pgoff_t index, void *expected, void *replacement)
{
struct radix_tree_node *node;
- void **pslot;
+ void __rcu **pslot;
void *item;
VM_BUG_ON(!expected);
#ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE
/* ifdef here to avoid bloating shmem.o when not necessary */
-int shmem_huge __read_mostly;
+static int shmem_huge __read_mostly;
#if defined(CONFIG_SYSFS) || defined(CONFIG_TMPFS)
static int shmem_parse_huge(const char *str)
}
#endif /* CONFIG_TRANSPARENT_HUGE_PAGECACHE */
+static inline bool is_huge_enabled(struct shmem_sb_info *sbinfo)
+{
+ if (IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE) &&
+ (shmem_huge == SHMEM_HUGE_FORCE || sbinfo->huge) &&
+ shmem_huge != SHMEM_HUGE_DENY)
+ return true;
+ return false;
+}
+
/*
* Like add_to_page_cache_locked, but error if expected item has gone.
*/
pgoff_t start, pgoff_t end)
{
struct radix_tree_iter iter;
- void **slot;
+ void __rcu **slot;
struct page *page;
unsigned long swapped = 0;
{
struct inode *inode = path->dentry->d_inode;
struct shmem_inode_info *info = SHMEM_I(inode);
+ struct shmem_sb_info *sb_info = SHMEM_SB(inode->i_sb);
if (info->alloced - info->swapped != inode->i_mapping->nrpages) {
spin_lock_irq(&info->lock);
spin_unlock_irq(&info->lock);
}
generic_fillattr(inode, stat);
+
+ if (is_huge_enabled(sb_info))
+ stat->blksize = HPAGE_PMD_SIZE;
+
return 0;
}
static unsigned long find_swap_entry(struct radix_tree_root *root, void *item)
{
struct radix_tree_iter iter;
- void **slot;
+ void __rcu **slot;
unsigned long found = -1;
unsigned int checked = 0;
rcu_read_lock();
radix_tree_for_each_slot(slot, root, &iter, 0) {
- if (*slot == item) {
+ void *entry = radix_tree_deref_slot(slot);
+
+ if (radix_tree_deref_retry(entry)) {
+ slot = radix_tree_iter_retry(&iter);
+ continue;
+ }
+ if (entry == item) {
found = iter.index;
break;
}
if (!swap.val)
goto redirty;
- if (mem_cgroup_try_charge_swap(page, swap))
- goto free_swap;
-
/*
* Add inode to shmem_unuse()'s list of swapped-out inodes,
* if it's not already there. Do it now before the page is
}
mutex_unlock(&shmem_swaplist_mutex);
-free_swap:
put_swap_page(page, swap);
redirty:
set_page_dirty(page);
struct shmem_inode_info *info, pgoff_t index)
{
/* Create a pseudo vma that just contains the policy */
- vma->vm_start = 0;
+ memset(vma, 0, sizeof(*vma));
/* Bias interleave by inode number to distribute better across nodes */
vma->vm_pgoff = index + info->vfs_inode.i_ino;
- vma->vm_ops = NULL;
vma->vm_policy = mpol_shared_policy_lookup(&info->policy, index);
}
return ret;
}
-static int shmem_fault(struct vm_fault *vmf)
+static vm_fault_t shmem_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct inode *inode = file_inode(vma->vm_file);
gfp_t gfp = mapping_gfp_mask(inode->i_mapping);
enum sgp_type sgp;
- int error;
- int ret = VM_FAULT_LOCKED;
+ int err;
+ vm_fault_t ret = VM_FAULT_LOCKED;
/*
* Trinity finds that probing a hole which tmpfs is punching can
else if (vma->vm_flags & VM_HUGEPAGE)
sgp = SGP_HUGE;
- error = shmem_getpage_gfp(inode, vmf->pgoff, &vmf->page, sgp,
+ err = shmem_getpage_gfp(inode, vmf->pgoff, &vmf->page, sgp,
gfp, vma, vmf, &ret);
- if (error)
- return ((error == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS);
+ if (err)
+ return vmf_error(err);
return ret;
}
return offset;
}
-/*
- * We need a tag: a new tag would expand every radix_tree_node by 8 bytes,
- * so reuse a tag which we firmly believe is never set or cleared on shmem.
