11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * hugetlbpage-backed filesystem. Based on ramfs. 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * William Irwin, 2002 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * Copyright (C) 2002 Linus Torvalds. 71da177e4SLinus Torvalds */ 81da177e4SLinus Torvalds 91da177e4SLinus Torvalds #include <linux/module.h> 101da177e4SLinus Torvalds #include <linux/thread_info.h> 111da177e4SLinus Torvalds #include <asm/current.h> 121da177e4SLinus Torvalds #include <linux/sched.h> /* remove ASAP */ 131da177e4SLinus Torvalds #include <linux/fs.h> 141da177e4SLinus Torvalds #include <linux/mount.h> 151da177e4SLinus Torvalds #include <linux/file.h> 16e73a75faSRandy Dunlap #include <linux/kernel.h> 171da177e4SLinus Torvalds #include <linux/writeback.h> 181da177e4SLinus Torvalds #include <linux/pagemap.h> 191da177e4SLinus Torvalds #include <linux/highmem.h> 201da177e4SLinus Torvalds #include <linux/init.h> 211da177e4SLinus Torvalds #include <linux/string.h> 2216f7e0feSRandy Dunlap #include <linux/capability.h> 23e73a75faSRandy Dunlap #include <linux/ctype.h> 241da177e4SLinus Torvalds #include <linux/backing-dev.h> 251da177e4SLinus Torvalds #include <linux/hugetlb.h> 261da177e4SLinus Torvalds #include <linux/pagevec.h> 27e73a75faSRandy Dunlap #include <linux/parser.h> 28036e0856SBenjamin Herrenschmidt #include <linux/mman.h> 291da177e4SLinus Torvalds #include <linux/quotaops.h> 301da177e4SLinus Torvalds #include <linux/slab.h> 311da177e4SLinus Torvalds #include <linux/dnotify.h> 321da177e4SLinus Torvalds #include <linux/statfs.h> 331da177e4SLinus Torvalds #include <linux/security.h> 341da177e4SLinus Torvalds 351da177e4SLinus Torvalds #include <asm/uaccess.h> 361da177e4SLinus Torvalds 371da177e4SLinus Torvalds /* some random number */ 381da177e4SLinus Torvalds #define HUGETLBFS_MAGIC 0x958458f6 391da177e4SLinus Torvalds 40ee9b6d61SJosef 'Jeff' Sipek static const struct super_operations hugetlbfs_ops; 41f5e54d6eSChristoph Hellwig static const struct address_space_operations hugetlbfs_aops; 424b6f5d20SArjan van de Ven const struct file_operations hugetlbfs_file_operations; 4392e1d5beSArjan van de Ven static const struct inode_operations hugetlbfs_dir_inode_operations; 4492e1d5beSArjan van de Ven static const struct inode_operations hugetlbfs_inode_operations; 451da177e4SLinus Torvalds 461da177e4SLinus Torvalds static struct backing_dev_info hugetlbfs_backing_dev_info = { 471da177e4SLinus Torvalds .ra_pages = 0, /* No readahead */ 481da177e4SLinus Torvalds .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK, 491da177e4SLinus Torvalds }; 501da177e4SLinus Torvalds 511da177e4SLinus Torvalds int sysctl_hugetlb_shm_group; 521da177e4SLinus Torvalds 53e73a75faSRandy Dunlap enum { 54e73a75faSRandy Dunlap Opt_size, Opt_nr_inodes, 55e73a75faSRandy Dunlap Opt_mode, Opt_uid, Opt_gid, 56e73a75faSRandy Dunlap Opt_err, 57e73a75faSRandy Dunlap }; 58e73a75faSRandy Dunlap 59e73a75faSRandy Dunlap static match_table_t tokens = { 60e73a75faSRandy Dunlap {Opt_size, "size=%s"}, 61e73a75faSRandy Dunlap {Opt_nr_inodes, "nr_inodes=%s"}, 62e73a75faSRandy Dunlap {Opt_mode, "mode=%o"}, 63e73a75faSRandy Dunlap {Opt_uid, "uid=%u"}, 64e73a75faSRandy Dunlap {Opt_gid, "gid=%u"}, 65e73a75faSRandy Dunlap {Opt_err, NULL}, 66e73a75faSRandy Dunlap }; 67e73a75faSRandy Dunlap 682e9b367cSAdam Litke static void huge_pagevec_release(struct pagevec *pvec) 692e9b367cSAdam Litke { 702e9b367cSAdam Litke int i; 712e9b367cSAdam Litke 722e9b367cSAdam Litke for (i = 0; i < pagevec_count(pvec); ++i) 732e9b367cSAdam Litke put_page(pvec->pages[i]); 742e9b367cSAdam Litke 752e9b367cSAdam Litke pagevec_reinit(pvec); 762e9b367cSAdam Litke } 772e9b367cSAdam Litke 781da177e4SLinus Torvalds static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) 791da177e4SLinus Torvalds { 80b39424e2SJosef Sipek struct inode *inode = file->f_path.dentry->d_inode; 811da177e4SLinus Torvalds loff_t len, vma_len; 821da177e4SLinus Torvalds int ret; 831da177e4SLinus Torvalds 8468589bc3SHugh Dickins /* 85dec4ad86SDavid Gibson * vma address alignment (but not the pgoff alignment) has 86dec4ad86SDavid Gibson * already been checked by prepare_hugepage_range. If you add 87dec4ad86SDavid Gibson * any error returns here, do so after setting VM_HUGETLB, so 88dec4ad86SDavid Gibson * is_vm_hugetlb_page tests below unmap_region go the right 89dec4ad86SDavid Gibson * way when do_mmap_pgoff unwinds (may be important on powerpc 90dec4ad86SDavid Gibson * and ia64). 9168589bc3SHugh Dickins */ 9268589bc3SHugh Dickins vma->vm_flags |= VM_HUGETLB | VM_RESERVED; 9368589bc3SHugh Dickins vma->vm_ops = &hugetlb_vm_ops; 941da177e4SLinus Torvalds 95dec4ad86SDavid Gibson if (vma->vm_pgoff & ~(HPAGE_MASK >> PAGE_SHIFT)) 96dec4ad86SDavid Gibson return -EINVAL; 97dec4ad86SDavid Gibson 981da177e4SLinus Torvalds vma_len = (loff_t)(vma->vm_end - vma->vm_start); 991da177e4SLinus Torvalds 1001b1dcc1bSJes Sorensen mutex_lock(&inode->i_mutex); 1011da177e4SLinus Torvalds file_accessed(file); 1021da177e4SLinus Torvalds 1031da177e4SLinus Torvalds ret = -ENOMEM; 1041da177e4SLinus Torvalds len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); 1051da177e4SLinus Torvalds 106a43a8c39SChen, Kenneth W if (vma->vm_flags & VM_MAYSHARE && 107a43a8c39SChen, Kenneth W hugetlb_reserve_pages(inode, vma->vm_pgoff >> (HPAGE_SHIFT-PAGE_SHIFT), 108a43a8c39SChen, Kenneth W len >> HPAGE_SHIFT)) 109b45b5bd6SDavid Gibson goto out; 110b45b5bd6SDavid Gibson 1114c887265SAdam Litke ret = 0; 1124c887265SAdam Litke hugetlb_prefault_arch_hook(vma->vm_mm); 113b6174df5SZhang, Yanmin if (vma->vm_flags & VM_WRITE && inode->i_size < len) 1141da177e4SLinus Torvalds inode->i_size = len; 1151da177e4SLinus Torvalds out: 1161b1dcc1bSJes Sorensen mutex_unlock(&inode->i_mutex); 1171da177e4SLinus Torvalds 1181da177e4SLinus Torvalds return ret; 1191da177e4SLinus Torvalds } 1201da177e4SLinus Torvalds 1211da177e4SLinus Torvalds /* 122508034a3SHugh Dickins * Called under down_write(mmap_sem). 