xfs
[Top] [All Lists]

[PATCH 23/71] xfs: implement deferred bmbt map/unmap operations

To: david@xxxxxxxxxxxxx, darrick.wong@xxxxxxxxxx
Subject: [PATCH 23/71] xfs: implement deferred bmbt map/unmap operations
From: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx>
Date: Thu, 25 Aug 2016 16:48:57 -0700
Cc: linux-xfs@xxxxxxxxxxxxxxx, xfs@xxxxxxxxxxx
Delivered-to: xfs@xxxxxxxxxxx
In-reply-to: <147216879156.4420.2446767701729565218.stgit@xxxxxxxxxxxxxxxx>
References: <147216879156.4420.2446767701729565218.stgit@xxxxxxxxxxxxxxxx>
User-agent: StGit/0.17.1-dirty
Implement deferred versions of the inode block map/unmap functions.
These will be used in subsequent patches to make reflink operations
atomic.

Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
 include/xfs_trace.h |    2 +
 include/xfs_trans.h |    1 
 libxfs/defer_item.c |  107 +++++++++++++++++++++++++++++++++++++++
 libxfs/init.c       |    1 
 libxfs/xfs_bmap.c   |  141 +++++++++++++++++++++++++++++++++++++++++++++++++++
 libxfs/xfs_bmap.h   |   11 ++++
 libxfs/xfs_defer.h  |    1 
 7 files changed, 264 insertions(+)


diff --git a/include/xfs_trace.h b/include/xfs_trace.h
index cc0e960..506f23b 100644
--- a/include/xfs_trace.h
+++ b/include/xfs_trace.h
@@ -261,6 +261,8 @@
 
 #define trace_xfs_bmap_remap_alloc(...)                ((void) 0)
 #define trace_xfs_bmap_remap_alloc_error(...)  ((void) 0)
+#define trace_xfs_bmap_deferred(...)           ((void) 0)
+#define trace_xfs_bmap_defer(...)              ((void) 0)
 
 /* set c = c to avoid unused var warnings */
 #define trace_xfs_perag_get(a,b,c,d)   ((c) = (c))
diff --git a/include/xfs_trans.h b/include/xfs_trans.h
index 739a792..44deebb 100644
--- a/include/xfs_trans.h
+++ b/include/xfs_trans.h
@@ -148,5 +148,6 @@ libxfs_trans_read_buf(
 void xfs_extent_free_init_defer_op(void);
 void xfs_rmap_update_init_defer_op(void);
 void xfs_refcount_update_init_defer_op(void);
+void xfs_bmap_update_init_defer_op(void);
 
 #endif /* __XFS_TRANS_H__ */
diff --git a/libxfs/defer_item.c b/libxfs/defer_item.c
index 133e6e1..d4cd876 100644
--- a/libxfs/defer_item.c
+++ b/libxfs/defer_item.c
@@ -32,6 +32,8 @@
 #include "xfs_alloc.h"
 #include "xfs_rmap.h"
 #include "xfs_refcount.h"
+#include "xfs_bmap.h"
+#include "xfs_inode.h"
 
