diff options
author | 2005-04-16 15:20:36 -0700 | |
---|---|---|
committer | 2005-04-16 15:20:36 -0700 | |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/hugetlbfs | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2 linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/hugetlbfs')
-rw-r--r-- | fs/hugetlbfs/Makefile | 7 | ||||
-rw-r--r-- | fs/hugetlbfs/inode.c | 853 |
2 files changed, 860 insertions, 0 deletions
diff --git a/fs/hugetlbfs/Makefile b/fs/hugetlbfs/Makefile new file mode 100644 index 000000000000..6adf870c63c6 --- /dev/null +++ b/fs/hugetlbfs/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for the linux ramfs routines. +# + +obj-$(CONFIG_HUGETLBFS) += hugetlbfs.o + +hugetlbfs-objs := inode.o diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c new file mode 100644 index 000000000000..2af3338f891b --- /dev/null +++ b/fs/hugetlbfs/inode.c @@ -0,0 +1,853 @@ +/* + * 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/writeback.h> +#include <linux/pagemap.h> +#include <linux/highmem.h> +#include <linux/init.h> +#include <linux/string.h> +#include <linux/backing-dev.h> +#include <linux/hugetlb.h> +#include <linux/pagevec.h> +#include <linux/quotaops.h> +#include <linux/slab.h> +#include <linux/dnotify.h> +#include <linux/statfs.h> +#include <linux/security.h> + +#include <asm/uaccess.h> + +/* some random number */ +#define HUGETLBFS_MAGIC 0x958458f6 + +static struct super_operations hugetlbfs_ops; +static struct address_space_operations hugetlbfs_aops; +struct file_operations hugetlbfs_file_operations; +static struct inode_operations hugetlbfs_dir_inode_operations; +static struct inode_operations hugetlbfs_inode_operations; + +static struct backing_dev_info hugetlbfs_backing_dev_info = { + .ra_pages = 0, /* No readahead */ + .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK, +}; + +int sysctl_hugetlb_shm_group; + +static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct inode *inode = file->f_dentry->d_inode; + struct address_space *mapping = inode->i_mapping; + loff_t len, vma_len; + int ret; + + if ((vma->vm_flags & (VM_MAYSHARE | VM_WRITE)) == VM_WRITE) + return -EINVAL; + + if (vma->vm_pgoff & (HPAGE_SIZE / PAGE_SIZE - 1)) + return -EINVAL; + + if (vma->vm_start & ~HPAGE_MASK) + return -EINVAL; + + if (vma->vm_end & ~HPAGE_MASK) + return -EINVAL; + + if (vma->vm_end - vma->vm_start < HPAGE_SIZE) + return -EINVAL; + + vma_len = (loff_t)(vma->vm_end - vma->vm_start); + + down(&inode->i_sem); + file_accessed(file); + vma->vm_flags |= VM_HUGETLB | VM_RESERVED; + vma->vm_ops = &hugetlb_vm_ops; + + ret = -ENOMEM; + len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); + if (!(vma->vm_flags & VM_WRITE) && len > inode->i_size) + goto out; + + ret = hugetlb_prefault(mapping, vma); + if (ret) + goto out; + + if (inode->i_size < len) + inode->i_size = len; +out: + up(&inode->i_sem); + + return ret; +} + +/* + * Called under down_write(mmap_sem), page_table_lock is not held + */ + +#ifdef HAVE_ARCH_HUGETLB_UNMAPPED_AREA +unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, + unsigned long len, unsigned long pgoff, unsigned long flags); +#else +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; + + if (len & ~HPAGE_MASK) + return -EINVAL; + if (len > TASK_SIZE) + return -ENOMEM; + + if (addr) { + addr = ALIGN(addr, HPAGE_SIZE); + vma = find_vma(mm, addr); + if (TASK_SIZE - len >= addr && + (!vma || addr + len <= vma->vm_start)) + return addr; + } + + start_addr = mm->free_area_cache; + +full_search: + addr = ALIGN(start_addr, HPAGE_SIZE); + + 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, HPAGE_SIZE); + } +} +#endif + +/* + * Read a page. Again trivial. If it didn't already exist + * in the page cache, it is zero-filled. + */ +static int hugetlbfs_readpage(struct file *file, struct page * page) +{ + unlock_page(page); + return -EINVAL; +} + +static int hugetlbfs_prepare_write(struct file *file, + struct page *page, unsigned offset, unsigned to) +{ + return -EINVAL; +} + +static int hugetlbfs_commit_write(struct