| /* |
| * hugetlbpage-backed filesystem. Based on ramfs. |
| * |
| * William Irwin, 2002 |
| * |
| * Copyright (C) 2002 Linus Torvalds. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/thread_info.h> |
| #include <asm/current.h> |
| #include <linux/sched.h> /* remove ASAP */ |
| #include <linux/fs.h> |
| #include <linux/mount.h> |
| #include <linux/file.h> |
| #include <linux/kernel.h> |
| #include <linux/writeback.h> |
| #include <linux/pagemap.h> |
| #include <linux/highmem.h> |
| #include <linux/init.h> |
| #include <linux/string.h> |
| #include <linux/capability.h> |
| #include <linux/ctype.h> |
| #include <linux/backing-dev.h> |
| #include <linux/hugetlb.h> |
| #include <linux/pagevec.h> |
| #include <linux/parser.h> |
| #include <linux/mman.h> |
| #include <linux/slab.h> |
| #include <linux/dnotify.h> |
| #include <linux/statfs.h> |
| #include <linux/security.h> |
| #include <linux/magic.h> |
| #include <linux/migrate.h> |
| |
| #include <asm/uaccess.h> |
| |
| static const struct super_operations hugetlbfs_ops; |
| static const struct address_space_operations hugetlbfs_aops; |
| const struct file_operations hugetlbfs_file_operations; |
| static const struct inode_operations hugetlbfs_dir_inode_operations; |
| static const struct inode_operations hugetlbfs_inode_operations; |
| |
| static struct backing_dev_info hugetlbfs_backing_dev_info = { |
| .name = "hugetlbfs", |
| .ra_pages = 0, /* No readahead */ |
| .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, |
| }; |
| |
| int sysctl_hugetlb_shm_group; |
| |
| enum { |
| Opt_size, Opt_nr_inodes, |
| Opt_mode, Opt_uid, Opt_gid, |
| Opt_pagesize, |
| Opt_err, |
| }; |
| |
| static const match_table_t tokens = { |
| {Opt_size, "size=%s"}, |
| {Opt_nr_inodes, "nr_inodes=%s"}, |
| {Opt_mode, "mode=%o"}, |
| {Opt_uid, "uid=%u"}, |
| {Opt_gid, "gid=%u"}, |
| {Opt_pagesize, "pagesize=%s"}, |
| {Opt_err, NULL}, |
| }; |
| |
| static void huge_pagevec_release(struct pagevec *pvec) |
| { |
| int i; |
| |
| for (i = 0; i < pagevec_count(pvec); ++i) |
| put_page(pvec->pages[i]); |
| |
| pagevec_reinit(pvec); |
| } |
| |
| static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) |
| { |
| struct inode *inode = file->f_path.dentry->d_inode; |
| loff_t len, vma_len; |
| int ret; |
| struct hstate *h = hstate_file(file); |
| |
| /* |
| * vma address alignment (but not the pgoff alignment) has |
| * already been checked by prepare_hugepage_range. If you add |
| * any error returns here, do so after setting VM_HUGETLB, so |
| * is_vm_hugetlb_page tests below unmap_region go the right |
| * way when do_mmap_pgoff unwinds (may be important on powerpc |
| * and ia64). |
| */ |
| vma->vm_flags |= VM_HUGETLB | VM_RESERVED; |
| vma->vm_ops = &hugetlb_vm_ops; |
| |
| if (vma->vm_pgoff & (~huge_page_mask(h) >> PAGE_SHIFT)) |
| return -EINVAL; |
| |
| vma_len = (loff_t)(vma->vm_end - vma->vm_start); |
| |
| mutex_lock(&inode->i_mutex); |
| file_accessed(file); |
| |
| ret = -ENOMEM; |
| len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); |
| |
| if (hugetlb_reserve_pages(inode, |
| vma->vm_pgoff >> huge_page_order(h), |
| len >> huge_page_shift(h), vma, |
| vma->vm_flags)) |
| goto out; |
| |
| ret = 0; |
| hugetlb_prefault_arch_hook(vma->vm_mm); |