- */
-#define SHMEM_TAG_PINNED PAGECACHE_TAG_TOWRITE
-#define LAST_SCAN 4 /* about 150ms max */
-
-static void shmem_tag_pins(struct address_space *mapping)
-{
- struct radix_tree_iter iter;
- void **slot;
- pgoff_t start;
- struct page *page;
-
- lru_add_drain();
- start = 0;
- rcu_read_lock();
-
- radix_tree_for_each_slot(slot, &mapping->i_pages, &iter, start) {
- page = radix_tree_deref_slot(slot);
- if (!page || radix_tree_exception(page)) {
- if (radix_tree_deref_retry(page)) {
- slot = radix_tree_iter_retry(&iter);
- continue;
- }
- } else if (page_count(page) - page_mapcount(page) > 1) {
- xa_lock_irq(&mapping->i_pages);
- radix_tree_tag_set(&mapping->i_pages, iter.index,
- SHMEM_TAG_PINNED);
- xa_unlock_irq(&mapping->i_pages);
- }
-
- if (need_resched()) {
- slot = radix_tree_iter_resume(slot, &iter);
- cond_resched_rcu();
- }
- }
- rcu_read_unlock();
-}
-
-/*
- * Setting SEAL_WRITE requires us to verify there's no pending writer. However,
- * via get_user_pages(), drivers might have some pending I/O without any active
- * user-space mappings (eg., direct-IO, AIO). Therefore, we look at all pages
- * and see whether it has an elevated ref-count. If so, we tag them and wait for
- * them to be dropped.
- * The caller must guarantee that no new user will acquire writable references
- * to those pages to avoid races.
- */
-static int shmem_wait_for_pins(struct address_space *mapping)
-{
- struct radix_tree_iter iter;
- void **slot;
- pgoff_t start;
- struct page *page;
- int error, scan;
-
- shmem_tag_pins(mapping);
-
- error = 0;
- for (scan = 0; scan <= LAST_SCAN; scan++) {
- if (!radix_tree_tagged(&mapping->i_pages, SHMEM_TAG_PINNED))
- break;
-
- if (!scan)
- lru_add_drain_all();
- else if (schedule_timeout_killable((HZ << scan) / 200))
- scan = LAST_SCAN;
-
- start = 0;
- rcu_read_lock();
- radix_tree_for_each_tagged(slot, &mapping->i_pages, &iter,
- start, SHMEM_TAG_PINNED) {
-
- page = radix_tree_deref_slot(slot);
- if (radix_tree_exception(page)) {
- if (radix_tree_deref_retry(page)) {
- slot = radix_tree_iter_retry(&iter);
- continue;
- }
-
- page = NULL;
- }
-
- if (page &&
- page_count(page) - page_mapcount(page) != 1) {
- if (scan < LAST_SCAN)
- goto continue_resched;
-
- /*
- * On the last scan, we clean up all those tags
- * we inserted; but make a note that we still
- * found pages pinned.
- */
- error = -EBUSY;
- }
-
- xa_lock_irq(&mapping->i_pages);
- radix_tree_tag_clear(&mapping->i_pages,
- iter.index, SHMEM_TAG_PINNED);
- xa_unlock_irq(&mapping->i_pages);
-continue_resched:
- if (need_resched()) {
- slot = radix_tree_iter_resume(slot, &iter);
- cond_resched_rcu();
- }
- }
- rcu_read_unlock();
- }
-
- return error;
-}
-
-static unsigned int *memfd_file_seals_ptr(struct file *file)
-{
- if (file->f_op == &shmem_file_operations)
- return &SHMEM_I(file_inode(file))->seals;
-
-#ifdef CONFIG_HUGETLBFS
- if (file->f_op == &hugetlbfs_file_operations)
- return &HUGETLBFS_I(file_inode(file))->seals;
-#endif
-
- return NULL;
-}
-
-#define F_ALL_SEALS (F_SEAL_SEAL | \
- F_SEAL_SHRINK | \
- F_SEAL_GROW | \
- F_SEAL_WRITE)
-
-static int memfd_add_seals(struct file *file, unsigned int seals)
-{
- struct inode *inode = file_inode(file);
- unsigned int *file_seals;
- int error;
-
- /*
- * SEALING
- * Sealing allows multiple parties to share a shmem-file but restrict
- * access to a specific subset of file operations. Seals can only be
- * added, but never removed. This way, mutually untrusted parties can
- * share common memory regions with a well-defined policy. A malicious
- * peer can thus never perform unwanted operations on a shared object.
