size_type max_val_type = NO_SIZE, min_val_type = NO_SIZE;
|
|
|
|
if (!options)
|
|
return 0;
|
|
|
|
while ((p = strsep(&options, ",")) != NULL) {
|
|
int token;
|
|
if (!*p)
|
|
continue;
|
|
|
|
token = match_token(p, tokens, args);
|
|
switch (token) {
|
|
case Opt_uid:
|
|
if (match_int(&args[0], &option))
|
|
goto bad_val;
|
|
pconfig->uid = make_kuid(current_user_ns(), option);
|
|
if (!uid_valid(pconfig->uid))
|
|
goto bad_val;
|
|
break;
|
|
|
|
case Opt_gid:
|
|
if (match_int(&args[0], &option))
|
|
goto bad_val;
|
|
pconfig->gid = make_kgid(current_user_ns(), option);
|
|
if (!gid_valid(pconfig->gid))
|
|
goto bad_val;
|
|
break;
|
|
|
|
case Opt_mode:
|
|
if (match_octal(&args[0], &option))
|
|
goto bad_val;
|
|
pconfig->mode = option & 01777U;
|
|
break;
|
|
|
|
case Opt_size: {
|
|
/* memparse() will accept a K/M/G without a digit */
|
|
if (!isdigit(*args[0].from))
|
|
goto bad_val;
|
|
max_size_opt = memparse(args[0].from, &rest);
|
|
max_val_type = SIZE_STD;
|
|
if (*rest == '%')
|
|
max_val_type = SIZE_PERCENT;
|
|
break;
|
|
}
|
|
|
|
case Opt_nr_inodes:
|
|
/* memparse() will accept a K/M/G without a digit */
|
|
if (!isdigit(*args[0].from))
|
|
goto bad_val;
|
|
pconfig->nr_inodes = memparse(args[0].from, &rest);
|
|
break;
|
|
|
|
case Opt_pagesize: {
|
|
unsigned long ps;
|
|
ps = memparse(args[0].from, &rest);
|
|
pconfig->hstate = size_to_hstate(ps);
|
|
if (!pconfig->hstate) {
|
|
pr_err("Unsupported page size %lu MB\n",
|
|
ps >> 20);
|
|
return -EINVAL;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case Opt_min_size: {
|
|
/* memparse() will accept a K/M/G without a digit */
|
|
if (!isdigit(*args[0].from))
|
|
goto bad_val;
|
|
min_size_opt = memparse(args[0].from, &rest);
|
|
min_val_type = SIZE_STD;
|
|
if (*rest == '%')
|
|
min_val_type = SIZE_PERCENT;
|
|
break;
|
|
}
|
|
|
|
default:
|
|
pr_err("Bad mount option: \"%s\"\n", p);
|
|
return -EINVAL;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Use huge page pool size (in hstate) to convert the size
|
|
* options to number of huge pages. If NO_SIZE, -1 is returned.
|
|
*/
|
|
pconfig->max_hpages = hugetlbfs_size_to_hpages(pconfig->hstate,
|
|
max_size_opt, max_val_type);
|
|
pconfig->min_hpages = hugetlbfs_size_to_hpages(pconfig->hstate,
|
|
min_size_opt, min_val_type);
|
|
|
|
/*
|
|
* If max_size was specified, then min_size must be smaller
|
|
*/
|
|
if (max_val_type > NO_SIZE &&
|
|
pconfig->min_hpages > pconfig->max_hpages) {
|
|
pr_err("minimum size can not be greater than maximum size\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
|
|
bad_val:
|
|
pr_err("Bad value '%s' for mount option '%s'\n", args[0].from, p);
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int
|
|
hugetlbfs_fill_super(struct super_block *sb, void *data, int silent)
|
|
{
|
|
int ret;
|
|
struct hugetlbfs_config config;
|
|
struct hugetlbfs_sb_info *sbinfo;
|
|
|
|
config.max_hpages = -1; /* No limit on size by default */
|
|
config.nr_inodes = -1; /* No limit on number of inodes by default */
|
|
config.uid = current_fsuid();
|
|
config.gid = current_fsgid();
|
|
config.mode = 0755;
|
|
config.hstate = &default_hstate;
|
|
config.min_hpages = -1; /* No default minimum size */
|
|
ret = hugetlbfs_parse_options(data, &config);
|
|
if (ret)
|
|
return ret;
|
|
|
|
sbinfo = kmalloc(sizeof(struct hugetlbfs_sb_info), GFP_KERNEL);
|
|
if (!sbinfo)
|
|
return -ENOMEM;
|
|
sb->s_fs_info = sbinfo;
|
|
sbinfo->hstate = config.hstate;
|
|
spin_lock_init(&sbinfo->stat_lock);
|
|
sbinfo->max_inodes = config.nr_inodes;
|
|
sbinfo->free_inodes = config.nr_inodes;
|
|
sbinfo->spool = NULL;
|
|
sbinfo->uid = config.uid;
|
|
sbinfo->gid = config.gid;
|
|
sbinfo->mode = config.mode;
|
|
|
|
/*
|
|
* Allocate and initialize subpool if maximum or minimum size is
|
|
* specified. Any needed reservations (for minimim size) are taken
|
|
* taken when the subpool is created.