| if (vma->vm_flags & VM_WRITE && inode->i_size < len) |
| inode->i_size = len; |
| out: |
| mutex_unlock(&inode->i_mutex); |
| |
| return ret; |
| } |
| |
| /* |
| * Called under down_write(mmap_sem). |
| */ |
| |
| #ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA |
| static unsigned long |
| hugetlb_get_unmapped_area(struct file *file, unsigned long addr, |
| unsigned long len, unsigned long pgoff, unsigned long flags) |
| { |
| struct mm_struct *mm = current->mm; |
| struct vm_area_struct *vma; |
| unsigned long start_addr; |
| struct hstate *h = hstate_file(file); |
| |
| if (len & ~huge_page_mask(h)) |
| return -EINVAL; |
| if (len > TASK_SIZE) |
| return -ENOMEM; |
| |
| if (flags & MAP_FIXED) { |
| if (prepare_hugepage_range(file, addr, len)) |
| return -EINVAL; |
| return addr; |
| } |
| |
| if (addr) { |
| addr = ALIGN(addr, huge_page_size(h)); |
| vma = find_vma(mm, addr); |
| if (TASK_SIZE - len >= addr && |
| (!vma || addr + len <= vma->vm_start)) |
| return addr; |
| } |
| |
| start_addr = mm->free_area_cache; |
| |
| if (len <= mm->cached_hole_size) |
| start_addr = TASK_UNMAPPED_BASE; |
| |
| full_search: |
| addr = ALIGN(start_addr, huge_page_size(h)); |
| |
| for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { |
| /* At this point: (!vma || addr < vma->vm_end). */ |
| if (TASK_SIZE - len < addr) { |
| /* |
| * Start a new search - just in case we missed |
| * some holes. |
| */ |
| if (start_addr != TASK_UNMAPPED_BASE) { |
| start_addr = TASK_UNMAPPED_BASE; |
| goto full_search; |
| } |
| return -ENOMEM; |
| } |
| |
| if (!vma || addr + len <= vma->vm_start) |
| return addr; |
| addr = ALIGN(vma->vm_end, huge_page_size(h)); |
| } |
| } |
| #endif |
| |
| static int |
| hugetlbfs_read_actor(struct page *page, unsigned long offset, |
| char __user *buf, unsigned long count, |
| unsigned long size) |
| { |
| char *kaddr; |
| unsigned long left, copied = 0; |
| int i, chunksize; |
| |
| if (size > count) |
| size = count; |
| |
| /* Find which 4k chunk and offset with in that chunk */ |
| i = offset >> PAGE_CACHE_SHIFT; |
| offset = offset & ~PAGE_CACHE_MASK; |
| |
| while (size) { |
| chunksize = PAGE_CACHE_SIZE; |
| if (offset) |
| chunksize -= offset; |
| if (chunksize > size) |
| chunksize = size; |
| kaddr = kmap(&page[i]); |
| left = __copy_to_user(buf, kaddr + offset, chunksize); |
| kunmap(&page[i]); |
| if (left) { |
| copied += (chunksize - left); |
| break; |
| } |
| offset = 0; |
| size -= chunksize; |
| buf += chunksize; |
| copied += chunksize; |
| i++; |
| } |
| return copied ? copied : -EFAULT; |
| } |
| |
| /* |
| * Support for read() - Find the page attached to f_mapping and copy out the |
| * data. Its *very* similar to do_generic_mapping_read(), we can't use that |
| * since it has PAGE_CACHE_SIZE assumptions. |
| */ |
| static ssize_t hugetlbfs_read(struct file *filp, char __user *buf, |
| size_t len, loff_t *ppos) |
| { |
| struct hstate *h = hstate_file(filp); |
| struct address_space *mapping = filp->f_mapping; |
| struct inode *inode = mapping->host; |
| unsigned long index = *ppos >> huge_page_shift(h); |
| unsigned long offset = *ppos & ~huge_page_mask(h); |
| unsigned long end_index; |
| loff_t isize; |
| ssize_t retval = 0; |
| |
| mutex_lock(&inode->i_mutex); |
| |
| /* validate length */ |
