| /* |
| * GPL HEADER START |
| * |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 only, |
| * as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License version 2 for more details (a copy is included |
| * in the LICENSE file that accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License |
| * version 2 along with this program; If not, see |
| * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf |
| * |
| * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| * |
| * GPL HEADER END |
| */ |
| /* |
| * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. |
| * Use is subject to license terms. |
| * |
| * Copyright (c) 2011, 2012, Intel Corporation. |
| */ |
| /* |
| * This file is part of Lustre, http://www.lustre.org/ |
| * Lustre is a trademark of Sun Microsystems, Inc. |
| * |
| * lustre/lustre/llite/rw26.c |
| * |
| * Lustre Lite I/O page cache routines for the 2.5/2.6 kernel version |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/string.h> |
| #include <linux/stat.h> |
| #include <linux/errno.h> |
| #include <linux/unistd.h> |
| #include <asm/uaccess.h> |
| |
| #include <linux/migrate.h> |
| #include <linux/fs.h> |
| #include <linux/buffer_head.h> |
| #include <linux/mpage.h> |
| #include <linux/writeback.h> |
| #include <linux/pagemap.h> |
| |
| #define DEBUG_SUBSYSTEM S_LLITE |
| |
| #include <lustre_lite.h> |
| #include "llite_internal.h" |
| #include <linux/lustre_compat25.h> |
| |
| /** |
| * Implements Linux VM address_space::invalidatepage() method. This method is |
| * called when the page is truncate from a file, either as a result of |
| * explicit truncate, or when inode is removed from memory (as a result of |
| * final iput(), umount, or memory pressure induced icache shrinking). |
| * |
| * [0, offset] bytes of the page remain valid (this is for a case of not-page |
| * aligned truncate). Lustre leaves partially truncated page in the cache, |
| * relying on struct inode::i_size to limit further accesses. |
| */ |
| static void ll_invalidatepage(struct page *vmpage, unsigned int offset, |
| unsigned int length) |
| { |
| struct inode *inode; |
| struct lu_env *env; |
| struct cl_page *page; |
| struct cl_object *obj; |
| |
| int refcheck; |
| |
| LASSERT(PageLocked(vmpage)); |
| LASSERT(!PageWriteback(vmpage)); |
| |
| /* |
| * It is safe to not check anything in invalidatepage/releasepage |
| * below because they are run with page locked and all our io is |
| * happening with locked page too |
| */ |
| if (offset == 0 && length == PAGE_CACHE_SIZE) { |
| env = cl_env_get(&refcheck); |
| if (!IS_ERR(env)) { |
| inode = vmpage->mapping->host; |
| obj = ll_i2info(inode)->lli_clob; |
| if (obj != NULL) { |
| page = cl_vmpage_page(vmpage, obj); |
| if (page != NULL) { |
| lu_ref_add(&page->cp_reference, |
| "delete", vmpage); |
| cl_page_delete(env, page); |
| lu_ref_del(&page->cp_reference, |
| "delete", vmpage); |
| cl_page_put(env, page); |
| } |
| } else |
| LASSERT(vmpage->private == 0); |
| cl_env_put(env, &refcheck); |
| } |
| } |
| } |
| |
| #ifdef HAVE_RELEASEPAGE_WITH_INT |
| #define RELEASEPAGE_ARG_TYPE int |
| #else |
| #define RELEASEPAGE_ARG_TYPE gfp_t |
| #endif |
| static int ll_releasepage(struct page *vmpage, RELEASEPAGE_ARG_TYPE gfp_mask) |
| { |
| struct cl_env_nest nest; |
