| /* -*- 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 <linux/fs.h> |
| #include <linux/slab.h> |
| #include <linux/highmem.h> |
| #include <linux/pagemap.h> |
| #include <asm/byteorder.h> |
| #include <linux/swap.h> |
| #include <linux/pipe_fs_i.h> |
| |
| #define MLOG_MASK_PREFIX ML_FILE_IO |
| #include <cluster/masklog.h> |
| |
| #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 "suballoc.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 #%llu: signature = %.*s\n", |
| (unsigned long long)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; |
| unsigned int ext_flags; |
| u64 p_blkno, past_eof; |
| struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); |
| |
| 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; |
| } |
| |
| err = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno, NULL, |
| &ext_flags); |
| if (err) { |
| mlog(ML_ERROR, "Error %d from get_blocks(0x%p, %llu, 1, " |
| "%llu, NULL)\n", err, inode, (unsigned long long)iblock, |
| (unsigned long long)p_blkno); |
| goto bail; |
| } |
| |
| /* |
| * ocfs2 never allocates in this function - the only time we |
| * need to use BH_New is when we're extending i_size on a file |
| * system which doesn't support holes, in which case BH_New |
| * allows block_prepare_write() to zero. |
| */ |
| mlog_bug_on_msg(create && p_blkno == 0 && ocfs2_sparse_alloc(osb), |
| "ino %lu, iblock %llu\n", inode->i_ino, |
| (unsigned long long)iblock); |
| |
| /* Treat the unwritten extent as a hole for zeroing purposes. */ |
| if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN)) |
| map_bh(bh_result, inode->i_sb, p_blkno); |
| |
| if (!ocfs2_sparse_alloc(osb)) { |
| if (p_blkno == 0) { |
| err = -EIO; |
| mlog(ML_ERROR, |
| "iblock = %llu p_blkno = %llu blkno=(%llu)\n", |
| (unsigned long long)iblock, |
| (unsigned long long)p_blkno, |
| (unsigned long long)OCFS2_I(inode)->ip_blkno); |
| mlog(ML_ERROR, "Size %llu, clusters %u\n", (unsigned long long)i_size_read(inode), OCFS2_I(inode)->ip_clusters); |
| dump_stack(); |
| } |
| |
| past_eof = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode)); |
| mlog(0, "Inode %lu, past_eof = %llu\n", inode->i_ino, |
| (unsigned long long)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, 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; |
| } |
| |
| /* |
| * This is called from ocfs2_write_zero_page() which has handled it's |
| * own cluster locking and has ensured allocation exists for those |
| * blocks to be written. |
| */ |
| int ocfs2_prepare_write_nolock(struct inode *inode, struct page *page, |
| unsigned from, unsigned to) |
| { |
| int ret; |
| |
| 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); |
| |
| 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 */ |
| 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; |
| } |
| |
| handle_t *ocfs2_start_walk_page_trans(struct inode *inode, |
| struct page *page, |
| unsigned from, |
| unsigned to) |
| { |
| struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); |
| handle_t *handle = NULL; |
| int ret = 0; |
| |
| handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS); |
| if (!handle) { |
| ret = -ENOMEM; |
| mlog_errno(ret); |
| goto out; |
| } |
| |
| if (ocfs2_should_order_data(inode)) { |
| ret = walk_page_buffers(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(osb, handle); |
| handle = ERR_PTR(ret); |
| } |