| if (len == 0) |
| goto out; |
| |
| isize = i_size_read(inode); |
| if (!isize) |
| goto out; |
| |
| end_index = (isize - 1) >> huge_page_shift(h); |
| for (;;) { |
| struct page *page; |
| unsigned long nr, ret; |
| int ra; |
| |
| /* nr is the maximum number of bytes to copy from this page */ |
| nr = huge_page_size(h); |
| if (index >= end_index) { |
| if (index > end_index) |
| goto out; |
| nr = ((isize - 1) & ~huge_page_mask(h)) + 1; |
| if (nr <= offset) { |
| goto out; |
| } |
| } |
| nr = nr - offset; |
| |
| /* Find the page */ |
| page = find_get_page(mapping, index); |
| if (unlikely(page == NULL)) { |
| /* |
| * We have a HOLE, zero out the user-buffer for the |
| * length of the hole or request. |
| */ |
| ret = len < nr ? len : nr; |
| if (clear_user(buf, ret)) |
| ra = -EFAULT; |
| else |
| ra = 0; |
| } else { |
| /* |
| * We have the page, copy it to user space buffer. |
| */ |
| ra = hugetlbfs_read_actor(page, offset, buf, len, nr); |
| ret = ra; |
| } |
| if (ra < 0) { |
| if (retval == 0) |
| retval = ra; |
| if (page) |
| page_cache_release(page); |
| goto out; |
| } |
| |
| offset += ret; |
| retval += ret; |
| len -= ret; |
| index += offset >> huge_page_shift(h); |
| offset &= ~huge_page_mask(h); |
| |
| if (page) |
| page_cache_release(page); |
| |
| /* short read or no more work */ |
| if ((ret != nr) || (len == 0)) |
| break; |
| } |
| out: |
| *ppos = ((loff_t)index << huge_page_shift(h)) + offset; |
| mutex_unlock(&inode->i_mutex); |
| return retval; |
| } |
| |
| static int hugetlbfs_write_begin(struct file *file, |
| struct address_space *mapping, |
| loff_t pos, unsigned len, unsigned flags, |
| struct page **pagep, void **fsdata) |
| { |
| return -EINVAL; |
| } |
| |
| static int hugetlbfs_write_end(struct file *file, struct address_space *mapping, |
| loff_t pos, unsigned len, unsigned copied, |
| struct page *page, void *fsdata) |
| { |
| BUG(); |
| return -EINVAL; |
| } |
| |
| static void truncate_huge_page(struct page *page) |
| { |
| cancel_dirty_page(page, /* No IO accounting for huge pages? */0); |
| ClearPageUptodate(page); |
| delete_from_page_cache(page); |
| } |
| |
| static void truncate_hugepages(struct inode *inode, loff_t lstart) |
| { |
| struct hstate *h = hstate_inode(inode); |
| struct address_space *mapping = &inode->i_data; |
| const pgoff_t start = lstart >> huge_page_shift(h); |
| struct pagevec pvec; |
| pgoff_t next; |
| int i, freed = 0; |
| |
| pagevec_init(&pvec, 0); |
| next = start; |
| while (1) { |
| if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { |
| if (next == start) |
| break; |
| next = start; |
| continue; |
| } |
| |
| for (i = 0; i < pagevec_count(&pvec); ++i) { |
| struct page *page = pvec.pages[i]; |
| |
| lock_page(page); |
| if (page->index > next) |
| next = page->index; |
| ++next; |
| truncate_huge_page(page); |
| unlock_page(page); |
| freed++; |
| } |
| huge_pagevec_release(&pvec); |
| } |
| BUG_ON(!lstart && mapping->nrpages); |
| hugetlb_unreserve_pages(inode, start, freed); |
| } |
| |
| static void hugetlbfs_evict_inode(struct inode *inode) |
| { |
| truncate_hugepages(inode, 0); |
| end_writeback(inode); |
| } |
| |
| static inline void |
| hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff) |
| { |
| struct vm_area_struct *vma; |
