X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fllite%2Fllite_mmap.c;h=bc4104222e5b0c1fd236e4ac3db0cbf6e6a75ec1;hp=f17a90d74b62b5d1185ddd081b4500a1f5d36bc1;hb=4a8f90cfdf8868d25f14b02214e51e7423d70160;hpb=997572f6c8c3ea5f5c829810d342ee76d7437f7c diff --git a/lustre/llite/llite_mmap.c b/lustre/llite/llite_mmap.c index f17a90d..bc41042 100644 --- a/lustre/llite/llite_mmap.c +++ b/lustre/llite/llite_mmap.c @@ -1,6 +1,4 @@ -/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- - * vim:expandtab:shiftwidth=8:tabstop=8: - * +/* * GPL HEADER START * * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. @@ -26,26 +24,23 @@ * GPL HEADER END */ /* - * Copyright 2008 Sun Microsystems, Inc. All rights reserved + * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. + * + * Copyright (c) 2011, 2014, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ * Lustre is a trademark of Sun Microsystems, Inc. */ -#ifndef AUTOCONF_INCLUDED -#include -#endif #include #include #include #include #include -#include #include #include -#include #include #include @@ -53,482 +48,419 @@ #include #include #include -#include #define DEBUG_SUBSYSTEM S_LLITE -//#include -#include #include "llite_internal.h" -#include - -#define VMA_DEBUG(vma, fmt, arg...) \ - CDEBUG(D_MMAP, "vma(%p) start(%ld) end(%ld) pgoff(%ld) inode(%p) " \ - "ino(%lu) iname(%s): " fmt, vma, vma->vm_start, vma->vm_end, \ - vma->vm_pgoff, vma->vm_file->f_dentry->d_inode, \ - vma->vm_file->f_dentry->d_inode->i_ino, \ - vma->vm_file->f_dentry->d_iname, ## arg); \ - - -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; - struct inode *lt_inode; -}; - -int lt_get_mmap_locks(struct ll_lock_tree *tree, - unsigned long addr, size_t count); - -struct page *ll_nopage(struct vm_area_struct *vma, unsigned long address, - int *type); - -struct ll_lock_tree_node * ll_node_from_inode(struct inode *inode, __u64 start, - __u64 end, ldlm_mode_t mode) -{ - struct ll_lock_tree_node *node; +#include - OBD_ALLOC(node, sizeof(*node)); - if (node == NULL) - RETURN(ERR_PTR(-ENOMEM)); - - node->lt_inode = inode; - 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; -} - -int lt_compare(struct ll_lock_tree_node *one, struct ll_lock_tree_node *two) -{ - /* To avoid multiple fs deadlock */ - if (one->lt_inode->i_sb->s_dev < two->lt_inode->i_sb->s_dev) - return -1; - if (one->lt_inode->i_sb->s_dev > two->lt_inode->i_sb->s_dev) - return 1; - - 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; - 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; -} +static const struct vm_operations_struct ll_file_vm_ops; -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); - break; - } - } - RETURN(node); -} - -int ll_tree_unlock(struct ll_lock_tree *tree) -{ - struct ll_lock_tree_node *node; - struct list_head *pos, *n; - struct inode *inode; - int rc = 0; - ENTRY; - - list_for_each_safe(pos, n, &tree->lt_locked_list) { - node = list_entry(pos, struct ll_lock_tree_node, - lt_locked_item); - - inode = node->lt_inode; - 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)); - } - - while ((node = lt_least_node(tree))) { - rb_erase(&node->lt_node, &tree->lt_root); - OBD_FREE(node, sizeof(*node)); - } - - RETURN(rc); -} - -int ll_tree_lock(struct ll_lock_tree *tree, - struct ll_lock_tree_node *first_node, - const char *buf, size_t count, int ast_flags) -{ - struct ll_lock_tree_node *node; - int rc = 0; - ENTRY; - - tree->lt_root.rb_node = NULL; - INIT_LIST_HEAD(&tree->lt_locked_list); - if (first_node != NULL) - lt_insert(tree, first_node); - - /* To avoid such subtle deadlock case: client1 try to read file1 to - * mmapped file2, on the same time, client2 try to read file2 to - * mmapped file1.