| struct lu_env *env; |
| struct cl_object *obj; |
| struct cl_page *page; |
| struct address_space *mapping; |
| int result; |
| |
| LASSERT(PageLocked(vmpage)); |
| if (PageWriteback(vmpage) || PageDirty(vmpage)) |
| return 0; |
| |
| mapping = vmpage->mapping; |
| if (mapping == NULL) |
| return 1; |
| |
| obj = ll_i2info(mapping->host)->lli_clob; |
| if (obj == NULL) |
| return 1; |
| |
| /* 1 for page allocator, 1 for cl_page and 1 for page cache */ |
| if (page_count(vmpage) > 3) |
| return 0; |
| |
| /* TODO: determine what gfp should be used by @gfp_mask. */ |
| env = cl_env_nested_get(&nest); |
| if (IS_ERR(env)) |
| /* If we can't allocate an env we won't call cl_page_put() |
| * later on which further means it's impossible to drop |
| * page refcount by cl_page, so ask kernel to not free |
| * this page. */ |
| return 0; |
| |
| page = cl_vmpage_page(vmpage, obj); |
| result = page == NULL; |
| if (page != NULL) { |
| if (!cl_page_in_use(page)) { |
| result = 1; |
| cl_page_delete(env, page); |
| } |
| cl_page_put(env, page); |
| } |
| cl_env_nested_put(&nest, env); |
| return result; |
| } |
| |
| static int ll_set_page_dirty(struct page *vmpage) |
| { |
| #if 0 |
| struct cl_page *page = vvp_vmpage_page_transient(vmpage); |
| struct vvp_object *obj = cl_inode2vvp(vmpage->mapping->host); |
| struct vvp_page *cpg; |
| |
| /* |
| * XXX should page method be called here? |
| */ |
| LASSERT(&obj->co_cl == page->cp_obj); |
| cpg = cl2vvp_page(cl_page_at(page, &vvp_device_type)); |
| /* |
| * XXX cannot do much here, because page is possibly not locked: |
| * sys_munmap()->... |
| * ->unmap_page_range()->zap_pte_range()->set_page_dirty(). |
| */ |
| vvp_write_pending(obj, cpg); |
| #endif |
| return __set_page_dirty_nobuffers(vmpage); |
| } |
| |
| #define MAX_DIRECTIO_SIZE 2*1024*1024*1024UL |
| |
| static inline int ll_get_user_pages(int rw, unsigned long user_addr, |
| size_t size, struct page ***pages, |
| int *max_pages) |
| { |
| int result = -ENOMEM; |
| |
| /* set an arbitrary limit to prevent arithmetic overflow */ |
| if (size > MAX_DIRECTIO_SIZE) { |
| *pages = NULL; |
| return -EFBIG; |
| } |
| |
| *max_pages = (user_addr + size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; |
| *max_pages -= user_addr >> PAGE_CACHE_SHIFT; |
| |
| OBD_ALLOC_LARGE(*pages, *max_pages * sizeof(**pages)); |
| if (*pages) { |
| result = get_user_pages_fast(user_addr, *max_pages, |
| (rw == READ), *pages); |
| if (unlikely(result <= 0)) |
| OBD_FREE_LARGE(*pages, *max_pages * sizeof(**pages)); |
| } |
| |
| return result; |
| } |
| |
| /* ll_free_user_pages - tear down page struct array |
| * @pages: array of page struct pointers underlying target buffer */ |
| static void ll_free_user_pages(struct page **pages, int npages, int do_dirty) |
| { |
| int i; |
| |
| for (i = 0; i < npages; i++) { |
| if (pages[i] == NULL) |
| break; |
| if (do_dirty) |
| set_page_dirty_lock(pages[i]); |
| page_cache_release(pages[i]); |
| } |
| |
| OBD_FREE_LARGE(pages, npages * sizeof(*pages)); |
| } |
| |
| ssize_t ll_direct_rw_pages(const struct lu_env *env, struct cl_io *io, |
| int rw, struct inode *inode, |
| struct ll_dio_pages *pv) |
| { |
| struct cl_page *clp; |
| struct cl_2queue *queue; |
| struct cl_object *obj = io->ci_obj; |