| struct prio_tree_iter iter; |
| |
| vma_prio_tree_foreach(vma, &iter, root, pgoff, ULONG_MAX) { |
| unsigned long v_offset; |
| |
| /* |
| * Can the expression below overflow on 32-bit arches? |
| * No, because the prio_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 < pgoff) |
| v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT; |
| else |
| v_offset = 0; |
| |
| __unmap_hugepage_range(vma, |
| vma->vm_start + v_offset, vma->vm_end, NULL); |
| } |
| } |
| |
| static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) |
| { |
| pgoff_t pgoff; |
| struct address_space *mapping = inode->i_mapping; |
| struct hstate *h = hstate_inode(inode); |
| |
| BUG_ON(offset & ~huge_page_mask(h)); |
| pgoff = offset >> PAGE_SHIFT; |
| |
| i_size_write(inode, offset); |
| mutex_lock(&mapping->i_mmap_mutex); |
| if (!prio_tree_empty(&mapping->i_mmap)) |
| hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff); |
| mutex_unlock(&mapping->i_mmap_mutex); |
| truncate_hugepages(inode, offset); |
| return 0; |
| } |
| |
| static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) |
| { |
| struct inode *inode = dentry->d_inode; |
| struct hstate *h = hstate_inode(inode); |
| int error; |
| unsigned int ia_valid = attr->ia_valid; |
| |
| BUG_ON(!inode); |
| |
| error = inode_change_ok(inode, attr); |
| if (error) |
| return error; |
| |
| if (ia_valid & ATTR_SIZE) { |
| error = -EINVAL; |
| if (attr->ia_size & ~huge_page_mask(h)) |
| return -EINVAL; |
| error = hugetlb_vmtruncate(inode, attr->ia_size); |
| if (error) |
| return error; |
| } |
| |
| setattr_copy(inode, attr); |
| mark_inode_dirty(inode); |
| return 0; |
| } |
| |
| static struct inode *hugetlbfs_get_inode(struct super_block *sb, uid_t uid, |
| gid_t gid, int mode, dev_t dev) |
| { |
| struct inode *inode; |
| |
| inode = new_inode(sb); |
| if (inode) { |
| struct hugetlbfs_inode_info *info; |
| inode->i_ino = get_next_ino(); |
| inode->i_mode = mode; |
| inode->i_uid = uid; |
| inode->i_gid = gid; |
| inode->i_mapping->a_ops = &hugetlbfs_aops; |
| inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info; |
| inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; |
| INIT_LIST_HEAD(&inode->i_mapping->private_list); |
| info = HUGETLBFS_I(inode); |
| /* |
| * 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 |
| * call mpol_free_shared_policy() it will just return because |
| * the rb tree will still be empty. |
| */ |
| mpol_shared_policy_init(&info->policy, NULL); |
| 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; |
| break; |
| } |
| lockdep_annotate_inode_mutex_key(inode); |
| } |
| 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; |
| gid_t gid; |
| |
| if (dir->i_mode & S_ISGID) { |
| gid = dir->i_gid; |
| if (S_ISDIR(mode)) |
| mode |= S_ISGID; |
| } else { |
| gid = current_fsgid(); |
| } |
| inode = hugetlbfs_get_inode(dir->i_sb, current_fsuid(), gid, mode, dev); |
| if (inode) { |
| dir->i_ctime = dir->i_mtime = CURRENT_TIME; |
| 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, struct nameidata *nd) |
| { |
| 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; |
| gid_t gid; |
| |
| if (dir->i_mode & S_ISGID) |
| gid = dir->i_gid; |
| else |
| gid = current_fsgid(); |
| |
| inode = hugetlbfs_get_inode(dir->i_sb, current_fsuid(), |