*/ - rc = lt_get_mmap_locks(tree, (unsigned long)buf, count); - if (rc) - GOTO(out, rc); - - while ((node = lt_least_node(tree))) { - struct inode *inode = node->lt_inode; - rc = ll_extent_lock(tree->lt_fd, inode, - ll_i2info(inode)->lli_smd, node->lt_mode, - &node->lt_policy, &node->lt_lockh, - ast_flags); - 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); - RETURN(rc); -} - -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; -} - -static void policy_from_vma(ldlm_policy_data_t *policy, +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) & CFS_PAGE_MASK) + - (vma->vm_pgoff << CFS_PAGE_SHIFT); + policy->l_extent.start = ((addr - vma->vm_start) & PAGE_MASK) + + (vma->vm_pgoff << PAGE_CACHE_SHIFT); policy->l_extent.end = (policy->l_extent.start + count - 1) | - ~CFS_PAGE_MASK; + ~PAGE_MASK; } -static struct vm_area_struct * our_vma(unsigned long addr, size_t count) +struct vm_area_struct *our_vma(struct mm_struct *mm, unsigned long addr, + size_t count) { - struct mm_struct *mm = current->mm; struct vm_area_struct *vma, *ret = NULL; ENTRY; - /* No MM (e.g. NFS)? No vmas too. */ - if (!mm) - RETURN(NULL); + /* mmap_sem must have been held by caller. */ + LASSERT(!down_write_trylock(&mm->mmap_sem)); - 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 && + if (vma->vm_ops && vma->vm_ops == &ll_file_vm_ops && vma->vm_flags & VM_SHARED) { ret = vma; break; } } - spin_unlock(&mm->page_table_lock); RETURN(ret); } -int ll_region_mapped(unsigned long addr, size_t count) +/** + * API independent part for page fault initialization. + * \param vma - virtual memory area addressed to page fault + * \param env - corespondent lu_env to processing + * \param nest - nested level + * \param index - page index corespondent to fault. + * \parm ra_flags - vma readahead flags. + * + * \return allocated and initialized env for fault operation. + * \retval EINVAL if env can't allocated + * \return other error codes from cl_io_init. + */ +static struct cl_io * +ll_fault_io_init(struct vm_area_struct *vma, struct lu_env **env_ret, + struct cl_env_nest *nest, pgoff_t index, + unsigned long *ra_flags) { - return !!our_vma(addr, count); -} + struct file *file = vma->vm_file; + struct inode *inode = file->f_path.dentry->d_inode; + struct cl_io *io; + struct cl_fault_io *fio; + struct lu_env *env; + int rc; + ENTRY; + + *env_ret = NULL; + if (ll_file_nolock(file)) + RETURN(ERR_PTR(-EOPNOTSUPP)); + + /* + * page fault can be called when lustre IO is + * already active for the current thread, e.g., when doing read/write + * against user level buffer mapped from Lustre buffer. To avoid + * stomping on existing context, optionally force an allocation of a new + * one. + */ + env = cl_env_nested_get(nest); + if (IS_ERR(env)) + RETURN(ERR_PTR(-EINVAL)); -int lt_get_mmap_locks(struct ll_lock_tree *tree, - unsigned long addr, size_t count) -{ - struct vm_area_struct *vma; - struct ll_lock_tree_node *node; - ldlm_policy_data_t policy; - struct inode *inode; - ENTRY; + *env_ret = env; + + io = vvp_env_thread_io(env); + io->ci_obj = ll_i2info(inode)->lli_clob; + LASSERT(io->ci_obj != NULL); + + fio = &io->u.ci_fault; + fio->ft_index = index; + fio->ft_executable = vma->vm_flags&VM_EXEC; + + /* + * 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; + + CDEBUG(D_MMAP, "vm_flags: %lx (%lu %d)\n", vma->vm_flags, + fio->ft_index, fio->ft_executable); + + 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); - if (count == 0) - RETURN(0); + LASSERT(vio->vui_cl.cis_io == io); - /* we need to look up vmas on page aligned addresses */ - count += addr & (~CFS_PAGE_MASK); - addr &= CFS_PAGE_MASK; + /* 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); + cl_env_nested_put(nest, env); + io = ERR_PTR(rc); + } - while ((vma = our_vma(addr, count)) != NULL) { - LASSERT(vma->vm_file); + return io; +} - inode = vma->vm_file->f_dentry->d_inode; - 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); +/* 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 lu_env *env; + struct cl_io *io; + struct vvp_io *vio; + struct cl_env_nest nest; + int result; + sigset_t set; + struct inode *inode; + struct ll_inode_info *lli; + ENTRY; + + LASSERT(vmpage != NULL); + + io = ll_fault_io_init(vma, &env, &nest, 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)); + + /* we grab lli_trunc_sem to exclude truncate case. + * Otherwise, we could add dirty pages into osc cache + * while truncate is on-going. */ + inode = vvp_object_inode(io->ci_obj); + lli = ll_i2info(inode); + down_read(&lli->lli_trunc_sem); + + result = cl_io_loop(env, io); + + up_read(&lli->lli_trunc_sem); + + 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) { + spin_lock(&lli->lli_lock); + lli->lli_flags |= LLIF_DATA_MODIFIED; + spin_unlock(&lli->lli_lock); + } } - RETURN(0); + EXIT; + +out_io: + cl_io_fini(env, io); + cl_env_nested_put(&nest, env); +out: + CDEBUG(D_MMAP, "%s mkwrite with %d\n", current->comm, result); + LASSERT(ergo(result == 0, PageLocked(vmpage))); + + return result; +} + +static inline int to_fault_error(int result) +{ + switch(result) { + case 0: + result = VM_FAULT_LOCKED; + break; + case -EFAULT: + result = VM_FAULT_NOPAGE; + break; + case -ENOMEM: + result = VM_FAULT_OOM; + break; + default: + result = VM_FAULT_SIGBUS; + break; + } + return result; } /** - * Page fault handler. + * Lustre implementation of a vm_operations_struct::fault() method, called by + * VM to server page fault (both in kernel and user space). * * \param vma - is virtiual area struct related to page fault - * \param address - address when hit fault - * \param type - of fault + * \param vmf - structure which describe type and address where hit fault * - * \return allocated and filled page for address - * \retval NOPAGE_SIGBUS if page not exist on this address + * \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 */ -struct page *ll_nopage(struct vm_area_struct *vma, unsigned long address, - int *type) +static int ll_fault0(struct vm_area_struct *vma, struct vm_fault *vmf) { - struct file *filp = vma->vm_file; - struct ll_file_data *fd = LUSTRE_FPRIVATE(filp); - 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 = NULL; - struct ll_inode_info *lli = ll_i2info(inode); - struct lov_stripe_md *lsm; - struct ost_lvb lvb; - __u64 kms, old_mtime; - unsigned long pgoff, size, rand_read, seq_read; - int rc = 0; + struct lu_env *env; + struct cl_io *io; + struct vvp_io *vio = NULL; + struct page *vmpage; + unsigned long ra_flags; + struct cl_env_nest nest; + int result; + int fault_ret = 0; ENTRY; - if (lli->lli_smd == NULL) { - CERROR("No lsm on fault?\n"); - RETURN(NULL); - } + io = ll_fault_io_init(vma, &env, &nest, vmf->pgoff, &ra_flags); + if (IS_ERR(io)) + RETURN(to_fault_error(PTR_ERR(io))); - ll_clear_file_contended(inode); - - /* start and end the lock on the first and last bytes in the page */ - policy_from_vma(&policy, vma, address, CFS_PAGE_SIZE); - - CDEBUG(D_MMAP, "nopage vma %p inode %lu, locking ["LPU64", "LPU64"]\n", - vma, inode->i_ino, policy.l_extent.start, policy.l_extent.end); - - mode = mode_from_vma(vma); - old_mtime = LTIME_S(inode->i_mtime); - - lsm = lli->lli_smd; - rc = ll_extent_lock(fd, inode, lsm, mode, &policy, - &lockh, LDLM_FL_CBPENDING); - if (rc != 0) - RETURN(NULL); - - if (vma->vm_flags & VM_EXEC && LTIME_S(inode->i_mtime) != old_mtime) - CWARN("binary changed. inode %lu\n", inode->i_ino); - - lov_stripe_lock(lsm); - inode_init_lvb(inode, &lvb); - obd_merge_lvb(ll_i2dtexp(inode), lsm, &lvb, 1); - kms = lvb.lvb_size; - - pgoff = ((address - vma->vm_start) >> CFS_PAGE_SHIFT) + vma->vm_pgoff; - size = (kms + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT; - - if (pgoff >= size) { - lov_stripe_unlock(lsm); - ll_glimpse_size(inode, LDLM_FL_BLOCK_GRANTED); - } else { - /* XXX change inode size without ll_inode_size_lock() held! - * there is a race condition with truncate path. (see - * ll_extent_lock) */ - /* XXX i_size_write() is not used because it is not safe to - * take the ll_inode_size_lock() due to a potential lock - * inversion (bug 6077). And since it's not safe to use - * i_size_write() without a covering mutex we do the - * assignment directly. It is not critical that the - * size be correct. */ - /* region is within kms and, hence, within real file size (A). - * We need to increase i_size to cover the read region so that - * generic_file_read() will do its job, but that doesn't mean - * the kms size is _correct_, it is only the _minimum_ size. - * If someone does a stat they will get the correct size which - * will always be >= the kms value here. b=11081 */ - if (i_size_read(inode) < kms) { - inode->i_size = kms; - CDEBUG(D_INODE, "ino=%lu, updating i_size %llu\n", - inode->i_ino, i_size_read(inode)); - } - lov_stripe_unlock(lsm); - } - - /* If mapping is writeable, adjust kms to cover this page, - * but do not extend kms beyond actual file size. - * policy.l_extent.end is set to the end of the page by policy_from_vma - * bug 10919 */ - lov_stripe_lock(lsm); - if (mode == LCK_PW) - obd_adjust_kms(ll_i2dtexp(inode), lsm, - min_t(loff_t, policy.l_extent.end + 1, - i_size_read(inode)), 0); - lov_stripe_unlock(lsm); - - /* 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; + 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; - page = filemap_nopage(vma, address, type); - if (page != NOPAGE_SIGBUS && page != NOPAGE_OOM) - LL_CDEBUG_PAGE(D_PAGE, page, "got addr %lu type %lx\n", address, - (long)type); - else - CDEBUG(D_PAGE, "got addr %lu type %lx - SIGBUS\n", address, - (long)type); + /* May call ll_readpage() */ + ll_cl_add(vma->vm_file, env, io); - vma->vm_flags &= ~VM_RAND_READ; - vma->vm_flags |= (rand_read | seq_read); + result = cl_io_loop(env, io); - ll_extent_unlock(fd, inode, ll_i2info(inode)->lli_smd, mode, &lockh); - RETURN(page); -} + ll_cl_remove(vma->vm_file, env); -/* To avoid cancel the locks covering mmapped region for lock cache pressure, - * we track the mapped vma count by lli_mmap_cnt. - * ll_vm_open(): when first vma is linked, split locks from lru. - * ll_vm_close(): when last vma is unlinked, join all this file's locks to lru. - * - * XXX we don't check the if the region of vma/lock for performance. - */ -static void ll_vm_open(struct vm_area_struct * vma) -{ - struct inode *inode = vma->vm_file->f_dentry->d_inode; - struct ll_inode_info *lli = ll_i2info(inode); - ENTRY; + /* 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; - LASSERT(vma->vm_file); + vmpage = vio->u.fault.ft_vmpage; + if (result != 0 && vmpage != NULL) { + page_cache_release(vmpage); + vmf->page = NULL; + } + } + cl_io_fini(env, io); + cl_env_nested_put(&nest, env); - spin_lock(&lli->lli_lock); - LASSERT(atomic_read(&lli->lli_mmap_cnt) >= 0); + vma->vm_flags |= ra_flags; + if (result != 0 && !