/* -*- 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. * * 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 2008 Sun Microsystems, Inc. All rights reserved * Use is subject to license terms. */ /* * 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 */ #ifndef AUTOCONF_INCLUDED #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DEBUG_SUBSYSTEM S_LLITE //#include #include #include "llite_internal.h" #include /** * 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 int cl_invalidatepage(struct page *vmpage, unsigned long offset) { struct inode *inode; struct lu_env *env; struct cl_page *page; struct cl_object *obj; int result; 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 */ result = 0; if (offset == 0) { 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); result = 1; lu_ref_del(&page->cp_reference, "delete", vmpage); cl_page_put(env, page); } } else LASSERT(vmpage->private == 0); cl_env_put(env, &refcheck); } } return result; } #ifdef HAVE_INVALIDATEPAGE_RETURN_INT static int ll_invalidatepage(struct page *page, unsigned long offset) { return cl_invalidatepage(page, offset); } #else /* !HAVE_INVALIDATEPAGE_RETURN_INT */ static void ll_invalidatepage(struct page *page, unsigned long offset) { cl_invalidatepage(page, offset); } #endif #ifdef HAVE_RELEASEPAGE_WITH_INT #define RELEASEPAGE_ARG_TYPE int #else #define RELEASEPAGE_ARG_TYPE gfp_t #endif static int ll_releasepage(struct page *page, RELEASEPAGE_ARG_TYPE gfp_mask) { void *cookie; cookie = cl_env_reenter(); ll_invalidatepage(page, 0); cl_env_reexit(cookie); return 1; } 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 + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT; *max_pages -= user_addr >> CFS_PAGE_SHIFT; OBD_ALLOC_WAIT(*pages, *max_pages * sizeof(**pages)); if (*pages) { down_read(¤t->mm->mmap_sem); result = get_user_pages(current, current->mm, user_addr, *max_pages, (rw == READ), 0, *pages, NULL); up_read(¤t->mm->mmap_sem); if (unlikely(result <= 0)) OBD_FREE(*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(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 ccc_page *clup; struct cl_2queue *queue; struct cl_object *obj = io->ci_obj; struct cl_sync_io *anchor = &ccc_env_info(env)->cti_sync_io; int i; ssize_t rc = 0; loff_t file_offset = pv->ldp_start_offset; size_t size = pv->ldp_size; int page_count = pv->ldp_nr; struct page **pages = pv->ldp_pages; size_t page_size = cl_page_size(obj); ENTRY; cl_sync_io_init(anchor, page_count); 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; } /* check the page type: if the page is a host page, then do * write directly */ /* * Very rare case that the host pages can be found for * directIO case, since linux kernel truncated all covered * pages before getting here. So, to make the OST happy(to * write a contiguous region), all pages are issued * here. -jay */ if (clp->cp_type == CPT_CACHEABLE) { cfs_page_t *vmpage = cl_page_vmpage(env, clp); cfs_page_t *src_page; cfs_page_t *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, KM_USER0); dst = kmap_atomic(dst_page, KM_USER1); memcpy(dst, (const void *)src, min(page_size, size)); kunmap_atomic(dst, KM_USER1); kunmap_atomic(src, KM_USER0); /* 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 direct-io read finds up-to-date page in the * cache, just copy it to the user space. Page will be * filtered out by vvp_page_prep_read(). This * preserves an invariant, that page is read at most * once, see cl_page_flags::CPF_READ_COMPLETED. */ } rc = cl_page_own(env, io, clp); if (rc) { LASSERT(clp->cp_state == CPS_FREEING); cl_page_put(env, clp); break; } clup = cl2ccc_page(cl_page_at(clp, &vvp_device_type)); clup->cpg_sync_io = anchor; cl_2queue_add(queue, clp); /* drop the reference count for cl_page_find, so that the page * will be freed in cl_2queue_fini. */ cl_page_put(env, 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)); size -= page_size; file_offset += page_size; } if (rc == 0) { rc = cl_io_submit_rw(env, io, rw == READ ? CRT_READ : CRT_WRITE, queue, CRP_NORMAL); if (rc == 0) { /* * If some pages weren't sent for any reason (e.g., * direct-io read found up-to-date pages in the * cache), count them as completed to avoid infinite * wait. */ cl_page_list_for_each(clp, &queue->c2_qin) cl_sync_io_note(anchor, +1); /* wait for the IO to be finished. */ rc = cl_sync_io_wait(env, io, &queue->c2_qout, anchor) ?: 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); } /* This is the maximum size of a single O_DIRECT request, based on a 128kB * 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. This is 22MB for 4kB pages. */ #define MAX_DIO_SIZE ((128 * 1024 / sizeof(struct brw_page) * CFS_PAGE_SIZE) & \ ~(PTLRPC_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); ssize_t count = iov_length(iov, nr_segs); ssize_t tot_bytes = 0, result = 0; struct ll_inode_info *lli = ll_i2info(inode); struct lov_stripe_md *lsm = lli->lli_smd; unsigned long seg = 0; size_t size = MAX_DIO_SIZE; int refcheck; ENTRY; if (!lli->lli_smd || !lli->lli_smd->lsm_object_id) 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="LPSZ" (max %lu), " "offset=%lld=%llx, pages "LPSZ" (max %lu)\n", inode->i_ino, inode->i_generation, inode, count, MAX_DIO_SIZE, file_offset, file_offset, count >> CFS_PAGE_SHIFT, MAX_DIO_SIZE >> CFS_PAGE_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 sem to operate transient pages. */ if (rw == READ) LOCK_INODE_MUTEX(inode); LASSERT(obj->cob_transient_pages == 0); for (seg = 0; seg < nr_segs; seg++) { size_t iov_left = iov[seg].iov_len; unsigned long user_addr = (unsigned long)iov[seg].iov_base; if (rw == READ) { if (file_offset >= inode->i_size) break; if (file_offset + iov_left > inode->i_size) iov_left = inode->i_size - file_offset; } while (iov_left > 0) { struct page **pages; int page_count, max_pages = 0; size_t 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 << CFS_PAGE_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 > (CFS_PAGE_SIZE / sizeof(*pages)) * CFS_PAGE_SIZE) { size = ((((size / 2) - 1) | ~CFS_PAGE_MASK) + 1) & CFS_PAGE_MASK; CDEBUG(D_VFSTRACE, "DIO size now %u\n", (int)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) UNLOCK_INODE_MUTEX(inode); if (tot_bytes > 0) { if (rw == WRITE) { lov_stripe_lock(lsm); obd_adjust_kms(ll_i2dtexp(inode), lsm, file_offset, 0); lov_stripe_unlock(lsm); } } cl_env_put(env, &refcheck); RETURN(tot_bytes ? : result); } struct address_space_operations ll_aops = { .readpage = ll_readpage, // .readpages = ll_readpages, .direct_IO = ll_direct_IO_26, .writepage = ll_writepage, .writepages = generic_writepages, .set_page_dirty = ll_set_page_dirty, .sync_page = NULL, .prepare_write = ll_prepare_write, .commit_write = ll_commit_write, .invalidatepage = ll_invalidatepage, .releasepage = (void *)ll_releasepage, .bmap = NULL };