| return handle; |
| } |
| |
| 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, 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, &p_blkno, NULL, 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, |
| struct buffer_head *bh_result, int create) |
| { |
| int ret; |
| u64 p_blkno, inode_blocks; |
| int contig_blocks; |
| unsigned int ext_flags; |
| unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits; |
| unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits; |
| |
| /* 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. */ |
| |
| inode_blocks = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode)); |
| |
| /* |
| * Any write past EOF is not allowed because we'd be extending. |
| */ |
| if (create && (iblock + max_blocks) > inode_blocks) { |
| ret = -EIO; |
| goto bail; |
| } |
| |
| /* This figures out the size of the next contiguous block, and |
| * our logical offset */ |
| ret = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno, |
| &contig_blocks, &ext_flags); |
| if (ret) { |
| mlog(ML_ERROR, "get_blocks() failed iblock=%llu\n", |
| (unsigned long long)iblock); |
| ret = -EIO; |
| goto bail; |
| } |
| |
| if (!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)) && !p_blkno) { |
| ocfs2_error(inode->i_sb, |
| "Inode %llu has a hole at block %llu\n", |
| (unsigned long long)OCFS2_I(inode)->ip_blkno, |
| (unsigned long long)iblock); |
| ret = -EROFS; |
| goto bail; |
| } |
| |
| /* |
| * get_more_blocks() expects us to describe a hole by clearing |
| * the mapped bit on bh_result(). |
| * |
| * Consider an unwritten extent as a hole. |
| */ |
| if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN)) |
| map_bh(bh_result, inode->i_sb, p_blkno); |
| else { |
| /* |
| * ocfs2_prepare_inode_for_write() should have caught |
| * the case where we'd be filling a hole and triggered |
| * a buffered write instead. |
| */ |
| if (create) { |
| ret = -EIO; |
| mlog_errno(ret); |
| goto bail; |
| } |
| |
| clear_buffer_mapped(bh_result); |
| } |
| |
| /* 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_path.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); |
| } |
| |
| /* |
| * ocfs2_invalidatepage() and ocfs2_releasepage() are shamelessly stolen |
| * from ext3. PageChecked() bits have been removed as OCFS2 does not |
| * do journalled data. |
| */ |
| static void ocfs2_invalidatepage(struct page *page, unsigned long offset) |
| { |
| journal_t *journal = OCFS2_SB(page->mapping->host->i_sb)->journal->j_journal; |
| |
| journal_invalidatepage(journal, page, offset); |
| } |
| |
| static int ocfs2_releasepage(struct page *page, gfp_t wait) |
| { |
| journal_t *journal = OCFS2_SB(page->mapping->host->i_sb)->journal->j_journal; |
| |
| if (!page_has_buffers(page)) |
| return 0; |
| return journal_try_to_free_buffers(journal, page, wait); |
| } |
| |
| 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_path.dentry->d_inode->i_mapping->host; |
| int ret; |
| |
| mlog_entry_void(); |
| |
| if (!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))) { |
| /* |
| * We get PR data locks even for O_DIRECT. This |
| * allows concurrent O_DIRECT I/O but doesn't let |
| * O_DIRECT with extending and buffered zeroing writes |
| * race. If they did race then the buffered zeroing |
| * could be written back after the O_DIRECT I/O. It's |
| * one thing to tell people not to mix buffered and |
