From ccd979bdbce9fba8412beb3f1de68a9d0171b12c Mon Sep 17 00:00:00 2001 From: Mark Fasheh Date: Thu, 15 Dec 2005 14:31:24 -0800 Subject: [PATCH] OCFS2: The Second Oracle Cluster Filesystem The OCFS2 file system module. Signed-off-by: Mark Fasheh Signed-off-by: Kurt Hackel --- fs/ocfs2/aops.c | 643 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 643 insertions(+) create mode 100644 fs/ocfs2/aops.c (limited to 'fs/ocfs2/aops.c') diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c new file mode 100644 index 000000000000..8f4467a930a5 --- /dev/null +++ b/fs/ocfs2/aops.c @@ -0,0 +1,643 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * Copyright (C) 2002, 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * 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 for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include +#include +#include +#include +#include + +#define MLOG_MASK_PREFIX ML_FILE_IO +#include + +#include "ocfs2.h" + +#include "alloc.h" +#include "aops.h" +#include "dlmglue.h" +#include "extent_map.h" +#include "file.h" +#include "inode.h" +#include "journal.h" +#include "super.h" +#include "symlink.h" + +#include "buffer_head_io.h" + +static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, + struct buffer_head *bh_result, int create) +{ + int err = -EIO; + int status; + struct ocfs2_dinode *fe = NULL; + struct buffer_head *bh = NULL; + struct buffer_head *buffer_cache_bh = NULL; + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + void *kaddr; + + mlog_entry("(0x%p, %llu, 0x%p, %d)\n", inode, + (unsigned long long)iblock, bh_result, create); + + BUG_ON(ocfs2_inode_is_fast_symlink(inode)); + + if ((iblock << inode->i_sb->s_blocksize_bits) > PATH_MAX + 1) { + mlog(ML_ERROR, "block offset > PATH_MAX: %llu", + (unsigned long long)iblock); + goto bail; + } + + status = ocfs2_read_block(OCFS2_SB(inode->i_sb), + OCFS2_I(inode)->ip_blkno, + &bh, OCFS2_BH_CACHED, inode); + if (status < 0) { + mlog_errno(status); + goto bail; + } + fe = (struct ocfs2_dinode *) bh->b_data; + + if (!OCFS2_IS_VALID_DINODE(fe)) { + mlog(ML_ERROR, "Invalid dinode #%"MLFu64": signature = %.*s\n", + fe->i_blkno, 7, fe->i_signature); + goto bail; + } + + if ((u64)iblock >= ocfs2_clusters_to_blocks(inode->i_sb, + le32_to_cpu(fe->i_clusters))) { + mlog(ML_ERROR, "block offset is outside the allocated size: " + "%llu\n", (unsigned long long)iblock); + goto bail; + } + + /* We don't use the page cache to create symlink data, so if + * need be, copy it over from the buffer cache. */ + if (!buffer_uptodate(bh_result) && ocfs2_inode_is_new(inode)) { + u64 blkno = le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) + + iblock; + buffer_cache_bh = sb_getblk(osb->sb, blkno); + if (!buffer_cache_bh) { + mlog(ML_ERROR, "couldn't getblock for symlink!\n"); + goto bail; + } + + /* we haven't locked out transactions, so a commit + * could've happened. Since we've got a reference on + * the bh, even if it commits while we're doing the + * copy, the data is still good. */ + if (buffer_jbd(buffer_cache_bh) + && ocfs2_inode_is_new(inode)) { + kaddr = kmap_atomic(bh_result->b_page, KM_USER0); + if (!kaddr) { + mlog(ML_ERROR, "couldn't kmap!