- *
- * Seals are only supported on special shmem-files and always affect
- * the whole underlying inode. Once a seal is set, it may prevent some
- * kinds of access to the file. Currently, the following seals are
- * defined:
- * SEAL_SEAL: Prevent further seals from being set on this file
- * SEAL_SHRINK: Prevent the file from shrinking
- * SEAL_GROW: Prevent the file from growing
- * SEAL_WRITE: Prevent write access to the file
- *
- * As we don't require any trust relationship between two parties, we
- * must prevent seals from being removed. Therefore, sealing a file
- * only adds a given set of seals to the file, it never touches
- * existing seals. Furthermore, the "setting seals"-operation can be
- * sealed itself, which basically prevents any further seal from being
- * added.
- *
- * Semantics of sealing are only defined on volatile files. Only
- * anonymous shmem files support sealing. More importantly, seals are
- * never written to disk. Therefore, there's no plan to support it on
- * other file types.
- */
-
- if (!(file->f_mode & FMODE_WRITE))
- return -EPERM;
- if (seals & ~(unsigned int)F_ALL_SEALS)
- return -EINVAL;
-
- inode_lock(inode);
-
- file_seals = memfd_file_seals_ptr(file);
- if (!file_seals) {
- error = -EINVAL;
- goto unlock;
- }
-
- if (*file_seals & F_SEAL_SEAL) {
- error = -EPERM;
- goto unlock;
- }
-
- if ((seals & F_SEAL_WRITE) && !(*file_seals & F_SEAL_WRITE)) {
- error = mapping_deny_writable(file->f_mapping);
- if (error)
- goto unlock;
-
- error = shmem_wait_for_pins(file->f_mapping);
- if (error) {
- mapping_allow_writable(file->f_mapping);
- goto unlock;
- }
- }
-
- *file_seals |= seals;
- error = 0;
-
-unlock:
- inode_unlock(inode);
- return error;
-}
-
-static int memfd_get_seals(struct file *file)
-{
- unsigned int *seals = memfd_file_seals_ptr(file);
-
- return seals ? *seals : -EINVAL;
-}
-
-long memfd_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
-{
- long error;
-
- switch (cmd) {
- case F_ADD_SEALS:
- /* disallow upper 32bit */
- if (arg > UINT_MAX)
- return -EINVAL;
-
- error = memfd_add_seals(file, arg);
- break;
- case F_GET_SEALS:
- error = memfd_get_seals(file);
- break;
- default:
- error = -EINVAL;
- break;
- }
-
- return error;
-}
-
static long shmem_fallocate(struct file *file, int mode, loff_t offset,
loff_t len)
{
if (len > PAGE_SIZE)
return -ENAMETOOLONG;
- inode = shmem_get_inode(dir->i_sb, dir, S_IFLNK|S_IRWXUGO, 0, VM_NORESERVE);
+ inode = shmem_get_inode(dir->i_sb, dir, S_IFLNK | 0777, 0,
+ VM_NORESERVE);
if (!inode)
return -ENOSPC;
return ino->i_ino == inum && fh[0] == ino->i_generation;
}
+/* Find any alias of inode, but prefer a hashed alias */
+static struct dentry *shmem_find_alias(struct inode *inode)
+{
+ struct dentry *alias = d_find_alias(inode);
+
+ return alias ?: d_find_any_alias(inode);
+}
+
+
static struct dentry *shmem_fh_to_dentry(struct super_block *sb,
struct fid *fid, int fh_len, int fh_type)
{
inode = ilookup5(sb, (unsigned long)(inum + fid->raw[0]),
shmem_match, fid->raw);
if (inode) {