| * O_DIRECT writes, but expecting them to understand |
| * that file extension is also an implicit buffered |
| * write is too much. By getting the PR we force |
| * writeback of the buffered zeroing before |
| * proceeding. |
| */ |
| ret = ocfs2_data_lock(inode, 0); |
| if (ret < 0) { |
| mlog_errno(ret); |
| goto out; |
| } |
| ocfs2_data_unlock(inode, 0); |
| } |
| |
| 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); |
| out: |
| mlog_exit(ret); |
| return ret; |
| } |
| |
| static void ocfs2_figure_cluster_boundaries(struct ocfs2_super *osb, |
| u32 cpos, |
| unsigned int *start, |
| unsigned int *end) |
| { |
| unsigned int cluster_start = 0, cluster_end = PAGE_CACHE_SIZE; |
| |
| if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits)) { |
| unsigned int cpp; |
| |
| cpp = 1 << (PAGE_CACHE_SHIFT - osb->s_clustersize_bits); |
| |
| cluster_start = cpos % cpp; |
| cluster_start = cluster_start << osb->s_clustersize_bits; |
| |
| cluster_end = cluster_start + osb->s_clustersize; |
| } |
| |
| BUG_ON(cluster_start > PAGE_SIZE); |
| BUG_ON(cluster_end > PAGE_SIZE); |
| |
| if (start) |
| *start = cluster_start; |
| if (end) |
| *end = cluster_end; |
| } |
| |
| /* |
| * 'from' and 'to' are the region in the page to avoid zeroing. |
| * |
| * If pagesize > clustersize, this function will avoid zeroing outside |
| * of the cluster boundary. |
| * |
| * from == to == 0 is code for "zero the entire cluster region" |
| */ |
| static void ocfs2_clear_page_regions(struct page *page, |
| struct ocfs2_super *osb, u32 cpos, |
| unsigned from, unsigned to) |
| { |
| void *kaddr; |
| unsigned int cluster_start, cluster_end; |
| |
| ocfs2_figure_cluster_boundaries(osb, cpos, &cluster_start, &cluster_end); |
| |
| kaddr = kmap_atomic(page, KM_USER0); |
| |
| if (from || to) { |
| if (from > cluster_start) |
| memset(kaddr + cluster_start, 0, from - cluster_start); |
| if (to < cluster_end) |
| memset(kaddr + to, 0, cluster_end - to); |
| } else { |
| memset(kaddr + cluster_start, 0, cluster_end - cluster_start); |
| } |
| |
| kunmap_atomic(kaddr, KM_USER0); |
| } |
| |
| /* |
| * Some of this taken from block_prepare_write(). We already have our |
| * mapping by now though, and the entire write will be allocating or |
| * it won't, so not much need to use BH_New. |
| * |
| * This will also skip zeroing, which is handled externally. |
| */ |
| int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno, |
| struct inode *inode, unsigned int from, |
| unsigned int to, int new) |
| { |
| int ret = 0; |
| struct buffer_head *head, *bh, *wait[2], **wait_bh = wait; |
| unsigned int block_end, block_start; |
| unsigned int bsize = 1 << inode->i_blkbits; |
| |
| if (!page_has_buffers(page)) |
| create_empty_buffers(page, bsize, 0); |
| |
| head = page_buffers(page); |
| for (bh = head, block_start = 0; bh != head || !block_start; |
| bh = bh->b_this_page, block_start += bsize) { |
| block_end = block_start + bsize; |
| |
| /* |
| * Ignore blocks outside of our i/o range - |
| * they may belong to unallocated clusters. |
| */ |
| if (block_start >= to || block_end <= from) { |
| if (PageUptodate(page)) |
| set_buffer_uptodate(bh); |
| continue; |
| } |
| |
| /* |
| * For an allocating write with cluster size >= page |
| * size, we always write the entire page. |
| */ |
| |
| if (buffer_new(bh)) |
| clear_buffer_new(bh); |
| |
