11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * hugetlbpage-backed filesystem. Based on ramfs. 31da177e4SLinus Torvalds * 46d49e352SNadia Yvette Chambers * Nadia Yvette Chambers, 2002 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * Copyright (C) 2002 Linus Torvalds. 71da177e4SLinus Torvalds */ 81da177e4SLinus Torvalds 99b857d26SAndrew Morton #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 109b857d26SAndrew Morton 111da177e4SLinus Torvalds #include <linux/module.h> 121da177e4SLinus Torvalds #include <linux/thread_info.h> 131da177e4SLinus Torvalds #include <asm/current.h> 141da177e4SLinus Torvalds #include <linux/sched.h> /* remove ASAP */ 151da177e4SLinus Torvalds #include <linux/fs.h> 161da177e4SLinus Torvalds #include <linux/mount.h> 171da177e4SLinus Torvalds #include <linux/file.h> 18e73a75faSRandy Dunlap #include <linux/kernel.h> 191da177e4SLinus Torvalds #include <linux/writeback.h> 201da177e4SLinus Torvalds #include <linux/pagemap.h> 211da177e4SLinus Torvalds #include <linux/highmem.h> 221da177e4SLinus Torvalds #include <linux/init.h> 231da177e4SLinus Torvalds #include <linux/string.h> 2416f7e0feSRandy Dunlap #include <linux/capability.h> 25e73a75faSRandy Dunlap #include <linux/ctype.h> 261da177e4SLinus Torvalds #include <linux/backing-dev.h> 271da177e4SLinus Torvalds #include <linux/hugetlb.h> 281da177e4SLinus Torvalds #include <linux/pagevec.h> 29e73a75faSRandy Dunlap #include <linux/parser.h> 30036e0856SBenjamin Herrenschmidt #include <linux/mman.h> 311da177e4SLinus Torvalds #include <linux/slab.h> 321da177e4SLinus Torvalds #include <linux/dnotify.h> 331da177e4SLinus Torvalds #include <linux/statfs.h> 341da177e4SLinus Torvalds #include <linux/security.h> 351fd7317dSNick Black #include <linux/magic.h> 36290408d4SNaoya Horiguchi #include <linux/migrate.h> 3734d0640eSAl Viro #include <linux/uio.h> 381da177e4SLinus Torvalds 391da177e4SLinus Torvalds #include <asm/uaccess.h> 401da177e4SLinus Torvalds 41ee9b6d61SJosef 'Jeff' Sipek static const struct super_operations hugetlbfs_ops; 42f5e54d6eSChristoph Hellwig static const struct address_space_operations hugetlbfs_aops; 434b6f5d20SArjan van de Ven const struct file_operations hugetlbfs_file_operations; 4492e1d5beSArjan van de Ven static const struct inode_operations hugetlbfs_dir_inode_operations; 4592e1d5beSArjan van de Ven static const struct inode_operations hugetlbfs_inode_operations; 461da177e4SLinus Torvalds 47a1d776eeSDavid Gibson struct hugetlbfs_config { 48a0eb3a05SEric W. Biederman kuid_t uid; 49a0eb3a05SEric W. Biederman kgid_t gid; 50a1d776eeSDavid Gibson umode_t mode; 517ca02d0aSMike Kravetz long max_hpages; 52a1d776eeSDavid Gibson long nr_inodes; 53a1d776eeSDavid Gibson struct hstate *hstate; 547ca02d0aSMike Kravetz long min_hpages; 55a1d776eeSDavid Gibson }; 56a1d776eeSDavid Gibson 57a1d776eeSDavid Gibson struct hugetlbfs_inode_info { 58a1d776eeSDavid Gibson struct shared_policy policy; 59a1d776eeSDavid Gibson struct inode vfs_inode; 60a1d776eeSDavid Gibson }; 61a1d776eeSDavid Gibson 62a1d776eeSDavid Gibson static inline struct hugetlbfs_inode_info *HUGETLBFS_I(struct inode *inode) 63a1d776eeSDavid Gibson { 64a1d776eeSDavid Gibson return container_of(inode, struct hugetlbfs_inode_info, vfs_inode); 65a1d776eeSDavid Gibson } 66a1d776eeSDavid Gibson 671da177e4SLinus Torvalds int sysctl_hugetlb_shm_group; 681da177e4SLinus Torvalds 69e73a75faSRandy Dunlap enum { 70e73a75faSRandy Dunlap Opt_size, Opt_nr_inodes, 71e73a75faSRandy Dunlap Opt_mode, Opt_uid, Opt_gid, 727ca02d0aSMike Kravetz Opt_pagesize, Opt_min_size, 73e73a75faSRandy Dunlap Opt_err, 74e73a75faSRandy Dunlap }; 75e73a75faSRandy Dunlap 76a447c093SSteven Whitehouse static const match_table_t tokens = { 77e73a75faSRandy Dunlap {Opt_size, "size=%s"}, 78e73a75faSRandy Dunlap {Opt_nr_inodes, "nr_inodes=%s"}, 79e73a75faSRandy Dunlap {Opt_mode, "mode=%o"}, 80e73a75faSRandy Dunlap {Opt_uid, "uid=%u"}, 81e73a75faSRandy Dunlap {Opt_gid, "gid=%u"}, 82a137e1ccSAndi Kleen {Opt_pagesize, "pagesize=%s"}, 837ca02d0aSMike Kravetz {Opt_min_size, "min_size=%s"}, 84e73a75faSRandy Dunlap {Opt_err, NULL}, 85e73a75faSRandy Dunlap }; 86e73a75faSRandy Dunlap 872e9b367cSAdam Litke static void huge_pagevec_release(struct pagevec *pvec) 882e9b367cSAdam Litke { 892e9b367cSAdam Litke int i; 902e9b367cSAdam Litke 912e9b367cSAdam Litke for (i = 0; i < pagevec_count(pvec); ++i) 922e9b367cSAdam Litke put_page(pvec->pages[i]); 932e9b367cSAdam Litke 942e9b367cSAdam Litke pagevec_reinit(pvec); 952e9b367cSAdam Litke } 962e9b367cSAdam Litke 971da177e4SLinus Torvalds static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) 981da177e4SLinus Torvalds { 99496ad9aaSAl Viro struct inode *inode = file_inode(file); 1001da177e4SLinus Torvalds loff_t len, vma_len; 1011da177e4SLinus Torvalds int ret; 102a5516438SAndi Kleen struct hstate *h = hstate_file(file); 1031da177e4SLinus Torvalds 10468589bc3SHugh Dickins /* 105dec4ad86SDavid Gibson * vma address alignment (but not the pgoff alignment) has 106dec4ad86SDavid Gibson * already been checked by prepare_hugepage_range. If you add 107dec4ad86SDavid Gibson * any error returns here, do so after setting VM_HUGETLB, so 108dec4ad86SDavid Gibson * is_vm_hugetlb_page tests below unmap_region go the right 109dec4ad86SDavid Gibson * way when do_mmap_pgoff unwinds (may be important on powerpc 110dec4ad86SDavid Gibson * and ia64). 11168589bc3SHugh Dickins */ 112a2fce914SNaoya Horiguchi vma->vm_flags |= VM_HUGETLB | VM_DONTEXPAND; 11368589bc3SHugh Dickins vma->vm_ops = &hugetlb_vm_ops; 1141da177e4SLinus Torvalds 1152b37c35eSBecky Bruce if (vma->vm_pgoff & (~huge_page_mask(h) >> PAGE_SHIFT)) 116dec4ad86SDavid Gibson return -EINVAL; 117dec4ad86SDavid Gibson 1181da177e4SLinus Torvalds vma_len = (loff_t)(vma->vm_end - vma->vm_start); 1191da177e4SLinus Torvalds 1201b1dcc1bSJes Sorensen mutex_lock(&inode->i_mutex); 1211da177e4SLinus Torvalds file_accessed(file); 1221da177e4SLinus Torvalds 1231da177e4SLinus Torvalds ret = -ENOMEM; 1241da177e4SLinus Torvalds len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); 1251da177e4SLinus Torvalds 126a1e78772SMel Gorman if (hugetlb_reserve_pages(inode, 127a5516438SAndi Kleen vma->vm_pgoff >> huge_page_order(h), 1285a6fe125SMel Gorman len >> huge_page_shift(h), vma, 1295a6fe125SMel Gorman vma->vm_flags)) 130b45b5bd6SDavid Gibson goto out; 131b45b5bd6SDavid Gibson 1324c887265SAdam Litke ret = 0; 133b6174df5SZhang, Yanmin if (vma->vm_flags & VM_WRITE && inode->i_size < len) 1341da177e4SLinus Torvalds inode->i_size = len; 1351da177e4SLinus Torvalds out: 1361b1dcc1bSJes Sorensen mutex_unlock(&inode->i_mutex); 1371da177e4SLinus Torvalds 1381da177e4SLinus Torvalds return ret; 1391da177e4SLinus Torvalds } 1401da177e4SLinus Torvalds 1411da177e4SLinus Torvalds /* 142508034a3SHugh Dickins * Called under down_write(mmap_sem). 