1 files changed, 295 insertions, 0 deletions
diff --git a/fs/xfs/xfs_trans_extfree.c b/fs/xfs/xfs_trans_extfree.c
new file mode 100644
index 000000000..855c0b651
--- /dev/null
+++ b/fs/xfs/xfs_trans_extfree.c
@@ -0,0 +1,295 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000,2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_bit.h"
+#include "xfs_mount.h"
+#include "xfs_defer.h"
+#include "xfs_trans.h"
+#include "xfs_trans_priv.h"
+#include "xfs_extfree_item.h"
+#include "xfs_alloc.h"
+#include "xfs_bmap.h"
+#include "xfs_trace.h"
+
+/*
+ * This routine is called to allocate an "extent free done"
+ * log item that will hold nextents worth of extents.  The
+ * caller must use all nextents extents, because we are not
+ * flexible about this at all.
+ */
+struct xfs_efd_log_item *
+xfs_trans_get_efd(struct xfs_trans		*tp,
+		  struct xfs_efi_log_item	*efip,
+		  uint				nextents)
+{
+	struct xfs_efd_log_item			*efdp;
+
+	ASSERT(tp != NULL);
+	ASSERT(nextents > 0);
+
+	efdp = xfs_efd_init(tp->t_mountp, efip, nextents);
+	ASSERT(efdp != NULL);
+
+	/*
+	 * Get a log_item_desc to point at the new item.
+	 */
+	xfs_trans_add_item(tp, &efdp->efd_item);
+	return efdp;
+}
+
+/*
+ * Free an extent and log it to the EFD. Note that the transaction is marked
+ * dirty regardless of whether the extent free succeeds or fails to support the
+ * EFI/EFD lifecycle rules.
+ */
+int
+xfs_trans_free_extent(
+	struct xfs_trans	*tp,
+	struct xfs_efd_log_item	*efdp,
+	xfs_fsblock_t		start_block,
+	xfs_extlen_t		ext_len,
+	struct xfs_owner_info	*oinfo,
+	bool			skip_discard)
+{
+	struct xfs_mount	*mp = tp->t_mountp;
+	uint			next_extent;
+	xfs_agnumber_t		agno = XFS_FSB_TO_AGNO(mp, start_block);
+	xfs_agblock_t		agbno = XFS_FSB_TO_AGBNO(mp, start_block);
+	struct xfs_extent	*extp;
+	int			error;
+
+	trace_xfs_bmap_free_deferred(tp->t_mountp, agno, 0, agbno, ext_len);
+
+	error = __xfs_free_extent(tp, start_block, ext_len,
+				  oinfo, XFS_AG_RESV_NONE, skip_discard);
+	/*
+	 * Mark the transaction dirty, even on error. This ensures the
+	 * transaction is aborted, which:
+	 *
+	 * 1.) releases the EFI and frees the EFD
+	 * 2.) shuts down the filesystem
+	 */
+	tp->t_flags |= XFS_TRANS_DIRTY;
+	set_bit(XFS_LI_DIRTY, &efdp->efd_item.li_flags);
+
+	next_extent = efdp->efd_next_extent;
+	ASSERT(next_extent < efdp->efd_format.efd_nextents);
+	extp = &(efdp->efd_format.efd_extents[next_extent]);
+	extp->ext_start = start_block;
+	extp->ext_len = ext_len;
+	efdp->efd_next_extent++;
+
+	return error;
+}
+
+/* Sort bmap items by AG. */
+static int
+xfs_extent_free_diff_items(
+	void				*priv,
+	struct list_head		*a,
+	struct list_head		*b)
+{
+	struct xfs_mount		*mp = priv;
+	struct xfs_extent_free_item	*ra;
+	struct xfs_extent_free_item	*rb;
+
+	ra = container_of(a, struct xfs_extent_free_item, xefi_list);
+	rb = container_of(b, struct xfs_extent_free_item, xefi_list);
+	return  XFS_FSB_TO_AGNO(mp, ra->xefi_startblock) -
+		XFS_FSB_TO_AGNO(mp, rb->xefi_startblock);
+}
+
+/* Get an EFI. */
+STATIC void *
+xfs_extent_free_create_intent(
+	struct xfs_trans		*tp,
+	unsigned int			count)
+{
+	struct xfs_efi_log_item		*efip;
+
+	ASSERT(tp != NULL);
+	ASSERT(count > 0);
+
+	efip = xfs_efi_init(tp->t_mountp, count);
+	ASSERT(efip != NULL);
+
+	/*
+	 * Get a log_item_desc to point at the new item.
+	 */
+	xfs_trans_add_item(tp, &efip->efi_item);
+	return efip;
+}
+
+/* Log a free extent to the intent item. */
+STATIC void
+xfs_extent_free_log_item(
+	struct xfs_trans		*tp,
+	void				*intent,
+	struct list_head		*item)
+{
+	struct xfs_efi_log_item		*efip = intent;
+	struct xfs_extent_free_item	*free;
+	uint				next_extent;
+	struct xfs_extent		*extp;
+
+	free = container_of(item, struct xfs_extent_free_item, xefi_list);
+
+	tp->t_flags |= XFS_TRANS_DIRTY;
+	set_bit(XFS_LI_DIRTY, &efip->efi_item.li_flags);
+
+	/*
+	 * atomic_inc_return gives us the value after the increment;
+	 * we want to use it as an array index so we need to subtract 1 from
+	 * it.
