diff options
Diffstat (limited to 'fs/ocfs2')
| -rw-r--r-- | fs/ocfs2/aops.c | 679 | ||||
| -rw-r--r-- | fs/ocfs2/aops.h | 38 | ||||
| -rw-r--r-- | fs/ocfs2/extent_map.c | 4 | ||||
| -rw-r--r-- | fs/ocfs2/extent_map.h | 2 | ||||
| -rw-r--r-- | fs/ocfs2/file.c | 374 | ||||
| -rw-r--r-- | fs/ocfs2/file.h | 4 | ||||
| -rw-r--r-- | fs/ocfs2/ocfs2.h | 32 |
7 files changed, 1076 insertions, 57 deletions
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index f3b0cc5cba1..5ffb3702b5e 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -24,6 +24,7 @@ #include <linux/highmem.h> #include <linux/pagemap.h> #include <asm/byteorder.h> +#include <linux/swap.h> #define MLOG_MASK_PREFIX ML_FILE_IO #include <cluster/masklog.h> @@ -37,6 +38,7 @@ #include "file.h" #include "inode.h" #include "journal.h" +#include "suballoc.h" #include "super.h" #include "symlink.h" @@ -645,23 +647,27 @@ 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, @@ -673,6 +679,647 @@ 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. + */ +static 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_start + bsize) <= 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 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 int cbits = OCFS2_SB(inode->i_sb)->s_clustersize_bits; + 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, or any writes where cluster size is + * less than page size, we only need one page. Otherwise, + * allocating writes of cluster size larger than page size + * need cluster size pages. + */ + if (new && !wc->w_large_pages) + numpages = (1 << cbits) / PAGE_SIZE; + + 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); + 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); + 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, diff --git a/fs/ocfs2/aops.h b/fs/ocfs2/aops.h index f446a15eab8..eeb2c42483e 100644 --- a/fs/ocfs2/aops.h +++ b/fs/ocfs2/aops.h @@ -30,6 +30,44 @@ handle_t *ocfs2_start_walk_page_trans(struct inode *inode, unsigned from, unsigned to); +struct ocfs2_write_ctxt; +typedef int (ocfs2_page_writer)(struct inode *, struct ocfs2_write_ctxt *, + u64 *, unsigned int *, unsigned int *); + +ssize_t ocfs2_buffered_write_cluster(struct file *file, loff_t pos, + size_t count, ocfs2_page_writer *actor, + void *priv); + +struct ocfs2_write_ctxt { + size_t w_count; + loff_t w_pos; + u32 w_cpos; + unsigned int w_finished_copy; + + /* This is true if page_size > cluster_size */ + unsigned int w_large_pages; + + /* Filler callback and private data */ + ocfs2_page_writer *w_write_data_page; + void *w_private; + + /* Only valid for the filler callback */ + struct page *w_this_page; + unsigned int w_this_page_new; +}; + +struct ocfs2_buffered_write_priv { + char *b_src_buf; + const struct iovec *b_cur_iov; /* Current iovec */ + size_t b_cur_off; /* Offset in the + * current iovec */ +}; +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); + /* all ocfs2_dio_end_io()'s fault */ #define ocfs2_iocb_is_rw_locked(iocb) \ test_bit(0, (unsigned long *)&iocb->private) diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c index 3b4322fd369..937c2722b75 100644 --- a/fs/ocfs2/extent_map.c +++ b/fs/ocfs2/extent_map.c @@ -67,8 +67,8 @@ static int ocfs2_search_extent_list(struct ocfs2_extent_list *el, return ret; } -static int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, - u32 *p_cluster, u32 *num_clusters) +int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, + u32 *p_cluster, u32 *num_clusters) { int ret, i; struct buffer_head *di_bh = NULL; diff --git a/fs/ocfs2/extent_map.h