1431da177e4SLinus Torvalds */ 1441da177e4SLinus Torvalds 145d2ba27e8SAdrian Bunk #ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA 1461da177e4SLinus Torvalds static unsigned long 1471da177e4SLinus Torvalds hugetlb_get_unmapped_area(struct file *file, unsigned long addr, 1481da177e4SLinus Torvalds unsigned long len, unsigned long pgoff, unsigned long flags) 1491da177e4SLinus Torvalds { 1501da177e4SLinus Torvalds struct mm_struct *mm = current->mm; 1511da177e4SLinus Torvalds struct vm_area_struct *vma; 152a5516438SAndi Kleen struct hstate *h = hstate_file(file); 15308659355SMichel Lespinasse struct vm_unmapped_area_info info; 1541da177e4SLinus Torvalds 155a5516438SAndi Kleen if (len & ~huge_page_mask(h)) 1561da177e4SLinus Torvalds return -EINVAL; 1571da177e4SLinus Torvalds if (len > TASK_SIZE) 1581da177e4SLinus Torvalds return -ENOMEM; 1591da177e4SLinus Torvalds 160036e0856SBenjamin Herrenschmidt if (flags & MAP_FIXED) { 161a5516438SAndi Kleen if (prepare_hugepage_range(file, addr, len)) 162036e0856SBenjamin Herrenschmidt return -EINVAL; 163036e0856SBenjamin Herrenschmidt return addr; 164036e0856SBenjamin Herrenschmidt } 165036e0856SBenjamin Herrenschmidt 1661da177e4SLinus Torvalds if (addr) { 167a5516438SAndi Kleen addr = ALIGN(addr, huge_page_size(h)); 1681da177e4SLinus Torvalds vma = find_vma(mm, addr); 1691da177e4SLinus Torvalds if (TASK_SIZE - len >= addr && 1701da177e4SLinus Torvalds (!vma || addr + len <= vma->vm_start)) 1711da177e4SLinus Torvalds return addr; 1721da177e4SLinus Torvalds } 1731da177e4SLinus Torvalds 17408659355SMichel Lespinasse info.flags = 0; 17508659355SMichel Lespinasse info.length = len; 17608659355SMichel Lespinasse info.low_limit = TASK_UNMAPPED_BASE; 17708659355SMichel Lespinasse info.high_limit = TASK_SIZE; 17808659355SMichel Lespinasse info.align_mask = PAGE_MASK & ~huge_page_mask(h); 17908659355SMichel Lespinasse info.align_offset = 0; 18008659355SMichel Lespinasse return vm_unmapped_area(&info); 1811da177e4SLinus Torvalds } 1821da177e4SLinus Torvalds #endif 1831da177e4SLinus Torvalds 18434d0640eSAl Viro static size_t 185e63e1e5aSBadari Pulavarty hugetlbfs_read_actor(struct page *page, unsigned long offset, 18634d0640eSAl Viro struct iov_iter *to, unsigned long size) 187e63e1e5aSBadari Pulavarty { 18834d0640eSAl Viro size_t copied = 0; 189e63e1e5aSBadari Pulavarty int i, chunksize; 190e63e1e5aSBadari Pulavarty 191e63e1e5aSBadari Pulavarty /* Find which 4k chunk and offset with in that chunk */ 192e63e1e5aSBadari Pulavarty i = offset >> PAGE_CACHE_SHIFT; 193e63e1e5aSBadari Pulavarty offset = offset & ~PAGE_CACHE_MASK; 194e63e1e5aSBadari Pulavarty 195e63e1e5aSBadari Pulavarty while (size) { 19634d0640eSAl Viro size_t n; 197e63e1e5aSBadari Pulavarty chunksize = PAGE_CACHE_SIZE; 198e63e1e5aSBadari Pulavarty if (offset) 199e63e1e5aSBadari Pulavarty chunksize -= offset; 200e63e1e5aSBadari Pulavarty if (chunksize > size) 201e63e1e5aSBadari Pulavarty chunksize = size; 20234d0640eSAl Viro n = copy_page_to_iter(&page[i], offset, chunksize, to); 20334d0640eSAl Viro copied += n; 20434d0640eSAl Viro if (n != chunksize) 20534d0640eSAl Viro return copied; 206e63e1e5aSBadari Pulavarty offset = 0; 207e63e1e5aSBadari Pulavarty size -= chunksize; 208e63e1e5aSBadari Pulavarty i++; 209e63e1e5aSBadari Pulavarty } 21034d0640eSAl Viro return copied; 211e63e1e5aSBadari Pulavarty } 212e63e1e5aSBadari Pulavarty 213e63e1e5aSBadari Pulavarty /* 214e63e1e5aSBadari Pulavarty * Support for read() - Find the page attached to f_mapping and copy out the 215e63e1e5aSBadari Pulavarty * data. Its *very* similar to do_generic_mapping_read(), we can't use that 216e63e1e5aSBadari Pulavarty * since it has PAGE_CACHE_SIZE assumptions. 217e63e1e5aSBadari Pulavarty */ 21834d0640eSAl Viro static ssize_t hugetlbfs_read_iter(struct kiocb *iocb, struct iov_iter *to) 219e63e1e5aSBadari Pulavarty { 22034d0640eSAl Viro struct file *file = iocb->ki_filp; 22134d0640eSAl Viro struct hstate *h = hstate_file(file); 22234d0640eSAl Viro struct address_space *mapping = file->f_mapping; 223e63e1e5aSBadari Pulavarty struct inode *inode = mapping->host; 22434d0640eSAl Viro unsigned long index = iocb->ki_pos >> huge_page_shift(h); 22534d0640eSAl Viro unsigned long offset = iocb->ki_pos & ~huge_page_mask(h); 226e63e1e5aSBadari Pulavarty unsigned long end_index; 227e63e1e5aSBadari Pulavarty loff_t isize; 228e63e1e5aSBadari Pulavarty ssize_t retval = 0; 229e63e1e5aSBadari Pulavarty 23034d0640eSAl Viro while (iov_iter_count(to)) { 231e63e1e5aSBadari Pulavarty struct page *page; 23234d0640eSAl Viro size_t nr, copied; 233e63e1e5aSBadari Pulavarty 234e63e1e5aSBadari Pulavarty /* nr is the maximum number of bytes to copy from this page */ 235a5516438SAndi Kleen nr = huge_page_size(h); 236a05b0855SAneesh Kumar K.V isize = i_size_read(inode); 237a05b0855SAneesh Kumar K.V if (!isize) 23834d0640eSAl Viro break; 239a05b0855SAneesh Kumar K.V end_index = (isize - 1) >> huge_page_shift(h); 240e63e1e5aSBadari Pulavarty if (index > end_index) 24134d0640eSAl Viro break; 24234d0640eSAl Viro if (index == end_index) { 243a5516438SAndi Kleen nr = ((isize - 1) & ~huge_page_mask(h)) + 1; 244a05b0855SAneesh Kumar K.V if (nr <= offset) 24534d0640eSAl Viro break; 246e63e1e5aSBadari Pulavarty } 247e63e1e5aSBadari Pulavarty nr = nr - offset; 248e63e1e5aSBadari Pulavarty 249e63e1e5aSBadari Pulavarty /* Find the page */ 250a05b0855SAneesh Kumar K.V page = find_lock_page(mapping, index); 251e63e1e5aSBadari Pulavarty if (unlikely(page == NULL)) { 252e63e1e5aSBadari Pulavarty /* 253e63e1e5aSBadari Pulavarty * We have a HOLE, zero out the user-buffer for the 254e63e1e5aSBadari Pulavarty * length of the hole or request. 255e63e1e5aSBadari Pulavarty */ 25634d0640eSAl Viro copied = iov_iter_zero(nr, to); 257e63e1e5aSBadari Pulavarty } else { 258a05b0855SAneesh Kumar K.V unlock_page(page); 259a05b0855SAneesh Kumar K.V 260e63e1e5aSBadari Pulavarty /* 261e63e1e5aSBadari Pulavarty * We have the page, copy it to user space buffer. 262e63e1e5aSBadari Pulavarty */ 26334d0640eSAl Viro copied = hugetlbfs_read_actor(page, offset, to, nr); 264a05b0855SAneesh Kumar K.V page_cache_release(page); 265e63e1e5aSBadari Pulavarty } 26634d0640eSAl Viro offset += copied; 26734d0640eSAl Viro retval += copied; 26834d0640eSAl Viro if (copied != nr && iov_iter_count(to)) { 26934d0640eSAl Viro if (!retval) 27034d0640eSAl Viro retval = -EFAULT; 271e63e1e5aSBadari Pulavarty break; 272e63e1e5aSBadari Pulavarty } 27334d0640eSAl Viro index += offset >> huge_page_shift(h); 27434d0640eSAl Viro offset &= ~huge_page_mask(h); 27534d0640eSAl Viro } 27634d0640eSAl Viro iocb->ki_pos = ((loff_t)index << huge_page_shift(h)) + offset; 277e63e1e5aSBadari Pulavarty return retval; 278e63e1e5aSBadari Pulavarty } 279e63e1e5aSBadari Pulavarty 280800d15a5SNick Piggin static int hugetlbfs_write_begin(struct file *file, 281800d15a5SNick Piggin struct address_space *mapping, 282800d15a5SNick Piggin loff_t pos, unsigned len, unsigned flags, 283800d15a5SNick Piggin struct page **pagep, void **fsdata) 2841da177e4SLinus Torvalds { 2851da177e4SLinus