| gid, 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; |
| |
| 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) |
| { |
| int rc; |
| |
| rc = migrate_huge_page_move_mapping(mapping, newpage, page); |
| if (rc) |
| return rc; |
| migrate_page_copy(newpage, page); |
| |
| 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(dentry->d_inode); |
| |
| 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->max_blocks >= 0) { |
| buf->f_blocks = sbinfo->max_blocks; |
| buf->f_bavail = buf->f_bfree = sbinfo->free_blocks; |
| 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; |
| 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; |
| } |
| 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, |
| }; |
| |
| |
| 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 = hugetlbfs_read, |
| .mmap = hugetlbfs_file_mmap, |
| .fsync = noop_fsync, |
| .get_unmapped_area = hugetlb_get_unmapped_area, |
| .llseek = default_llseek, |
| }; |
| |
| 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 = generic_show_options, |
| }; |
| |
| 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 size = 0; |
| enum { NO_SIZE, SIZE_STD, SIZE_PERCENT } setsize = 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 = option; |
| break; |
| |
| case Opt_gid: |
| if (match_int(&args[0], &option)) |
| goto bad_val; |
| pconfig->gid = option; |
| 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; |
| size = memparse(args[0].from, &rest); |
| setsize = SIZE_STD; |
| if (*rest == '%') |
| setsize = 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) { |
| printk(KERN_ERR |
| "hugetlbfs: Unsupported page size %lu MB\n", |
| ps >> 20); |
| return -EINVAL; |
| } |
| break; |
| } |
| |
| default: |
| printk(KERN_ERR "hugetlbfs: Bad mount option: \"%s\"\n", |
| p); |
| return -EINVAL; |
| break; |
| } |
| } |
| |
| /* Do size after hstate is set up */ |
| if (setsize > NO_SIZE) { |
| struct hstate *h = pconfig->hstate; |
| if (setsize == SIZE_PERCENT) { |
| size <<= huge_page_shift(h); |
| size *= h->max_huge_pages; |
| do_div(size, 100); |
| } |
| pconfig->nr_blocks = (size >> huge_page_shift(h)); |
| } |
| |
| return 0; |
| |
| bad_val: |
| printk(KERN_ERR "hugetlbfs: 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) |
| { |
| struct inode * inode; |
| struct dentry * root; |
| int ret; |
| struct hugetlbfs_config config; |
| struct hugetlbfs_sb_info *sbinfo; |
| |
| save_mount_options(sb, data); |
| |
| config.nr_blocks = -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; |
| 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_blocks = config.nr_blocks; |
| sbinfo->free_blocks = config.nr_blocks; |
| sbinfo->max_inodes = config.nr_inodes; |
| sbinfo->free_inodes = config.nr_inodes; |
| 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; |
| inode = hugetlbfs_get_inode(sb, config.uid, config.gid, |
| S_IFDIR | config.mode, 0); |
| if (!inode) |
| goto out_free; |
| |
| root = d_alloc_root(inode); |
| if (!root) { |
| iput(inode); |
| goto out_free; |
| } |
| sb->s_root = root; |
| return 0; |
| out_free: |
| kfree(sbinfo); |
| return -ENOMEM; |
| } |
| |
| int hugetlb_get_quota(struct address_space *mapping, long delta) |
| { |
| int ret = 0; |
| struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); |