b/fs/ocfs2/extent_map.h index 036e2325144..625d0ee5e04 100644 --- a/fs/ocfs2/extent_map.h +++ b/fs/ocfs2/extent_map.h @@ -25,6 +25,8 @@ #ifndef _EXTENT_MAP_H #define _EXTENT_MAP_H +int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, u32 *p_cluster, + u32 *num_clusters); int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno, int *ret_count); diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 3bcf3629265..667e5a869bf 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -33,6 +33,7 @@ #include <linux/sched.h> #include <linux/pipe_fs_i.h> #include <linux/mount.h> +#include <linux/writeback.h> #define MLOG_MASK_PREFIX ML_INODE #include <cluster/masklog.h> @@ -485,13 +486,13 @@ leave: * accessed, and lock them, reserving the appropriate number of bits. * * Called from ocfs2_extend_allocation() for file systems which don't - * support holes, and from ocfs2_prepare_write() for file systems - * which understand sparse inodes. + * support holes, and from ocfs2_write() for file systems which + * understand sparse inodes. */ -static int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di, - u32 clusters_to_add, - struct ocfs2_alloc_context **data_ac, - struct ocfs2_alloc_context **meta_ac) +int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di, + u32 clusters_to_add, + struct ocfs2_alloc_context **data_ac, + struct ocfs2_alloc_context **meta_ac) { int ret, num_free_extents; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); @@ -518,7 +519,7 @@ static int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di, * a cluster lock (because we ran out of room for another * extent) will violate ordering rules. * - * Most of the time we'll only be seeing this 1 page at a time + * Most of the time we'll only be seeing this 1 cluster at a time * anyway. */ if (!num_free_extents || @@ -596,13 +597,6 @@ static int ocfs2_extend_allocation(struct inode *inode, restart_all: BUG_ON(le32_to_cpu(fe->i_clusters) != OCFS2_I(inode)->ip_clusters); - status = ocfs2_lock_allocators(inode, fe, clusters_to_add, &data_ac, - &meta_ac); - if (status) { - mlog_errno(status); - goto leave; - } - /* blocks peope in read/write from reading our allocation * until we're done changing it. We depend on i_mutex to block * other extend/truncate calls while we're here. Ordering wrt @@ -610,6 +604,13 @@ restart_all: down_write(&OCFS2_I(inode)->ip_alloc_sem); drop_alloc_sem = 1; + status = ocfs2_lock_allocators(inode, fe, clusters_to_add, &data_ac, + &meta_ac); + if (status) { + mlog_errno(status); + goto leave; + } + credits = ocfs2_calc_extend_credits(osb->sb, fe, clusters_to_add); handle = ocfs2_start_trans(osb, credits); if (IS_ERR(handle)) { @@ -1088,10 +1089,49 @@ out: return ret; } +/* + * Will look for holes and unwritten extents in the range starting at + * pos for count bytes (inclusive). + */ +static int ocfs2_check_range_for_holes(struct inode *inode, loff_t pos, + size_t count) +{ + int ret = 0; + unsigned int extent_flags; + u32 cpos, clusters, extent_len, phys_cpos; + struct super_block *sb = inode->i_sb; + + cpos = pos >> OCFS2_SB(sb)->s_clustersize_bits; + clusters = ocfs2_clusters_for_bytes(sb, pos + count) - cpos; + + while (clusters) { + ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &extent_len, + &extent_flags); + if (ret < 0) { + mlog_errno(ret); + goto out; + } + + if (phys_cpos == 0 || (extent_flags & OCFS2_EXT_UNWRITTEN)) { + ret = 1; + break; + } + + if (extent_len > clusters) + extent_len = clusters; + + clusters -= extent_len; + cpos += extent_len; + } +out: + return ret; +} + static int ocfs2_prepare_inode_for_write(struct dentry *dentry, loff_t *ppos, size_t count, - int appending) + int appending, + int *direct_io) { int ret = 0, meta_level = appending; struct inode *inode = dentry->d_inode; @@ -1143,12 +1183,47 @@ static int ocfs2_prepare_inode_for_write(struct dentry *dentry, saved_pos = *ppos; } + if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))) { + loff_t end = saved_pos + count; + + /* + * Skip the O_DIRECT checks if we don't need + * them. + */ + if (!direct_io || !