Torvalds return -EINVAL; 2861da177e4SLinus Torvalds } 2871da177e4SLinus Torvalds 288800d15a5SNick Piggin static int hugetlbfs_write_end(struct file *file, struct address_space *mapping, 289800d15a5SNick Piggin loff_t pos, unsigned len, unsigned copied, 290800d15a5SNick Piggin struct page *page, void *fsdata) 2911da177e4SLinus Torvalds { 292800d15a5SNick Piggin BUG(); 2931da177e4SLinus Torvalds return -EINVAL; 2941da177e4SLinus Torvalds } 2951da177e4SLinus Torvalds 2961da177e4SLinus Torvalds static void truncate_huge_page(struct page *page) 2971da177e4SLinus Torvalds { 298b9ea2515SKonstantin Khlebnikov ClearPageDirty(page); 2991da177e4SLinus Torvalds ClearPageUptodate(page); 300bd65cb86SMinchan Kim delete_from_page_cache(page); 3011da177e4SLinus Torvalds } 3021da177e4SLinus Torvalds 303b45b5bd6SDavid Gibson static void truncate_hugepages(struct inode *inode, loff_t lstart) 3041da177e4SLinus Torvalds { 305a5516438SAndi Kleen struct hstate *h = hstate_inode(inode); 306b45b5bd6SDavid Gibson struct address_space *mapping = &inode->i_data; 307a5516438SAndi Kleen const pgoff_t start = lstart >> huge_page_shift(h); 3081da177e4SLinus Torvalds struct pagevec pvec; 3091da177e4SLinus Torvalds pgoff_t next; 310a43a8c39SChen, Kenneth W int i, freed = 0; 3111da177e4SLinus Torvalds 3121da177e4SLinus Torvalds pagevec_init(&pvec, 0); 3131da177e4SLinus Torvalds next = start; 3141da177e4SLinus Torvalds while (1) { 3151da177e4SLinus Torvalds if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { 3161da177e4SLinus Torvalds if (next == start) 3171da177e4SLinus Torvalds break; 3181da177e4SLinus Torvalds next = start; 3191da177e4SLinus Torvalds continue; 3201da177e4SLinus Torvalds } 3211da177e4SLinus Torvalds 3221da177e4SLinus Torvalds for (i = 0; i < pagevec_count(&pvec); ++i) { 3231da177e4SLinus Torvalds struct page *page = pvec.pages[i]; 3241da177e4SLinus Torvalds 3251da177e4SLinus Torvalds lock_page(page); 3261da177e4SLinus Torvalds if (page->index > next) 3271da177e4SLinus Torvalds next = page->index; 3281da177e4SLinus Torvalds ++next; 3291da177e4SLinus Torvalds truncate_huge_page(page); 3301da177e4SLinus Torvalds unlock_page(page); 331a43a8c39SChen, Kenneth W freed++; 3321da177e4SLinus Torvalds } 3331da177e4SLinus Torvalds huge_pagevec_release(&pvec); 3341da177e4SLinus Torvalds } 3351da177e4SLinus Torvalds BUG_ON(!lstart && mapping->nrpages); 336a43a8c39SChen, Kenneth W hugetlb_unreserve_pages(inode, start, freed); 3371da177e4SLinus Torvalds } 3381da177e4SLinus Torvalds 3392bbbda30SAl Viro static void hugetlbfs_evict_inode(struct inode *inode) 3401da177e4SLinus Torvalds { 3419119a41eSJoonsoo Kim struct resv_map *resv_map; 3429119a41eSJoonsoo Kim 343b45b5bd6SDavid Gibson truncate_hugepages(inode, 0); 3449119a41eSJoonsoo Kim resv_map = (struct resv_map *)inode->i_mapping->private_data; 3459119a41eSJoonsoo Kim /* root inode doesn't have the resv_map, so we should check it */ 3469119a41eSJoonsoo Kim if (resv_map) 3479119a41eSJoonsoo Kim resv_map_release(&resv_map->refs); 348dbd5768fSJan Kara clear_inode(inode); 349149f4211SChristoph Hellwig } 350149f4211SChristoph Hellwig 3511da177e4SLinus Torvalds static inline void 3521bfad99aSMike Kravetz hugetlb_vmdelete_list(struct rb_root *root, pgoff_t start, pgoff_t end) 3531da177e4SLinus Torvalds { 3541da177e4SLinus Torvalds struct vm_area_struct *vma; 3551da177e4SLinus Torvalds 3561bfad99aSMike Kravetz /* 3571bfad99aSMike Kravetz * end == 0 indicates that the entire range after 3581bfad99aSMike Kravetz * start should be unmapped. 3591bfad99aSMike Kravetz */ 3601bfad99aSMike Kravetz vma_interval_tree_foreach(vma, root, start, end ? end : ULONG_MAX) { 3611da177e4SLinus Torvalds unsigned long v_offset; 3621da177e4SLinus Torvalds 3631da177e4SLinus Torvalds /* 364856fc295SHugh Dickins * Can the expression below overflow on 32-bit arches? 3656b2dbba8SMichel Lespinasse * No, because the interval tree returns us only those vmas 366856fc295SHugh Dickins * which overlap the truncated area starting at pgoff, 367856fc295SHugh Dickins * and no vma on a 32-bit arch can span beyond the 4GB. 3681da177e4SLinus Torvalds */ 3691bfad99aSMike Kravetz if (vma->vm_pgoff < start) 3701bfad99aSMike Kravetz v_offset = (start - vma->vm_pgoff) << PAGE_SHIFT; 371856fc295SHugh Dickins else 3721da177e4SLinus Torvalds v_offset = 0; 3731da177e4SLinus Torvalds 3741bfad99aSMike Kravetz if (end) { 3751bfad99aSMike Kravetz end = ((end - start) << PAGE_SHIFT) + 3761bfad99aSMike Kravetz vma->vm_start + v_offset; 3771bfad99aSMike Kravetz if (end > vma->vm_end) 3781bfad99aSMike Kravetz end = vma->vm_end; 3791bfad99aSMike Kravetz } else 3801bfad99aSMike Kravetz end = vma->vm_end; 3811bfad99aSMike Kravetz 3821bfad99aSMike Kravetz unmap_hugepage_range(vma, vma->vm_start + v_offset, end, NULL); 3831da177e4SLinus Torvalds } 3841da177e4SLinus Torvalds } 3851da177e4SLinus Torvalds 3861da177e4SLinus Torvalds static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) 3871da177e4SLinus Torvalds { 388856fc295SHugh Dickins pgoff_t pgoff; 3891da177e4SLinus Torvalds struct address_space *mapping = inode->i_mapping; 390a5516438SAndi Kleen struct hstate *h = hstate_inode(inode); 3911da177e4SLinus Torvalds 392a5516438SAndi Kleen BUG_ON(offset & ~huge_page_mask(h)); 393856fc295SHugh Dickins pgoff = offset >> PAGE_SHIFT; 3941da177e4SLinus Torvalds 3957aa91e10SKen Chen i_size_write(inode, offset); 39683cde9e8SDavidlohr Bueso i_mmap_lock_write(mapping); 3976b2dbba8SMichel Lespinasse if (!RB_EMPTY_ROOT(&mapping->i_mmap)) 3981bfad99aSMike Kravetz hugetlb_vmdelete_list(&mapping->i_mmap, pgoff, 0); 39983cde9e8SDavidlohr Bueso i_mmap_unlock_write(mapping); 400b45b5bd6SDavid Gibson truncate_hugepages(inode, offset); 4011da177e4SLinus Torvalds return 0; 4021da177e4SLinus Torvalds } 4031da177e4SLinus Torvalds 4041da177e4SLinus Torvalds static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) 4051da177e4SLinus Torvalds { 4062b0143b5SDavid Howells struct inode *inode = d_inode(dentry); 407a5516438SAndi Kleen struct hstate *h = hstate_inode(inode); 4081da177e4SLinus Torvalds int error; 4091da177e4SLinus Torvalds unsigned int ia_valid = attr->ia_valid; 4101da177e4SLinus Torvalds 4111da177e4SLinus Torvalds BUG_ON(!inode); 4121da177e4SLinus Torvalds 4131da177e4SLinus Torvalds error = inode_change_ok(inode, attr); 4141da177e4SLinus Torvalds if (error) 4151025774cSChristoph Hellwig return error; 4161da177e4SLinus Torvalds 4171da177e4SLinus Torvalds if (ia_valid & ATTR_SIZE) { 4181da177e4SLinus Torvalds error = -EINVAL; 4191025774cSChristoph Hellwig if (attr->ia_size & ~huge_page_mask(h)) 4201025774cSChristoph Hellwig return -EINVAL; 4211da177e4SLinus Torvalds error = hugetlb_vmtruncate(inode, attr->ia_size); 4221da177e4SLinus Torvalds if (error) 4231da177e4SLinus Torvalds return error; 4241da177e4SLinus Torvalds } 4251da177e4SLinus Torvalds 4261025774cSChristoph Hellwig setattr_copy(inode, attr); 4271025774cSChristoph Hellwig mark_inode_dirty(inode); 