\n"); + goto bail; + } + memcpy(kaddr + (bh_result->b_size * iblock), + buffer_cache_bh->b_data, + bh_result->b_size); + kunmap_atomic(kaddr, KM_USER0); + set_buffer_uptodate(bh_result); + } + brelse(buffer_cache_bh); + } + + map_bh(bh_result, inode->i_sb, + le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) + iblock); + + err = 0; + +bail: + if (bh) + brelse(bh); + + mlog_exit(err); + return err; +} + +static int ocfs2_get_block(struct inode *inode, sector_t iblock, + struct buffer_head *bh_result, int create) +{ + int err = 0; + u64 p_blkno, past_eof; + + mlog_entry("(0x%p, %llu, 0x%p, %d)\n", inode, + (unsigned long long)iblock, bh_result, create); + + if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE) + mlog(ML_NOTICE, "get_block on system inode 0x%p (%lu)\n", + inode, inode->i_ino); + + if (S_ISLNK(inode->i_mode)) { + /* this always does I/O for some reason. */ + err = ocfs2_symlink_get_block(inode, iblock, bh_result, create); + goto bail; + } + + /* this can happen if another node truncs after our extend! */ + spin_lock(&OCFS2_I(inode)->ip_lock); + if (iblock >= ocfs2_clusters_to_blocks(inode->i_sb, + OCFS2_I(inode)->ip_clusters)) + err = -EIO; + spin_unlock(&OCFS2_I(inode)->ip_lock); + if (err) + goto bail; + + err = ocfs2_extent_map_get_blocks(inode, iblock, 1, &p_blkno, + NULL); + if (err) { + mlog(ML_ERROR, "Error %d from get_blocks(0x%p, %llu, 1, " + "%"MLFu64", NULL)\n", err, inode, + (unsigned long long)iblock, p_blkno); + goto bail; + } + + map_bh(bh_result, inode->i_sb, p_blkno); + + if (bh_result->b_blocknr == 0) { + err = -EIO; + mlog(ML_ERROR, "iblock = %llu p_blkno = %"MLFu64" " + "blkno=(%"MLFu64")\n", (unsigned long long)iblock, + p_blkno, OCFS2_I(inode)->ip_blkno); + } + + past_eof = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode)); + mlog(0, "Inode %lu, past_eof = %"MLFu64"\n", inode->i_ino, past_eof); + + if (create && (iblock >= past_eof)) + set_buffer_new(bh_result); + +bail: + if (err < 0) + err = -EIO; + + mlog_exit(err); + return err; +} + +static int ocfs2_readpage(struct file *file, struct page *page) +{ + struct inode *inode = page->mapping->host; + loff_t start = (loff_t)page->index << PAGE_CACHE_SHIFT; + int ret, unlock = 1; + + mlog_entry("(0x%p, %lu)\n", file, (page ? page->index : 0)); + + ret = ocfs2_meta_lock_with_page(inode, NULL, NULL, 0, page); + if (ret != 0) { + if (ret == AOP_TRUNCATED_PAGE) + unlock = 0; + mlog_errno(ret); + goto out; + } + + down_read(&OCFS2_I(inode)->ip_alloc_sem); + + /* + * i_size might have just been updated as we grabed the meta lock. We + * might now be discovering a truncate that hit on another node. + * block_read_full_page->get_block freaks out if it is asked to read + * beyond the end of a file, so we check here. Callers + * (generic_file_read, fault->nopage) are clever enough to check i_size + * and notice that the page they just read isn't needed. + * + * XXX sys_readahead() seems to get that wrong? + */ + if (start >= i_size_read(inode)) { + char *addr = kmap(page); + memset(addr, 0, PAGE_SIZE); + flush_dcache_page(page); + kunmap(page); + SetPageUptodate(page); + ret = 0; + goto out_alloc; + } + + ret = ocfs2_data_lock_with_page(inode, 0, page); + if (ret != 0) { + if (ret == AOP_TRUNCATED_PAGE) + unlock = 0; + mlog_errno(ret); + goto out_alloc; + } + + ret = block_read_full_page(page, ocfs2_get_block); + unlock = 0; + + ocfs2_data_unlock(inode, 0); +out_alloc: + up_read(&OCFS2_I(inode)->ip_alloc_sem); + ocfs2_meta_unlock(inode, 0); +out: + if (unlock) + unlock_page(page); + mlog_exit(ret); + return ret; +} + +/* Note: Because we don't support holes, our allocation has + * already happened (allocation writes zeros to the file data) + * so we don't have to worry about ordered writes in + * ocfs2_writepage. + * + * ->writepage is called during the process of invalidating the page cache + * during blocked lock processing. It can't block on any cluster locks + * to during block mapping. It's relying on the fact that the block + * mapping can't have disappeared under the dirty pages that it is + * being asked to write back. + */ +static int ocfs2_writepage(struct page *page, struct writeback_control *wbc) +{ + int ret; + + mlog_entry("(0x%p)\n", page); + + ret = block_write_full_page(page, ocfs2_get_block, wbc); + + mlog_exit(ret); + + return ret; +} + +/* + * ocfs2_prepare_write() can be an outer-most ocfs2 call when it is called + * from loopback. It must be able to perform its own locking around + * ocfs2_get_block(). + */ +int ocfs2_prepare_write(struct file *file, struct page *page, + unsigned from, unsigned to) +{ + struct inode *inode = page->mapping->host; + int ret; + + mlog_entry("(0x%p, 0x%p, %u, %u)\n", file, page, from, to); + + ret = ocfs2_meta_lock_with_page(inode, NULL, NULL, 0, page); + if (ret != 0) { + mlog_errno(ret); + goto out; + } + + down_read(&OCFS2_I(inode)->ip_alloc_sem); + + ret = block_prepare_write(page, from, to, ocfs2_get_block); + + up_read(&OCFS2_I(inode)->ip_alloc_sem); + + ocfs2_meta_unlock(inode, 0); +out: + mlog_exit(ret); + return ret; +} + +/* Taken from ext3. We don't necessarily need the full blown + * functionality yet, but IMHO it's better to cut and paste the whole + * thing so we can avoid introducing our own bugs (and easily pick up + * their fixes when they happen) --Mark */ +static int walk_page_buffers( handle_t *handle, + struct buffer_head *head, + unsigned from, + unsigned to, + int *partial, + int (*fn)( handle_t *handle, + struct buffer_head *bh)) +{ + struct buffer_head *bh; + unsigned block_start, block_end; + unsigned blocksize = head->b_size; + int err, ret = 0; + struct buffer_head *next; + + for ( bh = head, block_start = 0; + ret == 0 && (bh != head || !block_start); + block_start = block_end, bh = next) + { + next = bh->b_this_page; + block_end = block_start + blocksize; + if (block_end <= from || block_start >= to) { + if (partial && !buffer_uptodate(bh)) + *partial = 1; + continue; + } + err = (*fn)(handle, bh); + if (!ret) + ret = err; + } + return ret; +} + +struct ocfs2_journal_handle *ocfs2_start_walk_page_trans(struct inode *inode, + struct page *page, + unsigned from, + unsigned to) +{ + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct ocfs2_journal_handle *handle = NULL; + int ret = 0; + + handle = ocfs2_start_trans(osb, NULL, OCFS2_INODE_UPDATE_CREDITS); + if (!handle) { + ret = -ENOMEM; + mlog_errno(ret); + goto out; + } + + if (ocfs2_should_order_data(inode)) { + ret = walk_page_buffers(handle->k_handle, + page_buffers(page), + from, to, NULL, + ocfs2_journal_dirty_data); + if (ret < 0) + mlog_errno(ret); + } +out: + if (ret) { + if (handle) + ocfs2_commit_trans(handle); + handle = ERR_PTR(ret); + } + return handle; +} + +static int ocfs2_commit_write(struct file *file, struct page *page, + unsigned from, unsigned to) +{ + int ret, extending = 0, locklevel = 0; + loff_t new_i_size; + struct buffer_head *di_bh = NULL; + struct inode *inode = page->mapping->host; + struct