1 files changed, 612 insertions, 83 deletions

diff --git a/fs/xfs/libxfs/xfs_trans_resv.c b/fs/xfs/libxfs/xfs_trans_resv.c
index 6cd45e8c118d..86a111d0f2fc 100644
--- a/fs/xfs/libxfs/xfs_trans_resv.c
+++ b/fs/xfs/libxfs/xfs_trans_resv.c
@@ -20,6 +20,14 @@
 #include "xfs_qm.h"
 #include "xfs_trans_space.h"
 #include "xfs_rtbitmap.h"
+#include "xfs_attr_item.h"
+#include "xfs_log.h"
+#include "xfs_defer.h"
+#include "xfs_bmap_item.h"
+#include "xfs_extfree_item.h"
+#include "xfs_rmap_item.h"
+#include "xfs_refcount_item.h"
+#include "xfs_trace.h"
 
 #define _ALLOC	true
 #define _FREE	false
@@ -90,6 +98,14 @@ xfs_refcountbt_block_count(
 	return num_ops * (2 * mp->m_refc_maxlevels - 1);
 }
 
+static unsigned int
+xfs_rtrefcountbt_block_count(
+	struct xfs_mount	*mp,
+	unsigned int		num_ops)
+{
+	return num_ops * (2 * mp->m_rtrefc_maxlevels - 1);
+}
+
 /*
  * Logging inodes is really tricksy. They are logged in memory format,
  * which means that what we write into the log doesn't directly translate into
@@ -128,7 +144,7 @@ xfs_calc_inode_res(
 		(4 * sizeof(struct xlog_op_header) +
 		 sizeof(struct xfs_inode_log_format) +
 		 mp->m_sb.sb_inodesize +
-		 2 * XFS_BMBT_BLOCK_LEN(mp));
+		 2 * xfs_bmbt_block_len(mp));
 }
 
 /*
@@ -211,7 +227,9 @@ xfs_calc_inode_chunk_res(
  * Per-extent log reservation for the btree changes involved in freeing or
  * allocating a realtime extent.  We have to be able to log as many rtbitmap
  * blocks as needed to mark inuse XFS_BMBT_MAX_EXTLEN blocks' worth of realtime
- * extents, as well as the realtime summary block.
+ * extents, as well as the realtime summary block (t1).  Realtime rmap btree
+ * operations happen in a second transaction, so factor in a couple of rtrmapbt
+ * splits (t2).
  */
 static unsigned int
 xfs_rtalloc_block_count(
@@ -220,10 +238,16 @@ xfs_rtalloc_block_count(
 {
 	unsigned int		rtbmp_blocks;
 	xfs_rtxlen_t		rtxlen;
+	unsigned int		t1, t2 = 0;
 
 	rtxlen = xfs_extlen_to_rtxlen(mp, XFS_MAX_BMBT_EXTLEN);
-	rtbmp_blocks = xfs_rtbitmap_blockcount(mp, rtxlen);
-	return (rtbmp_blocks + 1) * num_ops;
+	rtbmp_blocks = xfs_rtbitmap_blockcount_len(mp, rtxlen);
+	t1 = (rtbmp_blocks + 1) * num_ops;
+
+	if (xfs_has_rmapbt(mp))
+		t2 = num_ops * (2 * mp->m_rtrmap_maxlevels - 1);
+
+	return max(t1, t2);
 }
 