(fault_ret & VM_FAULT_RETRY)) + fault_ret |= to_fault_error(result); - atomic_inc(&lli->lli_mmap_cnt); - spin_unlock(&lli->lli_lock); + CDEBUG(D_MMAP, "%s fault %d/%d\n", + current->comm, fault_ret, result); + RETURN(fault_ret); } -static void ll_vm_close(struct vm_area_struct *vma) +static int ll_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { - struct inode *inode = vma->vm_file->f_dentry->d_inode; - struct ll_inode_info *lli = ll_i2info(inode); - ENTRY; + int count = 0; + bool printed = false; + int result; + sigset_t set; - LASSERT(vma->vm_file); + /* 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)); - spin_lock(&lli->lli_lock); - LASSERT(atomic_read(&lli->lli_mmap_cnt) > 0); +restart: + result = ll_fault0(vma, vmf); + LASSERT(!(result & VM_FAULT_LOCKED)); + if (result == 0) { + struct page *vmpage = vmf->page; + + /* check if this page has been truncated */ + lock_page(vmpage); + if (unlikely(vmpage->mapping == NULL)) { /* unlucky */ + unlock_page(vmpage); + page_cache_release(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; + } + + goto restart; + } - atomic_dec(&lli->lli_mmap_cnt); - spin_unlock(&lli->lli_lock); + result |= VM_FAULT_LOCKED; + } + cfs_restore_sigs(set); + return result; } -#ifndef HAVE_FILEMAP_POPULATE -static int (*filemap_populate)(struct vm_area_struct * area, unsigned long address, unsigned long len, pgprot_t prot, unsigned long pgoff, int nonblock); -#endif -static int ll_populate(struct vm_area_struct *area, unsigned long address, - unsigned long len, pgprot_t prot, unsigned long pgoff, - int nonblock) +static int ll_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) { - int rc = 0; - ENTRY; + int count = 0; + bool printed = false; + bool retry; + int result; + + do { + retry = false; + result = ll_page_mkwrite0(vma, vmf->page, &retry); + + if (!printed && ++count > 16) { + const struct dentry *de = vma->vm_file->f_path.dentry; + + 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; + } - /* always set nonblock as true to avoid page read ahead */ - rc = filemap_populate(area, address, len, prot, pgoff, 1); - RETURN(rc); + 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 << CFS_PAGE_SHIFT)); + struct inode *inode = vma->vm_file->f_path.dentry->d_inode; + struct vvp_object *vob = cl_inode2vvp(inode); + + ENTRY; + LASSERT(vma->vm_file); + LASSERT(atomic_read(&vob->vob_mmap_cnt) >= 0); + atomic_inc(&vob->vob_mmap_cnt); + EXIT; +} +/** + * Dual to ll_vm_open(). + */ +static void ll_vm_close(struct vm_area_struct *vma) +{ + struct inode *inode = vma->vm_file->f_path.dentry->d_inode; + struct vvp_object *vob = cl_inode2vvp(inode); + + ENTRY; + LASSERT(vma->vm_file); + atomic_dec(&vob->vob_mmap_cnt); + LASSERT(atomic_read(&vob->vob_mmap_cnt) >= 0); + EXIT; } /* XXX put nice comment here. talk about __free_pte -> dirty pages and @@ -541,36 +473,36 @@ int ll_teardown_mmaps(struct address_space *mapping, __u64 first, __u64 last) LASSERTF(last > first, "last "LPU64" first "LPU64"\n", last, first); if (mapping_mapped(mapping)) { rc = 0; - unmap_mapping_range(mapping, first + CFS_PAGE_SIZE - 1, + unmap_mapping_range(mapping, first + PAGE_CACHE_SIZE - 1, last - first + 1, 0); } RETURN(rc); } -static struct vm_operations_struct ll_file_vm_ops = { - .nopage = ll_nopage, - .open = ll_vm_open, - .close = ll_vm_close, - .populate = ll_populate, +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) { + struct inode *inode = file->f_path.dentry->d_inode; int rc; ENTRY; - ll_stats_ops_tally(ll_i2sbi(file->f_dentry->d_inode), LPROC_LL_MAP, 1); + if (ll_file_nolock(file)) + RETURN(-EOPNOTSUPP); + + ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_MAP, 1); rc = generic_file_mmap(file, vma); if (rc == 0) { -#if !defined(HAVE_FILEMAP_POPULATE) - if (!filemap_populate) - filemap_populate = vma->vm_ops->populate; -#endif vma->vm_ops = &ll_file_vm_ops; vma->vm_ops->open(vma); /* update the inode's size and mtime */ - rc = ll_glimpse_size(file->f_dentry->d_inode, 0); + rc = ll_glimpse_size(inode); } RETURN(rc);