4281025774cSChristoph Hellwig return 0; 4291025774cSChristoph Hellwig } 4301025774cSChristoph Hellwig 4317d54fa64SAl Viro static struct inode *hugetlbfs_get_root(struct super_block *sb, 4327d54fa64SAl Viro struct hugetlbfs_config *config) 4331da177e4SLinus Torvalds { 4341da177e4SLinus Torvalds struct inode *inode; 4351da177e4SLinus Torvalds 4361da177e4SLinus Torvalds inode = new_inode(sb); 4371da177e4SLinus Torvalds if (inode) { 4381da177e4SLinus Torvalds struct hugetlbfs_inode_info *info; 43985fe4025SChristoph Hellwig inode->i_ino = get_next_ino(); 4407d54fa64SAl Viro inode->i_mode = S_IFDIR | config->mode; 4417d54fa64SAl Viro inode->i_uid = config->uid; 4427d54fa64SAl Viro inode->i_gid = config->gid; 4437d54fa64SAl Viro inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; 4447d54fa64SAl Viro info = HUGETLBFS_I(inode); 4457d54fa64SAl Viro mpol_shared_policy_init(&info->policy, NULL); 4467d54fa64SAl Viro inode->i_op = &hugetlbfs_dir_inode_operations; 4477d54fa64SAl Viro inode->i_fop = &simple_dir_operations; 4487d54fa64SAl Viro /* directory inodes start off with i_nlink == 2 (for "." entry) */ 4497d54fa64SAl Viro inc_nlink(inode); 45065ed7601SAneesh Kumar K.V lockdep_annotate_inode_mutex_key(inode); 4517d54fa64SAl Viro } 4527d54fa64SAl Viro return inode; 4537d54fa64SAl Viro } 4547d54fa64SAl Viro 455b610ded7SMichal Hocko /* 456c8c06efaSDavidlohr Bueso * Hugetlbfs is not reclaimable; therefore its i_mmap_rwsem will never 457b610ded7SMichal Hocko * be taken from reclaim -- unlike regular filesystems. This needs an 458b610ded7SMichal Hocko * annotation because huge_pmd_share() does an allocation under 459c8c06efaSDavidlohr Bueso * i_mmap_rwsem. 460b610ded7SMichal Hocko */ 461c8c06efaSDavidlohr Bueso static struct lock_class_key hugetlbfs_i_mmap_rwsem_key; 462b610ded7SMichal Hocko 4637d54fa64SAl Viro static struct inode *hugetlbfs_get_inode(struct super_block *sb, 4647d54fa64SAl Viro struct inode *dir, 46518df2252SAl Viro umode_t mode, dev_t dev) 4667d54fa64SAl Viro { 4677d54fa64SAl Viro struct inode *inode; 4689119a41eSJoonsoo Kim struct resv_map *resv_map; 4699119a41eSJoonsoo Kim 4709119a41eSJoonsoo Kim resv_map = resv_map_alloc(); 4719119a41eSJoonsoo Kim if (!resv_map) 4729119a41eSJoonsoo Kim return NULL; 4737d54fa64SAl Viro 4747d54fa64SAl Viro inode = new_inode(sb); 4757d54fa64SAl Viro if (inode) { 4767d54fa64SAl Viro struct hugetlbfs_inode_info *info; 4777d54fa64SAl Viro inode->i_ino = get_next_ino(); 4787d54fa64SAl Viro inode_init_owner(inode, dir, mode); 479c8c06efaSDavidlohr Bueso lockdep_set_class(&inode->i_mapping->i_mmap_rwsem, 480c8c06efaSDavidlohr Bueso &hugetlbfs_i_mmap_rwsem_key); 4811da177e4SLinus Torvalds inode->i_mapping->a_ops = &hugetlbfs_aops; 4821da177e4SLinus Torvalds inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; 4839119a41eSJoonsoo Kim inode->i_mapping->private_data = resv_map; 4841da177e4SLinus Torvalds info = HUGETLBFS_I(inode); 4856bfde05bSEric B Munson /* 4866bfde05bSEric B Munson * The policy is initialized here even if we are creating a 4876bfde05bSEric B Munson * private inode because initialization simply creates an 4886bfde05bSEric B Munson * an empty rb tree and calls spin_lock_init(), later when we 4896bfde05bSEric B Munson * call mpol_free_shared_policy() it will just return because 4906bfde05bSEric B Munson * the rb tree will still be empty. 4916bfde05bSEric B Munson */ 49271fe804bSLee Schermerhorn mpol_shared_policy_init(&info->policy, NULL); 4931da177e4SLinus Torvalds switch (mode & S_IFMT) { 4941da177e4SLinus Torvalds default: 4951da177e4SLinus Torvalds init_special_inode(inode, mode, dev); 4961da177e4SLinus Torvalds break; 4971da177e4SLinus Torvalds case S_IFREG: 4981da177e4SLinus Torvalds inode->i_op = &hugetlbfs_inode_operations; 4991da177e4SLinus Torvalds inode->i_fop = &hugetlbfs_file_operations; 5001da177e4SLinus Torvalds break; 5011da177e4SLinus Torvalds case S_IFDIR: 5021da177e4SLinus Torvalds inode->i_op = &hugetlbfs_dir_inode_operations; 5031da177e4SLinus Torvalds inode->i_fop = &simple_dir_operations; 5041da177e4SLinus Torvalds 5051da177e4SLinus Torvalds /* directory inodes start off with i_nlink == 2 (for "." entry) */ 506d8c76e6fSDave Hansen inc_nlink(inode); 5071da177e4SLinus Torvalds break; 5081da177e4SLinus Torvalds case S_IFLNK: 5091da177e4SLinus Torvalds inode->i_op = &page_symlink_inode_operations; 5101da177e4SLinus Torvalds break; 5111da177e4SLinus Torvalds } 512e096d0c7SJosh Boyer lockdep_annotate_inode_mutex_key(inode); 5139119a41eSJoonsoo Kim } else 5149119a41eSJoonsoo Kim kref_put(&resv_map->refs, resv_map_release); 5159119a41eSJoonsoo Kim 5161da177e4SLinus Torvalds return inode; 5171da177e4SLinus Torvalds } 5181da177e4SLinus Torvalds 5191da177e4SLinus Torvalds /* 5201da177e4SLinus Torvalds * File creation. Allocate an inode, and we're done.. 5211da177e4SLinus Torvalds */ 5221da177e4SLinus Torvalds static int hugetlbfs_mknod(struct inode *dir, 5231a67aafbSAl Viro struct dentry *dentry, umode_t mode, dev_t dev) 5241da177e4SLinus Torvalds { 5251da177e4SLinus Torvalds struct inode *inode; 5261da177e4SLinus Torvalds int error = -ENOSPC; 5271da177e4SLinus Torvalds 5287d54fa64SAl Viro inode = hugetlbfs_get_inode(dir->i_sb, dir, mode, dev); 5291da177e4SLinus Torvalds if (inode) { 5301da177e4SLinus Torvalds dir->i_ctime = dir->i_mtime = CURRENT_TIME; 5311da177e4SLinus Torvalds d_instantiate(dentry, inode); 5321da177e4SLinus Torvalds dget(dentry); /* Extra count - pin the dentry in core */ 5331da177e4SLinus Torvalds error = 0; 5341da177e4SLinus Torvalds } 5351da177e4SLinus Torvalds return error; 5361da177e4SLinus Torvalds } 5371da177e4SLinus Torvalds 53818bb1db3SAl Viro static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 5391da177e4SLinus Torvalds { 5401da177e4SLinus Torvalds int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0); 5411da177e4SLinus Torvalds if (!retval) 542d8c76e6fSDave Hansen inc_nlink(dir); 5431da177e4SLinus Torvalds return retval; 5441da177e4SLinus Torvalds } 5451da177e4SLinus Torvalds 546ebfc3b49SAl Viro static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) 5471da177e4SLinus Torvalds { 5481da177e4SLinus Torvalds return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0); 5491da177e4SLinus Torvalds } 5501da177e4SLinus Torvalds 5511da177e4SLinus Torvalds static int hugetlbfs_symlink(struct inode *dir, 5521da177e4SLinus Torvalds struct dentry *dentry, const char *symname) 5531da177e4SLinus Torvalds { 5541da177e4SLinus Torvalds struct inode *inode; 5551da177e4SLinus Torvalds int error = -ENOSPC; 5561da177e4SLinus Torvalds 5577d54fa64SAl Viro inode = hugetlbfs_get_inode(dir->i_sb, dir, S_IFLNK|S_IRWXUGO, 0); 5581da177e4SLinus Torvalds if (inode) { 5591da177e4SLinus Torvalds int l = strlen(symname)+1; 5601da177e4SLinus Torvalds error = page_symlink(inode, symname, l); 5611da177e4SLinus Torvalds if (!error) { 5621da177e4SLinus Torvalds d_instantiate(dentry, inode); 5631da177e4SLinus Torvalds dget(dentry); 