 /*
@@ -246,26 +270,64 @@ xfs_rtalloc_block_count(
  */
 
 /*
+ * Finishing a data device refcount updates (t1):
+ *    the agfs of the ags containing the blocks: nr_ops * sector size
+ *    the refcount btrees: nr_ops * 1 trees * (2 * max depth - 1) * block size
+ */
+inline unsigned int
+xfs_calc_finish_cui_reservation(
+	struct xfs_mount	*mp,
+	unsigned int		nr_ops)
+{
+	if (!xfs_has_reflink(mp))
+		return 0;
+
+	return xfs_calc_buf_res(nr_ops, mp->m_sb.sb_sectsize) +
+	       xfs_calc_buf_res(xfs_refcountbt_block_count(mp, nr_ops),
+			       mp->m_sb.sb_blocksize);
+}
+
+/*
+ * Realtime refcount updates (t2);
+ *    the rt refcount inode
+ *    the rtrefcount btrees: nr_ops * 1 trees * (2 * max depth - 1) * block size
+ */
+inline unsigned int
+xfs_calc_finish_rt_cui_reservation(
+	struct xfs_mount	*mp,
+	unsigned int		nr_ops)
+{
+	if (!xfs_has_rtreflink(mp))
+		return 0;
+
+	return xfs_calc_inode_res(mp, 1) +
+	       xfs_calc_buf_res(xfs_rtrefcountbt_block_count(mp, nr_ops),
+				     mp->m_sb.sb_blocksize);
+}
+
+/*
  * Compute the log reservation required to handle the refcount update
  * transaction.  Refcount updates are always done via deferred log items.
  *
- * This is calculated as:
+ * This is calculated as the max of:
  * Data device refcount updates (t1):
  *    the agfs of the ags containing the blocks: nr_ops * sector size
  *    the refcount btrees: nr_ops * 1 trees * (2 * max depth - 1) * block size
+ * Realtime refcount updates (t2);
+ *    the rt refcount inode
+ *    the rtrefcount btrees: nr_ops * 1 trees * (2 * max depth - 1) * block size
  */
 static unsigned int
 xfs_calc_refcountbt_reservation(
 	struct xfs_mount	*mp,
 	unsigned int		nr_ops)
 {
-	unsigned int		blksz = XFS_FSB_TO_B(mp, 1);
+	unsigned int		t1, t2;
 
-	if (!xfs_has_reflink(mp))
-		return 0;
+	t1 = xfs_calc_finish_cui_reservation(mp, nr_ops);
+	t2 = xfs_calc_finish_rt_cui_reservation(mp, nr_ops);
 
-	return xfs_calc_buf_res(nr_ops, mp->m_sb.sb_sectsize) +
-	       xfs_calc_buf_res(xfs_refcountbt_block_count(mp, nr_ops), blksz);
+	return max(t1, t2);
 }
 
 /*
@@ -336,11 +398,11 @@ xfs_calc_write_reservation(
 					blksz);
 		t1 += adj;
 		t3 += adj;
-		return XFS_DQUOT_LOGRES(mp) + max3(t1, t2, t3);
+		return XFS_DQUOT_LOGRES + max3(t1, t2, t3);
 	}
 
 	t4 = xfs_calc_refcountbt_reservation(mp, 1);
-	return XFS_DQUOT_LOGRES(mp) + max(t4, max3(t1, t2, t3));
+	return XFS_DQUOT_LOGRES + max(t4, max3(t1, t2, t3));
 }
 
