-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
+/*
+ * GPL HEADER START
*
- * Copyright (c) 2001-2003 Cluster File Systems, Inc.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
- * This file is part of Lustre, http://www.lustre.org.
+ * 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.
*
- * Lustre is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License 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).
*
- * Lustre 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 for more details.
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see
+ * http://www.gnu.org/licenses/gpl-2.0.html
*
- * You should have received a copy of the GNU General Public License
- * along with Lustre; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2016, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
*/
-#include <linux/config.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/string.h>
-#include <linux/stat.h>
#include <linux/errno.h>
-#include <linux/smp_lock.h>
-#include <linux/unistd.h>
-#include <linux/version.h>
-#include <asm/system.h>
-#include <asm/uaccess.h>
-
-#include <linux/fs.h>
-#include <linux/stat.h>
-#include <asm/uaccess.h>
-#include <asm/segment.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
#include <linux/mm.h>
-#include <linux/pagemap.h>
-#include <linux/smp_lock.h>
-#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
-#include <linux/iobuf.h>
-#endif
#define DEBUG_SUBSYSTEM S_LLITE
-#include <linux/lustre_mds.h>
-#include <linux/lustre_lite.h>
#include "llite_internal.h"
-#include <linux/lustre_compat25.h>
+#include <lustre_compat.h>
+static const struct vm_operations_struct ll_file_vm_ops;
-struct ll_lock_tree_node {
- rb_node_t lt_node;
- struct list_head lt_locked_item;
- __u64 lt_oid;
- ldlm_policy_data_t lt_policy;
- struct lustre_handle lt_lockh;
- ldlm_mode_t lt_mode;
-};
-
-__u64 lov_merge_size(struct lov_stripe_md *lsm, int kms);
-int lt_get_mmap_locks(struct ll_lock_tree *tree, struct inode *inode,
- unsigned long addr, size_t count);
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0))
-struct page *ll_nopage(struct vm_area_struct *vma, unsigned long address,
- int *type);
-#else
-struct page *ll_nopage(struct vm_area_struct *vma, unsigned long address,
- int unused);
-#endif
-
-struct ll_lock_tree_node * ll_node_from_inode(struct inode *inode, __u64 start,
- __u64 end, ldlm_mode_t mode)
+void policy_from_vma(union ldlm_policy_data *policy, struct vm_area_struct *vma,
+ unsigned long addr, size_t count)
{
- struct ll_lock_tree_node *node;
-
- OBD_ALLOC(node, sizeof(*node));
- if (node == NULL)
- RETURN(ERR_PTR(-ENOMEM));
-
- node->lt_oid = ll_i2info(inode)->lli_smd->lsm_object_id;
- node->lt_policy.l_extent.start = start;
- node->lt_policy.l_extent.end = end;
- memset(&node->lt_lockh, 0, sizeof(node->lt_lockh));
- INIT_LIST_HEAD(&node->lt_locked_item);
- node->lt_mode = mode;
-
- return node;
+ policy->l_extent.start = ((addr - vma->vm_start) & PAGE_MASK) +
+ (vma->vm_pgoff << PAGE_SHIFT);
+ policy->l_extent.end = (policy->l_extent.start + count - 1) |
+ ~PAGE_MASK;
}
-int lt_compare(struct ll_lock_tree_node *one, struct ll_lock_tree_node *two)
+struct vm_area_struct *our_vma(struct mm_struct *mm, unsigned long addr,
+ size_t count)
{
- if ( one->lt_oid < two->lt_oid)
- return -1;
- if ( one->lt_oid > two->lt_oid)
- return 1;
-
- if ( one->lt_policy.l_extent.end < two->lt_policy.l_extent.start )
- return -1;
- if ( one->lt_policy.l_extent.start > two->lt_policy.l_extent.end )
- return 1;
-
- return 0; /* they are the same object and overlap */
-}
-
-static void lt_merge(struct ll_lock_tree_node *dst,
- struct ll_lock_tree_node *src)
-{