1231da177e4SLinus Torvalds */ 1241da177e4SLinus Torvalds 125d2ba27e8SAdrian Bunk #ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA 1261da177e4SLinus Torvalds static unsigned long 1271da177e4SLinus Torvalds hugetlb_get_unmapped_area(struct file *file, unsigned long addr, 1281da177e4SLinus Torvalds unsigned long len, unsigned long pgoff, unsigned long flags) 1291da177e4SLinus Torvalds { 1301da177e4SLinus Torvalds struct mm_struct *mm = current->mm; 1311da177e4SLinus Torvalds struct vm_area_struct *vma; 1321da177e4SLinus Torvalds unsigned long start_addr; 1331da177e4SLinus Torvalds 1341da177e4SLinus Torvalds if (len & ~HPAGE_MASK) 1351da177e4SLinus Torvalds return -EINVAL; 1361da177e4SLinus Torvalds if (len > TASK_SIZE) 1371da177e4SLinus Torvalds return -ENOMEM; 1381da177e4SLinus Torvalds 139036e0856SBenjamin Herrenschmidt if (flags & MAP_FIXED) { 140dec4ad86SDavid Gibson if (prepare_hugepage_range(addr, len)) 141036e0856SBenjamin Herrenschmidt return -EINVAL; 142036e0856SBenjamin Herrenschmidt return addr; 143036e0856SBenjamin Herrenschmidt } 144036e0856SBenjamin Herrenschmidt 1451da177e4SLinus Torvalds if (addr) { 1461da177e4SLinus Torvalds addr = ALIGN(addr, HPAGE_SIZE); 1471da177e4SLinus Torvalds vma = find_vma(mm, addr); 1481da177e4SLinus Torvalds if (TASK_SIZE - len >= addr && 1491da177e4SLinus Torvalds (!vma || addr + len <= vma->vm_start)) 1501da177e4SLinus Torvalds return addr; 1511da177e4SLinus Torvalds } 1521da177e4SLinus Torvalds 1531da177e4SLinus Torvalds start_addr = mm->free_area_cache; 1541da177e4SLinus Torvalds 1551363c3cdSWolfgang Wander if (len <= mm->cached_hole_size) 1561363c3cdSWolfgang Wander start_addr = TASK_UNMAPPED_BASE; 1571363c3cdSWolfgang Wander 1581da177e4SLinus Torvalds full_search: 1591da177e4SLinus Torvalds addr = ALIGN(start_addr, HPAGE_SIZE); 1601da177e4SLinus Torvalds 1611da177e4SLinus Torvalds for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { 1621da177e4SLinus Torvalds /* At this point: (!vma || addr < vma->vm_end). */ 1631da177e4SLinus Torvalds if (TASK_SIZE - len < addr) { 1641da177e4SLinus Torvalds /* 1651da177e4SLinus Torvalds * Start a new search - just in case we missed 1661da177e4SLinus Torvalds * some holes. 1671da177e4SLinus Torvalds */ 1681da177e4SLinus Torvalds if (start_addr != TASK_UNMAPPED_BASE) { 1691da177e4SLinus Torvalds start_addr = TASK_UNMAPPED_BASE; 1701da177e4SLinus Torvalds goto full_search; 1711da177e4SLinus Torvalds } 1721da177e4SLinus Torvalds return -ENOMEM; 1731da177e4SLinus Torvalds } 1741da177e4SLinus Torvalds 1751da177e4SLinus Torvalds if (!vma || addr + len <= vma->vm_start) 1761da177e4SLinus Torvalds return addr; 1771da177e4SLinus Torvalds addr = ALIGN(vma->vm_end, HPAGE_SIZE); 1781da177e4SLinus Torvalds } 1791da177e4SLinus Torvalds } 1801da177e4SLinus Torvalds #endif 1811da177e4SLinus Torvalds 1821da177e4SLinus Torvalds /* 1831da177e4SLinus Torvalds * Read a page. Again trivial. If it didn't already exist 1841da177e4SLinus Torvalds * in the page cache, it is zero-filled. 1851da177e4SLinus Torvalds */ 1861da177e4SLinus Torvalds static int hugetlbfs_readpage(struct file *file, struct page * page) 1871da177e4SLinus Torvalds { 1881da177e4SLinus Torvalds unlock_page(page); 1891da177e4SLinus Torvalds return -EINVAL; 1901da177e4SLinus Torvalds } 1911da177e4SLinus Torvalds 192800d15a5SNick Piggin static int hugetlbfs_write_begin(struct file *file, 193800d15a5SNick Piggin struct address_space *mapping, 194800d15a5SNick Piggin loff_t pos, unsigned len, unsigned flags, 195800d15a5SNick Piggin struct page **pagep, void **fsdata) 1961da177e4SLinus Torvalds { 1971da177e4SLinus Torvalds return -EINVAL; 1981da177e4SLinus Torvalds } 1991da177e4SLinus Torvalds 200800d15a5SNick Piggin static int hugetlbfs_write_end(struct file *file, struct address_space *mapping, 201800d15a5SNick Piggin loff_t pos, unsigned len, unsigned copied, 202800d15a5SNick Piggin struct page *page, void *fsdata) 2031da177e4SLinus Torvalds { 204800d15a5SNick Piggin BUG(); 2051da177e4SLinus Torvalds return -EINVAL; 2061da177e4SLinus Torvalds } 2071da177e4SLinus Torvalds 2081da177e4SLinus Torvalds static void truncate_huge_page(struct page *page) 2091da177e4SLinus Torvalds { 210fba2591bSLinus Torvalds cancel_dirty_page(page, /* No IO accounting for huge pages? */0); 2111da177e4SLinus Torvalds ClearPageUptodate(page); 2121da177e4SLinus Torvalds remove_from_page_cache(page); 2131da177e4SLinus Torvalds put_page(page); 2141da177e4SLinus Torvalds } 2151da177e4SLinus Torvalds 216b45b5bd6SDavid Gibson static void truncate_hugepages(struct inode *inode, loff_t lstart) 2171da177e4SLinus Torvalds { 218b45b5bd6SDavid Gibson struct address_space *mapping = &inode->i_data; 2191da177e4SLinus Torvalds const pgoff_t start = lstart >> HPAGE_SHIFT; 2201da177e4SLinus Torvalds struct pagevec pvec; 2211da177e4SLinus Torvalds pgoff_t next; 