 unsigned int
@@ -351,6 +413,96 @@ xfs_calc_write_reservation_minlogsize(
 }
 
 /*
+ * Finishing an EFI can free the blocks and bmap blocks (t2):
+ *    the agf for each of the ags: nr * sector size
+ *    the agfl for each of the ags: nr * sector size
+ *    the super block to reflect the freed blocks: sector size
+ *    worst case split in allocation btrees per extent assuming nr extents:
+ *		nr exts * 2 trees * (2 * max depth - 1) * block size
+ */
+inline unsigned int
+xfs_calc_finish_efi_reservation(
+	struct xfs_mount	*mp,
+	unsigned int		nr)
+{
+	return xfs_calc_buf_res((2 * nr) + 1, mp->m_sb.sb_sectsize) +
+	       xfs_calc_buf_res(xfs_allocfree_block_count(mp, nr),
+			       mp->m_sb.sb_blocksize);
+}
+
+/*
+ * Or, if it's a realtime file (t3):
+ *    the agf for each of the ags: 2 * sector size
+ *    the agfl for each of the ags: 2 * sector size
+ *    the super block to reflect the freed blocks: sector size
+ *    the realtime bitmap:
+ *		2 exts * ((XFS_BMBT_MAX_EXTLEN / rtextsize) / NBBY) bytes
+ *    the realtime summary: 2 exts * 1 block
+ *    worst case split in allocation btrees per extent assuming 2 extents:
+ *		2 exts * 2 trees * (2 * max depth - 1) * block size
+ */
+inline unsigned int
+xfs_calc_finish_rt_efi_reservation(
+	struct xfs_mount	*mp,
+	unsigned int		nr)
+{
+	if (!xfs_has_realtime(mp))
+		return 0;
+
+	return xfs_calc_buf_res((2 * nr) + 1, mp->m_sb.sb_sectsize) +
+	       xfs_calc_buf_res(xfs_rtalloc_block_count(mp, nr),
+			       mp->m_sb.sb_blocksize) +
+	       xfs_calc_buf_res(xfs_allocfree_block_count(mp, nr),
+			       mp->m_sb.sb_blocksize);
+}
+
+/*
+ * Finishing an RUI is the same as an EFI.  We can split the rmap btree twice
+ * on each end of the record, and that can cause the AGFL to be refilled or
+ * emptied out.
+ */
+inline unsigned int
+xfs_calc_finish_rui_reservation(
+	struct xfs_mount	*mp,
+	unsigned int		nr)
+{
+	if (!xfs_has_rmapbt(mp))
+		return 0;
+	return xfs_calc_finish_efi_reservation(mp, nr);
+}
+
+/*
+ * Finishing an RUI is the same as an EFI.  We can split the rmap btree twice
+ * on each end of the record, and that can cause the AGFL to be refilled or
+ * emptied out.
+ */
+inline unsigned int
+xfs_calc_finish_rt_rui_reservation(
+	struct xfs_mount	*mp,
+	unsigned int		nr)
+{
+	if (!xfs_has_rtrmapbt(mp))
+		return 0;
+	return xfs_calc_finish_rt_efi_reservation(mp, nr);
+}
+
+/*
+ * In finishing a BUI, we can modify:
+ *    the inode being truncated: inode size
+ *    dquots
+ *    the inode's bmap btree: (max depth + 1) * block size
+ */
+inline unsigned int
+xfs_calc_finish_bui_reservation(
+	struct xfs_mount	*mp,
+	unsigned int		nr)
+{
+	return xfs_calc_inode_res(mp, 1) + XFS_DQUOT_LOGRES +
+	       xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) + 1,
+			       mp->m_sb.sb_blocksize);
+}
+
+/*
  * In truncating a file we free up to two extents at once.  We can modify (t1):
  *    the inode being truncated: inode size
  *    the inode's bmap btree: (max depth + 1) * block size
@@ -382,16 +534,8 @@ xfs_calc_itruncate_reservation(
 	t1 = xfs_calc_inode_res(mp, 1) +
 	     xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) + 1, blksz);
 
-	t2 = xfs_calc_buf_res(9, mp->m_sb.sb_sectsize) +
-	     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 4), blksz);
-
-	if (xfs_has_realtime(mp)) {
-		t3 = xfs_calc_buf_res(5, mp->m_sb.sb_sectsize) +
-		     xfs_calc_buf_res(xfs_rtalloc_block_count(mp, 2), blksz) +
-		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2), blksz);
-	} else {
-		t3 = 0;
-	}
+	t2 = xfs_calc_finish_efi_reservation(mp, 4);
+	t3 = xfs_calc_finish_rt_efi_reservation(mp, 2);
 
 	/*
 	 * In the early days of reflink, we included enough reservation to log
@@ -408,11 +552,11 @@ xfs_calc_itruncate_reservation(
 					xfs_refcountbt_block_count(mp, 4),
 					blksz);
 