| int i; |
| ssize_t rc = 0; |
| loff_t file_offset = pv->ldp_start_offset; |
| long size = pv->ldp_size; |
| int page_count = pv->ldp_nr; |
| struct page **pages = pv->ldp_pages; |
| long page_size = cl_page_size(obj); |
| bool do_io; |
| int io_pages = 0; |
| |
| queue = &io->ci_queue; |
| cl_2queue_init(queue); |
| for (i = 0; i < page_count; i++) { |
| if (pv->ldp_offsets) |
| file_offset = pv->ldp_offsets[i]; |
| |
| LASSERT(!(file_offset & (page_size - 1))); |
| clp = cl_page_find(env, obj, cl_index(obj, file_offset), |
| pv->ldp_pages[i], CPT_TRANSIENT); |
| if (IS_ERR(clp)) { |
| rc = PTR_ERR(clp); |
| break; |
| } |
| |
| rc = cl_page_own(env, io, clp); |
| if (rc) { |
| LASSERT(clp->cp_state == CPS_FREEING); |
| cl_page_put(env, clp); |
| break; |
| } |
| |
| do_io = true; |
| |
| /* check the page type: if the page is a host page, then do |
| * write directly */ |
| if (clp->cp_type == CPT_CACHEABLE) { |
| struct page *vmpage = cl_page_vmpage(env, clp); |
| struct page *src_page; |
| struct page *dst_page; |
| void *src; |
| void *dst; |
| |
| src_page = (rw == WRITE) ? pages[i] : vmpage; |
| dst_page = (rw == WRITE) ? vmpage : pages[i]; |
| |
| src = kmap_atomic(src_page); |
| dst = kmap_atomic(dst_page); |
| memcpy(dst, src, min(page_size, size)); |
| kunmap_atomic(dst); |
| kunmap_atomic(src); |
| |
| /* make sure page will be added to the transfer by |
| * cl_io_submit()->...->vvp_page_prep_write(). */ |
| if (rw == WRITE) |
| set_page_dirty(vmpage); |
| |
| if (rw == READ) { |
| /* do not issue the page for read, since it |
| * may reread a ra page which has NOT uptodate |
| * bit set. */ |
| cl_page_disown(env, io, clp); |
| do_io = false; |
| } |
| } |
| |
| if (likely(do_io)) { |
| cl_2queue_add(queue, clp); |
| |
| /* |
| * Set page clip to tell transfer formation engine |
| * that page has to be sent even if it is beyond KMS. |
| */ |
| cl_page_clip(env, clp, 0, min(size, page_size)); |
| |
| ++io_pages; |
| } |
| |
| /* drop the reference count for cl_page_find */ |
| cl_page_put(env, clp); |
| size -= page_size; |
| file_offset += page_size; |
| } |
| |
| if (rc == 0 && io_pages) { |
| rc = cl_io_submit_sync(env, io, |
| rw == READ ? CRT_READ : CRT_WRITE, |
| queue, 0); |
| } |
| if (rc == 0) |
| rc = pv->ldp_size; |
| |
| cl_2queue_discard(env, io, queue); |
| cl_2queue_disown(env, io, queue); |
| cl_2queue_fini(env, queue); |
| return rc; |
| } |
| EXPORT_SYMBOL(ll_direct_rw_pages); |
| |
| static ssize_t ll_direct_IO_26_seg(const struct lu_env *env, struct cl_io *io, |
| int rw, struct inode *inode, |
| struct address_space *mapping, |
| size_t size, loff_t file_offset, |
| struct page **pages, int page_count) |
| { |
| struct ll_dio_pages pvec = { .ldp_pages = pages, |
| .ldp_nr = page_count, |
| .ldp_size = size, |
| .ldp_offsets = NULL, |
| .ldp_start_offset = file_offset |
| }; |
| |
| return ll_direct_rw_pages(env, io, rw, inode, &pvec); |
| } |
| |
| #ifdef KMALLOC_MAX_SIZE |
| #define MAX_MALLOC KMALLOC_MAX_SIZE |
| #else |
| #define MAX_MALLOC (128 * 1024) |
| #endif |
| |
| /* This is the maximum size of a single O_DIRECT request, based on the |
| * kmalloc limit. We need to fit all of the brw_page structs, each one |
| * representing PAGE_SIZE worth of user data, into a single buffer, and |