222a43a8c39SChen, Kenneth W int i, freed = 0; 2231da177e4SLinus Torvalds 2241da177e4SLinus Torvalds pagevec_init(&pvec, 0); 2251da177e4SLinus Torvalds next = start; 2261da177e4SLinus Torvalds while (1) { 2271da177e4SLinus Torvalds if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { 2281da177e4SLinus Torvalds if (next == start) 2291da177e4SLinus Torvalds break; 2301da177e4SLinus Torvalds next = start; 2311da177e4SLinus Torvalds continue; 2321da177e4SLinus Torvalds } 2331da177e4SLinus Torvalds 2341da177e4SLinus Torvalds for (i = 0; i < pagevec_count(&pvec); ++i) { 2351da177e4SLinus Torvalds struct page *page = pvec.pages[i]; 2361da177e4SLinus Torvalds 2371da177e4SLinus Torvalds lock_page(page); 2381da177e4SLinus Torvalds if (page->index > next) 2391da177e4SLinus Torvalds next = page->index; 2401da177e4SLinus Torvalds ++next; 2411da177e4SLinus Torvalds truncate_huge_page(page); 2421da177e4SLinus Torvalds unlock_page(page); 2431da177e4SLinus Torvalds hugetlb_put_quota(mapping); 244a43a8c39SChen, Kenneth W freed++; 2451da177e4SLinus Torvalds } 2461da177e4SLinus Torvalds huge_pagevec_release(&pvec); 2471da177e4SLinus Torvalds } 2481da177e4SLinus Torvalds BUG_ON(!lstart && mapping->nrpages); 249a43a8c39SChen, Kenneth W hugetlb_unreserve_pages(inode, start, freed); 2501da177e4SLinus Torvalds } 2511da177e4SLinus Torvalds 2521da177e4SLinus Torvalds static void hugetlbfs_delete_inode(struct inode *inode) 2531da177e4SLinus Torvalds { 254b45b5bd6SDavid Gibson truncate_hugepages(inode, 0); 255149f4211SChristoph Hellwig clear_inode(inode); 256149f4211SChristoph Hellwig } 257149f4211SChristoph Hellwig 258ddc0a51dSJosh Triplett static void hugetlbfs_forget_inode(struct inode *inode) __releases(inode_lock) 2591da177e4SLinus Torvalds { 2600b1533f6SChristoph Hellwig struct super_block *sb = inode->i_sb; 2611da177e4SLinus Torvalds 2620b1533f6SChristoph Hellwig if (!hlist_unhashed(&inode->i_hash)) { 2630b1533f6SChristoph Hellwig if (!(inode->i_state & (I_DIRTY|I_LOCK))) 2640b1533f6SChristoph Hellwig list_move(&inode->i_list, &inode_unused); 2651da177e4SLinus Torvalds inodes_stat.nr_unused++; 2660b1533f6SChristoph Hellwig if (!sb || (sb->s_flags & MS_ACTIVE)) { 2671da177e4SLinus Torvalds spin_unlock(&inode_lock); 2681da177e4SLinus Torvalds return; 2691da177e4SLinus Torvalds } 2700b1533f6SChristoph Hellwig inode->i_state |= I_WILL_FREE; 2710b1533f6SChristoph Hellwig spin_unlock(&inode_lock); 2720b1533f6SChristoph Hellwig /* 2730b1533f6SChristoph Hellwig * write_inode_now is a noop as we set BDI_CAP_NO_WRITEBACK 2740b1533f6SChristoph Hellwig * in our backing_dev_info. 2750b1533f6SChristoph Hellwig */ 2760b1533f6SChristoph Hellwig write_inode_now(inode, 1); 2770b1533f6SChristoph Hellwig spin_lock(&inode_lock); 2780b1533f6SChristoph Hellwig inode->i_state &= ~I_WILL_FREE; 2791da177e4SLinus Torvalds inodes_stat.nr_unused--; 2801da177e4SLinus Torvalds hlist_del_init(&inode->i_hash); 2810b1533f6SChristoph Hellwig } 2821da177e4SLinus Torvalds list_del_init(&inode->i_list); 2831da177e4SLinus Torvalds list_del_init(&inode->i_sb_list); 2841da177e4SLinus Torvalds inode->i_state |= I_FREEING; 2851da177e4SLinus Torvalds inodes_stat.nr_inodes--; 2861da177e4SLinus Torvalds spin_unlock(&inode_lock); 287b45b5bd6SDavid Gibson truncate_hugepages(inode, 0); 2881da177e4SLinus Torvalds clear_inode(inode); 2891da177e4SLinus Torvalds destroy_inode(inode); 2901da177e4SLinus Torvalds } 2911da177e4SLinus Torvalds 2921da177e4SLinus Torvalds static void hugetlbfs_drop_inode(struct inode *inode) 2931da177e4SLinus Torvalds { 2941da177e4SLinus Torvalds if (!inode->i_nlink) 2956b09b9dfSChristoph Hellwig generic_delete_inode(inode); 2961da177e4SLinus Torvalds else 2971da177e4SLinus Torvalds hugetlbfs_forget_inode(inode); 2981da177e4SLinus Torvalds } 2991da177e4SLinus Torvalds 3001da177e4SLinus Torvalds static inline void 301856fc295SHugh Dickins hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff) 3021da177e4SLinus Torvalds { 3031da177e4SLinus Torvalds struct vm_area_struct *vma; 3041da177e4SLinus Torvalds struct prio_tree_iter iter; 3051da177e4SLinus Torvalds 306856fc295SHugh Dickins vma_prio_tree_foreach(vma, &iter, root, pgoff, ULONG_MAX) { 3071da177e4SLinus Torvalds unsigned long v_offset; 3081da177e4SLinus Torvalds 3091da177e4SLinus Torvalds /* 310856fc295SHugh Dickins * Can the expression below overflow on 32-bit arches? 311856fc295SHugh Dickins * No, because the prio_tree returns us only those vmas 312856fc295SHugh Dickins * which overlap the truncated area starting at pgoff, 313856fc295SHugh Dickins * and no vma on a 32-bit arch can span beyond the 4GB. 3141da177e4SLinus Torvalds */ 315856fc295SHugh Dickins if (vma->vm_pgoff < pgoff) 316856fc295SHugh Dickins v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT; 317856fc295SHugh Dickins else 3181da177e4SLinus Torvalds v_offset = 0; 3191da177e4SLinus Torvalds 320502717f4SChen, Kenneth W __unmap_hugepage_range(vma, 321508034a3SHugh Dickins vma->vm_start + v_offset, vma->vm_end); 3221da177e4SLinus Torvalds } 3231da177e4SLinus Torvalds } 3241da177e4SLinus Torvalds 3251da177e4SLinus Torvalds static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) 3261da177e4SLinus Torvalds { 327856fc295SHugh Dickins pgoff_t pgoff; 3281da177e4SLinus Torvalds struct address_space *mapping = inode->i_mapping; 3291da177e4SLinus Torvalds 3301da177e4SLinus Torvalds BUG_ON(offset & ~HPAGE_MASK); 331856fc295SHugh Dickins pgoff = offset >> PAGE_SHIFT; 3321da177e4SLinus Torvalds 3337aa91e10SKen Chen i_size_write(inode, offset); 3341da177e4SLinus Torvalds spin_lock(&mapping->i_mmap_lock); 3351da177e4SLinus Torvalds if (!prio_tree_empty(&mapping->i_mmap)) 3361da177e4SLinus Torvalds hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff); 3371da177e4SLinus Torvalds spin_unlock(&mapping->i_mmap_lock); 338b45b5bd6SDavid Gibson truncate_hugepages(inode, offset); 3391da177e4SLinus Torvalds return 0; 3401da177e4SLinus Torvalds } 3411da177e4SLinus Torvalds 3421da177e4SLinus Torvalds static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) 3431da177e4SLinus Torvalds { 3441da177e4SLinus Torvalds struct inode *inode = dentry->d_inode; 3451da177e4SLinus Torvalds int error; 3461da177e4SLinus Torvalds unsigned int ia_valid = attr->ia_valid; 3471da177e4SLinus Torvalds 3481da177e4SLinus Torvalds BUG_ON(!inode); 3491da177e4SLinus Torvalds 3501da177e4SLinus Torvalds error = inode_change_ok(inode, attr); 3511da177e4SLinus Torvalds if (error) 3521da177e4SLinus Torvalds goto out; 3531da177e4SLinus Torvalds 3541da177e4SLinus Torvalds if (ia_valid & ATTR_SIZE) { 3551da177e4SLinus Torvalds error = -EINVAL; 3561da177e4SLinus Torvalds if (!(attr->ia_size & ~HPAGE_MASK)) 3571da177e4SLinus Torvalds error = hugetlb_vmtruncate(inode, attr->ia_size); 3581da177e4SLinus Torvalds if (error) 3591da177e4SLinus Torvalds goto out; 3601da177e4SLinus Torvalds attr->ia_valid &= ~ATTR_SIZE; 3611da177e4SLinus Torvalds } 3621da177e4SLinus Torvalds error = inode_setattr(inode, attr); 3631da177e4SLinus Torvalds out: 3641da177e4SLinus Torvalds return error; 3651da177e4SLinus Torvalds } 3661da177e4SLinus Torvalds 3671da177e4SLinus Torvalds static struct inode *hugetlbfs_get_inode(struct super_block *sb, uid_t uid, 3681da177e4SLinus Torvalds gid_t gid, int mode, dev_t dev) 3691da177e4SLinus Torvalds { 3701da177e4SLinus Torvalds struct inode *inode; 3711da177e4SLinus Torvalds 3721da177e4SLinus Torvalds inode = new_inode(sb); 3731da177e4SLinus Torvalds if (inode) { 3741da177e4SLinus Torvalds struct hugetlbfs_inode_info *info; 3751da177e4SLinus Torvalds inode->i_mode = mode; 3761da177e4SLinus Torvalds inode->i_uid = uid; 3771da177e4SLinus Torvalds inode->i_gid = gid; 3781da177e4SLinus Torvalds inode->i_blocks = 0; 3791da177e4SLinus Torvalds inode->i_mapping->a_ops = &hugetlbfs_aops; 3801da177e4SLinus Torvalds inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info; 3811da177e4SLinus Torvalds inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; 382a43a8c39SChen, Kenneth W INIT_LIST_HEAD(&inode->i_mapping->private_list); 3831da177e4SLinus Torvalds info = HUGETLBFS_I(inode); 3847339ff83SRobin Holt mpol_shared_policy_init(&info->policy, MPOL_DEFAULT, NULL); 3851da177e4SLinus Torvalds switch (mode & S_IFMT) { 3861da177e4SLinus Torvalds default: 3871da177e4SLinus Torvalds init_special_inode(inode, mode, dev); 3881da177e4SLinus Torvalds break; 3891da177e4SLinus Torvalds case S_IFREG: 3901da177e4SLinus Torvalds inode->i_op = &hugetlbfs_inode_operations; 3911da177e4SLinus Torvalds inode->i_fop = &hugetlbfs_file_operations; 3921da177e4SLinus Torvalds break; 3931da177e4SLinus Torvalds case S_IFDIR: 3941da177e4SLinus Torvalds inode->i_op = &hugetlbfs_dir_inode_operations; 3951da177e4SLinus Torvalds inode->i_fop = &simple_dir_operations; 3961da177e4SLinus Torvalds 3971da177e4SLinus Torvalds /* directory inodes start off with i_nlink == 2 (for "." entry) */ 398d8c76e6fSDave Hansen inc_nlink(inode); 3991da177e4SLinus Torvalds break; 4001da177e4SLinus Torvalds case S_IFLNK: 4011da177e4SLinus Torvalds inode->i_op = &page_symlink_inode_operations; 4021da177e4SLinus Torvalds break; 4031da177e4SLinus Torvalds } 4041da177e4SLinus Torvalds } 4051da177e4SLinus Torvalds return inode; 4061da177e4SLinus Torvalds } 4071da177e4SLinus Torvalds 4081da177e4SLinus Torvalds /* 4091da177e4SLinus Torvalds * File creation. Allocate an inode, and we're done.. 4101da177e4SLinus Torvalds */ 4111da177e4SLinus Torvalds static int hugetlbfs_mknod(struct inode *dir, 4121da177e4SLinus Torvalds struct dentry *dentry, int mode, dev_t dev) 4131da177e4SLinus Torvalds { 4141da177e4SLinus Torvalds struct inode *inode; 4151da177e4SLinus Torvalds int error = -ENOSPC; 4161da177e4SLinus Torvalds gid_t gid; 4171da177e4SLinus Torvalds 4181da177e4SLinus Torvalds if (dir->i_mode & S_ISGID) { 4191da177e4SLinus Torvalds gid = dir->i_gid; 4201da177e4SLinus Torvalds if (S_ISDIR(mode)) 4211da177e4SLinus Torvalds mode |= S_ISGID; 4221da177e4SLinus Torvalds } else { 4231da177e4SLinus Torvalds gid = current->fsgid; 4241da177e4SLinus Torvalds } 4251da177e4SLinus Torvalds inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, gid, mode, dev); 4261da177e4SLinus Torvalds if (inode) { 4271da177e4SLinus Torvalds dir->i_ctime = dir->i_mtime = CURRENT_TIME; 4281da177e4SLinus Torvalds d_instantiate(dentry, inode); 4291da177e4SLinus Torvalds dget(dentry); /* Extra count - pin the dentry in core */ 4301da177e4SLinus Torvalds error = 0; 4311da177e4SLinus Torvalds } 4321da177e4SLinus Torvalds return error; 4331da177e4SLinus Torvalds } 4341da177e4SLinus Torvalds 4351da177e4SLinus Torvalds static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) 4361da177e4SLinus Torvalds { 4371da177e4SLinus Torvalds int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0); 4381da177e4SLinus Torvalds if (!retval) 439d8c76e6fSDave Hansen inc_nlink(dir); 4401da177e4SLinus Torvalds return