ocfs2_journal_handle *handle = NULL; + + mlog_entry("(0x%p, 0x%p, %u, %u)\n", file, page, from, to); + + /* NOTE: ocfs2_file_aio_write has ensured that it's safe for + * us to sample inode->i_size here without the metadata lock: + * + * 1) We're currently holding the inode alloc lock, so no + * nodes can change it underneath us. + * + * 2) We've had to take the metadata lock at least once + * already to check for extending writes, hence insuring + * that our current copy is also up to date. + */ + new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; + if (new_i_size > i_size_read(inode)) { + extending = 1; + locklevel = 1; + } + + ret = ocfs2_meta_lock_with_page(inode, NULL, &di_bh, locklevel, page); + if (ret != 0) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_data_lock_with_page(inode, 1, page); + if (ret != 0) { + mlog_errno(ret); + goto out_unlock_meta; + } + + if (extending) { + handle = ocfs2_start_walk_page_trans(inode, page, from, to); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + handle = NULL; + goto out_unlock_data; + } + + /* Mark our buffer early. We'd rather catch this error up here + * as opposed to after a successful commit_write which would + * require us to set back inode->i_size. */ + ret = ocfs2_journal_access(handle, inode, di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret < 0) { + mlog_errno(ret); + goto out_commit; + } + } + + /* might update i_size */ + ret = generic_commit_write(file, page, from, to); + if (ret < 0) { + mlog_errno(ret); + goto out_commit; + } + + if (extending) { + loff_t size = (u64) i_size_read(inode); + struct ocfs2_dinode *di = + (struct ocfs2_dinode *)di_bh->b_data; + + /* ocfs2_mark_inode_dirty is too heavy to use here. */ + inode->i_blocks = ocfs2_align_bytes_to_sectors(size); + inode->i_ctime = inode->i_mtime = CURRENT_TIME; + + di->i_size = cpu_to_le64(size); + di->i_ctime = di->i_mtime = + cpu_to_le64(inode->i_mtime.tv_sec); + di->i_ctime_nsec = di->i_mtime_nsec = + cpu_to_le32(inode->i_mtime.tv_nsec); + + ret = ocfs2_journal_dirty(handle, di_bh); + if (ret < 0) { + mlog_errno(ret); + goto out_commit; + } + } + + BUG_ON(extending && (i_size_read(inode) != new_i_size)); + +out_commit: + if (handle) + ocfs2_commit_trans(handle); +out_unlock_data: + ocfs2_data_unlock(inode, 1); +out_unlock_meta: + ocfs2_meta_unlock(inode, locklevel); +out: + if (di_bh) + brelse(di_bh); + + mlog_exit(ret); + return ret; +} + +static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block) +{ + sector_t status; + u64 p_blkno = 0; + int err = 0; + struct inode *inode = mapping->host; + + mlog_entry("(block = %llu)\n", (unsigned long long)block); + + /* We don't need to lock journal system files, since they aren't + * accessed concurrently from multiple nodes. + */ + if (!INODE_JOURNAL(inode)) { + err = ocfs2_meta_lock(inode, NULL, NULL, 0); + if (err) { + if (err != -ENOENT) + mlog_errno(err); + goto bail; + } + down_read(&OCFS2_I(inode)->ip_alloc_sem); + } + + err = ocfs2_extent_map_get_blocks(inode, block, 1, &p_blkno, + NULL); + + if (!INODE_JOURNAL(inode)) { + up_read(&OCFS2_I(inode)->ip_alloc_sem); + ocfs2_meta_unlock(inode, 0); + } + + if (err) { + mlog(ML_ERROR, "get_blocks() failed, block = %llu\n", + (unsigned long long)block); + mlog_errno(err); + goto bail; + } + + +bail: + status = err ? 