- dst->lt_policy.l_extent.start = min(dst->lt_policy.l_extent.start,
- src->lt_policy.l_extent.start);
- dst->lt_policy.l_extent.end = max(dst->lt_policy.l_extent.end,
- src->lt_policy.l_extent.end);
-
- /* XXX could be a real call to the dlm to find superset modes */
- if (src->lt_mode == LCK_PW && dst->lt_mode != LCK_PW)
- dst->lt_mode = LCK_PW;
-}
-
-static void lt_insert(struct ll_lock_tree *tree,
- struct ll_lock_tree_node *node)
-{
- struct ll_lock_tree_node *walk;
- rb_node_t **p, *parent;
+ struct vm_area_struct *vma, *ret = NULL;
ENTRY;
-restart:
- p = &tree->lt_root.rb_node;
- parent = NULL;
- while (*p) {
- parent = *p;
- walk = rb_entry(parent, struct ll_lock_tree_node, lt_node);
- switch (lt_compare(node, walk)) {
- case -1:
- p = &(*p)->rb_left;
- break;
- case 1:
- p = &(*p)->rb_right;
- break;
- case 0:
- lt_merge(node, walk);
- rb_erase(&walk->lt_node, &tree->lt_root);
- OBD_FREE(walk, sizeof(*walk));
- goto restart;
- break;
- default:
- LBUG();
- break;
- }
- }
- rb_link_node(&node->lt_node, parent, p);
- rb_insert_color(&node->lt_node, &tree->lt_root);
- EXIT;
-}
+ /* mmap_sem must have been held by caller. */
+ LASSERT(!down_write_trylock(&mm->mmap_sem));
-static struct ll_lock_tree_node *lt_least_node(struct ll_lock_tree *tree)
-{
- rb_node_t *rbnode;
- struct ll_lock_tree_node *node = NULL;
-
- for ( rbnode = tree->lt_root.rb_node; rbnode != NULL;
- rbnode = rbnode->rb_left) {
- if (rbnode->rb_left == NULL) {
- node = rb_entry(rbnode, struct ll_lock_tree_node,
- lt_node);
+ for(vma = find_vma(mm, addr);
+ vma != NULL && vma->vm_start < (addr + count); vma = vma->vm_next) {
+ if (vma->vm_ops && vma->vm_ops == &ll_file_vm_ops &&
+ vma->vm_flags & VM_SHARED) {
+ ret = vma;
break;
}
}
- RETURN(node);
+ RETURN(ret);
}
-int ll_tree_unlock(struct ll_lock_tree *tree, struct inode *inode)
+/**
+ * API independent part for page fault initialization.
+ * \param env - corespondent lu_env to processing
+ * \param vma - virtual memory area addressed to page fault
+ * \param index - page index corespondent to fault.
+ * \parm ra_flags - vma readahead flags.
+ *
+ * \return error codes from cl_io_init.
+ */
+static struct cl_io *
+ll_fault_io_init(struct lu_env *env, struct vm_area_struct *vma,
+ pgoff_t index, unsigned long *ra_flags)
{
- struct ll_lock_tree_node *node;
- struct list_head *pos, *n;
- int rc = 0;
- ENTRY;
+ struct file *file = vma->vm_file;
+ struct inode *inode = file_inode(file);
+ struct cl_io *io;
+ struct cl_fault_io *fio;
+ int rc;
+ ENTRY;
- list_for_each_safe(pos, n, &tree->lt_locked_list) {
- node = list_entry(pos, struct ll_lock_tree_node,
- lt_locked_item);
+ if (ll_file_nolock(file))
+ RETURN(ERR_PTR(-EOPNOTSUPP));
- rc = ll_extent_unlock(tree->lt_fd, inode,
- ll_i2info(inode)->lli_smd, node->lt_mode,
- &node->lt_lockh);
- if (rc != 0) {
- /* XXX better message */
- CERROR("couldn't unlock %d\n", rc);
- }
- list_del(&node->lt_locked_item);
- OBD_FREE(node, sizeof(*node));
- }
+restart:
+ io = vvp_env_thread_io(env);
+ io->ci_obj = ll_i2info(inode)->lli_clob;
+ LASSERT(io->ci_obj != NULL);
- while ((node = lt_least_node(tree))) {
- rb_erase(&node->lt_node, &tree->lt_root);
- OBD_FREE(node, sizeof(*node));
- }
+ fio = &io->u.ci_fault;
+ fio->ft_index = index;
+ fio->ft_executable = vma->vm_flags&VM_EXEC;
- RETURN(rc);
-}
-int ll_tree_lock(struct ll_lock_tree *tree,
- struct ll_lock_tree_node *first_node, struct inode *inode,
- const char *buf, size_t count, int ast_flags)
-{
- struct ll_lock_tree_node *node;
- int rc = 0;
- ENTRY;
+ /*
+ * disable VM_SEQ_READ and use VM_RAND_READ to make sure that
+ * the kernel will not read other pages not covered by ldlm in
+ * filemap_nopage. we do our readahead in ll_readpage.