file *file, + struct page *page, unsigned offset, unsigned to) +{ + return -EINVAL; +} + +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 void truncate_huge_page(struct page *page) +{ + clear_page_dirty(page); + ClearPageUptodate(page); + remove_from_page_cache(page); + put_page(page); +} + +static void truncate_hugepages(struct address_space *mapping, loff_t lstart) +{ + const pgoff_t start = lstart >> HPAGE_SHIFT; + struct pagevec pvec; + pgoff_t next; + int i; + + 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); + hugetlb_put_quota(mapping); + } + huge_pagevec_release(&pvec); + } + BUG_ON(!lstart && mapping->nrpages); +} + +static void hugetlbfs_delete_inode(struct inode *inode) +{ + struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(inode->i_sb); + + hlist_del_init(&inode->i_hash); + list_del_init(&inode->i_list); + list_del_init(&inode->i_sb_list); + inode->i_state |= I_FREEING; + inodes_stat.nr_inodes--; + spin_unlock(&inode_lock); + + if (inode->i_data.nrpages) + truncate_hugepages(&inode->i_data, 0); + + security_inode_delete(inode); + + if (sbinfo->free_inodes >= 0) { + spin_lock(&sbinfo->stat_lock); + sbinfo->free_inodes++; + spin_unlock(&sbinfo->stat_lock); + } + + clear_inode(inode); + destroy_inode(inode); +} + +static void hugetlbfs_forget_inode(struct inode *inode) +{ + struct super_block *super_block = inode->i_sb; + struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(super_block); + + if (hlist_unhashed(&inode->i_hash)) + goto out_truncate; + + if (!(inode->i_state & (I_DIRTY|I_LOCK))) { + list_del(&inode->i_list); + list_add(&inode->i_list, &inode_unused); + } + inodes_stat.nr_unused++; + if (!super_block || (super_block->s_flags & MS_ACTIVE)) { + spin_unlock(&inode_lock); + return; + } + + /* write_inode_now() ? */ + inodes_stat.nr_unused--; + hlist_del_init(&inode->i_hash); +out_truncate: + list_del_init(&inode->i_list); + list_del_init(&inode->i_sb_list); + inode->i_state |= I_FREEING; + inodes_stat.nr_inodes--; + spin_unlock(&inode_lock); + if (inode->i_data.nrpages) + truncate_hugepages(&inode->i_data, 0); + + if (sbinfo->free_inodes >= 0) { + spin_lock(&sbinfo->stat_lock); + sbinfo->free_inodes++; + spin_unlock(&sbinfo->stat_lock); + } + + clear_inode(inode); + destroy_inode(inode); +} + +static void hugetlbfs_drop_inode(struct inode *inode) +{ + if (!inode->i_nlink) + hugetlbfs_delete_inode(inode); + else + hugetlbfs_forget_inode(inode); +} + +/* + * h_pgoff is in HPAGE_SIZE units. + * vma->vm_pgoff is in PAGE_SIZE units. + */ +static inline void +hugetlb_vmtruncate_list(struct prio_tree_root *root, unsigned long h_pgoff) +{ + struct vm_area_struct *vma; + struct prio_tree_iter iter; + + vma_prio_tree_foreach(vma, &iter, root, h_pgoff, ULONG_MAX) { + unsigned long h_vm_pgoff; + unsigned long v_length; + unsigned long v_offset; + + h_vm_pgoff = vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT); + v_offset = (h_pgoff - h_vm_pgoff) << HPAGE_SHIFT; + /* + * Is this VMA fully outside the truncation point? + */ + if (h_vm_pgoff >= h_pgoff) + v_offset = 0; + + v_length = vma->vm_end - vma->vm_start; + + zap_hugepage_range(vma, + vma->vm_start + v_offset, + v_length - v_offset); + } +} + +/* + * Expanding truncates are not allowed. + */ +static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) +{ + unsigned long pgoff; + struct address_space *mapping = inode->i_mapping; + + if (offset > inode->i_size) + return -EINVAL; + + BUG_ON(offset & ~HPAGE_MASK); + pgoff = offset >> HPAGE_SHIFT; + + inode->i_size = offset; + spin_lock(&mapping->i_mmap_lock); + if (!prio_tree_empty(&mapping->i_mmap)) + hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff); + spin_unlock(&mapping->i_mmap_lock); + truncate_hugepages(mapping, offset); + return 0; +} + +static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) +{ + struct inode *inode = dentry->d_inode; + int error; + unsigned int ia_valid = attr->ia_valid; + + BUG_ON(!inode); + + error = inode_change_ok(inode, attr); + if (error) + goto out; + + if (ia_valid & ATTR_SIZE) { + error = -EINVAL; + if (!