| * then truncate this to be a full-sized RPC. For 4kB PAGE_SIZE this is |
| * up to 22MB for 128kB kmalloc and up to 682MB for 4MB kmalloc. */ |
| #define MAX_DIO_SIZE ((MAX_MALLOC / sizeof(struct brw_page) * PAGE_CACHE_SIZE) & \ |
| ~(DT_MAX_BRW_SIZE - 1)) |
| static ssize_t ll_direct_IO_26(int rw, struct kiocb *iocb, |
| const struct iovec *iov, loff_t file_offset, |
| unsigned long nr_segs) |
| { |
| struct lu_env *env; |
| struct cl_io *io; |
| struct file *file = iocb->ki_filp; |
| struct inode *inode = file->f_mapping->host; |
| struct ccc_object *obj = cl_inode2ccc(inode); |
| long count = iov_length(iov, nr_segs); |
| long tot_bytes = 0, result = 0; |
| struct ll_inode_info *lli = ll_i2info(inode); |
| unsigned long seg = 0; |
| long size = MAX_DIO_SIZE; |
| int refcheck; |
| |
| if (!lli->lli_has_smd) |
| return -EBADF; |
| |
| /* FIXME: io smaller than PAGE_SIZE is broken on ia64 ??? */ |
| if ((file_offset & ~CFS_PAGE_MASK) || (count & ~CFS_PAGE_MASK)) |
| return -EINVAL; |
| |
| CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p), size=%lu (max %lu), " |
| "offset=%lld=%llx, pages %lu (max %lu)\n", |
| inode->i_ino, inode->i_generation, inode, count, MAX_DIO_SIZE, |
| file_offset, file_offset, count >> PAGE_CACHE_SHIFT, |
| MAX_DIO_SIZE >> PAGE_CACHE_SHIFT); |
| |
| /* Check that all user buffers are aligned as well */ |
| for (seg = 0; seg < nr_segs; seg++) { |
| if (((unsigned long)iov[seg].iov_base & ~CFS_PAGE_MASK) || |
| (iov[seg].iov_len & ~CFS_PAGE_MASK)) |
| return -EINVAL; |
| } |
| |
| env = cl_env_get(&refcheck); |
| LASSERT(!IS_ERR(env)); |
| io = ccc_env_io(env)->cui_cl.cis_io; |
| LASSERT(io != NULL); |
| |
| /* 0. Need locking between buffered and direct access. and race with |
| * size changing by concurrent truncates and writes. |
| * 1. Need inode mutex to operate transient pages. |
| */ |
| if (rw == READ) |
| mutex_lock(&inode->i_mutex); |
| |
| LASSERT(obj->cob_transient_pages == 0); |
| for (seg = 0; seg < nr_segs; seg++) { |
| long iov_left = iov[seg].iov_len; |
| unsigned long user_addr = (unsigned long)iov[seg].iov_base; |
| |
| if (rw == READ) { |
| if (file_offset >= i_size_read(inode)) |
| break; |
| if (file_offset + iov_left > i_size_read(inode)) |
| iov_left = i_size_read(inode) - file_offset; |
| } |
| |
| while (iov_left > 0) { |
| struct page **pages; |
| int page_count, max_pages = 0; |
| long bytes; |
| |
| bytes = min(size, iov_left); |
| page_count = ll_get_user_pages(rw, user_addr, bytes, |
| &pages, &max_pages); |
| if (likely(page_count > 0)) { |
| if (unlikely(page_count < max_pages)) |
| bytes = page_count << PAGE_CACHE_SHIFT; |
| result = ll_direct_IO_26_seg(env, io, rw, inode, |
| file->f_mapping, |
| bytes, file_offset, |
| pages, page_count); |
| ll_free_user_pages(pages, max_pages, rw==READ); |
| } else if (page_count == 0) { |
| GOTO(out, result = -EFAULT); |
| } else { |
| result = page_count; |
| } |
| if (unlikely(result <= 0)) { |
| /* If we can't allocate a large enough buffer |
| * for the request, shrink it to a smaller |
| * PAGE_SIZE multiple and try again. |
| * We should always be able to kmalloc for a |
| * page worth of page pointers = 4MB on i386. */ |
| if (result == -ENOMEM && |
| size > (PAGE_CACHE_SIZE / sizeof(*pages)) * |
| PAGE_CACHE_SIZE) { |