- dentry = d_find_alias(inode);
+ dentry = shmem_find_alias(inode);
iput(inode);
}
sbinfo->max_blocks << (PAGE_SHIFT - 10));
if (sbinfo->max_inodes != shmem_default_max_inodes())
seq_printf(seq, ",nr_inodes=%lu", sbinfo->max_inodes);
- if (sbinfo->mode != (S_IRWXUGO | S_ISVTX))
+ if (sbinfo->mode != (0777 | S_ISVTX))
seq_printf(seq, ",mode=%03ho", sbinfo->mode);
if (!uid_eq(sbinfo->uid, GLOBAL_ROOT_UID))
seq_printf(seq, ",uid=%u",
return 0;
}
-#define MFD_NAME_PREFIX "memfd:"
-#define MFD_NAME_PREFIX_LEN (sizeof(MFD_NAME_PREFIX) - 1)
-#define MFD_NAME_MAX_LEN (NAME_MAX - MFD_NAME_PREFIX_LEN)
-
-#define MFD_ALL_FLAGS (MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_HUGETLB)
-
-SYSCALL_DEFINE2(memfd_create,
- const char __user *, uname,
- unsigned int, flags)
-{
- unsigned int *file_seals;
- struct file *file;
- int fd, error;
- char *name;
- long len;
-
- if (!(flags & MFD_HUGETLB)) {
- if (flags & ~(unsigned int)MFD_ALL_FLAGS)
- return -EINVAL;
- } else {
- /* Allow huge page size encoding in flags. */
- if (flags & ~(unsigned int)(MFD_ALL_FLAGS |
- (MFD_HUGE_MASK << MFD_HUGE_SHIFT)))
- return -EINVAL;
- }
-
- /* length includes terminating zero */
- len = strnlen_user(uname, MFD_NAME_MAX_LEN + 1);
- if (len <= 0)
- return -EFAULT;
- if (len > MFD_NAME_MAX_LEN + 1)
- return -EINVAL;
-
- name = kmalloc(len + MFD_NAME_PREFIX_LEN, GFP_KERNEL);
- if (!name)
- return -ENOMEM;
-
- strcpy(name, MFD_NAME_PREFIX);
- if (copy_from_user(&name[MFD_NAME_PREFIX_LEN], uname, len)) {
- error = -EFAULT;
- goto err_name;
- }
-
- /* terminating-zero may have changed after strnlen_user() returned */
- if (name[len + MFD_NAME_PREFIX_LEN - 1]) {
- error = -EFAULT;
- goto err_name;
- }
-
- fd = get_unused_fd_flags((flags & MFD_CLOEXEC) ? O_CLOEXEC : 0);
- if (fd < 0) {
- error = fd;
- goto err_name;
- }
-
- if (flags & MFD_HUGETLB) {
- struct user_struct *user = NULL;
-
- file = hugetlb_file_setup(name, 0, VM_NORESERVE, &user,
- HUGETLB_ANONHUGE_INODE,
- (flags >> MFD_HUGE_SHIFT) &
- MFD_HUGE_MASK);
- } else
- file = shmem_file_setup(name, 0, VM_NORESERVE);
- if (IS_ERR(file)) {
- error = PTR_ERR(file);
- goto err_fd;
- }
- file->f_mode |= FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE;
- file->f_flags |= O_RDWR | O_LARGEFILE;
-
- if (flags & MFD_ALLOW_SEALING) {
- file_seals = memfd_file_seals_ptr(file);
- *file_seals &= ~F_SEAL_SEAL;
- }
-
- fd_install(fd, file);
- kfree(name);
- return fd;
-
-err_fd:
- put_unused_fd(fd);
-err_name:
- kfree(name);
- return error;
-}
-
#endif /* CONFIG_TMPFS */
static void shmem_put_super(struct super_block *sb)
if (!sbinfo)
return -ENOMEM;
- sbinfo->mode = S_IRWXUGO | S_ISVTX;
+ sbinfo->mode = 0777 | S_ISVTX;
sbinfo->uid = current_fsuid();
sbinfo->gid = current_fsgid();
sb->s_fs_info = sbinfo;
d_set_d_op(path.dentry, &anon_ops);
res = ERR_PTR(-ENOSPC);
- inode = shmem_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0, flags);
+ inode = shmem_get_inode(sb, NULL, S_IFREG | 0777, 0, flags);
if (!inode)
goto put_memory;
projects / linux-2.6-microblaze.git / blobdiff