-		return XFS_DQUOT_LOGRES(mp) + max3(t1, t2, t3);
+		return XFS_DQUOT_LOGRES + max3(t1, t2, t3);
 	}
 
 	t4 = xfs_calc_refcountbt_reservation(mp, 2);
-	return XFS_DQUOT_LOGRES(mp) + max(t4, max3(t1, t2, t3));
+	return XFS_DQUOT_LOGRES + max(t4, max3(t1, t2, t3));
 }
 
 unsigned int
@@ -422,29 +566,108 @@ xfs_calc_itruncate_reservation_minlogsize(
 	return xfs_calc_itruncate_reservation(mp, true);
 }
 
+static inline unsigned int xfs_calc_pptr_link_overhead(void)
+{
+	return sizeof(struct xfs_attri_log_format) +
+			xlog_calc_iovec_len(sizeof(struct xfs_parent_rec)) +
+			xlog_calc_iovec_len(MAXNAMELEN - 1);
+}
+static inline unsigned int xfs_calc_pptr_unlink_overhead(void)
+{
+	return sizeof(struct xfs_attri_log_format) +
+			xlog_calc_iovec_len(sizeof(struct xfs_parent_rec)) +
+			xlog_calc_iovec_len(MAXNAMELEN - 1);
+}
+static inline unsigned int xfs_calc_pptr_replace_overhead(void)
+{
+	return sizeof(struct xfs_attri_log_format) +
+			xlog_calc_iovec_len(sizeof(struct xfs_parent_rec)) +
+			xlog_calc_iovec_len(MAXNAMELEN - 1) +
+			xlog_calc_iovec_len(sizeof(struct xfs_parent_rec)) +
+			xlog_calc_iovec_len(MAXNAMELEN - 1);
+}
+
 /*
  * In renaming a files we can modify:
  *    the five inodes involved: 5 * inode size
  *    the two directory btrees: 2 * (max depth + v2) * dir block size
  *    the two directory bmap btrees: 2 * max depth * block size
  * And the bmap_finish transaction can free dir and bmap blocks (two sets
- *	of bmap blocks) giving:
+ *	of bmap blocks) giving (t2):
  *    the agf for the ags in which the blocks live: 3 * sector size
  *    the agfl for the ags in which the blocks live: 3 * sector size
  *    the superblock for the free block count: sector size
  *    the allocation btrees: 3 exts * 2 trees * (2 * max depth - 1) * block size
+ * If parent pointers are enabled (t3), then each transaction in the chain
+ *    must be capable of setting or removing the extended attribute
+ *    containing the parent information.  It must also be able to handle
+ *    the three xattr intent items that track the progress of the parent
+ *    pointer update.
  */
 STATIC uint
 xfs_calc_rename_reservation(
 	struct xfs_mount	*mp)
 {
-	return XFS_DQUOT_LOGRES(mp) +
-		max((xfs_calc_inode_res(mp, 5) +
-		     xfs_calc_buf_res(2 * XFS_DIROP_LOG_COUNT(mp),
-				      XFS_FSB_TO_B(mp, 1))),
-		    (xfs_calc_buf_res(7, mp->m_sb.sb_sectsize) +
-		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 3),
-				      XFS_FSB_TO_B(mp, 1))));
+	unsigned int		overhead = XFS_DQUOT_LOGRES;
+	struct xfs_trans_resv	*resp = M_RES(mp);
+	unsigned int		t1, t2, t3 = 0;
+
+	t1 = xfs_calc_inode_res(mp, 5) +
+	     xfs_calc_buf_res(2 * XFS_DIROP_LOG_COUNT(mp),
+			XFS_FSB_TO_B(mp, 1));
+
+	t2 = xfs_calc_finish_efi_reservation(mp, 3);
+
+	if (xfs_has_parent(mp)) {
+		unsigned int	rename_overhead, exchange_overhead;
+
+		t3 = max(resp->tr_attrsetm.tr_logres,
+			 resp->tr_attrrm.tr_logres);
+
+		/*
+		 * For a standard rename, the three xattr intent log items
+		 * are (1) replacing the pptr for the source file; (2)
+		 * removing the pptr on the dest file; and (3) adding a
+		 * pptr for the whiteout file in the src dir.
+		 *
+		 * For an RENAME_EXCHANGE, there are two xattr intent
+		 * items to replace the pptr for both src and dest
+		 * files.  Link counts don't change and there is no
+		 * whiteout.
+		 *
+		 * In the worst case we can end up relogging all log
+		 * intent items to allow the log tail to move ahead, so
+		 * they become overhead added to each transaction in a
+		 * processing chain.
+		 */
+		rename_overhead = xfs_calc_pptr_replace_overhead() +
+				  xfs_calc_pptr_unlink_overhead() +
+				  xfs_calc_pptr_link_overhead();
+		exchange_overhead = 2 * xfs_calc_pptr_replace_overhead();
+
+		overhead += max(rename_overhead, exchange_overhead);
+	}
+
+	return overhead + max3(t1, t2, t3);
+}
+
+static inline unsigned int
+xfs_rename_log_count(
+	struct xfs_mount	*mp,
+	struct xfs_trans_resv	*resp)
+{
+	/* One for the rename, one more for freeing blocks */
+	unsigned int		ret = XFS_RENAME_LOG_COUNT;
+
+	/*
+	 * Pre-reserve enough log reservation to handle the transaction
+	 * rolling needed to remove or add one parent pointer.
+	 */
+	if (xfs_has_parent(mp))
+		ret += max(resp->tr_attrsetm.tr_logcount,
+			   resp->tr_attrrm.tr_logcount);
+
+	return ret;
 }
 
