Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/k…

…ernel/git/steve/gfs2-3.0-nmw into next

Pull gfs2 updates from Steven Whitehouse:
 "This must be about the smallest merge window patch set ever for GFS2.
  It is probably also the first one without a single patch from me.
  That is down to a combination of factors, and I have some things in
  the works that are not quite ready yet, that I hope to put in next
  time around.

  Returning to what is here this time...  we have 3 patches which fix
  various warnings.  Two are bug fixes (for quotas and also a rare
  recovery race condition).  The final patch, from Ben Marzinski, is an
  important change in the freeze code which has been in progress for
  some time.  This removes the need to take and drop the transaction
  lock for every single transaction, when the only time it was used, was
  at file system freeze time.  Ben's patch integrates the freeze
  operation into the journal flush code as an alternative with lower
  overheads and also lands up resolving some difficult to fix races at
  the same time"

* tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw:
  GFS2: Prevent recovery before the local journal is set
  GFS2: fs/gfs2/file.c: kernel-doc warning fixes
  GFS2: fs/gfs2/bmap.c: kernel-doc warning fixes
  GFS2: remove transaction glock
  GFS2: lops.c: replace 0 by NULL for pointers
  GFS2: quotas not being refreshed in gfs2_adjust_quota

fs/gfs2/aops.c

@@ -431,7 +431,7 @@ static int gfs2_jdata_writepages(struct address_space *mapping,
 
 	ret = gfs2_write_cache_jdata(mapping, wbc);
 	if (ret == 0 && wbc->sync_mode == WB_SYNC_ALL) {
-		gfs2_log_flush(sdp, ip->i_gl);
+		gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH);
 		ret = gfs2_write_cache_jdata(mapping, wbc);
 	}
 	return ret;

fs/gfs2/bmap.c

@@ -707,7 +707,7 @@ int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsi
  * @top: The first pointer in the buffer
  * @bottom: One more than the last pointer
  * @height: the height this buffer is at
- * @data: a pointer to a struct strip_mine
+ * @sm: a pointer to a struct strip_mine
  *
  * Returns: errno
  */
@@ -992,6 +992,8 @@ static int gfs2_block_truncate_page(struct address_space *mapping, loff_t from)
 	return err;
 }
 
+#define GFS2_JTRUNC_REVOKES 8192
+
 /**
  * gfs2_journaled_truncate - Wrapper for truncate_pagecache for jdata files
  * @inode: The inode being truncated
@@ -1003,8 +1005,6 @@ static int gfs2_block_truncate_page(struct address_space *mapping, loff_t from)
  * if the number of pages being truncated gets too large.
  */
 
-#define GFS2_JTRUNC_REVOKES 8192
-
 static int gfs2_journaled_truncate(struct inode *inode, u64 oldsize, u64 newsize)
 {
 	struct gfs2_sbd *sdp = GFS2_SB(inode);
@@ -1348,7 +1348,7 @@ void gfs2_free_journal_extents(struct gfs2_jdesc *jd)
  * gfs2_add_jextent - Add or merge a new extent to extent cache
  * @jd: The journal descriptor
  * @lblock: The logical block at start of new extent
- * @pblock: The physical block at start of new extent
+ * @dblock: The physical block at start of new extent
  * @blocks: Size of extent in fs blocks
  *
  * Returns: 0 on success or -ENOMEM

fs/gfs2/file.c

@@ -203,9 +203,9 @@ void gfs2_set_inode_flags(struct inode *inode)
 			     GFS2_DIF_INHERIT_JDATA)
 