+ */
+ if (ra_flags != NULL)
+ *ra_flags = vma->vm_flags & (VM_RAND_READ|VM_SEQ_READ);
+ vma->vm_flags &= ~VM_SEQ_READ;
+ vma->vm_flags |= VM_RAND_READ;
- tree->lt_root.rb_node = NULL;
- INIT_LIST_HEAD(&tree->lt_locked_list);
- if (first_node != NULL)
- lt_insert(tree, first_node);
+ CDEBUG(D_MMAP, "vm_flags: %lx (%lu %d)\n", vma->vm_flags,
+ fio->ft_index, fio->ft_executable);
- if (mapping_mapped(inode->i_mapping)) {
- rc = lt_get_mmap_locks(tree, inode, (unsigned long)buf, count);
- if (rc)
- GOTO(out, rc);
- }
+ rc = cl_io_init(env, io, CIT_FAULT, io->ci_obj);
+ if (rc == 0) {
+ struct vvp_io *vio = vvp_env_io(env);
+ struct ll_file_data *fd = LUSTRE_FPRIVATE(file);
- while ((node = lt_least_node(tree))) {
- struct obd_service_time *stime;
- stime = (node->lt_mode & LCK_PW) ?
- &ll_i2sbi(inode)->ll_write_stime :
- &ll_i2sbi(inode)->ll_read_stime;
-
- rc = ll_extent_lock(tree->lt_fd, inode,
- ll_i2info(inode)->lli_smd, node->lt_mode,
- &node->lt_policy, &node->lt_lockh,
- ast_flags, stime);
- if (rc != 0)
- GOTO(out, rc);
-
- rb_erase(&node->lt_node, &tree->lt_root);
- list_add_tail(&node->lt_locked_item, &tree->lt_locked_list);
- }
- RETURN(rc);
-out:
- ll_tree_unlock(tree, inode);
- RETURN(rc);
-}
+ LASSERT(vio->vui_cl.cis_io == io);
-static ldlm_mode_t mode_from_vma(struct vm_area_struct *vma)
-{
- /* we only want to hold PW locks if the mmap() can generate
- * writes back to the file and that only happens in shared
- * writable vmas */
- if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE))
- return LCK_PW;
- return LCK_PR;
-}
+ /* mmap lock must be MANDATORY it has to cache
+ * pages. */
+ io->ci_lockreq = CILR_MANDATORY;
+ vio->vui_fd = fd;
+ } else {
+ LASSERT(rc < 0);
+ cl_io_fini(env, io);
+ if (io->ci_need_restart)
+ goto restart;
-static void policy_from_vma(ldlm_policy_data_t *policy,
- struct vm_area_struct *vma, unsigned long addr,
- size_t count)
-{
- policy->l_extent.start = ((addr - vma->vm_start) & PAGE_CACHE_MASK) +
- (vma->vm_pgoff << PAGE_CACHE_SHIFT);
- policy->l_extent.end = (policy->l_extent.start + count - 1) |
- (PAGE_CACHE_SIZE - 1);
-}
-static struct vm_area_struct * our_vma(unsigned long addr, size_t count)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma, *ret = NULL;
- ENTRY;
+ io = ERR_PTR(rc);
+ }
- spin_lock(&mm->page_table_lock);
- for(vma = find_vma(mm, addr);
- vma != NULL && vma->vm_start < (addr + count); vma = vma->vm_next) {
- if (vma->vm_ops && vma->vm_ops->nopage == ll_nopage) {
- ret = vma;
- break;
- }
- }
- spin_unlock(&mm->page_table_lock);
- RETURN(ret);
+ RETURN(io);
}
-int lt_get_mmap_locks(struct ll_lock_tree *tree, struct inode *inode,
- unsigned long addr, size_t count)
+/* Sharing code of page_mkwrite method for rhel5 and rhel6 */
+static int ll_page_mkwrite0(struct vm_area_struct *vma, struct page *vmpage,
+ bool *retry)
{
- struct vm_area_struct *vma;
- struct ll_lock_tree_node *node;
- ldlm_policy_data_t policy;
- ENTRY;
-
- if (count == 0)
- RETURN(0);
-
- /* we need to look up vmas on page aligned addresses */
- count += addr & (PAGE_SIZE - 1);
- addr -= addr & (PAGE_SIZE - 1);
-
