Commit 607d44aa authored by Mark Fasheh's avatar Mark Fasheh
Browse files

ocfs2: factor out write aops into nolock variants 



ocfs2_mkwrite() will want this so that it can add some mmap specific checks
before asking for a write.

Signed-off-by: default avatarMark Fasheh <mark.fasheh@oracle.com>
parent 3a307ffc

fs/ocfs2/aops.c

+80 −40
Original line number Diff line number Diff line
@@ -849,7 +849,7 @@ static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc) 


static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,

				  struct ocfs2_super *osb, loff_t pos,

				  unsigned len)

				  unsigned len, struct buffer_head *di_bh)

{

	struct ocfs2_write_ctxt *wc;
@@ -859,6 +859,8 @@ static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp, 


	wc->w_cpos = pos >> osb->s_clustersize_bits;

	wc->w_clen = ocfs2_clusters_for_bytes(osb->sb, len);

	get_bh(di_bh);

	wc->w_di_bh = di_bh;



	if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits))

		wc->w_large_pages = 1;
@@ -1211,9 +1213,10 @@ static void ocfs2_set_target_boundaries(struct ocfs2_super *osb, 
	}

}



int ocfs2_write_begin(struct file *file, struct address_space *mapping,

static int ocfs2_write_begin_nolock(struct address_space *mapping,

				    loff_t pos, unsigned len, unsigned flags,

		      struct page **pagep, void **fsdata)

				    struct page **pagep, void **fsdata,

				    struct buffer_head *di_bh)

{

	int ret, i, credits = OCFS2_INODE_UPDATE_CREDITS;

	unsigned int num_clusters = 0, clusters_to_alloc = 0;
@@ -1227,28 +1230,14 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping, 
	handle_t *handle;

	struct ocfs2_write_cluster_desc *desc;



	ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len);

	ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, di_bh);

	if (ret) {

		mlog_errno(ret);

		return ret;

	}



	ret = ocfs2_meta_lock(inode, &wc->w_di_bh, 1);

	if (ret) {

		mlog_errno(ret);

		goto out;

	}

	di = (struct ocfs2_dinode *)wc->w_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);



	for (i = 0; i < wc->w_clen; i++) {

		desc = &wc->w_desc[i];

		desc->c_cpos = wc->w_cpos + i;
@@ -1258,7 +1247,7 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping, 
						 &num_clusters, NULL);

			if (ret) {

				mlog_errno(ret);

				goto out_meta;

				goto out;

			}

		} else if (phys) {

			/*
@@ -1293,7 +1282,7 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping, 
					    &data_ac, &meta_ac);

		if (ret) {

			mlog_errno(ret);

			goto out_meta;

			goto out;

		}



		credits = ocfs2_calc_extend_credits(inode->i_sb, di,
@@ -1303,17 +1292,11 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping, 


	ocfs2_set_target_boundaries(osb, wc, pos, len, clusters_to_alloc);



	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;

		goto out;

	}



	wc->w_handle = handle;
@@ -1363,13 +1346,6 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping, 
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:

	ocfs2_free_write_ctxt(wc);
@@ -1380,7 +1356,58 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping, 
	return ret;

}



int ocfs2_write_end(struct file *file, struct address_space *mapping,

int ocfs2_write_begin(struct file *file, struct address_space *mapping,

		      loff_t pos, unsigned len, unsigned flags,

		      struct page **pagep, void **fsdata)

{

	int ret;

	struct buffer_head *di_bh = NULL;

	struct inode *inode = mapping->host;



	ret = ocfs2_meta_lock(inode, &di_bh, 1);

	if (ret) {

		mlog_errno(ret);

		return ret;

	}



	/*

	 * 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_data_lock(inode, 1);

	if (ret) {

		mlog_errno(ret);

		goto out_fail;

	}



	ret = ocfs2_write_begin_nolock(mapping, pos, len, flags, pagep,

				       fsdata, di_bh);

	if (ret) {

		mlog_errno(ret);

		goto out_fail_data;

	}



	brelse(di_bh);



	return 0;



out_fail_data:

	ocfs2_data_unlock(inode, 1);

out_fail:

	up_write(&OCFS2_I(inode)->ip_alloc_sem);



	brelse(di_bh);

	ocfs2_meta_unlock(inode, 1);



	return ret;

}



static int ocfs2_write_end_nolock(struct address_space *mapping,

				  loff_t pos, unsigned len, unsigned copied,

				  struct page *page, void *fsdata)

{
@@ -1444,12 +1471,25 @@ int ocfs2_write_end(struct file *file, struct address_space *mapping, 
	ocfs2_journal_dirty(handle, wc->w_di_bh);



	ocfs2_commit_trans(osb, handle);

	ocfs2_free_write_ctxt(wc);



	return copied;

}



int ocfs2_write_end(struct file *file, struct address_space *mapping,

		    loff_t pos, unsigned len, unsigned copied,

		    struct page *page, void *fsdata)

{

	int ret;

	struct inode *inode = mapping->host;



	ret = ocfs2_write_end_nolock(mapping, pos, len, copied, page, fsdata);



	ocfs2_data_unlock(inode, 1);

	up_write(&OCFS2_I(inode)->ip_alloc_sem);

	ocfs2_meta_unlock(inode, 1);

	ocfs2_free_write_ctxt(wc);



	return copied;

	return ret;

}



const struct address_space_operations ocfs2_aops = {