(attr->ia_size & ~HPAGE_MASK)) + error = hugetlb_vmtruncate(inode, attr->ia_size); + if (error) + goto out; + attr->ia_valid &= ~ATTR_SIZE; + } + error = inode_setattr(inode, attr); +out: + return error; +} + +static struct inode *hugetlbfs_get_inode(struct super_block *sb, uid_t uid, + gid_t gid, int mode, dev_t dev) +{ + struct inode *inode; + struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb); + + if (sbinfo->free_inodes >= 0) { + spin_lock(&sbinfo->stat_lock); + if (!sbinfo->free_inodes) { + spin_unlock(&sbinfo->stat_lock); + return NULL; + } + sbinfo->free_inodes--; + spin_unlock(&sbinfo->stat_lock); + } + + inode = new_inode(sb); + if (inode) { + struct hugetlbfs_inode_info *info; + inode->i_mode = mode; + inode->i_uid = uid; + inode->i_gid = gid; + inode->i_blksize = HPAGE_SIZE; + inode->i_blocks = 0; + 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; + info = HUGETLBFS_I(inode); + mpol_shared_policy_init(&info->policy); + 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) */ + inode->i_nlink++; + break; + case S_IFLNK: + inode->i_op = &page_symlink_inode_operations; + break; + } + } + return inode; +} + +/* + * File creation. Allocate an inode, and we're done.. + */ +static int hugetlbfs_mknod(struct inode *dir, + struct dentry *dentry, int 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, int mode) +{ + int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0); + if (!retval) + dir->i_nlink++; + return retval; +} + +static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, int 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; +} + +/* + * For direct-IO reads into hugetlb pages + */ +static int hugetlbfs_set_page_dirty(struct page *page) +{ + return 0; +} + +static int hugetlbfs_statfs(struct super_block *sb, struct kstatfs *buf) +{ + struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb); + + buf->f_type = HUGETLBFS_MAGIC; + buf->f_bsize = HPAGE_SIZE; + if (sbinfo) { + spin_lock(&sbinfo->stat_lock); + 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 kmem_cache_t *hugetlbfs_inode_cachep; + +static struct inode *hugetlbfs_alloc_inode(struct super_block *sb) +{ + struct hugetlbfs_inode_info *p; + + p = kmem_cache_alloc(hugetlbfs_inode_cachep, SLAB_KERNEL); + if (!p) + return NULL; + return &p->vfs_inode; +} + +static void init_once(void *foo, kmem_cache_t *cachep, unsigned long flags) +{ + struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo; + + if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == + SLAB_CTOR_CONSTRUCTOR) + inode_init_once(&ei->vfs_inode); +} + +static void hugetlbfs_destroy_inode(struct inode *inode) +{ + mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy); + kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode)); +} + +static struct address_space_operations hugetlbfs_aops = { + .readpage = hugetlbfs_readpage, + .prepare_write = hugetlbfs_prepare_write, + .commit_write = hugetlbfs_commit_write, + .set_page_dirty = hugetlbfs_set_page_dirty, +}; + +struct file_operations hugetlbfs_file_operations = { + .mmap = hugetlbfs_file_mmap, + .fsync = simple_sync_file, + .get_unmapped_area = hugetlb_get_unmapped_area, +}; + +static 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 struct inode_operations hugetlbfs_inode_operations = { + .setattr = hugetlbfs_setattr, +}; + +static struct super_operations hugetlbfs_ops = { + .alloc_inode = hugetlbfs_alloc_inode, + .destroy_inode = hugetlbfs_destroy_inode, + .statfs = hugetlbfs_statfs, + .drop_inode = hugetlbfs_drop_inode, + .put_super = hugetlbfs_put_super, +}; + +static int +hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) +{ + char *opt, *value, *rest; + + if (!options) + return 0; + while ((opt = strsep(&options, ",")) != NULL) { + if (!*opt) + continue; + + value = strchr(opt, '='); + if (!value || !