 /* Dummy defer item ops, since we don't do logging. */
 
@@ -386,3 +388,108 @@ xfs_refcount_update_init_defer_op(void)
 {
        xfs_defer_init_op_type(&xfs_refcount_update_defer_type);
 }
+
+/* Inode Block Mapping */
+
+/* Sort bmap intents by inode. */
+static int
+xfs_bmap_update_diff_items(
+       void                            *priv,
+       struct list_head                *a,
+       struct list_head                *b)
+{
+       struct xfs_bmap_intent          *ba;
+       struct xfs_bmap_intent          *bb;
+
+       ba = container_of(a, struct xfs_bmap_intent, bi_list);
+       bb = container_of(b, struct xfs_bmap_intent, bi_list);
+       return ba->bi_owner->i_ino - bb->bi_owner->i_ino;
+}
+
+/* Get an BUI. */
+STATIC void *
+xfs_bmap_update_create_intent(
+       struct xfs_trans                *tp,
+       unsigned int                    count)
+{
+       return NULL;
+}
+
+/* Log bmap updates in the intent item. */
+STATIC void
+xfs_bmap_update_log_item(
+       struct xfs_trans                *tp,
+       void                            *intent,
+       struct list_head                *item)
+{
+}
+
+/* Get an BUD so we can process all the deferred rmap updates. */
+STATIC void *
+xfs_bmap_update_create_done(
+       struct xfs_trans                *tp,
+       void                            *intent,
+       unsigned int                    count)
+{
+       return NULL;
+}
+
+/* Process a deferred rmap update. */
+STATIC int
+xfs_bmap_update_finish_item(
+       struct xfs_trans                *tp,
+       struct xfs_defer_ops            *dop,
+       struct list_head                *item,
+       void                            *done_item,
+       void                            **state)
+{
+       struct xfs_bmap_intent          *bmap;
+       int                             error;
+
+       bmap = container_of(item, struct xfs_bmap_intent, bi_list);
+       error = xfs_bmap_finish_one(tp, dop,
+                       bmap->bi_owner,
+                       bmap->bi_type, bmap->bi_whichfork,
+                       bmap->bi_bmap.br_startoff,
+                       bmap->bi_bmap.br_startblock,
+                       bmap->bi_bmap.br_blockcount,
+                       bmap->bi_bmap.br_state);
+       kmem_free(bmap);
+       return error;
+}
+
+/* Abort all pending BUIs. */
+STATIC void
+xfs_bmap_update_abort_intent(
+       void                            *intent)
+{
+}
+
+/* Cancel a deferred rmap update. */
+STATIC void
+xfs_bmap_update_cancel_item(
+       struct list_head                *item)
+{
+       struct xfs_bmap_intent          *bmap;
+
+       bmap = container_of(item, struct xfs_bmap_intent, bi_list);
+       kmem_free(bmap);
+}
+
+static const struct xfs_defer_op_type xfs_bmap_update_defer_type = {
+       .type           = XFS_DEFER_OPS_TYPE_BMAP,
+       .diff_items     = xfs_bmap_update_diff_items,
+       .create_intent  = xfs_bmap_update_create_intent,
+       .abort_intent   = xfs_bmap_update_abort_intent,
+       .log_item       = xfs_bmap_update_log_item,
+       .create_done    = xfs_bmap_update_create_done,
+       .finish_item    = xfs_bmap_update_finish_item,
+       .cancel_item    = xfs_bmap_update_cancel_item,
+};
+
+/* Register the deferred op type. */
+void
+xfs_bmap_update_init_defer_op(void)
+{
+       xfs_defer_init_op_type(&xfs_bmap_update_defer_type);
+}
diff --git a/libxfs/init.c b/libxfs/init.c
index 2d1bb58..9134879 100644
--- a/libxfs/init.c
+++ b/libxfs/init.c
@@ -267,6 +267,7 @@ libxfs_init(libxfs_init_t *a)
        xfs_extent_free_init_defer_op();
        xfs_rmap_update_init_defer_op();
        xfs_refcount_update_init_defer_op();
+       xfs_bmap_update_init_defer_op();
 
        radix_tree_init();
 