| if (!buffer_mapped(bh)) { |
| map_bh(bh, inode->i_sb, *p_blkno); |
| unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr); |
| } |
| |
| if (PageUptodate(page)) { |
| if (!buffer_uptodate(bh)) |
| set_buffer_uptodate(bh); |
| } else if (!buffer_uptodate(bh) && !buffer_delay(bh) && |
| (block_start < from || block_end > to)) { |
| ll_rw_block(READ, 1, &bh); |
| *wait_bh++=bh; |
| } |
| |
| *p_blkno = *p_blkno + 1; |
| } |
| |
| /* |
| * If we issued read requests - let them complete. |
| */ |
| while(wait_bh > wait) { |
| wait_on_buffer(*--wait_bh); |
| if (!buffer_uptodate(*wait_bh)) |
| ret = -EIO; |
| } |
| |
| if (ret == 0 || !new) |
| return ret; |
| |
| /* |
| * If we get -EIO above, zero out any newly allocated blocks |
| * to avoid exposing stale data. |
| */ |
| bh = head; |
| block_start = 0; |
| do { |
| void *kaddr; |
| |
| block_end = block_start + bsize; |
| if (block_end <= from) |
| goto next_bh; |
| if (block_start >= to) |
| break; |
| |
| kaddr = kmap_atomic(page, KM_USER0); |
| memset(kaddr+block_start, 0, bh->b_size); |
| flush_dcache_page(page); |
| kunmap_atomic(kaddr, KM_USER0); |
| set_buffer_uptodate(bh); |
| mark_buffer_dirty(bh); |
| |
| next_bh: |
| block_start = block_end; |
| bh = bh->b_this_page; |
| } while (bh != head); |
| |
| return ret; |
| } |
| |
| /* |
| * This will copy user data from the buffer page in the splice |
| * context. |
| * |
| * For now, we ignore SPLICE_F_MOVE as that would require some extra |
| * communication out all the way to ocfs2_write(). |
| */ |
| int ocfs2_map_and_write_splice_data(struct inode *inode, |
| struct ocfs2_write_ctxt *wc, u64 *p_blkno, |
| unsigned int *ret_from, unsigned int *ret_to) |
| { |
| int ret; |
| unsigned int to, from, cluster_start, cluster_end; |
| char *src, *dst; |
| struct ocfs2_splice_write_priv *sp = wc->w_private; |
| struct pipe_buffer *buf = sp->s_buf; |
| unsigned long bytes, src_from; |
| struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); |
| |
| ocfs2_figure_cluster_boundaries(osb, wc->w_cpos, &cluster_start, |
| &cluster_end); |
| |
| from = sp->s_offset; |
| src_from = sp->s_buf_offset; |
| bytes = wc->w_count; |
| |
| if (wc->w_large_pages) { |
| /* |
| * For cluster size < page size, we have to |
| * calculate pos within the cluster and obey |
| * the rightmost boundary. |
| */ |
| bytes = min(bytes, (unsigned long)(osb->s_clustersize |
| - (wc->w_pos & (osb->s_clustersize - 1)))); |
| } |
| to = from + bytes; |
| |
| if (wc->w_this_page_new) |
| ret = ocfs2_map_page_blocks(wc->w_this_page, p_blkno, inode, |
| cluster_start, cluster_end, 1); |
| else |
| ret = ocfs2_map_page_blocks(wc->w_this_page, p_blkno, inode, |
| from, to, 0); |
| if (ret) { |
| mlog_errno(ret); |
| goto out; |
| } |
| |
| BUG_ON(from > PAGE_CACHE_SIZE); |
| BUG_ON(to > PAGE_CACHE_SIZE); |
| BUG_ON(from > osb->s_clustersize); |
| BUG_ON(to > osb->s_clustersize); |
| |
| src = buf->ops->map(sp->s_pipe, buf, 1); |
| dst = kmap_atomic(wc->w_this_page, KM_USER1); |
| memcpy(dst + from, src + src_from, bytes); |
| kunmap_atomic(wc->w_this_page, KM_USER1); |
| buf->ops->unmap(sp->s_pipe, buf, src); |
| |
| wc->w_finished_copy = 1; |
| |
| *ret_from = from; |
| *ret_to = to; |
| out: |
| |
| return bytes ? (unsigned int)bytes : ret; |
| } |
| |
| /* |
| * This will copy user data from the iovec in the buffered write |
| * context. |
| */ |