 /**
- * gfs2_set_flags - set flags on an inode
- * @inode: The inode
- * @flags: The flags to set
+ * do_gfs2_set_flags - set flags on an inode
+ * @filp: file pointer
+ * @reqflags: The flags to set
  * @mask: Indicates which flags are valid
  *
  */
@@ -256,7 +256,7 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
 	}
 	if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
 		if (flags & GFS2_DIF_JDATA)
-			gfs2_log_flush(sdp, ip->i_gl);
+			gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH);
 		error = filemap_fdatawrite(inode->i_mapping);
 		if (error)
 			goto out;
@@ -318,7 +318,7 @@ static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 
 /**
  * gfs2_size_hint - Give a hint to the size of a write request
- * @file: The struct file
+ * @filep: The struct file
  * @offset: The file offset of the write
  * @size: The length of the write
  *
@@ -371,7 +371,7 @@ static int gfs2_allocate_page_backing(struct page *page)
 /**
  * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
  * @vma: The virtual memory area
- * @page: The page which is about to become writable
+ * @vmf: The virtual memory fault containing the page to become writable
  *
  * When the page becomes writable, we need to ensure that we have
  * blocks allocated on disk to back that page.

fs/gfs2/glops.c

@@ -89,18 +89,23 @@ static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
 	if (!tr.tr_revokes)
 		return;
 
-	/* A shortened, inline version of gfs2_trans_begin() */
+	/* A shortened, inline version of gfs2_trans_begin()
+         * tr->alloced is not set since the transaction structure is
+         * on the stack */
 	tr.tr_reserved = 1 + gfs2_struct2blk(sdp, tr.tr_revokes, sizeof(u64));
 	tr.tr_ip = (unsigned long)__builtin_return_address(0);
 	sb_start_intwrite(sdp->sd_vfs);
-	gfs2_log_reserve(sdp, tr.tr_reserved);
+	if (gfs2_log_reserve(sdp, tr.tr_reserved) < 0) {
+		sb_end_intwrite(sdp->sd_vfs);
+		return;
+	}
 	WARN_ON_ONCE(current->journal_info);
 	current->journal_info = &tr;
 
 	__gfs2_ail_flush(gl, 0, tr.tr_revokes);
 
 	gfs2_trans_end(sdp);
-	gfs2_log_flush(sdp, NULL);
+	gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
 }
 
 void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
@@ -121,7 +126,7 @@ void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
 		return;
 	__gfs2_ail_flush(gl, fsync, max_revokes);
 	gfs2_trans_end(sdp);
-	gfs2_log_flush(sdp, NULL);
+	gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
 }
 
 /**
@@ -144,7 +149,7 @@ static void rgrp_go_sync(struct gfs2_glock *gl)
 		return;
 	GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
 
-	gfs2_log_flush(sdp, gl);
+	gfs2_log_flush(sdp, gl, NORMAL_FLUSH);
 	filemap_fdatawrite_range(mapping, gl->gl_vm.start, gl->gl_vm.end);
 	error = filemap_fdatawait_range(mapping, gl->gl_vm.start, gl->gl_vm.end);
 	mapping_set_error(mapping, error);
@@ -206,7 +211,7 @@ static void inode_go_sync(struct gfs2_glock *gl)
 
 	GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
 
-	gfs2_log_flush(gl->gl_sbd, gl);
+	gfs2_log_flush(gl->gl_sbd, gl, NORMAL_FLUSH);
 	filemap_fdatawrite(metamapping);
 	if (ip) {
 		struct address_space *mapping = ip->i_inode.i_mapping;
@@ -253,7 +258,7 @@ static void inode_go_inval(struct gfs2_glock *gl, int flags)
 	}
 
 	if (ip == GFS2_I(gl->gl_sbd->sd_rindex)) {
-		gfs2_log_flush(gl->gl_sbd, NULL);
+		gfs2_log_flush(gl->gl_sbd, NULL, NORMAL_FLUSH);
 		gl->gl_sbd->sd_rindex_uptodate = 0;
 	}
 	if (ip && S_ISREG(ip->i_inode.i_mode))
@@ -455,31 +460,39 @@ static void inode_go_dump(struct seq_file *seq, const struct gfs2_glock *gl)
 }
 