retval; 4411da177e4SLinus Torvalds } 4421da177e4SLinus Torvalds 4431da177e4SLinus Torvalds static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd) 4441da177e4SLinus Torvalds { 4451da177e4SLinus Torvalds return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0); 4461da177e4SLinus Torvalds } 4471da177e4SLinus Torvalds 4481da177e4SLinus Torvalds static int hugetlbfs_symlink(struct inode *dir, 4491da177e4SLinus Torvalds struct dentry *dentry, const char *symname) 4501da177e4SLinus Torvalds { 4511da177e4SLinus Torvalds struct inode *inode; 4521da177e4SLinus Torvalds int error = -ENOSPC; 4531da177e4SLinus Torvalds gid_t gid; 4541da177e4SLinus Torvalds 4551da177e4SLinus Torvalds if (dir->i_mode & S_ISGID) 4561da177e4SLinus Torvalds gid = dir->i_gid; 4571da177e4SLinus Torvalds else 4581da177e4SLinus Torvalds gid = current->fsgid; 4591da177e4SLinus Torvalds 4601da177e4SLinus Torvalds inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, 4611da177e4SLinus Torvalds gid, S_IFLNK|S_IRWXUGO, 0); 4621da177e4SLinus Torvalds if (inode) { 4631da177e4SLinus Torvalds int l = strlen(symname)+1; 4641da177e4SLinus Torvalds error = page_symlink(inode, symname, l); 4651da177e4SLinus Torvalds if (!error) { 4661da177e4SLinus Torvalds d_instantiate(dentry, inode); 4671da177e4SLinus Torvalds dget(dentry); 4681da177e4SLinus Torvalds } else 4691da177e4SLinus Torvalds iput(inode); 4701da177e4SLinus Torvalds } 4711da177e4SLinus Torvalds dir->i_ctime = dir->i_mtime = CURRENT_TIME; 4721da177e4SLinus Torvalds 4731da177e4SLinus Torvalds return error; 4741da177e4SLinus Torvalds } 4751da177e4SLinus Torvalds 4761da177e4SLinus Torvalds /* 4776649a386SKen Chen * mark the head page dirty 4781da177e4SLinus Torvalds */ 4791da177e4SLinus Torvalds static int hugetlbfs_set_page_dirty(struct page *page) 4801da177e4SLinus Torvalds { 481d85f3385SChristoph Lameter struct page *head = compound_head(page); 4826649a386SKen Chen 4836649a386SKen Chen SetPageDirty(head); 4841da177e4SLinus Torvalds return 0; 4851da177e4SLinus Torvalds } 4861da177e4SLinus Torvalds 487726c3342SDavid Howells static int hugetlbfs_statfs(struct dentry *dentry, struct kstatfs *buf) 4881da177e4SLinus Torvalds { 489726c3342SDavid Howells struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(dentry->d_sb); 4901da177e4SLinus Torvalds 4911da177e4SLinus Torvalds buf->f_type = HUGETLBFS_MAGIC; 4921da177e4SLinus Torvalds buf->f_bsize = HPAGE_SIZE; 4931da177e4SLinus Torvalds if (sbinfo) { 4941da177e4SLinus Torvalds spin_lock(&sbinfo->stat_lock); 49574a8a65cSDavid Gibson /* If no limits set, just report 0 for max/free/used 49674a8a65cSDavid Gibson * blocks, like simple_statfs() */ 49774a8a65cSDavid Gibson if (sbinfo->max_blocks >= 0) { 4981da177e4SLinus Torvalds buf->f_blocks = sbinfo->max_blocks; 4991da177e4SLinus Torvalds buf->f_bavail = buf->f_bfree = sbinfo->free_blocks; 5001da177e4SLinus Torvalds buf->f_files = sbinfo->max_inodes; 5011da177e4SLinus Torvalds buf->f_ffree = sbinfo->free_inodes; 50274a8a65cSDavid Gibson } 5031da177e4SLinus Torvalds spin_unlock(&sbinfo->stat_lock); 5041da177e4SLinus Torvalds } 5051da177e4SLinus Torvalds buf->f_namelen = NAME_MAX; 5061da177e4SLinus Torvalds return 0; 5071da177e4SLinus Torvalds } 5081da177e4SLinus Torvalds 5091da177e4SLinus Torvalds static void hugetlbfs_put_super(struct super_block *sb) 5101da177e4SLinus Torvalds { 5111da177e4SLinus Torvalds struct hugetlbfs_sb_info *sbi = HUGETLBFS_SB(sb); 5121da177e4SLinus Torvalds 5131da177e4SLinus Torvalds if (sbi) { 5141da177e4SLinus Torvalds sb->s_fs_info = NULL; 5151da177e4SLinus Torvalds kfree(sbi); 5161da177e4SLinus Torvalds } 5171da177e4SLinus Torvalds } 5181da177e4SLinus Torvalds 51996527980SChristoph Hellwig static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info *sbinfo) 52096527980SChristoph Hellwig { 52196527980SChristoph Hellwig if (sbinfo->free_inodes >= 0) { 52296527980SChristoph Hellwig spin_lock(&sbinfo->stat_lock); 52396527980SChristoph Hellwig if (unlikely(!sbinfo->free_inodes)) { 52496527980SChristoph Hellwig spin_unlock(&sbinfo->stat_lock); 52596527980SChristoph Hellwig return 0; 52696527980SChristoph Hellwig } 52796527980SChristoph Hellwig sbinfo->free_inodes--; 52896527980SChristoph Hellwig spin_unlock(&sbinfo->stat_lock); 52996527980SChristoph Hellwig } 53096527980SChristoph Hellwig 53196527980SChristoph Hellwig return 1; 53296527980SChristoph Hellwig } 53396527980SChristoph Hellwig 53496527980SChristoph Hellwig static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info *sbinfo) 53596527980SChristoph Hellwig { 53696527980SChristoph Hellwig if (sbinfo->free_inodes >= 0) { 53796527980SChristoph Hellwig spin_lock(&sbinfo->stat_lock); 53896527980SChristoph Hellwig sbinfo->free_inodes++; 53996527980SChristoph Hellwig spin_unlock(&sbinfo->stat_lock); 54096527980SChristoph Hellwig } 54196527980SChristoph Hellwig } 54296527980SChristoph Hellwig 54396527980SChristoph Hellwig 544e18b890bSChristoph Lameter static struct kmem_cache *hugetlbfs_inode_cachep; 5451da177e4SLinus Torvalds 5461da177e4SLinus Torvalds static struct inode *hugetlbfs_alloc_inode(struct super_block *sb) 5471da177e4SLinus Torvalds { 54896527980SChristoph Hellwig struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb); 5491da177e4SLinus Torvalds struct hugetlbfs_inode_info *p; 5501da177e4SLinus Torvalds 55196527980SChristoph Hellwig if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo))) 5521da177e4SLinus