5641da177e4SLinus Torvalds } else 5651da177e4SLinus Torvalds iput(inode); 5661da177e4SLinus Torvalds } 5671da177e4SLinus Torvalds dir->i_ctime = dir->i_mtime = CURRENT_TIME; 5681da177e4SLinus Torvalds 5691da177e4SLinus Torvalds return error; 5701da177e4SLinus Torvalds } 5711da177e4SLinus Torvalds 5721da177e4SLinus Torvalds /* 5736649a386SKen Chen * mark the head page dirty 5741da177e4SLinus Torvalds */ 5751da177e4SLinus Torvalds static int hugetlbfs_set_page_dirty(struct page *page) 5761da177e4SLinus Torvalds { 577d85f3385SChristoph Lameter struct page *head = compound_head(page); 5786649a386SKen Chen 5796649a386SKen Chen SetPageDirty(head); 5801da177e4SLinus Torvalds return 0; 5811da177e4SLinus Torvalds } 5821da177e4SLinus Torvalds 583290408d4SNaoya Horiguchi static int hugetlbfs_migrate_page(struct address_space *mapping, 584b969c4abSMel Gorman struct page *newpage, struct page *page, 585a6bc32b8SMel Gorman enum migrate_mode mode) 586290408d4SNaoya Horiguchi { 587290408d4SNaoya Horiguchi int rc; 588290408d4SNaoya Horiguchi 589290408d4SNaoya Horiguchi rc = migrate_huge_page_move_mapping(mapping, newpage, page); 59078bd5209SRafael Aquini if (rc != MIGRATEPAGE_SUCCESS) 591290408d4SNaoya Horiguchi return rc; 592290408d4SNaoya Horiguchi migrate_page_copy(newpage, page); 593290408d4SNaoya Horiguchi 59478bd5209SRafael Aquini return MIGRATEPAGE_SUCCESS; 595290408d4SNaoya Horiguchi } 596290408d4SNaoya Horiguchi 597726c3342SDavid Howells static int hugetlbfs_statfs(struct dentry *dentry, struct kstatfs *buf) 5981da177e4SLinus Torvalds { 599726c3342SDavid Howells struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(dentry->d_sb); 6002b0143b5SDavid Howells struct hstate *h = hstate_inode(d_inode(dentry)); 6011da177e4SLinus Torvalds 6021da177e4SLinus Torvalds buf->f_type = HUGETLBFS_MAGIC; 603a5516438SAndi Kleen buf->f_bsize = huge_page_size(h); 6041da177e4SLinus Torvalds if (sbinfo) { 6051da177e4SLinus Torvalds spin_lock(&sbinfo->stat_lock); 60674a8a65cSDavid Gibson /* If no limits set, just report 0 for max/free/used 60774a8a65cSDavid Gibson * blocks, like simple_statfs() */ 60890481622SDavid Gibson if (sbinfo->spool) { 60990481622SDavid Gibson long free_pages; 61090481622SDavid Gibson 61190481622SDavid Gibson spin_lock(&sbinfo->spool->lock); 61290481622SDavid Gibson buf->f_blocks = sbinfo->spool->max_hpages; 61390481622SDavid Gibson free_pages = sbinfo->spool->max_hpages 61490481622SDavid Gibson - sbinfo->spool->used_hpages; 61590481622SDavid Gibson buf->f_bavail = buf->f_bfree = free_pages; 61690481622SDavid Gibson spin_unlock(&sbinfo->spool->lock); 6171da177e4SLinus Torvalds buf->f_files = sbinfo->max_inodes; 6181da177e4SLinus Torvalds buf->f_ffree = sbinfo->free_inodes; 61974a8a65cSDavid Gibson } 6201da177e4SLinus Torvalds spin_unlock(&sbinfo->stat_lock); 6211da177e4SLinus Torvalds } 6221da177e4SLinus Torvalds buf->f_namelen = NAME_MAX; 6231da177e4SLinus Torvalds return 0; 6241da177e4SLinus Torvalds } 6251da177e4SLinus Torvalds 6261da177e4SLinus Torvalds static void hugetlbfs_put_super(struct super_block *sb) 6271da177e4SLinus Torvalds { 6281da177e4SLinus Torvalds struct hugetlbfs_sb_info *sbi = HUGETLBFS_SB(sb); 6291da177e4SLinus Torvalds 6301da177e4SLinus Torvalds if (sbi) { 6311da177e4SLinus Torvalds sb->s_fs_info = NULL; 63290481622SDavid Gibson 63390481622SDavid Gibson if (sbi->spool) 63490481622SDavid Gibson hugepage_put_subpool(sbi->spool); 63590481622SDavid Gibson 6361da177e4SLinus Torvalds kfree(sbi); 6371da177e4SLinus Torvalds } 6381da177e4SLinus Torvalds } 6391da177e4SLinus Torvalds 64096527980SChristoph Hellwig static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info *sbinfo) 64196527980SChristoph Hellwig { 64296527980SChristoph Hellwig if (sbinfo->free_inodes >= 0) { 64396527980SChristoph Hellwig spin_lock(&sbinfo->stat_lock); 64496527980SChristoph Hellwig if (unlikely(!sbinfo->free_inodes)) { 64596527980SChristoph Hellwig spin_unlock(&sbinfo->stat_lock); 64696527980SChristoph Hellwig return 0; 64796527980SChristoph Hellwig } 64896527980SChristoph Hellwig sbinfo->free_inodes--; 64996527980SChristoph Hellwig spin_unlock(&sbinfo->stat_lock); 65096527980SChristoph Hellwig } 65196527980SChristoph Hellwig 65296527980SChristoph Hellwig return 1; 65396527980SChristoph Hellwig } 65496527980SChristoph Hellwig 65596527980SChristoph Hellwig static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info *sbinfo) 65696527980SChristoph Hellwig { 65796527980SChristoph Hellwig if (sbinfo->free_inodes >= 0) { 65896527980SChristoph Hellwig spin_lock(&sbinfo->stat_lock); 65996527980SChristoph Hellwig sbinfo->free_inodes++; 66096527980SChristoph Hellwig spin_unlock(&sbinfo->stat_lock); 66196527980SChristoph Hellwig } 66296527980SChristoph Hellwig } 66396527980SChristoph Hellwig 66496527980SChristoph Hellwig 665e18b890bSChristoph Lameter static struct kmem_cache *hugetlbfs_inode_cachep; 6661da177e4SLinus Torvalds 6671da177e4SLinus Torvalds static struct inode *hugetlbfs_alloc_inode(struct super_block *sb) 6681da177e4SLinus Torvalds { 66996527980SChristoph Hellwig struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb); 6701da177e4SLinus Torvalds struct hugetlbfs_inode_info *p; 6711da177e4SLinus Torvalds 67296527980SChristoph Hellwig if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo))) 6731da177e4SLinus Torvalds return NULL; 674e94b1766SChristoph Lameter p = kmem_cache_alloc(hugetlbfs_inode_cachep, GFP_KERNEL); 67596527980SChristoph Hellwig if (unlikely(!p)) { 67696527980SChristoph Hellwig hugetlbfs_inc_free_inodes(sbinfo); 67796527980SChristoph Hellwig return NULL; 6781da177e4SLinus Torvalds } 67996527980SChristoph Hellwig return &p->vfs_inode; 6801da177e4SLinus Torvalds } 6811da177e4SLinus Torvalds 682fa0d7e3dSNick Piggin static void hugetlbfs_i_callback(struct rcu_head *head) 683fa0d7e3dSNick Piggin { 684fa0d7e3dSNick Piggin struct inode *inode = container_of(head, struct inode, i_rcu); 685fa0d7e3dSNick Piggin kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode)); 686fa0d7e3dSNick Piggin } 687fa0d7e3dSNick Piggin 6881da177e4SLinus Torvalds static void hugetlbfs_destroy_inode(struct inode *inode) 6891da177e4SLinus Torvalds { 69096527980SChristoph Hellwig hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode->i_sb)); 6911da177e4SLinus Torvalds mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy); 692fa0d7e3dSNick Piggin call_rcu(&inode->i_rcu, hugetlbfs_i_callback); 6931da177e4SLinus Torvalds } 6941da177e4SLinus Torvalds 695f5e54d6eSChristoph Hellwig static const struct address_space_operations hugetlbfs_aops = { 696800d15a5SNick Piggin .write_begin = hugetlbfs_write_begin, 697800d15a5SNick Piggin .write_end = hugetlbfs_write_end, 6981da177e4SLinus Torvalds .set_page_dirty = hugetlbfs_set_page_dirty, 699290408d4SNaoya Horiguchi .migratepage = hugetlbfs_migrate_page, 7001da177e4SLinus Torvalds }; 7011da177e4SLinus Torvalds 70296527980SChristoph Hellwig 70351cc5068SAlexey Dobriyan static void