| |
| if (sbinfo->free_blocks > -1) { |
| spin_lock(&sbinfo->stat_lock); |
| if (sbinfo->free_blocks - delta >= 0) |
| sbinfo->free_blocks -= delta; |
| else |
| ret = -ENOMEM; |
| spin_unlock(&sbinfo->stat_lock); |
| } |
| |
| return ret; |
| } |
| |
| void hugetlb_put_quota(struct address_space *mapping, long delta) |
| { |
| struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); |
| |
| if (sbinfo->free_blocks > -1) { |
| spin_lock(&sbinfo->stat_lock); |
| sbinfo->free_blocks += delta; |
| spin_unlock(&sbinfo->stat_lock); |
| } |
| } |
| |
| 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; |
| |
| static int can_do_hugetlb_shm(void) |
| { |
| return capable(CAP_IPC_LOCK) || in_group_p(sysctl_hugetlb_shm_group); |
| } |
| |
| struct file *hugetlb_file_setup(const char *name, size_t size, |
| vm_flags_t acctflag, |
| struct user_struct **user, int creat_flags) |
| { |
| int error = -ENOMEM; |
| struct file *file; |
| struct inode *inode; |
| struct path path; |
| struct dentry *root; |
| struct qstr quick_string; |
| |
| *user = NULL; |
| if (!hugetlbfs_vfsmount) |
| return ERR_PTR(-ENOENT); |
| |
| if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) { |
| *user = current_user(); |
| if (user_shm_lock(size, *user)) { |
| printk_once(KERN_WARNING "Using mlock ulimits for SHM_HUGETLB is deprecated\n"); |
| } else { |
| *user = NULL; |
| return ERR_PTR(-EPERM); |
| } |
| } |
| |
| root = hugetlbfs_vfsmount->mnt_root; |
| quick_string.name = name; |
| quick_string.len = strlen(quick_string.name); |
| quick_string.hash = 0; |
| path.dentry = d_alloc(root, &quick_string); |
| if (!path.dentry) |
| goto out_shm_unlock; |
| |
| path.mnt = mntget(hugetlbfs_vfsmount); |
| error = -ENOSPC; |
| inode = hugetlbfs_get_inode(root->d_sb, current_fsuid(), |
| current_fsgid(), S_IFREG | S_IRWXUGO, 0); |
| if (!inode) |
| goto out_dentry; |
| |
| error = -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); |
| |
| error = -ENFILE; |
| file = alloc_file(&path, FMODE_WRITE | FMODE_READ, |
| &hugetlbfs_file_operations); |
| if (!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 ERR_PTR(error); |
| } |
| |
| static int __init init_hugetlbfs_fs(void) |
| { |
| int error; |
| struct vfsmount *vfsmount; |
| |
| error = bdi_init(&hugetlbfs_backing_dev_info); |
| if (error) |
| return error; |
| |
| hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache", |
| sizeof(struct hugetlbfs_inode_info), |
| 0, 0, init_once); |
| if (hugetlbfs_inode_cachep == NULL) |
| goto out2; |
| |
| error = register_filesystem(&hugetlbfs_fs_type); |
| if (error) |
| goto out; |
| |
| vfsmount = kern_mount(&hugetlbfs_fs_type); |
| |
| if (!IS_ERR(vfsmount)) { |
| hugetlbfs_vfsmount = vfsmount; |
| return 0; |
| } |
| |
| error = PTR_ERR(vfsmount); |
| |
| out: |
| if (error) |
| kmem_cache_destroy(hugetlbfs_inode_cachep); |
| out2: |
| bdi_destroy(&hugetlbfs_backing_dev_info); |
| return error; |
| } |
| |
| static void __exit exit_hugetlbfs_fs(void) |
| { |
| kmem_cache_destroy(hugetlbfs_inode_cachep); |
| kern_unmount(hugetlbfs_vfsmount); |
| unregister_filesystem(&hugetlbfs_fs_type); |
| bdi_destroy(&hugetlbfs_backing_dev_info); |
| } |
| |
| module_init(init_hugetlbfs_fs) |
| module_exit(exit_hugetlbfs_fs) |
| |
| MODULE_LICENSE("GPL"); |