 /*
@@ -461,6 +684,23 @@ xfs_calc_iunlink_remove_reservation(
 	       2 * M_IGEO(mp)->inode_cluster_size;
 }
 
+static inline unsigned int
+xfs_link_log_count(
+	struct xfs_mount	*mp,
+	struct xfs_trans_resv	*resp)
+{
+	unsigned int		ret = XFS_LINK_LOG_COUNT;
+
+	/*
+	 * Pre-reserve enough log reservation to handle the transaction
+	 * rolling needed to add one parent pointer.
+	 */
+	if (xfs_has_parent(mp))
+		ret += resp->tr_attrsetm.tr_logcount;
+
+	return ret;
+}
+
 /*
  * For creating a link to an inode:
  *    the parent directory inode: inode size
@@ -477,14 +717,21 @@ STATIC uint
 xfs_calc_link_reservation(
 	struct xfs_mount	*mp)
 {
-	return XFS_DQUOT_LOGRES(mp) +
-		xfs_calc_iunlink_remove_reservation(mp) +
-		max((xfs_calc_inode_res(mp, 2) +
-		     xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp),
-				      XFS_FSB_TO_B(mp, 1))),
-		    (xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
-		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
-				      XFS_FSB_TO_B(mp, 1))));
+	unsigned int		overhead = XFS_DQUOT_LOGRES;
+	struct xfs_trans_resv	*resp = M_RES(mp);
+	unsigned int		t1, t2, t3 = 0;
+
+	overhead += xfs_calc_iunlink_remove_reservation(mp);
+	t1 = xfs_calc_inode_res(mp, 2) +
+	     xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp), XFS_FSB_TO_B(mp, 1));
+	t2 = xfs_calc_finish_efi_reservation(mp, 1);
+
+	if (xfs_has_parent(mp)) {
+		t3 = resp->tr_attrsetm.tr_logres;
+		overhead += xfs_calc_pptr_link_overhead();
+	}
+
+	return overhead + max3(t1, t2, t3);
 }
 
 /*
@@ -499,6 +746,23 @@ xfs_calc_iunlink_add_reservation(xfs_mount_t *mp)
 			M_IGEO(mp)->inode_cluster_size;
 }
 