|
|
*/
|
|
if (config.max_hpages != -1 || config.min_hpages != -1) {
|
|
sbinfo->spool = hugepage_new_subpool(config.hstate,
|
|
config.max_hpages,
|
|
config.min_hpages);
|
|
if (!sbinfo->spool)
|
|
goto out_free;
|
|
}
|
|
sb->s_maxbytes = MAX_LFS_FILESIZE;
|
|
sb->s_blocksize = huge_page_size(config.hstate);
|
|
sb->s_blocksize_bits = huge_page_shift(config.hstate);
|
|
sb->s_magic = HUGETLBFS_MAGIC;
|
|
sb->s_op = &hugetlbfs_ops;
|
|
sb->s_time_gran = 1;
|
|
sb->s_root = d_make_root(hugetlbfs_get_root(sb, &config));
|
|
if (!sb->s_root)
|
|
goto out_free;
|
|
return 0;
|
|
out_free:
|
|
kfree(sbinfo->spool);
|
|
kfree(sbinfo);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static struct dentry *hugetlbfs_mount(struct file_system_type *fs_type,
|
|
int flags, const char *dev_name, void *data)
|
|
{
|
|
return mount_nodev(fs_type, flags, data, hugetlbfs_fill_super);
|
|
}
|
|
|
|
static struct file_system_type hugetlbfs_fs_type = {
|
|
.name = "hugetlbfs",
|
|
.mount = hugetlbfs_mount,
|
|
.kill_sb = kill_litter_super,
|
|
};
|
|
|
|
static struct vfsmount *hugetlbfs_vfsmount[HUGE_MAX_HSTATE];
|
|
|
|
static int can_do_hugetlb_shm(void)
|
|
{
|
|
kgid_t shm_group;
|
|
shm_group = make_kgid(&init_user_ns, sysctl_hugetlb_shm_group);
|
|
return capable(CAP_IPC_LOCK) || in_group_p(shm_group);
|
|
}
|
|
|
|
static int get_hstate_idx(int page_size_log)
|
|
{
|
|
struct hstate *h = hstate_sizelog(page_size_log);
|
|
|
|
if (!h)
|
|
return -1;
|
|
return h - hstates;
|
|
}
|
|
|
|
static const struct dentry_operations anon_ops = {
|
|
.d_dname = simple_dname
|
|
};
|
|
|
|
/*
|
|
* Note that size should be aligned to proper hugepage size in caller side,
|
|
* otherwise hugetlb_reserve_pages reserves one less hugepages than intended.