| int ocfs2_map_and_write_user_data(struct inode *inode, |
| struct ocfs2_write_ctxt *wc, u64 *p_blkno, |
| unsigned int *ret_from, unsigned int *ret_to) |
| { |
| int ret; |
| unsigned int to, from, cluster_start, cluster_end; |
| unsigned long bytes, src_from; |
| char *dst; |
| struct ocfs2_buffered_write_priv *bp = wc->w_private; |
| const struct iovec *cur_iov = bp->b_cur_iov; |
| char __user *buf; |
| struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); |
| |
| ocfs2_figure_cluster_boundaries(osb, wc->w_cpos, &cluster_start, |
| &cluster_end); |
| |
| buf = cur_iov->iov_base + bp->b_cur_off; |
| src_from = (unsigned long)buf & ~PAGE_CACHE_MASK; |
| |
| from = wc->w_pos & (PAGE_CACHE_SIZE - 1); |
| |
| /* |
| * This is a lot of comparisons, but it reads quite |
| * easily, which is important here. |
| */ |
| /* Stay within the src page */ |
| bytes = PAGE_SIZE - src_from; |
| /* Stay within the vector */ |
| bytes = min(bytes, |
| (unsigned long)(cur_iov->iov_len - bp->b_cur_off)); |
| /* Stay within count */ |
| bytes = min(bytes, (unsigned long)wc->w_count); |
| /* |
| * For clustersize > page size, just stay within |
| * target page, otherwise we have to calculate pos |
| * within the cluster and obey the rightmost |
| * boundary. |
| */ |
| if (wc->w_large_pages) { |
| /* |
| * For cluster size < page size, we have to |
| * calculate pos within the cluster and obey |
| * the rightmost boundary. |
| */ |
| bytes = min(bytes, (unsigned long)(osb->s_clustersize |
| - (wc->w_pos & (osb->s_clustersize - 1)))); |
| } else { |
| /* |
| * cluster size > page size is the most common |
| * case - we just stay within the target page |
| * boundary. |
| */ |
| bytes = min(bytes, PAGE_CACHE_SIZE - from); |
| } |
| |
| to = from + bytes; |
| |
| if (wc->w_this_page_new) |
| ret = ocfs2_map_page_blocks(wc->w_this_page, p_blkno, inode, |
| cluster_start, cluster_end, 1); |
| else |
| ret = ocfs2_map_page_blocks(wc->w_this_page, p_blkno, inode, |
| from, to, 0); |
| if (ret) { |
| mlog_errno(ret); |
| goto out; |
| } |
| |
| BUG_ON(from > PAGE_CACHE_SIZE); |
| BUG_ON(to > PAGE_CACHE_SIZE); |
| BUG_ON(from > osb->s_clustersize); |
| BUG_ON(to > osb->s_clustersize); |
| |
| dst = kmap(wc->w_this_page); |
| memcpy(dst + from, bp->b_src_buf + src_from, bytes); |
| kunmap(wc->w_this_page); |
| |
| /* |
| * XXX: This is slow, but simple. The caller of |
| * ocfs2_buffered_write_cluster() is responsible for |
| * passing through the iovecs, so it's difficult to |
| * predict what our next step is in here after our |
| * initial write. A future version should be pushing |
| * that iovec manipulation further down. |
| * |
| * By setting this, we indicate that a copy from user |
| * data was done, and subsequent calls for this |
| * cluster will skip copying more data. |
| */ |
| wc->w_finished_copy = 1; |
| |
| *ret_from = from; |
| *ret_to = to; |
| out: |
| |
| return bytes ? (unsigned int)bytes : ret; |
| } |
| |
| /* |
| * Map, fill and write a page to disk. |
| * |
| * The work of copying data is done via callback. Newly allocated |
| * pages which don't take user data will be zero'd (set 'new' to |
| * indicate an allocating write) |
| * |
| * Returns a negative error code or the number of bytes copied into |
| * the page. |
| */ |
| int ocfs2_write_data_page(struct inode *inode, handle_t *handle, |
| u64 *p_blkno, struct page *page, |