- while ((vma = our_vma(addr, count)) != NULL) {
-
- policy_from_vma(&policy, vma, addr, count);
- node = ll_node_from_inode(inode, policy.l_extent.start,
- policy.l_extent.end,
- mode_from_vma(vma));
- if (IS_ERR(node)) {
- CERROR("not enough mem for lock_tree_node!\n");
- RETURN(-ENOMEM);
+ struct lu_env *env;
+ struct cl_io *io;
+ struct vvp_io *vio;
+ int result;
+ __u16 refcheck;
+ sigset_t set;
+ struct inode *inode = NULL;
+ struct ll_inode_info *lli;
+ ENTRY;
+
+ LASSERT(vmpage != NULL);
+ env = cl_env_get(&refcheck);
+ if (IS_ERR(env))
+ RETURN(PTR_ERR(env));
+
+ io = ll_fault_io_init(env, vma, vmpage->index, NULL);
+ if (IS_ERR(io))
+ GOTO(out, result = PTR_ERR(io));
+
+ result = io->ci_result;
+ if (result < 0)
+ GOTO(out_io, result);
+
+ io->u.ci_fault.ft_mkwrite = 1;
+ io->u.ci_fault.ft_writable = 1;
+
+ vio = vvp_env_io(env);
+ vio->u.fault.ft_vma = vma;
+ vio->u.fault.ft_vmpage = vmpage;
+
+ set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM));
+
+ inode = vvp_object_inode(io->ci_obj);
+ lli = ll_i2info(inode);
+
+ result = cl_io_loop(env, io);
+
+ cfs_restore_sigs(set);
+
+ if (result == 0) {
+ lock_page(vmpage);
+ if (vmpage->mapping == NULL) {
+ unlock_page(vmpage);
+
+ /* page was truncated and lock was cancelled, return
+ * ENODATA so that VM_FAULT_NOPAGE will be returned
+ * to handle_mm_fault(). */
+ if (result == 0)
+ result = -ENODATA;
+ } else if (!PageDirty(vmpage)) {
+ /* race, the page has been cleaned by ptlrpcd after
+ * it was unlocked, it has to be added into dirty
+ * cache again otherwise this soon-to-dirty page won't
+ * consume any grants, even worse if this page is being
+ * transferred because it will break RPC checksum.
+ */
+ unlock_page(vmpage);
+
+ CDEBUG(D_MMAP, "Race on page_mkwrite %p/%lu, page has "
+ "been written out, retry.\n",
+ vmpage, vmpage->index);
+
+ *retry = true;
+ result = -EAGAIN;
}
- lt_insert(tree, node);
- if (vma->vm_end - addr >= count)
- break;
- count -= vma->vm_end - addr;
- addr = vma->vm_end;
+ if (result == 0)
+ ll_file_set_flag(lli, LLIF_DATA_MODIFIED);
}
- RETURN(0);
+ EXIT;
+
+out_io:
+ cl_io_fini(env, io);
+out:
+ cl_env_put(env, &refcheck);
+ CDEBUG(D_MMAP, "%s mkwrite with %d\n", current->comm, result);
+ LASSERT(ergo(result == 0, PageLocked(vmpage)));
+
+ /* if page has been unmapped, presumably due to lock reclaim for
+ * concurrent usage, add some delay before retrying to prevent
+ * entering live-lock situation with competitors
+ */
+ if (result == -ENODATA && inode != NULL) {
+ CDEBUG(D_MMAP, "delaying new page-fault for inode %p to "
+ "prevent live-lock\n", inode);
+ msleep(10);
+ }
+
+ return result;
+}
+
+static inline int to_fault_error(int result)
+{
+ switch(result) {
+ case 0:
+ result = VM_FAULT_LOCKED;
+ break;
+ case -ENOMEM:
+ result = VM_FAULT_OOM;
+ break;
+ default:
+ result = VM_FAULT_SIGBUS;
+ break;
+ }
+ return result;
}
-/* FIXME: there is a pagefault race goes as follow:
- * 1. A user process on node A accesses a portion of a mapped file,
- * resulting in a page fault. The pagefault handler invokes the
- * ll_nopage function, which reads the page into memory.