 /**
- * trans_go_sync - promote/demote the transaction glock
+ * freeze_go_sync - promote/demote the freeze glock
  * @gl: the glock
  * @state: the requested state
  * @flags:
  *
  */
 
-static void trans_go_sync(struct gfs2_glock *gl)
+static void freeze_go_sync(struct gfs2_glock *gl)
 {
 	struct gfs2_sbd *sdp = gl->gl_sbd;
+	DEFINE_WAIT(wait);
 
-	if (gl->gl_state != LM_ST_UNLOCKED &&
+	if (gl->gl_state == LM_ST_SHARED &&
 	    test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
-		gfs2_meta_syncfs(sdp);
-		gfs2_log_shutdown(sdp);
+		atomic_set(&sdp->sd_log_freeze, 1);
+		wake_up(&sdp->sd_logd_waitq);
+		do {
+			prepare_to_wait(&sdp->sd_log_frozen_wait, &wait,
+					TASK_UNINTERRUPTIBLE);
+			if (atomic_read(&sdp->sd_log_freeze))
+				io_schedule();
+		} while(atomic_read(&sdp->sd_log_freeze));
+		finish_wait(&sdp->sd_log_frozen_wait, &wait);
 	}
 }
 
 /**
- * trans_go_xmote_bh - After promoting/demoting the transaction glock
+ * freeze_go_xmote_bh - After promoting/demoting the freeze glock
  * @gl: the glock
  *
  */
 
-static int trans_go_xmote_bh(struct gfs2_glock *gl, struct gfs2_holder *gh)
+static int freeze_go_xmote_bh(struct gfs2_glock *gl, struct gfs2_holder *gh)
 {
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
@@ -512,7 +525,7 @@ static int trans_go_xmote_bh(struct gfs2_glock *gl, struct gfs2_holder *gh)
  * Always returns 0
  */
 
-static int trans_go_demote_ok(const struct gfs2_glock *gl)
+static int freeze_go_demote_ok(const struct gfs2_glock *gl)
 {
 	return 0;
 }
@@ -563,10 +576,10 @@ const struct gfs2_glock_operations gfs2_rgrp_glops = {
 	.go_flags = GLOF_LVB,
 };
 
-const struct gfs2_glock_operations gfs2_trans_glops = {
-	.go_sync = trans_go_sync,
-	.go_xmote_bh = trans_go_xmote_bh,
-	.go_demote_ok = trans_go_demote_ok,
+const struct gfs2_glock_operations gfs2_freeze_glops = {
+	.go_sync = freeze_go_sync,
+	.go_xmote_bh = freeze_go_xmote_bh,
+	.go_demote_ok = freeze_go_demote_ok,
 	.go_type = LM_TYPE_NONDISK,
 };
 

fs/gfs2/glops.h

@@ -15,7 +15,7 @@
 extern const struct gfs2_glock_operations gfs2_meta_glops;
 extern const struct gfs2_glock_operations gfs2_inode_glops;
 extern const struct gfs2_glock_operations gfs2_rgrp_glops;
-extern const struct gfs2_glock_operations gfs2_trans_glops;
+extern const struct gfs2_glock_operations gfs2_freeze_glops;
 extern const struct gfs2_glock_operations gfs2_iopen_glops;
 extern const struct gfs2_glock_operations gfs2_flock_glops;
 extern const struct gfs2_glock_operations gfs2_nondisk_glops;

fs/gfs2/incore.h

@@ -465,9 +465,7 @@ struct gfs2_trans {
 	unsigned int tr_reserved;
 	unsigned int tr_touched:1;
 	unsigned int tr_attached:1;
-
-	struct gfs2_holder tr_t_gh;
-
+	unsigned int tr_alloced:1;
 
