diff options
Diffstat (limited to 'fs/ocfs2/aops.c')
| -rw-r--r-- | fs/ocfs2/aops.c | 1011 |
1 files changed, 820 insertions, 191 deletions
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 875c11443817..56963e6c46c0 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -24,6 +24,8 @@ #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> @@ -37,6 +39,7 @@ #include "file.h" #include "inode.h" #include "journal.h" +#include "suballoc.h" #include "super.h" #include "symlink.h" @@ -134,7 +137,9 @@ 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); @@ -149,17 +154,8 @@ static int ocfs2_get_block(struct inode *inode, sector_t iblock, 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); + 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, @@ -167,22 +163,39 @@ static int ocfs2_get_block(struct inode *inode, sector_t iblock, 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 = %llu blkno=(%llu)\n", - (unsigned long long)iblock, - (unsigned long long)p_blkno, - (unsigned long long)OCFS2_I(inode)->ip_blkno); - } + /* + * 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); + 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); + if (create && (iblock >= past_eof)) + set_buffer_new(bh_result); + } bail: if (err < 0) @@ -276,8 +289,11 @@ static int ocfs2_writepage(struct page *page, struct writeback_control *wbc) return ret; } -/* This can also be called from ocfs2_write_zero_page() which has done - * it's own cluster locking. */ +/* + * 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) { @@ -292,44 +308,17 @@ int ocfs2_prepare_write_nolock(struct inode *inode, struct page *page, 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(). - */ -static 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, 0, page); - if (ret != 0) { - mlog_errno(ret); - goto out; - } - - ret = ocfs2_prepare_write_nolock(inode, page, from, to); - - 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)) +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; @@ -388,95 +377,6 @@ out: return handle; } -static int ocfs2_commit_write(struct file *file, struct page *page, - unsigned from, unsigned to) -{ - int ret; - struct buffer_head *di_bh = NULL; - struct inode *inode = page->mapping->host; - handle_t *handle = NULL; - struct ocfs2_dinode *di; - - 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 continue here without rechecking the I/O against - * changed inode values. - * - * 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, suid removal, etc. - * The meta data update code then ensures that we don't get a - * stale inode allocation image (i_size, i_clusters, etc). - */ - - ret = ocfs2_meta_lock_with_page(inode, &di_bh, 1, 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; - } - - handle = ocfs2_start_walk_page_trans(inode, page, from, to); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - 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; - } - - di = (struct ocfs2_dinode *)di_bh->b_data; - - /* ocfs2_mark_inode_dirty() is too heavy to use here. */ - 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); - - inode->i_blocks = ocfs2_align_bytes_to_sectors((u64)(i_size_read(inode))); - di->i_size = cpu_to_le64((u64)i_size_read(inode)); - - ret = ocfs2_journal_dirty(handle, di_bh); - if (ret < 0) { - mlog_errno(ret); - goto out_commit; - } - -out_commit: - ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle); -out_unlock_data: - ocfs2_data_unlock(inode, 1); -out_unlock_meta: - ocfs2_meta_unlock(inode, 1); -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; @@ -499,8 +399,7 @@ static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block) down_read(&OCFS2_I(inode)->ip_alloc_sem); } - err = ocfs2_extent_map_get_blocks(inode, block, 1, &p_blkno, - NULL); + err = ocfs2_extent_map_get_blocks(inode, block, &p_blkno, NULL, NULL); if (!INODE_JOURNAL(inode)) { up_read(&OCFS2_I(inode)->ip_alloc_sem); @@ -540,8 +439,8 @@ 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; + u64 p_blkno, inode_blocks, 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; @@ -549,33 +448,20 @@ static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock, * nicely aligned and of the right size, so there's no need * for us to check any of that. */ - spin_lock(&OCFS2_I(inode)->ip_lock); - inode_blocks = ocfs2_clusters_to_blocks(inode->i_sb, - OCFS2_I(inode)->ip_clusters); - - /* - * For a read which begins past the end of file, we return a hole. - */ - if (!create && (iblock >= inode_blocks)) { - spin_unlock(&OCFS2_I(inode)->ip_lock); - ret = 0; - goto bail; - } + 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) { - 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); + 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); @@ -583,7 +469,37 @@ static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock, goto bail; } - map_bh(bh_result, inode->i_sb, p_blkno); + 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. */ @@ -606,12 +522,17 @@ static void ocfs2_dio_end_io(struct kiocb *iocb, void *private) { struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode; + int level; /* 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); + + level = ocfs2_iocb_rw_locked_level(iocb); + if (!level) + up_read(&inode->i_alloc_sem); + ocfs2_rw_unlock(inode, level); } /* @@ -647,23 +568,27 @@ static ssize_t ocfs2_direct_IO(int rw, mlog_entry_void(); - /* - * 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; + 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); } - ocfs2_data_unlock(inode, 0); ret = blockdev_direct_IO_no_locking(rw, iocb, inode, inode->i_sb->s_bdev, iov, offset, @@ -675,11 +600,715 @@ out: 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_inode_sector_count(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, - .prepare_write = ocfs2_prepare_write, - .commit_write = ocfs2_commit_write, .bmap = ocfs2_bmap, .sync_page = block_sync_page, .direct_IO = ocfs2_direct_IO, |