- * 2. A user process on node B writes to the same portion of the file
- * (either via mmap or write()), that cause node A to cancel the
- * lock and truncate the page.
- * 3. Node A then executes the rest of do_no_page(), entering the
- * now-invalid page into the PTEs.
+
+/**
+ * Lustre implementation of a vm_operations_struct::fault() method, called by
+ * VM to server page fault (both in kernel and user space).
*
- * Make the whole do_no_page as a hook to cover both the page cache
- * and page mapping installing with dlm lock would eliminate this race.
+ * \param vma - is virtiual area struct related to page fault
+ * \param vmf - structure which describe type and address where hit fault
+ *
+ * \return allocated and filled _locked_ page for address
+ * \retval VM_FAULT_ERROR on general error
+ * \retval NOPAGE_OOM not have memory for allocate new page
*/
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0))
-struct page *ll_nopage(struct vm_area_struct *vma, unsigned long address,
- int *type)
-#else
-struct page *ll_nopage(struct vm_area_struct *vma, unsigned long address,
- int unused)
-#endif
+static vm_fault_t ll_fault0(struct vm_area_struct *vma, struct vm_fault *vmf)
{
- struct file *filp = vma->vm_file;
- struct ll_file_data *fd = filp->private_data;
- struct inode *inode = filp->f_dentry->d_inode;
- struct lustre_handle lockh = { 0 };
- ldlm_policy_data_t policy;
- ldlm_mode_t mode;
- struct page *page;
- struct obd_service_time *stime;
- __u64 kms;
- unsigned long pgoff, size, rand_read, seq_read;
- int rc = 0;
- ENTRY;
-
- if (ll_i2info(inode)->lli_smd == NULL) {
- CERROR("No lsm on fault?\n");
- RETURN(NULL);
+ struct lu_env *env;
+ struct cl_io *io;
+ struct vvp_io *vio = NULL;
+ struct page *vmpage;
+ unsigned long ra_flags;
+ int result = 0;
+ int fault_ret = 0;
+ __u16 refcheck;
+ ENTRY;
+
+ env = cl_env_get(&refcheck);
+ if (IS_ERR(env))
+ RETURN(PTR_ERR(env));
+
+ if (ll_sbi_has_fast_read(ll_i2sbi(file_inode(vma->vm_file)))) {
+ /* do fast fault */
+ ll_cl_add(vma->vm_file, env, NULL, LCC_MMAP);
+ fault_ret = ll_filemap_fault(vma, vmf);
+ ll_cl_remove(vma->vm_file, env);
+
+ /* - If there is no error, then the page was found in cache and
+ * uptodate;
+ * - If VM_FAULT_RETRY is set, the page existed but failed to
+ * lock. It will return to kernel and retry;
+ * - Otherwise, it should try normal fault under DLM lock. */
+ if ((fault_ret & VM_FAULT_RETRY) ||
+ !(fault_ret & VM_FAULT_ERROR))
+ GOTO(out, result = 0);
+
+ fault_ret = 0;
+ }
+
+ io = ll_fault_io_init(env, vma, vmf->pgoff, &ra_flags);
+ if (IS_ERR(io))
+ GOTO(out, result = PTR_ERR(io));
+
+ result = io->ci_result;
+ if (result == 0) {
+ vio = vvp_env_io(env);
+ vio->u.fault.ft_vma = vma;
+ vio->u.fault.ft_vmpage = NULL;
+ vio->u.fault.ft_vmf = vmf;
+ vio->u.fault.ft_flags = 0;
+ vio->u.fault.ft_flags_valid = 0;
+
+ /* May call ll_readpage() */
+ ll_cl_add(vma->vm_file, env, io, LCC_MMAP);
+
+ result = cl_io_loop(env, io);
+
+ ll_cl_remove(vma->vm_file, env);
+