+	 */
+	next_extent = atomic_inc_return(&efip->efi_next_extent) - 1;
+	ASSERT(next_extent < efip->efi_format.efi_nextents);
+	extp = &efip->efi_format.efi_extents[next_extent];
+	extp->ext_start = free->xefi_startblock;
+	extp->ext_len = free->xefi_blockcount;
+}
+
+/* Get an EFD so we can process all the free extents. */
+STATIC void *
+xfs_extent_free_create_done(
+	struct xfs_trans		*tp,
+	void				*intent,
+	unsigned int			count)
+{
+	return xfs_trans_get_efd(tp, intent, count);
+}
+
+/* Process a free extent. */
+STATIC int
+xfs_extent_free_finish_item(
+	struct xfs_trans		*tp,
+	struct list_head		*item,
+	void				*done_item,
+	void				**state)
+{
+	struct xfs_extent_free_item	*free;
+	int				error;
+
+	free = container_of(item, struct xfs_extent_free_item, xefi_list);
+	error = xfs_trans_free_extent(tp, done_item,
+			free->xefi_startblock,
+			free->xefi_blockcount,
+			&free->xefi_oinfo, free->xefi_skip_discard);
+	kmem_free(free);
+	return error;
+}
+
+/* Abort all pending EFIs. */
+STATIC void
+xfs_extent_free_abort_intent(
+	void				*intent)
+{
+	xfs_efi_release(intent);
+}
+
+/* Cancel a free extent. */
+STATIC void
+xfs_extent_free_cancel_item(
+	struct list_head		*item)
+{
+	struct xfs_extent_free_item	*free;
+
+	free = container_of(item, struct xfs_extent_free_item, xefi_list);
+	kmem_free(free);
+}
+
+static const struct xfs_defer_op_type xfs_extent_free_defer_type = {
+	.type		= XFS_DEFER_OPS_TYPE_FREE,
+	.max_items	= XFS_EFI_MAX_FAST_EXTENTS,
+	.diff_items	= xfs_extent_free_diff_items,
+	.create_intent	= xfs_extent_free_create_intent,
+	.abort_intent	= xfs_extent_free_abort_intent,
+	.log_item	= xfs_extent_free_log_item,
+	.create_done	= xfs_extent_free_create_done,
+	.finish_item	= xfs_extent_free_finish_item,
+	.cancel_item	= xfs_extent_free_cancel_item,
+};
+
+/*
+ * AGFL blocks are accounted differently in the reserve pools and are not
+ * inserted into the busy extent list.
+ */
+STATIC int
+xfs_agfl_free_finish_item(
+	struct xfs_trans		*tp,
+	struct list_head		*item,
+	void				*done_item,
+	void				**state)
+{
+	struct xfs_mount		*mp = tp->t_mountp;
+	struct xfs_efd_log_item		*efdp = done_item;
+	struct xfs_extent_free_item	*free;
+	struct xfs_extent		*extp;
+	struct xfs_buf			*agbp;
+	int				error;
+	xfs_agnumber_t			agno;
+	xfs_agblock_t			agbno;
+	uint				next_extent;
+
+	free = container_of(item, struct xfs_extent_free_item, xefi_list);
+	ASSERT(free->xefi_blockcount == 1);
+	agno = XFS_FSB_TO_AGNO(mp, free->xefi_startblock);
+	agbno = XFS_FSB_TO_AGBNO(mp, free->xefi_startblock);
+
+	trace_xfs_agfl_free_deferred(mp, agno, 0, agbno, free->xefi_blockcount);
+
+	error = xfs_alloc_read_agf(mp, tp, agno, 0, &agbp);
+	if (!error)
+		error = xfs_free_agfl_block(tp, agno, agbno, agbp,
+					    &free->xefi_oinfo);
+
+	/*
+	 * Mark the transaction dirty, even on error. This ensures the
+	 * transaction is aborted, which:
+	 *
+	 * 1.) releases the EFI and frees the EFD
+	 * 2.) shuts down the filesystem
+	 */
+	tp->t_flags |= XFS_TRANS_DIRTY;
+	set_bit(XFS_LI_DIRTY, &efdp->efd_item.li_flags);
+
+	next_extent = efdp->efd_next_extent;
+	ASSERT(next_extent < efdp->efd_format.efd_nextents);
+	extp = &(efdp->efd_format.efd_extents[next_extent]);
+	extp->ext_start = free->xefi_startblock;
+	extp->ext_len = free->xefi_blockcount;
+	efdp->efd_next_extent++;
+
+	kmem_free(free);
+	return error;
+}
+
+
+/* sub-type with special handling for AGFL deferred frees */
+static const struct xfs_defer_op_type xfs_agfl_free_defer_type = {
+	.type		= XFS_DEFER_OPS_TYPE_AGFL_FREE,
+	.max_items	= XFS_EFI_MAX_FAST_EXTENTS,
+	.diff_items	= xfs_extent_free_diff_items,
+	.create_intent	= xfs_extent_free_create_intent,
+	.abort_intent	= xfs_extent_free_abort_intent,
+	.log_item	= xfs_extent_free_log_item,
+	.create_done	= xfs_extent_free_create_done,
+	.finish_item	= xfs_agfl_free_finish_item,
+	.cancel_item	= xfs_extent_free_cancel_item,
+};
+
+/* Register the deferred op type. */
+void
+xfs_extent_free_init_defer_op(void)
+{
+	xfs_defer_init_op_type(&xfs_extent_free_defer_type);
+	xfs_defer_init_op_type(&xfs_agfl_free_defer_type);
+}