|
|
*/
|
|
struct file *hugetlb_file_setup(const char *name, size_t size,
|
|
vm_flags_t acctflag, struct user_struct **user,
|
|
int creat_flags, int page_size_log)
|
|
{
|
|
struct file *file = ERR_PTR(-ENOMEM);
|
|
struct inode *inode;
|
|
struct path path;
|
|
struct super_block *sb;
|
|
struct qstr quick_string;
|
|
int hstate_idx;
|
|
|
|
hstate_idx = get_hstate_idx(page_size_log);
|
|
if (hstate_idx < 0)
|
|
return ERR_PTR(-ENODEV);
|
|
|
|
*user = NULL;
|
|
if (!hugetlbfs_vfsmount[hstate_idx])
|
|
return ERR_PTR(-ENOENT);
|
|
|
|
if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) {
|
|
*user = current_user();
|
|
if (user_shm_lock(size, *user)) {
|
|
task_lock(current);
|
|
pr_warn_once("%s (%d): Using mlock ulimits for SHM_HUGETLB is deprecated\n",
|
|
current->comm, current->pid);
|
|
task_unlock(current);
|
|
} else {
|
|
*user = NULL;
|
|
return ERR_PTR(-EPERM);
|
|
}
|
|
}
|
|
|
|
sb = hugetlbfs_vfsmount[hstate_idx]->mnt_sb;
|
|
quick_string.name = name;
|
|
quick_string.len = strlen(quick_string.name);
|
|
quick_string.hash = 0;
|
|
path.dentry = d_alloc_pseudo(sb, &quick_string);
|
|
if (!path.dentry)
|
|
goto out_shm_unlock;
|
|
|
|
d_set_d_op(path.dentry, &anon_ops);
|
|
path.mnt = mntget(hugetlbfs_vfsmount[hstate_idx]);
|
|
file = ERR_PTR(-ENOSPC);
|
|
inode = hugetlbfs_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0);
|
|
if (!inode)
|
|
goto out_dentry;
|
|
if (creat_flags == HUGETLB_SHMFS_INODE)
|
|
inode->i_flags |= S_PRIVATE;
|
|
|
|
file = ERR_PTR(-ENOMEM);
|
|
if (hugetlb_reserve_pages(inode, 0,
|
|
size >> huge_page_shift(hstate_inode(inode)), NULL,
|
|
acctflag))
|
|
goto out_inode;
|
|
|
|
d_instantiate(path.dentry, inode);
|
|
inode->i_size = size;
|
|
clear_nlink(inode);
|
|
|
|
file = alloc_file(&path, FMODE_WRITE | FMODE_READ,
|
|
&hugetlbfs_file_operations);
|
|
if (IS_ERR(file))
|
|
goto out_dentry; /* inode is already attached */
|
|
|
|
return file;
|
|
|
|
out_inode:
|
|
iput(inode);
|
|
out_dentry:
|
|
path_put(&path);
|
|
out_shm_unlock:
|
|
if (*user) {
|
|
user_shm_unlock(size, *user);
|
|
*user = NULL;
|
|
}
|
|
return file;
|
|
}
|
|
|
|
static int __init init_hugetlbfs_fs(void)
|
|
{
|
|
struct hstate *h;
|
|
int error;
|
|
int i;
|
|
|
|
if (!hugepages_supported()) {
|
|
pr_info("disabling because there are no supported hugepage sizes\n");
|
|
return -ENOTSUPP;
|
|
}
|
|
|
|
error = -ENOMEM;
|
|
hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache",
|
|
sizeof(struct hugetlbfs_inode_info),
|
|
0, SLAB_ACCOUNT, init_once);
|
|
if (hugetlbfs_inode_cachep == NULL)
|
|
goto out2;
|
|
|
|
error = register_filesystem(&hugetlbfs_fs_type);
|
|
if (error)
|
|
goto out;
|
|
|
|
i = 0;
|
|
for_each_hstate(h) {
|
|
char buf[50];
|
|
unsigned ps_kb = 1U << (h->order + PAGE_SHIFT - 10);
|
|
|
|
snprintf(buf, sizeof(buf), "pagesize=%uK", ps_kb);
|
|
hugetlbfs_vfsmount[i] = kern_mount_data(&hugetlbfs_fs_type,
|
|
buf);
|
|
|
|
if (IS_ERR(hugetlbfs_vfsmount[i])) {
|
|
pr_err("Cannot mount internal hugetlbfs for "
|
|
"page size %uK", ps_kb);
|
|
error = PTR_ERR(hugetlbfs_vfsmount[i]);
|
|
hugetlbfs_vfsmount[i] = NULL;
|
|
}
|
|
i++;
|
|
}
|
|
/* Non default hstates are optional */
|
|
if (!IS_ERR_OR_NULL(hugetlbfs_vfsmount[default_hstate_idx]))
|
|
return 0;
|
|
|
|
out:
|
|
kmem_cache_destroy(hugetlbfs_inode_cachep);
|
|
out2:
|
|
return error;
|
|
}
|
|
fs_initcall(init_hugetlbfs_fs)
|