--- /dev/null
+/*
+ * 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 <linux/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 "../include/lustre_lite.h"
+#include "llite_internal.h"
+#include "../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 (do_dirty)
+ set_page_dirty_lock(pages[i]);
+ page_cache_release(pages[i]);
+ }
+ kvfree(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(struct kiocb *iocb, struct iov_iter *iter,
+ loff_t file_offset)
+{
+ 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);
+ ssize_t count = iov_iter_count(iter);
+ ssize_t tot_bytes = 0, result = 0;
+ struct ll_inode_info *lli = ll_i2info(inode);
+ 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=%zd (max %lu), offset=%lld=%llx, pages %zd (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 */
+ if (iov_iter_alignment(iter) & ~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 (iov_iter_rw(iter) == READ)
+ mutex_lock(&inode->i_mutex);
+
+ LASSERT(obj->cob_transient_pages == 0);
+ while (iov_iter_count(iter)) {
+ struct page **pages;
+ size_t offs;
+
+ count = min_t(size_t, iov_iter_count(iter), size);
+ if (iov_iter_rw(iter) == READ) {
+ if (file_offset >= i_size_read(inode))
+ break;
+ if (file_offset + count > i_size_read(inode))
+ count = i_size_read(inode) - file_offset;
+ }
+
+ result = iov_iter_get_pages_alloc(iter, &pages, count, &offs);
+ if (likely(result > 0)) {
+ int n = DIV_ROUND_UP(result + offs, PAGE_SIZE);
+ result = ll_direct_IO_26_seg(env, io, iov_iter_rw(iter),
+ inode, file->f_mapping,
+ result, file_offset, pages,
+ n);
+ ll_free_user_pages(pages, n, iov_iter_rw(iter) == READ);
+ }
+ 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;
+ }
+ iov_iter_advance(iter, result);
+ tot_bytes += result;
+ file_offset += result;
+ }
+out:
+ LASSERT(obj->cob_transient_pages == 0);
+ if (iov_iter_rw(iter) == READ)
+ mutex_unlock(&inode->i_mutex);
+
+ if (tot_bytes > 0) {
+ if (iov_iter_rw(iter) == 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
+static 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
+const struct address_space_operations ll_aops = {
+ .readpage = ll_readpage,
+ .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
+};
+#else
+const 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
+ .write_begin = ll_write_begin,
+ .write_end = ll_write_end
+};
+#endif
Code Review / kvmfornfv.git / blobdiff