| size = ((((size / 2) - 1) | |
| ~CFS_PAGE_MASK) + 1) & |
| CFS_PAGE_MASK; |
| CDEBUG(D_VFSTRACE,"DIO size now %lu\n", |
| size); |
| continue; |
| } |
| |
| GOTO(out, result); |
| } |
| |
| tot_bytes += result; |
| file_offset += result; |
| iov_left -= result; |
| user_addr += result; |
| } |
| } |
| out: |
| LASSERT(obj->cob_transient_pages == 0); |
| if (rw == READ) |
| mutex_unlock(&inode->i_mutex); |
| |
| if (tot_bytes > 0) { |
| if (rw == WRITE) { |
| struct lov_stripe_md *lsm; |
| |
| lsm = ccc_inode_lsm_get(inode); |
| LASSERT(lsm != NULL); |
| lov_stripe_lock(lsm); |
| obd_adjust_kms(ll_i2dtexp(inode), lsm, file_offset, 0); |
| lov_stripe_unlock(lsm); |
| ccc_inode_lsm_put(inode, lsm); |
| } |
| } |
| |
| cl_env_put(env, &refcheck); |
| return tot_bytes ? : result; |
| } |
| |
| static int ll_write_begin(struct file *file, struct address_space *mapping, |
| loff_t pos, unsigned len, unsigned flags, |
| struct page **pagep, void **fsdata) |
| { |
| pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
| struct page *page; |
| int rc; |
| unsigned from = pos & (PAGE_CACHE_SIZE - 1); |
| |
| page = grab_cache_page_write_begin(mapping, index, flags); |
| if (!page) |
| return -ENOMEM; |
| |
| *pagep = page; |
| |
| rc = ll_prepare_write(file, page, from, from + len); |
| if (rc) { |
| unlock_page(page); |
| page_cache_release(page); |
| } |
| return rc; |
| } |
| |
| static int ll_write_end(struct file *file, struct address_space *mapping, |
| loff_t pos, unsigned len, unsigned copied, |
| struct page *page, void *fsdata) |
| { |
| unsigned from = pos & (PAGE_CACHE_SIZE - 1); |
| int rc; |
| |
| rc = ll_commit_write(file, page, from, from + copied); |
| unlock_page(page); |
| page_cache_release(page); |
| |
| return rc ?: copied; |
| } |
| |
| #ifdef CONFIG_MIGRATION |
| int ll_migratepage(struct address_space *mapping, |
| struct page *newpage, struct page *page |
| , enum migrate_mode mode |
| ) |
| { |
| /* Always fail page migration until we have a proper implementation */ |
| return -EIO; |
| } |
| #endif |
| |
| #ifndef MS_HAS_NEW_AOPS |
| struct address_space_operations ll_aops = { |
| .readpage = ll_readpage, |
| // .readpages = ll_readpages, |
| .direct_IO = ll_direct_IO_26, |
| .writepage = ll_writepage, |
| .writepages = ll_writepages, |
| .set_page_dirty = ll_set_page_dirty, |
| .write_begin = ll_write_begin, |
| .write_end = ll_write_end, |
| .invalidatepage = ll_invalidatepage, |
| .releasepage = (void *)ll_releasepage, |
| #ifdef CONFIG_MIGRATION |
| .migratepage = ll_migratepage, |
| #endif |
| .bmap = NULL |
| }; |
| #else |
| struct address_space_operations_ext ll_aops = { |
| .orig_aops.readpage = ll_readpage, |
| // .orig_aops.readpages = ll_readpages, |
| .orig_aops.direct_IO = ll_direct_IO_26, |
| .orig_aops.writepage = ll_writepage, |
| .orig_aops.writepages = ll_writepages, |
| .orig_aops.set_page_dirty = ll_set_page_dirty, |
| .orig_aops.prepare_write = ll_prepare_write, |
| .orig_aops.commit_write = ll_commit_write, |
| .orig_aops.invalidatepage = ll_invalidatepage, |
| .orig_aops.releasepage = ll_releasepage, |
| #ifdef CONFIG_MIGRATION |
| .orig_aops.migratepage = ll_migratepage, |
| #endif |
| .orig_aops.bmap = NULL, |
| .write_begin = ll_write_begin, |
| .write_end = ll_write_end |
| }; |
| #endif |