init_once(void *foo) 70496527980SChristoph Hellwig { 70596527980SChristoph Hellwig struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo; 70696527980SChristoph Hellwig 70796527980SChristoph Hellwig inode_init_once(&ei->vfs_inode); 70896527980SChristoph Hellwig } 70996527980SChristoph Hellwig 7104b6f5d20SArjan van de Ven const struct file_operations hugetlbfs_file_operations = { 71134d0640eSAl Viro .read_iter = hugetlbfs_read_iter, 7121da177e4SLinus Torvalds .mmap = hugetlbfs_file_mmap, 7131b061d92SChristoph Hellwig .fsync = noop_fsync, 7141da177e4SLinus Torvalds .get_unmapped_area = hugetlb_get_unmapped_area, 7156038f373SArnd Bergmann .llseek = default_llseek, 7161da177e4SLinus Torvalds }; 7171da177e4SLinus Torvalds 71892e1d5beSArjan van de Ven static const struct inode_operations hugetlbfs_dir_inode_operations = { 7191da177e4SLinus Torvalds .create = hugetlbfs_create, 7201da177e4SLinus Torvalds .lookup = simple_lookup, 7211da177e4SLinus Torvalds .link = simple_link, 7221da177e4SLinus Torvalds .unlink = simple_unlink, 7231da177e4SLinus Torvalds .symlink = hugetlbfs_symlink, 7241da177e4SLinus Torvalds .mkdir = hugetlbfs_mkdir, 7251da177e4SLinus Torvalds .rmdir = simple_rmdir, 7261da177e4SLinus Torvalds .mknod = hugetlbfs_mknod, 7271da177e4SLinus Torvalds .rename = simple_rename, 7281da177e4SLinus Torvalds .setattr = hugetlbfs_setattr, 7291da177e4SLinus Torvalds }; 7301da177e4SLinus Torvalds 73192e1d5beSArjan van de Ven static const struct inode_operations hugetlbfs_inode_operations = { 7321da177e4SLinus Torvalds .setattr = hugetlbfs_setattr, 7331da177e4SLinus Torvalds }; 7341da177e4SLinus Torvalds 735ee9b6d61SJosef 'Jeff' Sipek static const struct super_operations hugetlbfs_ops = { 7361da177e4SLinus Torvalds .alloc_inode = hugetlbfs_alloc_inode, 7371da177e4SLinus Torvalds .destroy_inode = hugetlbfs_destroy_inode, 7382bbbda30SAl Viro .evict_inode = hugetlbfs_evict_inode, 7391da177e4SLinus Torvalds .statfs = hugetlbfs_statfs, 7401da177e4SLinus Torvalds .put_super = hugetlbfs_put_super, 74110f19a86SMiklos Szeredi .show_options = generic_show_options, 7421da177e4SLinus Torvalds }; 7431da177e4SLinus Torvalds 7447ca02d0aSMike Kravetz enum { NO_SIZE, SIZE_STD, SIZE_PERCENT }; 7457ca02d0aSMike Kravetz 7467ca02d0aSMike Kravetz /* 7477ca02d0aSMike Kravetz * Convert size option passed from command line to number of huge pages 7487ca02d0aSMike Kravetz * in the pool specified by hstate. Size option could be in bytes 7497ca02d0aSMike Kravetz * (val_type == SIZE_STD) or percentage of the pool (val_type == SIZE_PERCENT). 7507ca02d0aSMike Kravetz */ 7517ca02d0aSMike Kravetz static long long 7527ca02d0aSMike Kravetz hugetlbfs_size_to_hpages(struct hstate *h, unsigned long long size_opt, 7537ca02d0aSMike Kravetz int val_type) 7547ca02d0aSMike Kravetz { 7557ca02d0aSMike Kravetz if (val_type == NO_SIZE) 7567ca02d0aSMike Kravetz return -1; 7577ca02d0aSMike Kravetz 7587ca02d0aSMike Kravetz if (val_type == SIZE_PERCENT) { 7597ca02d0aSMike Kravetz size_opt <<= huge_page_shift(h); 7607ca02d0aSMike Kravetz size_opt *= h->max_huge_pages; 7617ca02d0aSMike Kravetz do_div(size_opt, 100); 7627ca02d0aSMike Kravetz } 7637ca02d0aSMike Kravetz 7647ca02d0aSMike Kravetz size_opt >>= huge_page_shift(h); 7657ca02d0aSMike Kravetz return size_opt; 7667ca02d0aSMike Kravetz } 7677ca02d0aSMike Kravetz 7681da177e4SLinus Torvalds static int 7691da177e4SLinus Torvalds hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) 7701da177e4SLinus Torvalds { 771e73a75faSRandy Dunlap char *p, *rest; 772e73a75faSRandy Dunlap substring_t args[MAX_OPT_ARGS]; 773e73a75faSRandy Dunlap int option; 7747ca02d0aSMike Kravetz unsigned long long max_size_opt = 0, min_size_opt = 0; 7757ca02d0aSMike Kravetz int max_val_type = NO_SIZE, min_val_type = NO_SIZE; 7761da177e4SLinus Torvalds 7771da177e4SLinus Torvalds if (!options) 7781da177e4SLinus Torvalds return 0; 7791da177e4SLinus Torvalds 780e73a75faSRandy Dunlap while ((p = strsep(&options, ",")) != NULL) { 781e73a75faSRandy Dunlap int token; 782b4c07bceSLee Schermerhorn if (!*p) 783b4c07bceSLee Schermerhorn continue; 7841da177e4SLinus Torvalds 785e73a75faSRandy Dunlap token = match_token(p, tokens, args); 786e73a75faSRandy Dunlap switch (token) { 787e73a75faSRandy Dunlap case Opt_uid: 788e73a75faSRandy Dunlap if (match_int(&args[0], &option)) 789e73a75faSRandy Dunlap goto bad_val; 790a0eb3a05SEric W. Biederman pconfig->uid = make_kuid(current_user_ns(), option); 791a0eb3a05SEric W. Biederman if (!uid_valid(pconfig->uid)) 792a0eb3a05SEric W. Biederman goto bad_val; 793e73a75faSRandy Dunlap break; 794e73a75faSRandy Dunlap 795e73a75faSRandy Dunlap case Opt_gid: 796e73a75faSRandy Dunlap if (match_int(&args[0], &option)) 797e73a75faSRandy Dunlap goto bad_val; 798a0eb3a05SEric W. Biederman pconfig->gid = make_kgid(current_user_ns(), option); 799a0eb3a05SEric W. Biederman if (!gid_valid(pconfig->gid)) 800a0eb3a05SEric W. Biederman goto bad_val; 801e73a75faSRandy Dunlap break; 802e73a75faSRandy Dunlap 803e73a75faSRandy Dunlap case Opt_mode: 804e73a75faSRandy Dunlap if (match_octal(&args[0], &option)) 805e73a75faSRandy Dunlap goto bad_val; 80675897d60SKen Chen pconfig->mode = option & 01777U; 807e73a75faSRandy Dunlap break; 808e73a75faSRandy Dunlap 809e73a75faSRandy Dunlap case Opt_size: { 810e73a75faSRandy Dunlap /* memparse() will accept a K/M/G without a digit */ 811e73a75faSRandy Dunlap if (!isdigit(*args[0].from)) 812e73a75faSRandy Dunlap goto bad_val; 8137ca02d0aSMike Kravetz max_size_opt = memparse(args[0].from, &rest); 8147ca02d0aSMike Kravetz max_val_type = SIZE_STD; 815a137e1ccSAndi Kleen if (*rest == '%') 8167ca02d0aSMike Kravetz max_val_type = SIZE_PERCENT; 817e73a75faSRandy Dunlap break; 818e73a75faSRandy Dunlap } 8191da177e4SLinus Torvalds 820e73a75faSRandy Dunlap case Opt_nr_inodes: 821e73a75faSRandy Dunlap /* memparse() will accept a K/M/G without a digit */ 822e73a75faSRandy Dunlap if (!isdigit(*args[0].from)) 823e73a75faSRandy Dunlap goto bad_val; 824e73a75faSRandy Dunlap pconfig->nr_inodes = memparse(args[0].from, &rest); 825e73a75faSRandy Dunlap break; 826e73a75faSRandy Dunlap 827a137e1ccSAndi Kleen case Opt_pagesize: { 828a137e1ccSAndi Kleen unsigned long ps; 829a137e1ccSAndi Kleen ps = memparse(args[0].from, &rest); 830a137e1ccSAndi Kleen pconfig->hstate = size_to_hstate(ps); 831a137e1ccSAndi Kleen if (!pconfig->hstate) { 8329b857d26SAndrew Morton pr_err("Unsupported page size %lu MB\n", 833a137e1ccSAndi Kleen ps >> 20); 834a137e1ccSAndi Kleen return -EINVAL; 835a137e1ccSAndi Kleen } 836a137e1ccSAndi Kleen break; 837a137e1ccSAndi Kleen } 838a137e1ccSAndi Kleen 8397ca02d0aSMike Kravetz case Opt_min_size: { 8407ca02d0aSMike Kravetz /* memparse() will accept a K/M/G without a digit */ 8417ca02d0aSMike Kravetz if (!isdigit(*args[0].from)) 8427ca02d0aSMike Kravetz goto bad_val; 8437ca02d0aSMike Kravetz min_size_opt = memparse(args[0].from, &rest); 8447ca02d0aSMike Kravetz min_val_type = SIZE_STD; 8457ca02d0aSMike Kravetz if (*rest == '%') 8467ca02d0aSMike Kravetz min_val_type = SIZE_PERCENT; 8477ca02d0aSMike Kravetz break; 8487ca02d0aSMike Kravetz } 8497ca02d0aSMike Kravetz 850e73a75faSRandy Dunlap default: 8519b857d26SAndrew Morton pr_err("Bad mount option: \"%s\"\n", p); 852b4c07bceSLee Schermerhorn return -EINVAL; 853e73a75faSRandy Dunlap break; 854e73a75faSRandy Dunlap } 8551da177e4SLinus Torvalds } 856a137e1ccSAndi Kleen 8577ca02d0aSMike Kravetz /* 8587ca02d0aSMike Kravetz * Use huge page pool size (in hstate) to convert the size 8597ca02d0aSMike Kravetz * options to number of huge pages. If NO_SIZE, -1 is returned. 