+ /* ft_flags are only valid if we reached
+ * the call to filemap_fault */
+ if (vio->u.fault.ft_flags_valid)
+ fault_ret = vio->u.fault.ft_flags;
+
+ vmpage = vio->u.fault.ft_vmpage;
+ if (result != 0 && vmpage != NULL) {
+ put_page(vmpage);
+ vmf->page = NULL;
+ }
}
+ cl_io_fini(env, io);
- /* start and end the lock on the first and last bytes in the page */
- policy_from_vma(&policy, vma, address, PAGE_CACHE_SIZE);
+ vma->vm_flags |= ra_flags;
- CDEBUG(D_MMAP, "nopage vma %p inode %lu, locking ["LPU64", "LPU64"]\n",
- vma, inode->i_ino, policy.l_extent.start,
- policy.l_extent.end);
+out:
+ cl_env_put(env, &refcheck);
+ if (result != 0 && !(fault_ret & VM_FAULT_RETRY))
+ fault_ret |= to_fault_error(result);
- mode = mode_from_vma(vma);
- stime = (mode & LCK_PW) ? &ll_i2sbi(inode)->ll_write_stime :
- &ll_i2sbi(inode)->ll_read_stime;
+ CDEBUG(D_MMAP, "%s fault %d/%d\n", current->comm, fault_ret, result);
+ RETURN(fault_ret);
+}
- rc = ll_extent_lock(fd, inode, ll_i2info(inode)->lli_smd, mode, &policy,
- &lockh, LDLM_FL_CBPENDING, stime);
- if (rc != 0)
- RETURN(NULL);
+#ifdef HAVE_VM_OPS_USE_VM_FAULT_ONLY
+static vm_fault_t ll_fault(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+#else
+static vm_fault_t ll_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+#endif
+ int count = 0;
+ bool printed = false;
+ bool cached;
+ vm_fault_t result;
+ ktime_t kstart = ktime_get();
+ sigset_t set;
+
+ result = pcc_fault(vma, vmf, &cached);
+ if (cached)
+ goto out;
+
+ /* Only SIGKILL and SIGTERM is allowed for fault/nopage/mkwrite
+ * so that it can be killed by admin but not cause segfault by
+ * other signals. */
+ set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM));
+
+ /* make sure offset is not a negative number */
+ if (vmf->pgoff > (MAX_LFS_FILESIZE >> PAGE_SHIFT))
+ return VM_FAULT_SIGBUS;
+restart:
+ result = ll_fault0(vma, vmf);
+ if (vmf->page &&
+ !(result & (VM_FAULT_RETRY | VM_FAULT_ERROR | VM_FAULT_LOCKED))) {
+ struct page *vmpage = vmf->page;
+
+ /* check if this page has been truncated */
+ lock_page(vmpage);
+ if (unlikely(vmpage->mapping == NULL)) { /* unlucky */
+ unlock_page(vmpage);
+ put_page(vmpage);
+ vmf->page = NULL;
+
+ if (!printed && ++count > 16) {
+ CWARN("the page is under heavy contention,"
+ "maybe your app(%s) needs revising :-)\n",
+ current->comm);
+ printed = true;
+ }
- /* XXX change inode size without i_sem hold! there is a race condition
- * with truncate path. (see ll_extent_lock) */
- kms = lov_merge_size(ll_i2info(inode)->lli_smd, 1);
- pgoff = ((address - vma->vm_start) >> PAGE_CACHE_SHIFT) + vma->vm_pgoff;
- size = (kms + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+ goto restart;
+ }
- if (pgoff >= size)
- ll_glimpse_size(inode);
- else
- inode->i_size = kms;
+ result |= VM_FAULT_LOCKED;
+ }
+ cfs_restore_sigs(set);
- /* disable VM_SEQ_READ and use VM_RAND_READ to make sure that
- * the kernel will not read other pages not covered by ldlm in
- * filemap_nopage. we do our readahead in ll_readpage.