+static inline unsigned int
+xfs_remove_log_count(
+	struct xfs_mount	*mp,
+	struct xfs_trans_resv	*resp)
+{
+	unsigned int		ret = XFS_REMOVE_LOG_COUNT;
+
+	/*
+	 * Pre-reserve enough log reservation to handle the transaction
+	 * rolling needed to add one parent pointer.
+	 */
+	if (xfs_has_parent(mp))
+		ret += resp->tr_attrrm.tr_logcount;
+
+	return ret;
+}
+
 /*
  * For removing a directory entry we can modify:
  *    the parent directory inode: inode size
@@ -515,14 +779,22 @@ STATIC uint
 xfs_calc_remove_reservation(
 	struct xfs_mount	*mp)
 {
-	return XFS_DQUOT_LOGRES(mp) +
-		xfs_calc_iunlink_add_reservation(mp) +
-		max((xfs_calc_inode_res(mp, 2) +
-		     xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp),
-				      XFS_FSB_TO_B(mp, 1))),
-		    (xfs_calc_buf_res(4, mp->m_sb.sb_sectsize) +
-		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2),
-				      XFS_FSB_TO_B(mp, 1))));
+	unsigned int            overhead = XFS_DQUOT_LOGRES;
+	struct xfs_trans_resv   *resp = M_RES(mp);
+	unsigned int            t1, t2, t3 = 0;
+
+	overhead += xfs_calc_iunlink_add_reservation(mp);
+
+	t1 = xfs_calc_inode_res(mp, 2) +
+	     xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp), XFS_FSB_TO_B(mp, 1));
+	t2 = xfs_calc_finish_efi_reservation(mp, 2);
+
+	if (xfs_has_parent(mp)) {
+		t3 = resp->tr_attrrm.tr_logres;
+		overhead += xfs_calc_pptr_unlink_overhead();
+	}
+
+	return overhead + max3(t1, t2, t3);
 }
 
 /*
@@ -571,24 +843,69 @@ xfs_calc_icreate_resv_alloc(
 		xfs_calc_finobt_res(mp);
 }
 
+static inline unsigned int
+xfs_icreate_log_count(
+	struct xfs_mount	*mp,
+	struct xfs_trans_resv	*resp)
+{
+	unsigned int		ret = XFS_CREATE_LOG_COUNT;
+
+	/*
+	 * Pre-reserve enough log reservation to handle the transaction
+	 * rolling needed to add one parent pointer.
+	 */
+	if (xfs_has_parent(mp))
+		ret += resp->tr_attrsetm.tr_logcount;
+
+	return ret;
+}
+
 STATIC uint
-xfs_calc_icreate_reservation(xfs_mount_t *mp)
+xfs_calc_icreate_reservation(
+	struct xfs_mount	*mp)
 {
-	return XFS_DQUOT_LOGRES(mp) +
-		max(xfs_calc_icreate_resv_alloc(mp),
-		    xfs_calc_create_resv_modify(mp));
+	struct xfs_trans_resv	*resp = M_RES(mp);
+	unsigned int		overhead = XFS_DQUOT_LOGRES;
+	unsigned int		t1, t2, t3 = 0;
+
+	t1 = xfs_calc_icreate_resv_alloc(mp);
+	t2 = xfs_calc_create_resv_modify(mp);
+
+	if (xfs_has_parent(mp)) {
+		t3 = resp->tr_attrsetm.tr_logres;
+		overhead += xfs_calc_pptr_link_overhead();
+	}
+
+	return overhead + max3(t1, t2, t3);
 }
 
 STATIC uint
 xfs_calc_create_tmpfile_reservation(
 	struct xfs_mount        *mp)
 {
-	uint	res = XFS_DQUOT_LOGRES(mp);
+	uint	res = XFS_DQUOT_LOGRES;
 
 	res += xfs_calc_icreate_resv_alloc(mp);
 	return res + xfs_calc_iunlink_add_reservation(mp);
 }
 
