svn commit: r356819 - in head/sys: geom ufs/ffs

[Warner Losh]

Author: imp
Date: Fri Jan 17 01:16:19 2020
New Revision: 356819
URL: https://svnweb.freebsd.org/changeset/base/356819

Log:
  Use buf to send speedup
  
  It turns out there's a problem with using g_io to send the speedup. It leads to
  a race when there's a resource shortage when a disk fails.
  
  Instead, send BIO_SPEEDUP via struct buf. This is pretty straight forward,
  except we need to transfer the bio_flags from b_ioflags for BIO_SPEEDUP commands
  in g_vfs_strategy.
  
  Reviewed by: kirk, chs
  Differential Revision: https://reviews.freebsd.org/D23117

Modified:
  head/sys/geom/geom_vfs.c
  head/sys/ufs/ffs/ffs_softdep.c

Modified: head/sys/geom/geom_vfs.c
==============================================================================
--- head/sys/geom/geom_vfs.c	Fri Jan 17 01:15:55 2020	(r356818)
+++ head/sys/geom/geom_vfs.c	Fri Jan 17 01:16:19 2020	(r356819)
@@ -191,6 +191,8 @@ g_vfs_strategy(struct bufobj *bo, struct buf *bp)
 		bip->bio_flags |= BIO_ORDERED;
 		bp->b_flags &= ~B_BARRIER;
 	}
+	if (bp->b_iocmd == BIO_SPEEDUP)
+		bip->bio_flags |= bp->b_ioflags;
 	bip->bio_done = g_vfs_done;
 	bip->bio_caller2 = bp;
 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)

Modified: head/sys/ufs/ffs/ffs_softdep.c
==============================================================================
--- head/sys/ufs/ffs/ffs_softdep.c	Fri Jan 17 01:15:55 2020	(r356818)
+++ head/sys/ufs/ffs/ffs_softdep.c	Fri Jan 17 01:16:19 2020	(r356819)
@@ -87,6 +87,7 @@ __FBSDID("$FreeBSD$");
 #include <vm/vm_object.h>
 
 #include <geom/geom.h>
+#include <geom/geom_vfs.h>
 
 #include <ddb/ddb.h>
 
@@ -1452,6 +1453,20 @@ worklist_speedup(mp)
 	wakeup(&ump->softdep_flushtd);
 }
 
+static void
+softdep_send_speedup(struct ufsmount *ump, size_t shortage, u_int flags)
+{
+	struct buf *bp;
+
+	bp = malloc(sizeof(*bp), M_TRIM, M_WAITOK | M_ZERO);
+	bp->b_iocmd = BIO_SPEEDUP;
+	bp->b_ioflags = flags;
+	bp->b_bcount = shortage;
+	g_vfs_strategy(ump->um_bo, bp);
+	bufwait(bp);
+	free(bp, M_TRIM);
+}
+
 static int
 softdep_speedup(ump)
 	struct ufsmount *ump;
@@ -13364,7 +13379,6 @@ softdep_request_cleanup(fs, vp, cred, resource)
 	struct ufsmount *ump;
 	struct mount *mp;
 	long starttime;
-	size_t resid;
 	ufs2_daddr_t needed;
 	int error, failed_vnode;
 
@@ -13442,8 +13456,8 @@ softdep_request_cleanup(fs, vp, cred, resource)
 retry:
 	if (resource == FLUSH_BLOCKS_WAIT &&
 	    fs->fs_cstotal.cs_nbfree <= needed)
-		g_io_speedup(needed * fs->fs_bsize, BIO_SPEEDUP_TRIM, &resid,
-		    ump->um_cp);
+		softdep_send_speedup(ump, needed * fs->fs_bsize,
+		    BIO_SPEEDUP_TRIM);
 	if ((resource == FLUSH_BLOCKS_WAIT && ump->softdep_on_worklist > 0 &&
 	    fs->fs_cstotal.cs_nbfree <= needed) ||
 	    (resource == FLUSH_INODES_WAIT && fs->fs_pendinginodes > 0 &&
@@ -13757,7 +13771,6 @@ check_clear_deps(mp)
 	struct mount *mp;
 {
 	struct ufsmount *ump;
-	size_t resid;
 
 	/*
 	 * Tell the lower layers that any TRIM or WRITE transactions
@@ -13766,7 +13779,7 @@ check_clear_deps(mp)
 	 */
 	ump = VFSTOUFS(mp);
 	FREE_LOCK(ump);
-	g_io_speedup(0, BIO_SPEEDUP_TRIM | BIO_SPEEDUP_WRITE, &resid, ump->um_cp);
+	softdep_send_speedup(ump, 0, BIO_SPEEDUP_TRIM | BIO_SPEEDUP_WRITE);
 	ACQUIRE_LOCK(ump);