- */
- rand_read = vma->vm_flags & VM_RAND_READ;
- seq_read = vma->vm_flags & VM_SEQ_READ;
- vma->vm_flags &= ~ VM_SEQ_READ;
- vma->vm_flags |= VM_RAND_READ;
+out:
+ if (vmf->page && result == VM_FAULT_LOCKED) {
+ ll_rw_stats_tally(ll_i2sbi(file_inode(vma->vm_file)),
+ current->pid, LUSTRE_FPRIVATE(vma->vm_file),
+ cl_offset(NULL, vmf->page->index), PAGE_SIZE,
+ READ);
+ ll_stats_ops_tally(ll_i2sbi(file_inode(vma->vm_file)),
+ LPROC_LL_FAULT,
+ ktime_us_delta(ktime_get(), kstart));
+ }
+
+ return result;
+}
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0))
- page = filemap_nopage(vma, address, type);
+#ifdef HAVE_VM_OPS_USE_VM_FAULT_ONLY
+static vm_fault_t ll_page_mkwrite(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
#else
- page = filemap_nopage(vma, address, unused);
+static vm_fault_t ll_page_mkwrite(struct vm_area_struct *vma,
+ struct vm_fault *vmf)
+{
#endif
- vma->vm_flags &= ~VM_RAND_READ;
- vma->vm_flags |= (rand_read | seq_read);
+ int count = 0;
+ bool printed = false;
+ bool retry;
+ bool cached;
+ ktime_t kstart = ktime_get();
+ vm_fault_t result;
+
+ result = pcc_page_mkwrite(vma, vmf, &cached);
+ if (cached)
+ goto out;
+
+ file_update_time(vma->vm_file);
+ do {
+ retry = false;
+ result = ll_page_mkwrite0(vma, vmf->page, &retry);
+
+ if (!printed && ++count > 16) {
+ const struct dentry *de = file_dentry(vma->vm_file);
+
+ CWARN("app(%s): the page %lu of file "DFID" is under"
+ " heavy contention\n",
+ current->comm, vmf->pgoff,
+ PFID(ll_inode2fid(de->d_inode)));
+ printed = true;
+ }
+ } while (retry);
+
+ switch(result) {
+ case 0:
+ LASSERT(PageLocked(vmf->page));
+ result = VM_FAULT_LOCKED;
+ break;
+ case -ENODATA:
+ case -EFAULT:
+ result = VM_FAULT_NOPAGE;
+ break;
+ case -ENOMEM:
+ result = VM_FAULT_OOM;
+ break;
+ case -EAGAIN:
+ result = VM_FAULT_RETRY;
+ break;
+ default:
+ result = VM_FAULT_SIGBUS;
+ break;
+ }
- ll_extent_unlock(fd, inode, ll_i2info(inode)->lli_smd, mode, &lockh);
- RETURN(page);
+out:
+ if (result == VM_FAULT_LOCKED) {
+ ll_rw_stats_tally(ll_i2sbi(file_inode(vma->vm_file)),
+ current->pid, LUSTRE_FPRIVATE(vma->vm_file),
+ cl_offset(NULL, vmf->page->index), PAGE_SIZE,
+ WRITE);
+ ll_stats_ops_tally(ll_i2sbi(file_inode(vma->vm_file)),
+ LPROC_LL_MKWRITE,
+ ktime_us_delta(ktime_get(), kstart));
+ }
+
+ return result;
}
-/* return the user space pointer that maps to a file offset via a vma */
-static inline unsigned long file_to_user(struct vm_area_struct *vma,
- __u64 byte)
+/**
+ * To avoid cancel the locks covering mmapped region for lock cache pressure,
+ * we track the mapped vma count in vvp_object::vob_mmap_cnt.
+ */
+static void ll_vm_open(struct vm_area_struct * vma)
{
- return vma->vm_start +
- (byte - ((__u64)vma->vm_pgoff << PAGE_CACHE_SHIFT));
-
+ struct inode *inode = file_inode(vma->vm_file);
+ struct vvp_object *vob = cl_inode2vvp(inode);
+
+ ENTRY;
+ LASSERT(atomic_read(&vob->vob_mmap_cnt) >= 0);
+ atomic_inc(&vob->vob_mmap_cnt);
+ pcc_vm_open(vma);
+ EXIT;
}
-#define VMA_DEBUG(vma, fmt, arg...) \
- CDEBUG(D_MMAP, "vma(%p) start(%ld) end(%ld) pgoff(%ld) inode(%p): " \
- fmt, vma, vma->vm_start, vma->vm_end, vma->vm_pgoff, \
- vma->vm_file->f_dentry->d_inode, ## arg);
-
-#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
-/* [first, last] are the byte offsets affected.