8607ca02d0aSMike Kravetz */ 8617ca02d0aSMike Kravetz pconfig->max_hpages = hugetlbfs_size_to_hpages(pconfig->hstate, 8627ca02d0aSMike Kravetz max_size_opt, max_val_type); 8637ca02d0aSMike Kravetz pconfig->min_hpages = hugetlbfs_size_to_hpages(pconfig->hstate, 8647ca02d0aSMike Kravetz min_size_opt, min_val_type); 8657ca02d0aSMike Kravetz 8667ca02d0aSMike Kravetz /* 8677ca02d0aSMike Kravetz * If max_size was specified, then min_size must be smaller 8687ca02d0aSMike Kravetz */ 8697ca02d0aSMike Kravetz if (max_val_type > NO_SIZE && 8707ca02d0aSMike Kravetz pconfig->min_hpages > pconfig->max_hpages) { 8717ca02d0aSMike Kravetz pr_err("minimum size can not be greater than maximum size\n"); 8727ca02d0aSMike Kravetz return -EINVAL; 873a137e1ccSAndi Kleen } 874a137e1ccSAndi Kleen 8751da177e4SLinus Torvalds return 0; 876e73a75faSRandy Dunlap 877e73a75faSRandy Dunlap bad_val: 8789b857d26SAndrew Morton pr_err("Bad value '%s' for mount option '%s'\n", args[0].from, p); 879c12ddba0SAkinobu Mita return -EINVAL; 8801da177e4SLinus Torvalds } 8811da177e4SLinus Torvalds 8821da177e4SLinus Torvalds static int 8831da177e4SLinus Torvalds hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) 8841da177e4SLinus Torvalds { 8851da177e4SLinus Torvalds int ret; 8861da177e4SLinus Torvalds struct hugetlbfs_config config; 8871da177e4SLinus Torvalds struct hugetlbfs_sb_info *sbinfo; 8881da177e4SLinus Torvalds 88910f19a86SMiklos Szeredi save_mount_options(sb, data); 89010f19a86SMiklos Szeredi 8917ca02d0aSMike Kravetz config.max_hpages = -1; /* No limit on size by default */ 8921da177e4SLinus Torvalds config.nr_inodes = -1; /* No limit on number of inodes by default */ 89377c70de1SDavid Howells config.uid = current_fsuid(); 89477c70de1SDavid Howells config.gid = current_fsgid(); 8951da177e4SLinus Torvalds config.mode = 0755; 896a137e1ccSAndi Kleen config.hstate = &default_hstate; 8977ca02d0aSMike Kravetz config.min_hpages = -1; /* No default minimum size */ 8981da177e4SLinus Torvalds ret = hugetlbfs_parse_options(data, &config); 8991da177e4SLinus Torvalds if (ret) 9001da177e4SLinus Torvalds return ret; 9011da177e4SLinus Torvalds 9021da177e4SLinus Torvalds sbinfo = kmalloc(sizeof(struct hugetlbfs_sb_info), GFP_KERNEL); 9031da177e4SLinus Torvalds if (!sbinfo) 9041da177e4SLinus Torvalds return -ENOMEM; 9051da177e4SLinus Torvalds sb->s_fs_info = sbinfo; 906a137e1ccSAndi Kleen sbinfo->hstate = config.hstate; 9071da177e4SLinus Torvalds spin_lock_init(&sbinfo->stat_lock); 9081da177e4SLinus Torvalds sbinfo->max_inodes = config.nr_inodes; 9091da177e4SLinus Torvalds sbinfo->free_inodes = config.nr_inodes; 91090481622SDavid Gibson sbinfo->spool = NULL; 9117ca02d0aSMike Kravetz /* 9127ca02d0aSMike Kravetz * Allocate and initialize subpool if maximum or minimum size is 9137ca02d0aSMike Kravetz * specified. Any needed reservations (for minimim size) are taken 9147ca02d0aSMike Kravetz * taken when the subpool is created. 9157ca02d0aSMike Kravetz */ 9167ca02d0aSMike Kravetz if (config.max_hpages != -1 || config.min_hpages != -1) { 9177ca02d0aSMike Kravetz sbinfo->spool = hugepage_new_subpool(config.hstate, 9187ca02d0aSMike Kravetz config.max_hpages, 9197ca02d0aSMike Kravetz config.min_hpages); 92090481622SDavid Gibson if (!sbinfo->spool) 92190481622SDavid Gibson goto out_free; 92290481622SDavid Gibson } 9231da177e4SLinus Torvalds sb->s_maxbytes = MAX_LFS_FILESIZE; 924a137e1ccSAndi Kleen sb->s_blocksize = huge_page_size(config.hstate); 925a137e1ccSAndi Kleen sb->s_blocksize_bits = huge_page_shift(config.hstate); 9261da177e4SLinus Torvalds sb->s_magic = HUGETLBFS_MAGIC; 9271da177e4SLinus Torvalds sb->s_op = &hugetlbfs_ops; 9281da177e4SLinus Torvalds sb->s_time_gran = 1; 92948fde701SAl Viro sb->s_root = d_make_root(hugetlbfs_get_root(sb, &config)); 93048fde701SAl Viro if (!sb->s_root) 9311da177e4SLinus Torvalds goto out_free; 9321da177e4SLinus Torvalds return 0; 9331da177e4SLinus Torvalds out_free: 93490481622SDavid Gibson kfree(sbinfo->spool); 9351da177e4SLinus Torvalds kfree(sbinfo); 9361da177e4SLinus Torvalds return -ENOMEM; 9371da177e4SLinus Torvalds } 9381da177e4SLinus Torvalds 9393c26ff6eSAl Viro static struct dentry *hugetlbfs_mount(struct file_system_type *fs_type, 9403c26ff6eSAl Viro int flags, const char *dev_name, void *data) 9411da177e4SLinus Torvalds { 9423c26ff6eSAl Viro return mount_nodev(fs_type, flags, data, hugetlbfs_fill_super); 9431da177e4SLinus Torvalds } 9441da177e4SLinus Torvalds 9451da177e4SLinus Torvalds static struct file_system_type hugetlbfs_fs_type = { 9461da177e4SLinus Torvalds .name = "hugetlbfs", 9473c26ff6eSAl Viro .mount = hugetlbfs_mount, 9481da177e4SLinus Torvalds .kill_sb = kill_litter_super, 9491da177e4SLinus Torvalds }; 9507f78e035SEric W. Biederman MODULE_ALIAS_FS("hugetlbfs"); 9511da177e4SLinus Torvalds 95242d7395fSAndi Kleen static struct vfsmount *hugetlbfs_vfsmount[HUGE_MAX_HSTATE]; 9531da177e4SLinus Torvalds 954ef1ff6b8SFrom: Mel Gorman static int can_do_hugetlb_shm(void) 9551da177e4SLinus Torvalds { 956a0eb3a05SEric W. Biederman kgid_t shm_group; 957a0eb3a05SEric W. Biederman shm_group = make_kgid(&init_user_ns, sysctl_hugetlb_shm_group); 958a0eb3a05SEric W. Biederman return capable(CAP_IPC_LOCK) || in_group_p(shm_group); 9591da177e4SLinus Torvalds } 9601da177e4SLinus Torvalds 96142d7395fSAndi Kleen static int get_hstate_idx(int page_size_log) 96242d7395fSAndi Kleen { 963af73e4d9SNaoya Horiguchi struct hstate *h = hstate_sizelog(page_size_log); 96442d7395fSAndi Kleen 96542d7395fSAndi Kleen if (!h) 96642d7395fSAndi Kleen return -1; 96742d7395fSAndi Kleen return h - hstates; 96842d7395fSAndi Kleen } 96942d7395fSAndi Kleen 970be1d2cf5SFabian Frederick static const struct dentry_operations anon_ops = { 971118b2302SAl Viro .d_dname = simple_dname 9720df4d6e5SAl Viro }; 9730df4d6e5SAl Viro 974af73e4d9SNaoya Horiguchi /* 975af73e4d9SNaoya Horiguchi * Note that size should be aligned to proper hugepage size in caller side, 976af73e4d9SNaoya Horiguchi * otherwise hugetlb_reserve_pages reserves one less hugepages than intended. 