Torvalds return NULL; 553e94b1766SChristoph Lameter p = kmem_cache_alloc(hugetlbfs_inode_cachep, GFP_KERNEL); 55496527980SChristoph Hellwig if (unlikely(!p)) { 55596527980SChristoph Hellwig hugetlbfs_inc_free_inodes(sbinfo); 55696527980SChristoph Hellwig return NULL; 5571da177e4SLinus Torvalds } 55896527980SChristoph Hellwig return &p->vfs_inode; 5591da177e4SLinus Torvalds } 5601da177e4SLinus Torvalds 5611da177e4SLinus Torvalds static void hugetlbfs_destroy_inode(struct inode *inode) 5621da177e4SLinus Torvalds { 56396527980SChristoph Hellwig hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode->i_sb)); 5641da177e4SLinus Torvalds mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy); 5651da177e4SLinus Torvalds kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode)); 5661da177e4SLinus Torvalds } 5671da177e4SLinus Torvalds 568f5e54d6eSChristoph Hellwig static const struct address_space_operations hugetlbfs_aops = { 5691da177e4SLinus Torvalds .readpage = hugetlbfs_readpage, 570800d15a5SNick Piggin .write_begin = hugetlbfs_write_begin, 571800d15a5SNick Piggin .write_end = hugetlbfs_write_end, 5721da177e4SLinus Torvalds .set_page_dirty = hugetlbfs_set_page_dirty, 5731da177e4SLinus Torvalds }; 5741da177e4SLinus Torvalds 57596527980SChristoph Hellwig 576e18b890bSChristoph Lameter static void init_once(void *foo, struct kmem_cache *cachep, unsigned long flags) 57796527980SChristoph Hellwig { 57896527980SChristoph Hellwig struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo; 57996527980SChristoph Hellwig 58096527980SChristoph Hellwig inode_init_once(&ei->vfs_inode); 58196527980SChristoph Hellwig } 58296527980SChristoph Hellwig 5834b6f5d20SArjan van de Ven const struct file_operations hugetlbfs_file_operations = { 5841da177e4SLinus Torvalds .mmap = hugetlbfs_file_mmap, 5851da177e4SLinus Torvalds .fsync = simple_sync_file, 5861da177e4SLinus Torvalds .get_unmapped_area = hugetlb_get_unmapped_area, 5871da177e4SLinus Torvalds }; 5881da177e4SLinus Torvalds 58992e1d5beSArjan van de Ven static const struct inode_operations hugetlbfs_dir_inode_operations = { 5901da177e4SLinus Torvalds .create = hugetlbfs_create, 5911da177e4SLinus Torvalds .lookup = simple_lookup, 5921da177e4SLinus Torvalds .link = simple_link, 5931da177e4SLinus Torvalds .unlink = simple_unlink, 5941da177e4SLinus Torvalds .symlink = hugetlbfs_symlink, 5951da177e4SLinus Torvalds .mkdir = hugetlbfs_mkdir, 5961da177e4SLinus Torvalds .rmdir = simple_rmdir, 5971da177e4SLinus Torvalds .mknod = hugetlbfs_mknod, 5981da177e4SLinus Torvalds .rename = simple_rename, 5991da177e4SLinus Torvalds .setattr = hugetlbfs_setattr, 6001da177e4SLinus Torvalds }; 6011da177e4SLinus Torvalds 60292e1d5beSArjan van de Ven static const struct inode_operations hugetlbfs_inode_operations = { 6031da177e4SLinus Torvalds .setattr = hugetlbfs_setattr, 6041da177e4SLinus Torvalds }; 6051da177e4SLinus Torvalds 606ee9b6d61SJosef 'Jeff' Sipek static const struct super_operations hugetlbfs_ops = { 6071da177e4SLinus Torvalds .alloc_inode = hugetlbfs_alloc_inode, 6081da177e4SLinus Torvalds .destroy_inode = hugetlbfs_destroy_inode, 6091da177e4SLinus Torvalds .statfs = hugetlbfs_statfs, 610149f4211SChristoph Hellwig .delete_inode = hugetlbfs_delete_inode, 6111da177e4SLinus Torvalds .drop_inode = hugetlbfs_drop_inode, 6121da177e4SLinus Torvalds .put_super = hugetlbfs_put_super, 6131da177e4SLinus Torvalds }; 6141da177e4SLinus Torvalds 6151da177e4SLinus Torvalds static int 6161da177e4SLinus Torvalds hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) 6171da177e4SLinus Torvalds { 618e73a75faSRandy Dunlap char *p, *rest; 619e73a75faSRandy Dunlap substring_t args[MAX_OPT_ARGS]; 620e73a75faSRandy Dunlap int option; 6211da177e4SLinus Torvalds 6221da177e4SLinus Torvalds if (!options) 6231da177e4SLinus Torvalds return 0; 6241da177e4SLinus Torvalds 625e73a75faSRandy Dunlap while ((p = strsep(&options, ",")) != NULL) { 626e73a75faSRandy Dunlap int token; 627b4c07bceSLee Schermerhorn if (!*p) 628b4c07bceSLee Schermerhorn continue; 6291da177e4SLinus Torvalds 630e73a75faSRandy Dunlap token = match_token(p, tokens, args); 631e73a75faSRandy Dunlap switch (token) { 632e73a75faSRandy Dunlap case Opt_uid: 633e73a75faSRandy Dunlap if (match_int(&args[0], &option)) 634e73a75faSRandy Dunlap goto bad_val; 635e73a75faSRandy Dunlap pconfig->uid = option; 636e73a75faSRandy Dunlap break; 637e73a75faSRandy Dunlap 638e73a75faSRandy Dunlap case Opt_gid: 639e73a75faSRandy Dunlap if (match_int(&args[0], &option)) 640e73a75faSRandy Dunlap goto bad_val; 641e73a75faSRandy Dunlap pconfig->gid = option; 642e73a75faSRandy Dunlap break; 643e73a75faSRandy Dunlap 644e73a75faSRandy Dunlap case Opt_mode: 645e73a75faSRandy Dunlap if (match_octal(&args[0], &option)) 646e73a75faSRandy Dunlap goto bad_val; 647e73a75faSRandy Dunlap pconfig->mode = option & 0777U; 648e73a75faSRandy Dunlap break; 649e73a75faSRandy Dunlap 650e73a75faSRandy Dunlap case Opt_size: { 651e73a75faSRandy Dunlap unsigned long long size; 652e73a75faSRandy Dunlap /* memparse() will accept a K/M/G without a digit */ 653e73a75faSRandy Dunlap if (!isdigit(*args[0].from)) 654e73a75faSRandy Dunlap goto bad_val; 655e73a75faSRandy Dunlap size = memparse(args[0].from, &rest); 6561da177e4SLinus Torvalds if (*rest == '%') { 6571da177e4SLinus Torvalds size <<= HPAGE_SHIFT; 6581da177e4SLinus Torvalds size *= max_huge_pages; 6591da177e4SLinus Torvalds do_div(size, 100); 6601da177e4SLinus