0 : p_blkno; + + mlog_exit((int)status); + + return status; +} + +/* + * TODO: Make this into a generic get_blocks function. + * + * From do_direct_io in direct-io.c: + * "So what we do is to permit the ->get_blocks function to populate + * bh.b_size with the size of IO which is permitted at this offset and + * this i_blkbits." + * + * This function is called directly from get_more_blocks in direct-io.c. + * + * called like this: dio->get_blocks(dio->inode, fs_startblk, + * fs_count, map_bh, dio->rw == WRITE); + */ +static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock, + unsigned long max_blocks, + struct buffer_head *bh_result, int create) +{ + int ret; + u64 vbo_max; /* file offset, max_blocks from iblock */ + u64 p_blkno; + int contig_blocks; + unsigned char blocksize_bits; + + if (!inode || !bh_result) { + mlog(ML_ERROR, "inode or bh_result is null\n"); + return -EIO; + } + + blocksize_bits = inode->i_sb->s_blocksize_bits; + + /* This function won't even be called if the request isn't all + * nicely aligned and of the right size, so there's no need + * for us to check any of that. */ + + vbo_max = ((u64)iblock + max_blocks) << blocksize_bits; + + spin_lock(&OCFS2_I(inode)->ip_lock); + if ((iblock + max_blocks) > + ocfs2_clusters_to_blocks(inode->i_sb, + OCFS2_I(inode)->ip_clusters)) { + spin_unlock(&OCFS2_I(inode)->ip_lock); + ret = -EIO; + goto bail; + } + spin_unlock(&OCFS2_I(inode)->ip_lock); + + /* This figures out the size of the next contiguous block, and + * our logical offset */ + ret = ocfs2_extent_map_get_blocks(inode, iblock, 1, &p_blkno, + &contig_blocks); + if (ret) { + mlog(ML_ERROR, "get_blocks() failed iblock=%llu\n", + (unsigned long long)iblock); + ret = -EIO; + goto bail; + } + + map_bh(bh_result, inode->i_sb, p_blkno); + + /* make sure we don't map more than max_blocks blocks here as + that's all the kernel will handle at this point. */ + if (max_blocks < contig_blocks) + contig_blocks = max_blocks; + bh_result->b_size = contig_blocks << blocksize_bits; +bail: + return ret; +} + +/* + * ocfs2_dio_end_io is called by the dio core when a dio is finished. We're + * particularly interested in the aio/dio case. Like the core uses + * i_alloc_sem, we use the rw_lock DLM lock to protect io on one node from + * truncation on another. + */ +static void ocfs2_dio_end_io(struct kiocb *iocb, + loff_t offset, + ssize_t bytes, + void *private) +{ + struct inode *inode = iocb->ki_filp->f_dentry->d_inode; + + /* this io's submitter should not have unlocked this before we could */ + BUG_ON(!ocfs2_iocb_is_rw_locked(iocb)); + ocfs2_iocb_clear_rw_locked(iocb); + up_read(&inode->i_alloc_sem); + ocfs2_rw_unlock(inode, 0); +} + +static ssize_t ocfs2_direct_IO(int rw, + struct kiocb *iocb, + const struct iovec *iov, + loff_t offset, + unsigned long nr_segs) +{ + struct file *file = iocb->ki_filp; + struct inode *inode = file->f_dentry->d_inode->i_mapping->host; + int ret; + + mlog_entry_void(); + ret = blockdev_direct_IO_no_locking(rw, iocb, inode, + inode->i_sb->s_bdev, iov, offset, + nr_segs, + ocfs2_direct_IO_get_blocks, + ocfs2_dio_end_io); + mlog_exit(ret); + return ret; +} + +struct address_space_operations ocfs2_aops = { + .readpage = ocfs2_readpage, + .writepage = ocfs2_writepage, + .prepare_write = ocfs2_prepare_write, + .commit_write = ocfs2_commit_write, + .bmap = ocfs2_bmap, + .sync_page = block_sync_page, + .direct_IO = ocfs2_direct_IO +}; -- cgit v1.2.3-55-g7522