- * vm_{start, end} are user addresses of the first byte of the mapping and
- * the next byte beyond it
- * vm_pgoff is the page index of the first byte in the mapping */
-static void teardown_vmas(struct vm_area_struct *vma, __u64 first,
- __u64 last)
+/**
+ * Dual to ll_vm_open().
+ */
+static void ll_vm_close(struct vm_area_struct *vma)
{
- unsigned long address, len;
- for (; vma ; vma = vma->vm_next_share) {
- if (last >> PAGE_CACHE_SHIFT < vma->vm_pgoff)
- continue;
- if (first >> PAGE_CACHE_SHIFT > (vma->vm_pgoff +
- ((vma->vm_end - vma->vm_start) >> PAGE_CACHE_SHIFT)))
- continue;
-
- address = max((unsigned long)vma->vm_start,
- file_to_user(vma, first));
- len = min((unsigned long)vma->vm_end,
- file_to_user(vma, last) + 1) - address;
-
- VMA_DEBUG(vma, "zapping vma [address=%ld len=%ld]\n",
- address, len);
- LASSERT(vma->vm_mm);
- ll_zap_page_range(vma, address, len);
- }
+ struct inode *inode = file_inode(vma->vm_file);
+ struct vvp_object *vob = cl_inode2vvp(inode);
+
+ ENTRY;
+ atomic_dec(&vob->vob_mmap_cnt);
+ LASSERT(atomic_read(&vob->vob_mmap_cnt) >= 0);
+ pcc_vm_close(vma);
+ EXIT;
}
-#endif
/* XXX put nice comment here. talk about __free_pte -> dirty pages and
* nopage's reference passing to the pte */
-int ll_teardown_mmaps(struct address_space *mapping, __u64 first,
- __u64 last)
+int ll_teardown_mmaps(struct address_space *mapping, __u64 first, __u64 last)
{
int rc = -ENOENT;
ENTRY;
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0))
+ LASSERTF(last > first, "last %llu first %llu\n", last, first);
if (mapping_mapped(mapping)) {
rc = 0;
- unmap_mapping_range(mapping, first + PAGE_SIZE - 1,
- last - first + 1, 1);
- }
-#else
- spin_lock(&mapping->i_shared_lock);
- if (mapping->i_mmap != NULL) {
- rc = 0;
- teardown_vmas(mapping->i_mmap, first, last);
+ unmap_mapping_range(mapping, first + PAGE_SIZE - 1,
+ last - first + 1, 1);
}
- if (mapping->i_mmap_shared != NULL) {
- rc = 0;
- teardown_vmas(mapping->i_mmap_shared, first, last);
- }
- spin_unlock(&mapping->i_shared_lock);
-#endif
RETURN(rc);
}
-static struct vm_operations_struct ll_file_vm_ops = {
- .nopage = ll_nopage,
+static const struct vm_operations_struct ll_file_vm_ops = {
+ .fault = ll_fault,
+ .page_mkwrite = ll_page_mkwrite,
+ .open = ll_vm_open,
+ .close = ll_vm_close,
};
-int ll_file_mmap(struct file * file, struct vm_area_struct * vma)
+int ll_file_mmap(struct file *file, struct vm_area_struct * vma)
{
- int rc;
- ENTRY;
-
- rc = generic_file_mmap(file, vma);
- if (rc == 0)
- vma->vm_ops = &ll_file_vm_ops;
-
- RETURN(rc);
+ struct inode *inode = file_inode(file);
+ ktime_t kstart = ktime_get();
+ bool cached;
+ int rc;
+
+ ENTRY;
+
+ if (ll_file_nolock(file))
+ RETURN(-EOPNOTSUPP);
+
+ rc = pcc_file_mmap(file, vma, &cached);
+ if (cached && rc != 0)
+ RETURN(rc);
+
+ rc = generic_file_mmap(file, vma);
+ if (rc == 0) {
+ vma->vm_ops = &ll_file_vm_ops;
+ vma->vm_ops->open(vma);
+ /* update the inode's size and mtime */
+ if (!cached)
+ rc = ll_glimpse_size(inode);
+ }
+
+ if (!rc)
+ ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_MMAP,
+ ktime_us_delta(ktime_get(), kstart));
+
+ RETURN(rc);
}
-
git://git.whamcloud.com / fs / lustre-release.git / blobdiff