| struct ocfs2_write_ctxt *wc, int new) |
| { |
| int ret, copied = 0; |
| unsigned int from = 0, to = 0; |
| unsigned int cluster_start, cluster_end; |
| unsigned int zero_from = 0, zero_to = 0; |
| |
| ocfs2_figure_cluster_boundaries(OCFS2_SB(inode->i_sb), wc->w_cpos, |
| &cluster_start, &cluster_end); |
| |
| if ((wc->w_pos >> PAGE_CACHE_SHIFT) == page->index |
| && !wc->w_finished_copy) { |
| |
| wc->w_this_page = page; |
| wc->w_this_page_new = new; |
| ret = wc->w_write_data_page(inode, wc, p_blkno, &from, &to); |
| if (ret < 0) { |
| mlog_errno(ret); |
| goto out; |
| } |
| |
| copied = ret; |
| |
| zero_from = from; |
| zero_to = to; |
| if (new) { |
| from = cluster_start; |
| to = cluster_end; |
| } |
| } else { |
| /* |
| * If we haven't allocated the new page yet, we |
| * shouldn't be writing it out without copying user |
| * data. This is likely a math error from the caller. |
| */ |
| BUG_ON(!new); |
| |
| from = cluster_start; |
| to = cluster_end; |
| |
| ret = ocfs2_map_page_blocks(page, p_blkno, inode, |
| cluster_start, cluster_end, 1); |
| if (ret) { |
| mlog_errno(ret); |
| goto out; |
| } |
| } |
| |
| /* |
| * Parts of newly allocated pages need to be zero'd. |
| * |
| * Above, we have also rewritten 'to' and 'from' - as far as |
| * the rest of the function is concerned, the entire cluster |
| * range inside of a page needs to be written. |
| * |
| * We can skip this if the page is up to date - it's already |
| * been zero'd from being read in as a hole. |
| */ |
| if (new && !PageUptodate(page)) |
| ocfs2_clear_page_regions(page, OCFS2_SB(inode->i_sb), |
| wc->w_cpos, zero_from, zero_to); |
| |
| flush_dcache_page(page); |
| |
| if (ocfs2_should_order_data(inode)) { |
| ret = walk_page_buffers(handle, |
| page_buffers(page), |
| from, to, NULL, |
| ocfs2_journal_dirty_data); |
| if (ret < 0) |
| mlog_errno(ret); |
| } |
| |
| /* |
| * We don't use generic_commit_write() because we need to |
| * handle our own i_size update. |
| */ |
| ret = block_commit_write(page, from, to); |
| if (ret) |
| mlog_errno(ret); |
| out: |
| |
| return copied ? copied : ret; |
| } |
| |
| /* |
| * Do the actual write of some data into an inode. Optionally allocate |
| * in order to fulfill the write. |
| * |
| * cpos is the logical cluster offset within the file to write at |
| * |
| * 'phys' is the physical mapping of that offset. a 'phys' value of |
| * zero indicates that allocation is required. In this case, data_ac |
| * and meta_ac should be valid (meta_ac can be null if metadata |
| * allocation isn't required). |
| */ |
| static ssize_t ocfs2_write(struct file *file, u32 phys, handle_t *handle, |
| struct buffer_head *di_bh, |
| struct ocfs2_alloc_context *data_ac, |
| struct ocfs2_alloc_context *meta_ac, |
| struct ocfs2_write_ctxt *wc) |
| { |
| int ret, i, numpages = 1, new; |
| unsigned int copied = 0; |
| u32 tmp_pos; |
| u64 v_blkno, p_blkno; |
| struct address_space *mapping = file->f_mapping; |
| struct inode *inode = mapping->host; |
| unsigned long index, start; |
| struct page **cpages; |
| |
| new = phys == 0 ? 1 : 0; |
| |
| /* |
| * Figure out how many pages we'll be manipulating here. For |
| * non allocating write, we just change the one |
| * page. Otherwise, we'll need a whole clusters worth. |
| */ |
| if (new) |
| numpages = ocfs2_pages_per_cluster(inode->i_sb); |
| |