 	unsigned int tr_num_buf_new;
 	unsigned int tr_num_databuf_new;
@@ -682,7 +680,7 @@ struct gfs2_sbd {
 	struct lm_lockstruct sd_lockstruct;
 	struct gfs2_holder sd_live_gh;
 	struct gfs2_glock *sd_rename_gl;
-	struct gfs2_glock *sd_trans_gl;
+	struct gfs2_glock *sd_freeze_gl;
 	wait_queue_head_t sd_glock_wait;
 	atomic_t sd_glock_disposal;
 	struct completion sd_locking_init;
@@ -730,6 +728,8 @@ struct gfs2_sbd {
 	struct gfs2_holder sd_sc_gh;
 	struct gfs2_holder sd_qc_gh;
 
+	struct completion sd_journal_ready;
+
 	/* Daemon stuff */
 
 	struct task_struct *sd_logd_process;
@@ -794,6 +794,12 @@ struct gfs2_sbd {
 
 	/* For quiescing the filesystem */
 	struct gfs2_holder sd_freeze_gh;
+	struct gfs2_holder sd_freeze_root_gh;
+	struct gfs2_holder sd_thaw_gh;
+	atomic_t sd_log_freeze;
+	atomic_t sd_frozen_root;
+	wait_queue_head_t sd_frozen_root_wait;
+	wait_queue_head_t sd_log_frozen_wait;
 
 	char sd_fsname[GFS2_FSNAME_LEN];
 	char sd_table_name[GFS2_FSNAME_LEN];

fs/gfs2/inode.c

@@ -1613,18 +1613,26 @@ int gfs2_permission(struct inode *inode, int mask)
 {
 	struct gfs2_inode *ip;
 	struct gfs2_holder i_gh;
+	struct gfs2_sbd *sdp = GFS2_SB(inode);
 	int error;
 	int unlock = 0;
+	int frozen_root = 0;
 
 
 	ip = GFS2_I(inode);
 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
-		if (mask & MAY_NOT_BLOCK)
-			return -ECHILD;
-		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
-		if (error)
-			return error;
-		unlock = 1;
+		if (unlikely(gfs2_glock_is_held_excl(sdp->sd_freeze_gl) &&
+			     inode == sdp->sd_root_dir->d_inode &&
+			     atomic_inc_not_zero(&sdp->sd_frozen_root)))
+			frozen_root = 1;
+		else {
+			if (mask & MAY_NOT_BLOCK)
+				return -ECHILD;
+			error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
+			if (error)
+				return error;
+			unlock = 1;
+		}
 	}
 
 	if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
@@ -1633,6 +1641,8 @@ int gfs2_permission(struct inode *inode, int mask)
 		error = generic_permission(inode, mask);
 	if (unlock)
 		gfs2_glock_dq_uninit(&i_gh);
+	else if (frozen_root && atomic_dec_and_test(&sdp->sd_frozen_root))
+		wake_up(&sdp->sd_frozen_root_wait);
 
 	return error;
 }
@@ -1805,19 +1815,29 @@ static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
 	struct inode *inode = dentry->d_inode;
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_holder gh;
+	struct gfs2_sbd *sdp = GFS2_SB(inode);
 	int error;
 	int unlock = 0;
+	int frozen_root = 0;
 
 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
-		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
-		if (error)
-			return error;
-		unlock = 1;
+		if (unlikely(gfs2_glock_is_held_excl(sdp->sd_freeze_gl) &&
+			     inode == sdp->sd_root_dir->d_inode &&
+			     atomic_inc_not_zero(&sdp->sd_frozen_root)))
+			frozen_root = 1;
+		else {
+			error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
+			if (error)
+				return error;
+			unlock = 1;
+		}
 	}
 
 	generic_fillattr(inode, stat);
 	if (unlock)
 		gfs2_glock_dq_uninit(&gh);
+	else if (frozen_root && atomic_dec_and_test(&sdp->sd_frozen_root))
+		wake_up(&sdp->sd_frozen_root_wait);
 
 	return 0;
 }