977af73e4d9SNaoya Horiguchi */ 978af73e4d9SNaoya Horiguchi struct file *hugetlb_file_setup(const char *name, size_t size, 979af73e4d9SNaoya Horiguchi vm_flags_t acctflag, struct user_struct **user, 98042d7395fSAndi Kleen int creat_flags, int page_size_log) 9811da177e4SLinus Torvalds { 98239b65252SAnatol Pomozov struct file *file = ERR_PTR(-ENOMEM); 9831da177e4SLinus Torvalds struct inode *inode; 9842c48b9c4SAl Viro struct path path; 9850df4d6e5SAl Viro struct super_block *sb; 9861da177e4SLinus Torvalds struct qstr quick_string; 98742d7395fSAndi Kleen int hstate_idx; 98842d7395fSAndi Kleen 98942d7395fSAndi Kleen hstate_idx = get_hstate_idx(page_size_log); 99042d7395fSAndi Kleen if (hstate_idx < 0) 99142d7395fSAndi Kleen return ERR_PTR(-ENODEV); 9921da177e4SLinus Torvalds 993353d5c30SHugh Dickins *user = NULL; 99442d7395fSAndi Kleen if (!hugetlbfs_vfsmount[hstate_idx]) 9955bc98594SAkinobu Mita return ERR_PTR(-ENOENT); 9965bc98594SAkinobu Mita 997ef1ff6b8SFrom: Mel Gorman if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) { 998353d5c30SHugh Dickins *user = current_user(); 999353d5c30SHugh Dickins if (user_shm_lock(size, *user)) { 100021a3c273SDavid Rientjes task_lock(current); 10019b857d26SAndrew Morton pr_warn_once("%s (%d): Using mlock ulimits for SHM_HUGETLB is deprecated\n", 100221a3c273SDavid Rientjes current->comm, current->pid); 100321a3c273SDavid Rientjes task_unlock(current); 1004353d5c30SHugh Dickins } else { 1005353d5c30SHugh Dickins *user = NULL; 10061da177e4SLinus Torvalds return ERR_PTR(-EPERM); 10072584e517SRavikiran G Thirumalai } 1008353d5c30SHugh Dickins } 10091da177e4SLinus Torvalds 10100df4d6e5SAl Viro sb = hugetlbfs_vfsmount[hstate_idx]->mnt_sb; 10119d66586fSEric W. Biederman quick_string.name = name; 10121da177e4SLinus Torvalds quick_string.len = strlen(quick_string.name); 10131da177e4SLinus Torvalds quick_string.hash = 0; 10140df4d6e5SAl Viro path.dentry = d_alloc_pseudo(sb, &quick_string); 10152c48b9c4SAl Viro if (!path.dentry) 10161da177e4SLinus Torvalds goto out_shm_unlock; 10171da177e4SLinus Torvalds 10180df4d6e5SAl Viro d_set_d_op(path.dentry, &anon_ops); 101942d7395fSAndi Kleen path.mnt = mntget(hugetlbfs_vfsmount[hstate_idx]); 102039b65252SAnatol Pomozov file = ERR_PTR(-ENOSPC); 10210df4d6e5SAl Viro inode = hugetlbfs_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0); 10221da177e4SLinus Torvalds if (!inode) 1023ce8d2cdfSDave Hansen goto out_dentry; 1024e1832f29SStephen Smalley if (creat_flags == HUGETLB_SHMFS_INODE) 1025e1832f29SStephen Smalley inode->i_flags |= S_PRIVATE; 10261da177e4SLinus Torvalds 102739b65252SAnatol Pomozov file = ERR_PTR(-ENOMEM); 1028af73e4d9SNaoya Horiguchi if (hugetlb_reserve_pages(inode, 0, 1029af73e4d9SNaoya Horiguchi size >> huge_page_shift(hstate_inode(inode)), NULL, 1030af73e4d9SNaoya Horiguchi acctflag)) 1031b45b5bd6SDavid Gibson goto out_inode; 1032b45b5bd6SDavid Gibson 10332c48b9c4SAl Viro d_instantiate(path.dentry, inode); 10341da177e4SLinus Torvalds inode->i_size = size; 10356d6b77f1SMiklos Szeredi clear_nlink(inode); 1036ce8d2cdfSDave Hansen 10372c48b9c4SAl Viro file = alloc_file(&path, FMODE_WRITE | FMODE_READ, 1038ce8d2cdfSDave Hansen &hugetlbfs_file_operations); 103939b65252SAnatol Pomozov if (IS_ERR(file)) 1040b4d232e6SAl Viro goto out_dentry; /* inode is already attached */ 1041ce8d2cdfSDave Hansen 10421da177e4SLinus Torvalds return file; 10431da177e4SLinus Torvalds 1044b45b5bd6SDavid Gibson out_inode: 1045b45b5bd6SDavid Gibson iput(inode); 10461da177e4SLinus Torvalds out_dentry: 10472c48b9c4SAl Viro path_put(&path); 10481da177e4SLinus Torvalds out_shm_unlock: 1049353d5c30SHugh Dickins if (*user) { 1050353d5c30SHugh Dickins user_shm_unlock(size, *user); 1051353d5c30SHugh Dickins *user = NULL; 1052353d5c30SHugh Dickins } 105339b65252SAnatol Pomozov return file; 10541da177e4SLinus Torvalds } 10551da177e4SLinus Torvalds 10561da177e4SLinus Torvalds static int __init init_hugetlbfs_fs(void) 10571da177e4SLinus Torvalds { 105842d7395fSAndi Kleen struct hstate *h; 10591da177e4SLinus Torvalds int error; 106042d7395fSAndi Kleen int i; 10611da177e4SLinus Torvalds 1062457c1b27SNishanth Aravamudan if (!hugepages_supported()) { 10639b857d26SAndrew Morton pr_info("disabling because there are no supported hugepage sizes\n"); 1064457c1b27SNishanth Aravamudan return -ENOTSUPP; 1065457c1b27SNishanth Aravamudan } 1066457c1b27SNishanth Aravamudan 1067d1d5e05fSHillf Danton error = -ENOMEM; 10681da177e4SLinus Torvalds hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache", 10691da177e4SLinus Torvalds sizeof(struct hugetlbfs_inode_info), 107020c2df83SPaul Mundt 0, 0, init_once); 10711da177e4SLinus Torvalds if (hugetlbfs_inode_cachep == NULL) 1072e0bf68ddSPeter Zijlstra goto out2; 10731da177e4SLinus Torvalds 10741da177e4SLinus Torvalds error = register_filesystem(&hugetlbfs_fs_type); 10751da177e4SLinus Torvalds if (error) 10761da177e4SLinus Torvalds goto out; 10771da177e4SLinus Torvalds 107842d7395fSAndi Kleen i = 0; 107942d7395fSAndi Kleen for_each_hstate(h) { 108042d7395fSAndi Kleen char buf[50]; 108142d7395fSAndi Kleen unsigned ps_kb = 1U << (h->order + PAGE_SHIFT - 10); 10821da177e4SLinus Torvalds 108342d7395fSAndi Kleen snprintf(buf, sizeof(buf), "pagesize=%uK", ps_kb); 108442d7395fSAndi Kleen hugetlbfs_vfsmount[i] = kern_mount_data(&hugetlbfs_fs_type, 108542d7395fSAndi Kleen buf); 108642d7395fSAndi Kleen 108742d7395fSAndi Kleen if (IS_ERR(hugetlbfs_vfsmount[i])) { 10889b857d26SAndrew Morton pr_err("Cannot mount internal hugetlbfs for " 108942d7395fSAndi Kleen "page size %uK", ps_kb); 109042d7395fSAndi Kleen error = PTR_ERR(hugetlbfs_vfsmount[i]); 109142d7395fSAndi Kleen hugetlbfs_vfsmount[i] = NULL; 10921da177e4SLinus Torvalds } 109342d7395fSAndi Kleen i++; 109442d7395fSAndi Kleen } 109542d7395fSAndi Kleen /* Non default hstates are optional */ 109642d7395fSAndi Kleen if (!IS_ERR_OR_NULL(hugetlbfs_vfsmount[default_hstate_idx])) 109742d7395fSAndi Kleen return 0; 10981da177e4SLinus Torvalds 10991da177e4SLinus Torvalds out: 11001da177e4SLinus Torvalds kmem_cache_destroy(hugetlbfs_inode_cachep); 1101e0bf68ddSPeter Zijlstra out2: 11021da177e4SLinus Torvalds return error; 11031da177e4SLinus Torvalds } 11041da177e4SLinus Torvalds 11051da177e4SLinus Torvalds static void __exit exit_hugetlbfs_fs(void) 11061da177e4SLinus Torvalds { 110742d7395fSAndi Kleen struct hstate *h; 110842d7395fSAndi Kleen int i; 110942d7395fSAndi Kleen 111042d7395fSAndi Kleen 11118c0a8537SKirill A. Shutemov /* 11128c0a8537SKirill A. Shutemov * Make sure all delayed rcu free inodes are flushed before we 11138c0a8537SKirill A. Shutemov * destroy cache. 11148c0a8537SKirill A. Shutemov */ 11158c0a8537SKirill A. Shutemov rcu_barrier(); 11161da177e4SLinus Torvalds kmem_cache_destroy(hugetlbfs_inode_cachep); 111742d7395fSAndi Kleen i = 0; 111842d7395fSAndi Kleen for_each_hstate(h) 111942d7395fSAndi Kleen kern_unmount(hugetlbfs_vfsmount[i++]); 11201da177e4SLinus Torvalds unregister_filesystem(&hugetlbfs_fs_type); 11211da177e4SLinus Torvalds } 11221da177e4SLinus Torvalds 11231da177e4SLinus Torvalds module_init(init_hugetlbfs_fs) 11241da177e4SLinus Torvalds module_exit(exit_hugetlbfs_fs) 11251da177e4SLinus Torvalds 11261da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 1127