*value) + return -EINVAL; + else + *value++ = '\0'; + + if (!strcmp(opt, "uid")) + pconfig->uid = simple_strtoul(value, &value, 0); + else if (!strcmp(opt, "gid")) + pconfig->gid = simple_strtoul(value, &value, 0); + else if (!strcmp(opt, "mode")) + pconfig->mode = simple_strtoul(value,&value,0) & 0777U; + else if (!strcmp(opt, "size")) { + unsigned long long size = memparse(value, &rest); + if (*rest == '%') { + size <<= HPAGE_SHIFT; + size *= max_huge_pages; + do_div(size, 100); + rest++; + } + size &= HPAGE_MASK; + pconfig->nr_blocks = (size >> HPAGE_SHIFT); + value = rest; + } else if (!strcmp(opt,"nr_inodes")) { + pconfig->nr_inodes = memparse(value, &rest); + value = rest; + } else + return -EINVAL; + + if (*value) + return -EINVAL; + } + return 0; +} + +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; + + 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; + 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; + 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 = HPAGE_SIZE; + sb->s_blocksize_bits = HPAGE_SHIFT; + 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) +{ + 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 > 0) + sbinfo->free_blocks--; + else + ret = -ENOMEM; + spin_unlock(&sbinfo->stat_lock); + } + + return ret; +} + +void hugetlb_put_quota(struct address_space *mapping) +{ + struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); + + if (sbinfo->free_blocks > -1) { + spin_lock(&sbinfo->stat_lock); + sbinfo->free_blocks++; + spin_unlock(&sbinfo->stat_lock); + } +} + +static struct super_block *hugetlbfs_get_sb(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return get_sb_nodev(fs_type, flags, data, hugetlbfs_fill_super); +} + +static struct file_system_type hugetlbfs_fs_type = { + .name = "hugetlbfs", + .get_sb = hugetlbfs_get_sb, + .kill_sb = kill_litter_super, +}; + +static struct vfsmount *hugetlbfs_vfsmount; + +/* + * Return the next identifier for a shm file + */ +static unsigned long hugetlbfs_counter(void) +{ + static DEFINE_SPINLOCK(lock); + static unsigned long counter; + unsigned long ret; + + spin_lock(&lock); + ret = ++counter; + spin_unlock(&lock); + return ret; +} + +static int can_do_hugetlb_shm(void) +{ + return likely(capable(CAP_IPC_LOCK) || + in_group_p(sysctl_hugetlb_shm_group) || + can_do_mlock()); +} + +struct file *hugetlb_zero_setup(size_t size) +{ + int error = -ENOMEM; + struct file *file; + struct inode *inode; + struct dentry *dentry, *root; + struct qstr quick_string; + char buf[16]; + + if (!can_do_hugetlb_shm()) + return ERR_PTR(-EPERM); + + if (!is_hugepage_mem_enough(size)) + return ERR_PTR(-ENOMEM); + + if (!user_shm_lock(size, current->user)) + return ERR_PTR(-ENOMEM); + + root = hugetlbfs_vfsmount->mnt_root; + snprintf(buf, 16, "%lu", hugetlbfs_counter()); + quick_string.name = buf; + quick_string.len = strlen(quick_string.name); + quick_string.hash = 0; + dentry = d_alloc(root, &quick_string); + if (!dentry) + goto out_shm_unlock; + + error = -ENFILE; + file = get_empty_filp(); + if (!file) + goto out_dentry; + + error = -ENOSPC; + inode = hugetlbfs_get_inode(root->d_sb, current->fsuid, + current->fsgid, S_IFREG | S_IRWXUGO, 0); + if (!inode) + goto out_file; + + d_instantiate(dentry, inode); + inode->i_size = size; + inode->i_nlink = 0; + file->f_vfsmnt = mntget(hugetlbfs_vfsmount); + file->f_dentry = dentry; + file->f_mapping = inode->i_mapping; + file->f_op = &hugetlbfs_file_operations; + file->f_mode = FMODE_WRITE | FMODE_READ; + return file; + +out_file: + put_filp(file); +out_dentry: + dput(dentry); +out_shm_unlock: + user_shm_unlock(size, current->user); + return ERR_PTR(error); +} + +static int __init init_hugetlbfs_fs(void) +{ + int error; + struct vfsmount *vfsmount; + + hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache", + sizeof(struct hugetlbfs_inode_info), + 0, 0, init_once, NULL); + if (hugetlbfs_inode_cachep == NULL) + return -ENOMEM; + + 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); + return error; +} + +static void __exit exit_hugetlbfs_fs(void) +{ + kmem_cache_destroy(hugetlbfs_inode_cachep); + unregister_filesystem(&hugetlbfs_fs_type); +} + +module_init(init_hugetlbfs_fs) +module_exit(exit_hugetlbfs_fs) + +MODULE_LICENSE("GPL"); |