* Nadia Yvette Chambers, 2002
*
* Copyright (C) 2002 Linus Torvalds.
+ * License: GPL
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#include <linux/module.h>
#include <linux/thread_info.h>
#include <asm/current.h>
#include <linux/sched.h> /* remove ASAP */
delete_from_page_cache(page);
}
+static void
+hugetlb_vmdelete_list(struct rb_root *root, pgoff_t start, pgoff_t end)
+{
+ struct vm_area_struct *vma;
+
+ /*
+ * end == 0 indicates that the entire range after
+ * start should be unmapped.
+ */
+ vma_interval_tree_foreach(vma, root, start, end ? end : ULONG_MAX) {
+ unsigned long v_offset;
+ unsigned long v_end;
+
+ /*
+ * Can the expression below overflow on 32-bit arches?
+ * No, because the interval tree returns us only those vmas
+ * which overlap the truncated area starting at pgoff,
+ * and no vma on a 32-bit arch can span beyond the 4GB.
+ */
+ if (vma->vm_pgoff < start)
+ v_offset = (start - vma->vm_pgoff) << PAGE_SHIFT;
+ else
+ v_offset = 0;
+
+ if (!end)
+ v_end = vma->vm_end;
+ else {
+ v_end = ((end - vma->vm_pgoff) << PAGE_SHIFT)
+ + vma->vm_start;
+ if (v_end > vma->vm_end)
+ v_end = vma->vm_end;
+ }
+
+ unmap_hugepage_range(vma, vma->vm_start + v_offset, v_end,
+ NULL);
+ }
+}
/*
* remove_inode_hugepages handles two distinct cases: truncation and hole
* punch. There are subtle differences in operation for each case.
-
+ *
* truncation is indicated by end of range being LLONG_MAX
* In this case, we first scan the range and release found pages.
* After releasing pages, hugetlb_unreserve_pages cleans up region/reserv
for (i = 0; i < pagevec_count(&pvec); ++i) {
struct page *page = pvec.pages[i];
+ bool rsv_on_error;
u32 hash;
/*
mapping, next, 0);
mutex_lock(&hugetlb_fault_mutex_table[hash]);
- lock_page(page);
- if (likely(!page_mapped(page))) {
- bool rsv_on_error = !PagePrivate(page);
- /*
- * We must free the huge page and remove
- * from page cache (remove_huge_page) BEFORE
- * removing the region/reserve map
- * (hugetlb_unreserve_pages). In rare out
- * of memory conditions, removal of the
- * region/reserve map could fail. Before
- * free'ing the page, note PagePrivate which
- * is used in case of error.
- */
- remove_huge_page(page);
- freed++;
- if (!truncate_op) {
- if (unlikely(hugetlb_unreserve_pages(
- inode, next,
- next + 1, 1)))
- hugetlb_fix_reserve_counts(
- inode, rsv_on_error);
- }
- } else {
- /*
- * If page is mapped, it was faulted in after
- * being unmapped. It indicates a race between
- * hole punch and page fault. Do nothing in
- * this case. Getting here in a truncate
- * operation is a bug.
- */
+ /*
+ * If page is mapped, it was faulted in after being
+ * unmapped in caller. Unmap (again) now after taking
+ * the fault mutex. The mutex will prevent faults
+ * until we finish removing the page.
+ *
+ * This race can only happen in the hole punch case.
+ * Getting here in a truncate operation is a bug.
+ */
+ if (unlikely(page_mapped(page))) {
BUG_ON(truncate_op);
+
+ i_mmap_lock_write(mapping);
+ hugetlb_vmdelete_list(&mapping->i_mmap,
+ next * pages_per_huge_page(h),
+ (next + 1) * pages_per_huge_page(h));
+ i_mmap_unlock_write(mapping);
+ }
+
+ lock_page(page);
+ /*
+ * We must free the huge page and remove from page
+ * cache (remove_huge_page) BEFORE removing the
+ * region/reserve map (hugetlb_unreserve_pages). In
+ * rare out of memory conditions, removal of the
+ * region/reserve map could fail. Before free'ing
+ * the page, note PagePrivate which is used in case
+ * of error.
+ */
+ rsv_on_error = !PagePrivate(page);
+ remove_huge_page(page);
+ freed++;
+ if (!truncate_op) {
+ if (unlikely(hugetlb_unreserve_pages(inode,
+ next, next + 1, 1)))
+ hugetlb_fix_reserve_counts(inode,
+ rsv_on_error);
}
unlock_page(page);
clear_inode(inode);
}
-static inline void
-hugetlb_vmdelete_list(struct rb_root *root, pgoff_t start, pgoff_t end)
-{
- struct vm_area_struct *vma;
-
- /*
- * end == 0 indicates that the entire range after
- * start should be unmapped.
- */
- vma_interval_tree_foreach(vma, root, start, end ? end : ULONG_MAX) {
- unsigned long v_offset;
-
- /*
- * Can the expression below overflow on 32-bit arches?
- * No, because the interval tree returns us only those vmas
- * which overlap the truncated area starting at pgoff,
- * and no vma on a 32-bit arch can span beyond the 4GB.
- */
- if (vma->vm_pgoff < start)
- v_offset = (start - vma->vm_pgoff) << PAGE_SHIFT;
- else
- v_offset = 0;
-
- if (end) {
- end = ((end - start) << PAGE_SHIFT) +
- vma->vm_start + v_offset;
- if (end > vma->vm_end)
- end = vma->vm_end;
- } else
- end = vma->vm_end;
-
- unmap_hugepage_range(vma, vma->vm_start + v_offset, end, NULL);
- }
-}
-
static int hugetlb_vmtruncate(struct inode *inode, loff_t offset)
{
pgoff_t pgoff;
/*
* 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
+ * annotation because huge_pmd_share() does an allocation under hugetlb's
* i_mmap_rwsem.
*/
static struct lock_class_key hugetlbfs_i_mmap_rwsem_key;
/*
* The policy is initialized here even if we are creating a
* private inode because initialization simply creates an
- * an empty rb tree and calls spin_lock_init(), later when we
+ * an empty rb tree and calls rwlock_init(), later when we
* call mpol_free_shared_policy() it will just return because
* the rb tree will still be empty.
*/
.mount = hugetlbfs_mount,
.kill_sb = kill_litter_super,
};
-MODULE_ALIAS_FS("hugetlbfs");
static struct vfsmount *hugetlbfs_vfsmount[HUGE_MAX_HSTATE];
error = -ENOMEM;
hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache",
sizeof(struct hugetlbfs_inode_info),
- 0, 0, init_once);
+ 0, SLAB_ACCOUNT, init_once);
if (hugetlbfs_inode_cachep == NULL)
goto out2;
out2:
return error;
}
-
-static void __exit exit_hugetlbfs_fs(void)
-{
- struct hstate *h;
- int i;
-
-
- /*
- * Make sure all delayed rcu free inodes are flushed before we
- * destroy cache.
- */
- rcu_barrier();
- kmem_cache_destroy(hugetlbfs_inode_cachep);
- i = 0;
- for_each_hstate(h)
- kern_unmount(hugetlbfs_vfsmount[i++]);
- unregister_filesystem(&hugetlbfs_fs_type);
-}
-
-module_init(init_hugetlbfs_fs)
-module_exit(exit_hugetlbfs_fs)
-
-MODULE_LICENSE("GPL");
+fs_initcall(init_hugetlbfs_fs)
projects / deliverable / linux.git / blobdiff