Torvalds } 6611da177e4SLinus Torvalds pconfig->nr_blocks = (size >> HPAGE_SHIFT); 662e73a75faSRandy Dunlap break; 663e73a75faSRandy Dunlap } 6641da177e4SLinus Torvalds 665e73a75faSRandy Dunlap case Opt_nr_inodes: 666e73a75faSRandy Dunlap /* memparse() will accept a K/M/G without a digit */ 667e73a75faSRandy Dunlap if (!isdigit(*args[0].from)) 668e73a75faSRandy Dunlap goto bad_val; 669e73a75faSRandy Dunlap pconfig->nr_inodes = memparse(args[0].from, &rest); 670e73a75faSRandy Dunlap break; 671e73a75faSRandy Dunlap 672e73a75faSRandy Dunlap default: 673b4c07bceSLee Schermerhorn printk(KERN_ERR "hugetlbfs: Bad mount option: \"%s\"\n", 674b4c07bceSLee Schermerhorn p); 675b4c07bceSLee Schermerhorn return -EINVAL; 676e73a75faSRandy Dunlap break; 677e73a75faSRandy Dunlap } 6781da177e4SLinus Torvalds } 6791da177e4SLinus Torvalds return 0; 680e73a75faSRandy Dunlap 681e73a75faSRandy Dunlap bad_val: 682e73a75faSRandy Dunlap printk(KERN_ERR "hugetlbfs: Bad value '%s' for mount option '%s'\n", 683e73a75faSRandy Dunlap args[0].from, p); 684e73a75faSRandy Dunlap return 1; 6851da177e4SLinus Torvalds } 6861da177e4SLinus Torvalds 6871da177e4SLinus Torvalds static int 6881da177e4SLinus Torvalds hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) 6891da177e4SLinus Torvalds { 6901da177e4SLinus Torvalds struct inode * inode; 6911da177e4SLinus Torvalds struct dentry * root; 6921da177e4SLinus Torvalds int ret; 6931da177e4SLinus Torvalds struct hugetlbfs_config config; 6941da177e4SLinus Torvalds struct hugetlbfs_sb_info *sbinfo; 6951da177e4SLinus Torvalds 6961da177e4SLinus Torvalds config.nr_blocks = -1; /* No limit on size by default */ 6971da177e4SLinus Torvalds config.nr_inodes = -1; /* No limit on number of inodes by default */ 6981da177e4SLinus Torvalds config.uid = current->fsuid; 6991da177e4SLinus Torvalds config.gid = current->fsgid; 7001da177e4SLinus Torvalds config.mode = 0755; 7011da177e4SLinus Torvalds ret = hugetlbfs_parse_options(data, &config); 7021da177e4SLinus Torvalds if (ret) 7031da177e4SLinus Torvalds return ret; 7041da177e4SLinus Torvalds 7051da177e4SLinus Torvalds sbinfo = kmalloc(sizeof(struct hugetlbfs_sb_info), GFP_KERNEL); 7061da177e4SLinus Torvalds if (!sbinfo) 7071da177e4SLinus Torvalds return -ENOMEM; 7081da177e4SLinus Torvalds sb->s_fs_info = sbinfo; 7091da177e4SLinus Torvalds spin_lock_init(&sbinfo->stat_lock); 7101da177e4SLinus Torvalds sbinfo->max_blocks = config.nr_blocks; 7111da177e4SLinus Torvalds sbinfo->free_blocks = config.nr_blocks; 7121da177e4SLinus Torvalds sbinfo->max_inodes = config.nr_inodes; 7131da177e4SLinus Torvalds sbinfo->free_inodes = config.nr_inodes; 7141da177e4SLinus Torvalds sb->s_maxbytes = MAX_LFS_FILESIZE; 7151da177e4SLinus Torvalds sb->s_blocksize = HPAGE_SIZE; 7161da177e4SLinus Torvalds sb->s_blocksize_bits = HPAGE_SHIFT; 7171da177e4SLinus Torvalds sb->s_magic = HUGETLBFS_MAGIC; 7181da177e4SLinus Torvalds sb->s_op = &hugetlbfs_ops; 7191da177e4SLinus Torvalds sb->s_time_gran = 1; 7201da177e4SLinus Torvalds inode = hugetlbfs_get_inode(sb, config.uid, config.gid, 7211da177e4SLinus Torvalds S_IFDIR | config.mode, 0); 7221da177e4SLinus Torvalds if (!inode) 7231da177e4SLinus Torvalds goto out_free; 7241da177e4SLinus Torvalds 7251da177e4SLinus Torvalds root = d_alloc_root(inode); 7261da177e4SLinus Torvalds if (!root) { 7271da177e4SLinus Torvalds iput(inode); 7281da177e4SLinus Torvalds goto out_free; 7291da177e4SLinus Torvalds } 7301da177e4SLinus Torvalds sb->s_root = root; 7311da177e4SLinus Torvalds return 0; 7321da177e4SLinus Torvalds out_free: 7331da177e4SLinus Torvalds kfree(sbinfo); 7341da177e4SLinus Torvalds return -ENOMEM; 7351da177e4SLinus Torvalds } 7361da177e4SLinus Torvalds 7371da177e4SLinus Torvalds int hugetlb_get_quota(struct address_space *mapping) 7381da177e4SLinus Torvalds { 7391da177e4SLinus Torvalds int ret = 0; 7401da177e4SLinus Torvalds struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); 7411da177e4SLinus Torvalds 7421da177e4SLinus Torvalds if (sbinfo->free_blocks > -1) { 7431da177e4SLinus Torvalds spin_lock(&sbinfo->stat_lock); 7441da177e4SLinus Torvalds if (sbinfo->free_blocks > 0) 7451da177e4SLinus Torvalds sbinfo->free_blocks--; 7461da177e4SLinus Torvalds else 7471da177e4SLinus Torvalds ret = -ENOMEM; 7481da177e4SLinus Torvalds spin_unlock(&sbinfo->stat_lock); 7491da177e4SLinus Torvalds } 7501da177e4SLinus Torvalds 7511da177e4SLinus Torvalds return ret; 7521da177e4SLinus Torvalds } 7531da177e4SLinus Torvalds 7541da177e4SLinus Torvalds void hugetlb_put_quota(struct address_space *mapping) 7551da177e4SLinus Torvalds { 7561da177e4SLinus Torvalds struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); 7571da177e4SLinus Torvalds 7581da177e4SLinus Torvalds if (sbinfo->free_blocks > -1) { 7591da177e4SLinus Torvalds spin_lock(&sbinfo->stat_lock); 7601da177e4SLinus Torvalds sbinfo->free_blocks++; 7611da177e4SLinus Torvalds spin_unlock(&sbinfo->stat_lock); 7621da177e4SLinus Torvalds } 7631da177e4SLinus Torvalds } 7641da177e4SLinus Torvalds 765454e2398SDavid Howells static int hugetlbfs_get_sb(struct file_system_type *fs_type, 766454e2398SDavid Howells int flags, const char *dev_name, void *data, struct vfsmount *mnt) 7671da177e4SLinus Torvalds { 768454e2398SDavid Howells return get_sb_nodev(fs_type, flags, data, hugetlbfs_fill_super, mnt); 7691da177e4SLinus Torvalds } 7701da177e4SLinus Torvalds 7711da177e4SLinus Torvalds static struct file_system_type