diff --git a/libxfs/xfs_bmap.c b/libxfs/xfs_bmap.c
index ff99768..a919371 100644
--- a/libxfs/xfs_bmap.c
+++ b/libxfs/xfs_bmap.c
@@ -6123,3 +6123,144 @@ out:
        xfs_trans_cancel(tp);
        return error;
 }
+
+/* Deferred mapping is only for real extents in the data fork. */
+static bool
+xfs_bmap_is_update_needed(
+       int                     whichfork,
+       struct xfs_bmbt_irec    *bmap)
+{
+       ASSERT(whichfork == XFS_DATA_FORK);
+
+       return  bmap->br_startblock != HOLESTARTBLOCK &&
+               bmap->br_startblock != DELAYSTARTBLOCK;
+}
+
+/* Record a bmap intent. */
+static int
+__xfs_bmap_add(
+       struct xfs_mount                *mp,
+       struct xfs_defer_ops            *dfops,
+       enum xfs_bmap_intent_type       type,
+       struct xfs_inode                *ip,
+       int                             whichfork,
+       struct xfs_bmbt_irec            *bmap)
+{
+       int                             error;
+       struct xfs_bmap_intent          *bi;
+
+       trace_xfs_bmap_defer(mp,
+                       XFS_FSB_TO_AGNO(mp, bmap->br_startblock),
+                       type,
+                       XFS_FSB_TO_AGBNO(mp, bmap->br_startblock),
+                       ip->i_ino, whichfork,
+                       bmap->br_startoff,
+                       bmap->br_blockcount,
+                       bmap->br_state);
+
+       bi = kmem_alloc(sizeof(struct xfs_bmap_intent), KM_SLEEP | KM_NOFS);
+       INIT_LIST_HEAD(&bi->bi_list);
+       bi->bi_type = type;
+       bi->bi_owner = ip;
+       bi->bi_whichfork = whichfork;
+       bi->bi_bmap = *bmap;
+
+       error = xfs_defer_join(dfops, bi->bi_owner);
+       if (error) {
+               kmem_free(bi);
+               return error;
+       }
+
+       xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_BMAP, &bi->bi_list);
+       return 0;
+}
+
+/* Map an extent into a file. */
+int
+xfs_bmap_map_extent(
+       struct xfs_mount        *mp,
+       struct xfs_defer_ops    *dfops,
+       struct xfs_inode        *ip,
+       int                     whichfork,
+       struct xfs_bmbt_irec    *PREV)
+{
+       if (!xfs_bmap_is_update_needed(whichfork, PREV))
+               return 0;
+
+       return __xfs_bmap_add(mp, dfops, XFS_BMAP_MAP, ip, whichfork, PREV);
+}
+
+/* Unmap an extent out of a file. */
+int
+xfs_bmap_unmap_extent(
+       struct xfs_mount        *mp,
+       struct xfs_defer_ops    *dfops,
+       struct xfs_inode        *ip,
+       int                     whichfork,
+       struct xfs_bmbt_irec    *PREV)
+{
+       if (!xfs_bmap_is_update_needed(whichfork, PREV))
+               return 0;
+
+       return __xfs_bmap_add(mp, dfops, XFS_BMAP_UNMAP, ip, whichfork, PREV);
+}
+
+/*
+ * Process one of the deferred bmap operations.  We pass back the
+ * btree cursor to maintain our lock on the bmapbt between calls.
+ */
+int
+xfs_bmap_finish_one(
+       struct xfs_trans                *tp,
+       struct xfs_defer_ops            *dfops,
+       struct xfs_inode                *ip,
+       enum xfs_bmap_intent_type       type,
+       int                             whichfork,
+       xfs_fileoff_t                   startoff,
+       xfs_fsblock_t                   startblock,
+       xfs_filblks_t                   blockcount,
+       xfs_exntst_t                    state)
+{
+       struct xfs_bmbt_irec            bmap;
+       int                             nimaps = 1;
+       xfs_fsblock_t                   firstfsb;
+       int                             done;
+       int                             error = 0;
+
+       bmap.br_startblock = startblock;
+       bmap.br_startoff = startoff;
+       bmap.br_blockcount = blockcount;
+       bmap.br_state = state;
+
+       trace_xfs_bmap_deferred(tp->t_mountp,
+                       XFS_FSB_TO_AGNO(tp->t_mountp, startblock), type,
+                       XFS_FSB_TO_AGBNO(tp->t_mountp, startblock),
+                       ip->i_ino, whichfork, startoff, blockcount, state);
+
+       if (XFS_TEST_ERROR(false, tp->t_mountp,
+                       XFS_ERRTAG_BMAP_FINISH_ONE,
+                       XFS_RANDOM_BMAP_FINISH_ONE))
+               return -EIO;
+
+       switch (type) {
+       case XFS_BMAP_MAP:
+               firstfsb = bmap.br_startblock;
+               error = xfs_bmapi_write(tp, ip, bmap.br_startoff,
+                                       bmap.br_blockcount,
+                                       XFS_BMAPI_REMAP, &firstfsb,
+                                       bmap.br_blockcount, &bmap, &nimaps,
+                                       dfops);
+               break;
+       case XFS_BMAP_UNMAP:
+               error = xfs_bunmapi(tp, ip, bmap.br_startoff,
+                               bmap.br_blockcount, XFS_BMAPI_REMAP, 1, 
&firstfsb,
+                               dfops, &done);
+               ASSERT(done);
+               break;
+       default:
+               ASSERT(0);
+               error = -EFSCORRUPTED;
+       }
+
+       return error;
+}
diff --git a/libxfs/xfs_bmap.h b/libxfs/xfs_bmap.h
index 4d9b666..858788b 100644
--- a/libxfs/xfs_bmap.h
+++ b/libxfs/xfs_bmap.h
@@ -233,4 +233,15 @@ struct xfs_bmap_intent {
        struct xfs_bmbt_irec                    bi_bmap;
 };
 
+int    xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_defer_ops *dfops,
+               struct xfs_inode *ip, enum xfs_bmap_intent_type type,
+               int whichfork, xfs_fileoff_t startoff, xfs_fsblock_t startblock,
+               xfs_filblks_t blockcount, xfs_exntst_t state);
+int    xfs_bmap_map_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
+               struct xfs_inode *ip, int whichfork,
+               struct xfs_bmbt_irec *imap);
+int    xfs_bmap_unmap_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
+               struct xfs_inode *ip, int whichfork,
+               struct xfs_bmbt_irec *imap);
+
 #endif /* __XFS_BMAP_H__ */
diff --git a/libxfs/xfs_defer.h b/libxfs/xfs_defer.h
index d47a482..aa57eaa 100644
--- a/libxfs/xfs_defer.h
+++ b/libxfs/xfs_defer.h
@@ -51,6 +51,7 @@ struct xfs_defer_pending {
  * find all the space it needs.
  */
 enum xfs_defer_ops_type {
+       XFS_DEFER_OPS_TYPE_BMAP,
        XFS_DEFER_OPS_TYPE_REFCOUNT,
        XFS_DEFER_OPS_TYPE_RMAP,
        XFS_DEFER_OPS_TYPE_FREE,

<Prev in Thread] Current Thread [Next in Thread>