(*direct_io)) + break; + + /* + * Allowing concurrent direct writes means + * i_size changes wouldn't be synchronized, so + * one node could wind up truncating another + * nodes writes. + */ + if (end > i_size_read(inode)) { + *direct_io = 0; + break; + } + + /* + * We don't fill holes during direct io, so + * check for them here. If any are found, the + * caller will have to retake some cluster + * locks and initiate the io as buffered. + */ + ret = ocfs2_check_range_for_holes(inode, saved_pos, + count); + if (ret == 1) { + *direct_io = 0; + ret = 0; + } else if (ret < 0) + mlog_errno(ret); + break; + } + /* * The rest of this loop is concerned with legacy file * systems which don't support sparse files. */ - if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))) - break; newsize = count + saved_pos; @@ -1202,55 +1277,264 @@ out: return ret; } +static inline void +ocfs2_set_next_iovec(const struct iovec **iovp, size_t *basep, size_t bytes) +{ + const struct iovec *iov = *iovp; + size_t base = *basep; + + do { + int copy = min(bytes, iov->iov_len - base); + + bytes -= copy; + base += copy; + if (iov->iov_len == base) { + iov++; + base = 0; + } + } while (bytes); + *iovp = iov; + *basep = base; +} + +static struct page * ocfs2_get_write_source(struct ocfs2_buffered_write_priv *bp, + const struct iovec *cur_iov, + size_t iov_offset) +{ + int ret; + char *buf; + struct page *src_page = NULL; + + buf = cur_iov->iov_base + iov_offset; + + if (!segment_eq(get_fs(), KERNEL_DS)) { + /* + * Pull in the user page. We want to do this outside + * of the meta data locks in order to preserve locking + * order in case of page fault. + */ + ret = get_user_pages(current, current->mm, + (unsigned long)buf & PAGE_CACHE_MASK, 1, + 0, 0, &src_page, NULL); + if (ret == 1) + bp->b_src_buf = kmap(src_page); + else + src_page = ERR_PTR(-EFAULT); + } else { + bp->b_src_buf = buf; + } + + return src_page; +} + +static void ocfs2_put_write_source(struct ocfs2_buffered_write_priv *bp, + struct page *page) +{ + if (page) { + kunmap(page); + page_cache_release(page); + } +} + +static ssize_t ocfs2_file_buffered_write(struct file *file, loff_t *ppos, + const struct iovec *iov, + unsigned long nr_segs, + size_t count, + ssize_t o_direct_written) +{ + int ret = 0; + ssize_t copied, total = 0; + size_t iov_offset = 0; + const struct iovec *cur_iov = iov; + struct ocfs2_buffered_write_priv bp; + struct page *page; + + /* + * handle partial DIO write. Adjust cur_iov if needed. + */ + ocfs2_set_next_iovec(&cur_iov, &iov_offset, o_direct_written); + + do { + bp.b_cur_off = iov_offset; + bp.b_cur_iov = cur_iov; + + page = ocfs2_get_write_source(&bp, cur_iov, iov_offset); + if (IS_ERR(page)) { + ret = PTR_ERR(page); + goto out; + } + + copied = ocfs2_buffered_write_cluster(file, *ppos, count, + ocfs2_map_and_write_user_data, + &bp); + + ocfs2_put_write_source(&bp, page); + + if (copied < 0) { + mlog_errno(copied); + ret = copied; + goto out; + } + + total += copied; + *ppos = *ppos + copied; + count -= copied; + + ocfs2_set_next_iovec(&cur_iov, &iov_offset, copied); + } while(count); + +out: + return total ? total : ret; +} + +static int ocfs2_check_iovec(const struct iovec *iov, size_t *counted, + unsigned long *nr_segs) +{ + size_t ocount; /* original count */ + unsigned long seg; + + ocount = 0; + for (seg = 0; seg < *nr_segs; seg++) { + const struct iovec *iv = &iov[seg]; + + /* + * If any segment has a negative length, or the cumulative + * length ever wraps negative then return -EINVAL. + */ + ocount += iv->iov_len; + if (unlikely((ssize_t)(ocount|iv->iov_len) < 0)) + return -EINVAL; + if (access_ok(VERIFY_READ, iv->iov_base, iv->iov_len)) + continue; + if (seg == 0) + return -EFAULT; + *nr_segs = seg; + ocount -= iv->iov_len; /* This segment is no good */ + break; + } + + *counted = ocount; + return 0; +} + static ssize_t ocfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov, unsigned long nr_segs, loff_t pos) { - int ret, rw_level, have_alloc_sem = 0; - struct file *filp = iocb->ki_filp; - struct inode *inode = filp->f_path.dentry->d_inode; - int appending = filp->f_flags & O_APPEND ? 1 : 0; - - mlog_entry("(0x%p, %u, '%.*s')\n", filp, + int ret, direct_io, appending, rw_level, have_alloc_sem = 0; + int can_do_direct, sync = 0; + ssize_t written = 0; + size_t ocount; /* original count */ + size_t count; /* after file limit checks */ + loff_t *ppos = &iocb->ki_pos; + struct file *file = iocb->ki_filp; + struct inode *inode = file->f_path.dentry->d_inode; + + mlog_entry("(0x%p, %u, '%.*s')\n", file, (unsigned int)nr_segs, - filp->f_path.dentry->d_name.len, - filp->f_path.dentry->d_name.name); + file->f_path.dentry->d_name.len, + file->f_path.dentry->d_name.name); - /* happy write of zero bytes */ if (iocb->ki_left == 0) return 0; + ret = ocfs2_check_iovec(iov, &ocount, &nr_segs); + if (ret) + return ret; + + count = ocount; + + vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); + + appending = file->f_flags & O_APPEND ? 1 : 0; + direct_io = file->f_flags & O_DIRECT ? 1 : 0; + mutex_lock(&inode->i_mutex); + +relock: /* to match setattr's i_mutex -> i_alloc_sem -> rw_lock ordering */ - if (filp->f_flags & O_DIRECT) { - have_alloc_sem = 1; + if (direct_io) { down_read(&inode->i_alloc_sem); + have_alloc_sem = 1; } /* concurrent O_DIRECT writes are allowed */ - rw_level = (filp->f_flags & O_DIRECT) ? 0 : 1; + rw_level = !direct_io; ret = ocfs2_rw_lock(inode, rw_level); if (ret < 0) { - rw_level = -1; mlog_errno(ret); - goto out; + goto out_sems; } - ret = ocfs2_prepare_inode_for_write(filp->f_path.dentry, &iocb->ki_pos, - iocb->ki_left, appending); + can_do_direct = direct_io; + ret = ocfs2_prepare_inode_for_write(file->f_path.dentry, ppos, + iocb->ki_left, appending, + &can_do_direct); if (ret < 0) { mlog_errno(ret); goto out; } + /* + * We can't complete the direct I/O as requested, fall back to + * buffered I/O. + */ + if (direct_io && !can_do_direct) { + ocfs2_rw_unlock(inode, rw_level); + up_read(&inode->i_alloc_sem); + + have_alloc_sem = 0; + rw_level = -1; + + direct_io = 0; + sync = 1; + goto relock; + } + + if (!sync && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) + sync = 1; + + /* + * XXX: Is it ok to execute these checks a second time? + */ + ret = generic_write_checks(file, ppos, &count, S_ISBLK(inode->i_mode)); + if (ret) + goto out; + + /* + * Set pos so that sync_page_range_nolock() below understands + * where to start from. We might've moved it around via the + * calls above. The range we want to actually sync starts from + * *ppos here. + * + */ + pos = *ppos; + /* communicate