| cpages = kzalloc(sizeof(*cpages) * numpages, GFP_NOFS); |
| if (!cpages) { |
| ret = -ENOMEM; |
| mlog_errno(ret); |
| return ret; |
| } |
| |
| /* |
| * Fill our page array first. That way we've grabbed enough so |
| * that we can zero and flush if we error after adding the |
| * extent. |
| */ |
| if (new) { |
| start = ocfs2_align_clusters_to_page_index(inode->i_sb, |
| wc->w_cpos); |
| v_blkno = ocfs2_clusters_to_blocks(inode->i_sb, wc->w_cpos); |
| } else { |
| start = wc->w_pos >> PAGE_CACHE_SHIFT; |
| v_blkno = wc->w_pos >> inode->i_sb->s_blocksize_bits; |
| } |
| |
| for(i = 0; i < numpages; i++) { |
| index = start + i; |
| |
| cpages[i] = grab_cache_page(mapping, index); |
| if (!cpages[i]) { |
| ret = -ENOMEM; |
| mlog_errno(ret); |
| goto out; |
| } |
| } |
| |
| if (new) { |
| /* |
| * This is safe to call with the page locks - it won't take |
| * any additional semaphores or cluster locks. |
| */ |
| tmp_pos = wc->w_cpos; |
| ret = ocfs2_do_extend_allocation(OCFS2_SB(inode->i_sb), inode, |
| &tmp_pos, 1, di_bh, handle, |
| data_ac, meta_ac, NULL); |
| /* |
| * This shouldn't happen because we must have already |
| * calculated the correct meta data allocation required. The |
| * internal tree allocation code should know how to increase |
| * transaction credits itself. |
| * |
| * If need be, we could handle -EAGAIN for a |
| * RESTART_TRANS here. |
| */ |
| mlog_bug_on_msg(ret == -EAGAIN, |
| "Inode %llu: EAGAIN return during allocation.\n", |
| (unsigned long long)OCFS2_I(inode)->ip_blkno); |
| if (ret < 0) { |
| mlog_errno(ret); |
| goto out; |
| } |
| } |
| |
| ret = ocfs2_extent_map_get_blocks(inode, v_blkno, &p_blkno, NULL, |
| NULL); |
| if (ret < 0) { |
| |
| /* |
| * XXX: Should we go readonly here? |
| */ |
| |
| mlog_errno(ret); |
| goto out; |
| } |
| |
| BUG_ON(p_blkno == 0); |
| |
| for(i = 0; i < numpages; i++) { |
| ret = ocfs2_write_data_page(inode, handle, &p_blkno, cpages[i], |
| wc, new); |
| if (ret < 0) { |
| mlog_errno(ret); |
| goto out; |
| } |
| |
| copied += ret; |
| } |
| |
| out: |
| for(i = 0; i < numpages; i++) { |
| unlock_page(cpages[i]); |
| mark_page_accessed(cpages[i]); |
| page_cache_release(cpages[i]); |
| } |
| kfree(cpages); |
| |
| return copied ? copied : ret; |
| } |
| |
| static void ocfs2_write_ctxt_init(struct ocfs2_write_ctxt *wc, |
| struct ocfs2_super *osb, loff_t pos, |
| size_t count, ocfs2_page_writer *cb, |
| void *cb_priv) |
| { |
| wc->w_count = count; |
| wc->w_pos = pos; |
| wc->w_cpos = wc->w_pos >> osb->s_clustersize_bits; |
| wc->w_finished_copy = 0; |
| |
| if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits)) |
| wc->w_large_pages = 1; |
| else |
| wc->w_large_pages = 0; |
| |
| wc->w_write_data_page = cb; |
| wc->w_private = cb_priv; |
| } |
| |
| /* |
| * Write a cluster to an inode. The cluster may not be allocated yet, |
| * in which case it will be. This only exists for buffered writes - |
| * O_DIRECT takes a more "traditional" path through the kernel. |
| * |
| * The caller is responsible for incrementing pos, written counts, etc |
| * |
| * For file systems that don't support sparse files, pre-allocation |
| * and page zeroing up until cpos should be done prior to this |
| * function call. |
| * |
| * Callers should be holding i_sem, and the rw cluster lock. |
| * |
| * Returns the number of user bytes written, or less than zero for |
| * error. |
| */ |