hugetlbfs_fs_type = { 7721da177e4SLinus Torvalds .name = "hugetlbfs", 7731da177e4SLinus Torvalds .get_sb = hugetlbfs_get_sb, 7741da177e4SLinus Torvalds .kill_sb = kill_litter_super, 7751da177e4SLinus Torvalds }; 7761da177e4SLinus Torvalds 7771da177e4SLinus Torvalds static struct vfsmount *hugetlbfs_vfsmount; 7781da177e4SLinus Torvalds 7791da177e4SLinus Torvalds static int can_do_hugetlb_shm(void) 7801da177e4SLinus Torvalds { 7811da177e4SLinus Torvalds return likely(capable(CAP_IPC_LOCK) || 7821da177e4SLinus Torvalds in_group_p(sysctl_hugetlb_shm_group) || 7831da177e4SLinus Torvalds can_do_mlock()); 7841da177e4SLinus Torvalds } 7851da177e4SLinus Torvalds 7869d66586fSEric W. Biederman struct file *hugetlb_file_setup(const char *name, size_t size) 7871da177e4SLinus Torvalds { 7881da177e4SLinus Torvalds int error = -ENOMEM; 7891da177e4SLinus Torvalds struct file *file; 7901da177e4SLinus Torvalds struct inode *inode; 7911da177e4SLinus Torvalds struct dentry *dentry, *root; 7921da177e4SLinus Torvalds struct qstr quick_string; 7931da177e4SLinus Torvalds 7945bc98594SAkinobu Mita if (!hugetlbfs_vfsmount) 7955bc98594SAkinobu Mita return ERR_PTR(-ENOENT); 7965bc98594SAkinobu Mita 7971da177e4SLinus Torvalds if (!can_do_hugetlb_shm()) 7981da177e4SLinus Torvalds return ERR_PTR(-EPERM); 7991da177e4SLinus Torvalds 8001da177e4SLinus Torvalds if (!user_shm_lock(size, current->user)) 8011da177e4SLinus Torvalds return ERR_PTR(-ENOMEM); 8021da177e4SLinus Torvalds 8031da177e4SLinus Torvalds root = hugetlbfs_vfsmount->mnt_root; 8049d66586fSEric W. Biederman quick_string.name = name; 8051da177e4SLinus Torvalds quick_string.len = strlen(quick_string.name); 8061da177e4SLinus Torvalds quick_string.hash = 0; 8071da177e4SLinus Torvalds dentry = d_alloc(root, &quick_string); 8081da177e4SLinus Torvalds if (!dentry) 8091da177e4SLinus Torvalds goto out_shm_unlock; 8101da177e4SLinus Torvalds 8111da177e4SLinus Torvalds error = -ENFILE; 8121da177e4SLinus Torvalds file = get_empty_filp(); 8131da177e4SLinus Torvalds if (!file) 8141da177e4SLinus Torvalds goto out_dentry; 8151da177e4SLinus Torvalds 8161da177e4SLinus Torvalds error = -ENOSPC; 8171da177e4SLinus Torvalds inode = hugetlbfs_get_inode(root->d_sb, current->fsuid, 8181da177e4SLinus Torvalds current->fsgid, S_IFREG | S_IRWXUGO, 0); 8191da177e4SLinus Torvalds if (!inode) 8201da177e4SLinus Torvalds goto out_file; 8211da177e4SLinus Torvalds 822b45b5bd6SDavid Gibson error = -ENOMEM; 823a43a8c39SChen, Kenneth W if (hugetlb_reserve_pages(inode, 0, size >> HPAGE_SHIFT)) 824b45b5bd6SDavid Gibson goto out_inode; 825b45b5bd6SDavid Gibson 8261da177e4SLinus Torvalds d_instantiate(dentry, inode); 8271da177e4SLinus Torvalds inode->i_size = size; 8281da177e4SLinus Torvalds inode->i_nlink = 0; 829b39424e2SJosef Sipek file->f_path.mnt = mntget(hugetlbfs_vfsmount); 830b39424e2SJosef Sipek file->f_path.dentry = dentry; 8311da177e4SLinus Torvalds file->f_mapping = inode->i_mapping; 8321da177e4SLinus Torvalds file->f_op = &hugetlbfs_file_operations; 8331da177e4SLinus Torvalds file->f_mode = FMODE_WRITE | FMODE_READ; 8341da177e4SLinus Torvalds return file; 8351da177e4SLinus Torvalds 836b45b5bd6SDavid Gibson out_inode: 837b45b5bd6SDavid Gibson iput(inode); 8381da177e4SLinus Torvalds out_file: 8391da177e4SLinus Torvalds put_filp(file); 8401da177e4SLinus Torvalds out_dentry: 8411da177e4SLinus Torvalds dput(dentry); 8421da177e4SLinus Torvalds out_shm_unlock: 8431da177e4SLinus Torvalds user_shm_unlock(size, current->user); 8441da177e4SLinus Torvalds return ERR_PTR(error); 8451da177e4SLinus Torvalds } 8461da177e4SLinus Torvalds 8471da177e4SLinus Torvalds static int __init init_hugetlbfs_fs(void) 8481da177e4SLinus Torvalds { 8491da177e4SLinus Torvalds int error; 8501da177e4SLinus Torvalds struct vfsmount *vfsmount; 8511da177e4SLinus Torvalds 8521da177e4SLinus Torvalds hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache", 8531da177e4SLinus Torvalds sizeof(struct hugetlbfs_inode_info), 85420c2df83SPaul Mundt 0, 0, init_once); 8551da177e4SLinus Torvalds if (hugetlbfs_inode_cachep == NULL) 8561da177e4SLinus Torvalds return -ENOMEM; 8571da177e4SLinus Torvalds 8581da177e4SLinus Torvalds error = register_filesystem(&hugetlbfs_fs_type); 8591da177e4SLinus Torvalds if (error) 8601da177e4SLinus Torvalds goto out; 8611da177e4SLinus Torvalds 8621da177e4SLinus Torvalds vfsmount = kern_mount(&hugetlbfs_fs_type); 8631da177e4SLinus Torvalds 8641da177e4SLinus Torvalds if (!IS_ERR(vfsmount)) { 8651da177e4SLinus Torvalds hugetlbfs_vfsmount = vfsmount; 8661da177e4SLinus Torvalds return 0; 8671da177e4SLinus Torvalds } 8681da177e4SLinus Torvalds 8691da177e4SLinus Torvalds error = PTR_ERR(vfsmount); 8701da177e4SLinus Torvalds 8711da177e4SLinus Torvalds out: 8721da177e4SLinus Torvalds if (error) 8731da177e4SLinus Torvalds kmem_cache_destroy(hugetlbfs_inode_cachep); 8741da177e4SLinus Torvalds return error; 8751da177e4SLinus Torvalds } 8761da177e4SLinus Torvalds 8771da177e4SLinus Torvalds static void __exit exit_hugetlbfs_fs(void) 8781da177e4SLinus Torvalds { 8791da177e4SLinus Torvalds kmem_cache_destroy(hugetlbfs_inode_cachep); 8801da177e4SLinus Torvalds unregister_filesystem(&hugetlbfs_fs_type); 8811da177e4SLinus Torvalds } 8821da177e4SLinus Torvalds 8831da177e4SLinus Torvalds module_init(init_hugetlbfs_fs) 8841da177e4SLinus Torvalds module_exit(exit_hugetlbfs_fs) 8851da177e4SLinus Torvalds 8861da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 887