with ocfs2_dio_end_io */ ocfs2_iocb_set_rw_locked(iocb); - ret = generic_file_aio_write_nolock(iocb, iov, nr_segs, iocb->ki_pos); + if (direct_io) { + written = generic_file_direct_write(iocb, iov, &nr_segs, *ppos, + ppos, count, ocount); + if (written < 0) { + ret = written; + goto out_dio; + } + } else { + written = ocfs2_file_buffered_write(file, ppos, iov, nr_segs, + count, written); + if (written < 0) { + ret = written; + if (ret != -EFAULT || ret != -ENOSPC) + mlog_errno(ret); + goto out; + } + } +out_dio: /* buffered aio wouldn't have proper lock coverage today */ - BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT)); + BUG_ON(ret == -EIOCBQUEUED && !(file->f_flags & O_DIRECT)); /* * deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io @@ -1268,14 +1552,25 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb, } out: + if (rw_level != -1) + ocfs2_rw_unlock(inode, rw_level); + +out_sems: if (have_alloc_sem) up_read(&inode->i_alloc_sem); - if (rw_level != -1) - ocfs2_rw_unlock(inode, rw_level); + + if (written > 0 && sync) { + ssize_t err; + + err = sync_page_range_nolock(inode, file->f_mapping, pos, count); + if (err < 0) + written = err; + } + mutex_unlock(&inode->i_mutex); mlog_exit(ret); - return ret; + return written ? written : ret; } static ssize_t ocfs2_file_splice_write(struct pipe_inode_info *pipe, @@ -1300,7 +1595,8 @@ static ssize_t ocfs2_file_splice_write(struct pipe_inode_info *pipe, goto out; } - ret = ocfs2_prepare_inode_for_write(out->f_path.dentry, ppos, len, 0); + ret = ocfs2_prepare_inode_for_write(out->f_path.dentry, ppos, len, 0, + NULL); if (ret < 0) { mlog_errno(ret); goto out_unlock; diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h index e2f6551604d..2c4460fced5 100644 --- a/fs/ocfs2/file.h +++ b/fs/ocfs2/file.h @@ -46,6 +46,10 @@ int ocfs2_do_extend_allocation(struct ocfs2_super *osb, struct ocfs2_alloc_context *data_ac, struct ocfs2_alloc_context *meta_ac, enum ocfs2_alloc_restarted *reason); +int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di, + u32 clusters_to_add, + struct ocfs2_alloc_context **data_ac, + struct ocfs2_alloc_context **meta_ac); int ocfs2_setattr(struct dentry *dentry, struct iattr *attr); int ocfs2_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat); diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h index faeb53f2eec..2699f7cac21 100644 --- a/fs/ocfs2/ocfs2.h +++ b/fs/ocfs2/ocfs2.h @@ -463,6 +463,38 @@ static inline unsigned long ocfs2_align_bytes_to_sectors(u64 bytes) return (unsigned long)((bytes + 511) >> 9); } +static inline unsigned int ocfs2_page_index_to_clusters(struct super_block *sb, + unsigned long pg_index) +{ + u32 clusters = pg_index; + unsigned int cbits = OCFS2_SB(sb)->s_clustersize_bits; + + if (unlikely(PAGE_CACHE_SHIFT > cbits)) + clusters = pg_index << (PAGE_CACHE_SHIFT - cbits); + else if (PAGE_CACHE_SHIFT < cbits) + clusters = pg_index >> (cbits - PAGE_CACHE_SHIFT); + + return clusters; +} + +/* + * Find the 1st page index which covers the given clusters. + */ +static inline unsigned long ocfs2_align_clusters_to_page_index(struct super_block *sb, + u32 clusters) +{ + unsigned int cbits = OCFS2_SB(sb)->s_clustersize_bits; + unsigned long index = clusters; + + if (PAGE_CACHE_SHIFT > cbits) { + index = clusters >> (PAGE_CACHE_SHIFT - cbits); + } else if (PAGE_CACHE_SHIFT < cbits) { + index = clusters << (cbits - PAGE_CACHE_SHIFT); + } + + return index; +} + #define ocfs2_set_bit ext2_set_bit #define ocfs2_clear_bit ext2_clear_bit #define ocfs2_test_bit ext2_test_bit |