| ssize_t ocfs2_buffered_write_cluster(struct file *file, loff_t pos, |
| size_t count, ocfs2_page_writer *actor, |
| void *priv) |
| { |
| int ret, credits = OCFS2_INODE_UPDATE_CREDITS; |
| ssize_t written = 0; |
| u32 phys; |
| struct inode *inode = file->f_mapping->host; |
| struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); |
| struct buffer_head *di_bh = NULL; |
| struct ocfs2_dinode *di; |
| struct ocfs2_alloc_context *data_ac = NULL; |
| struct ocfs2_alloc_context *meta_ac = NULL; |
| handle_t *handle; |
| struct ocfs2_write_ctxt wc; |
| |
| ocfs2_write_ctxt_init(&wc, osb, pos, count, actor, priv); |
| |
| ret = ocfs2_meta_lock(inode, &di_bh, 1); |
| if (ret) { |
| mlog_errno(ret); |
| goto out; |
| } |
| di = (struct ocfs2_dinode *)di_bh->b_data; |
| |
| /* |
| * Take alloc sem here to prevent concurrent lookups. That way |
| * the mapping, zeroing and tree manipulation within |
| * ocfs2_write() will be safe against ->readpage(). This |
| * should also serve to lock out allocation from a shared |
| * writeable region. |
| */ |
| down_write(&OCFS2_I(inode)->ip_alloc_sem); |
| |
| ret = ocfs2_get_clusters(inode, wc.w_cpos, &phys, NULL, NULL); |
| if (ret) { |
| mlog_errno(ret); |
| goto out_meta; |
| } |
| |
| /* phys == 0 means that allocation is required. */ |
| if (phys == 0) { |
| ret = ocfs2_lock_allocators(inode, di, 1, &data_ac, &meta_ac); |
| if (ret) { |
| mlog_errno(ret); |
| goto out_meta; |
| } |
| |
| credits = ocfs2_calc_extend_credits(inode->i_sb, di, 1); |
| } |
| |
| ret = ocfs2_data_lock(inode, 1); |
| if (ret) { |
| mlog_errno(ret); |
| goto out_meta; |
| } |
| |
| handle = ocfs2_start_trans(osb, credits); |
| if (IS_ERR(handle)) { |
| ret = PTR_ERR(handle); |
| mlog_errno(ret); |
| goto out_data; |
| } |
| |
| written = ocfs2_write(file, phys, handle, di_bh, data_ac, |
| meta_ac, &wc); |
| if (written < 0) { |
| ret = written; |
| mlog_errno(ret); |
| goto out_commit; |
| } |
| |
| ret = ocfs2_journal_access(handle, inode, di_bh, |
| OCFS2_JOURNAL_ACCESS_WRITE); |
| if (ret) { |
| mlog_errno(ret); |
| goto out_commit; |
| } |
| |
| pos += written; |
| if (pos > inode->i_size) { |
| i_size_write(inode, pos); |
| mark_inode_dirty(inode); |
| } |
| inode->i_blocks = ocfs2_align_bytes_to_sectors((u64)(i_size_read(inode))); |
| di->i_size = cpu_to_le64((u64)i_size_read(inode)); |
| inode->i_mtime = inode->i_ctime = CURRENT_TIME; |
| di->i_mtime = di->i_ctime = cpu_to_le64(inode->i_mtime.tv_sec); |
| di->i_mtime_nsec = di->i_ctime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec); |
| |
| ret = ocfs2_journal_dirty(handle, di_bh); |
| if (ret) |
| mlog_errno(ret); |
| |
| out_commit: |
| ocfs2_commit_trans(osb, handle); |
| |
| out_data: |
| ocfs2_data_unlock(inode, 1); |
| |
| out_meta: |
| up_write(&OCFS2_I(inode)->ip_alloc_sem); |
| ocfs2_meta_unlock(inode, 1); |
| |
| out: |
| brelse(di_bh); |
| if (data_ac) |
| ocfs2_free_alloc_context(data_ac); |
| if (meta_ac) |
| ocfs2_free_alloc_context(meta_ac); |
| |
| return written ? written : ret; |
| } |
| |
| const struct address_space_operations ocfs2_aops = { |
| .readpage = ocfs2_readpage, |
| .writepage = ocfs2_writepage, |
| .bmap = ocfs2_bmap, |
| .sync_page = block_sync_page, |
| .direct_IO = ocfs2_direct_IO, |
| .invalidatepage = ocfs2_invalidatepage, |
| .releasepage = ocfs2_releasepage, |
| .migratepage = buffer_migrate_page, |
| }; |