+static inline unsigned int
+xfs_mkdir_log_count(
+	struct xfs_mount	*mp,
+	struct xfs_trans_resv	*resp)
+{
+	unsigned int		ret = XFS_MKDIR_LOG_COUNT;
+
+	/*
+	 * Pre-reserve enough log reservation to handle the transaction
+	 * rolling needed to add one parent pointer.
+	 */
+	if (xfs_has_parent(mp))
+		ret += resp->tr_attrsetm.tr_logcount;
+
+	return ret;
+}
+
 /*
  * Making a new directory is the same as creating a new file.
  */
@@ -599,6 +916,22 @@ xfs_calc_mkdir_reservation(
 	return xfs_calc_icreate_reservation(mp);
 }
 
+static inline unsigned int
+xfs_symlink_log_count(
+	struct xfs_mount	*mp,
+	struct xfs_trans_resv	*resp)
+{
+	unsigned int		ret = XFS_SYMLINK_LOG_COUNT;
+
+	/*
+	 * Pre-reserve enough log reservation to handle the transaction
+	 * rolling needed to add one parent pointer.
+	 */
+	if (xfs_has_parent(mp))
+		ret += resp->tr_attrsetm.tr_logcount;
+
+	return ret;
+}
 
 /*
  * Making a new symplink is the same as creating a new file, but
@@ -632,7 +965,7 @@ STATIC uint
 xfs_calc_ifree_reservation(
 	struct xfs_mount	*mp)
 {
-	return XFS_DQUOT_LOGRES(mp) +
+	return XFS_DQUOT_LOGRES +
 		xfs_calc_inode_res(mp, 1) +
 		xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
 		xfs_calc_iunlink_remove_reservation(mp) +
@@ -649,7 +982,7 @@ STATIC uint
 xfs_calc_ichange_reservation(
 	struct xfs_mount	*mp)
 {
-	return XFS_DQUOT_LOGRES(mp) +
+	return XFS_DQUOT_LOGRES +
 		xfs_calc_inode_res(mp, 1) +
 		xfs_calc_buf_res(1, mp->m_sb.sb_sectsize);
 
@@ -721,7 +1054,7 @@ xfs_calc_growrtfree_reservation(
 	return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
 		xfs_calc_inode_res(mp, 2) +
 		xfs_calc_buf_res(1, mp->m_sb.sb_blocksize) +
-		xfs_calc_buf_res(1, mp->m_rsumsize);
+		xfs_calc_buf_res(1, XFS_FSB_TO_B(mp, mp->m_rsumblocks));
 }
 
 /*
@@ -758,7 +1091,7 @@ STATIC uint
 xfs_calc_addafork_reservation(
 	struct xfs_mount	*mp)
 {
-	return XFS_DQUOT_LOGRES(mp) +
+	return XFS_DQUOT_LOGRES +
 		xfs_calc_inode_res(mp, 1) +
 		xfs_calc_buf_res(2, mp->m_sb.sb_sectsize) +
 		xfs_calc_buf_res(1, mp->m_dir_geo->blksize) +
@@ -806,7 +1139,7 @@ STATIC uint
 xfs_calc_attrsetm_reservation(
 	struct xfs_mount	*mp)
 {
-	return XFS_DQUOT_LOGRES(mp) +
+	return XFS_DQUOT_LOGRES +
 		xfs_calc_inode_res(mp, 1) +
 		xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
 		xfs_calc_buf_res(XFS_DA_NODE_MAXDEPTH, XFS_FSB_TO_B(mp, 1));
@@ -846,7 +1179,7 @@ STATIC uint
 xfs_calc_attrrm_reservation(
 	struct xfs_mount	*mp)
 {
-	return XFS_DQUOT_LOGRES(mp) +
+	return XFS_DQUOT_LOGRES +
 		max((xfs_calc_inode_res(mp, 1) +
 		     xfs_calc_buf_res(XFS_DA_NODE_MAXDEPTH,
 				      XFS_FSB_TO_B(mp, 1)) +
@@ -911,54 +1244,85 @@ xfs_calc_sb_reservation(
 	return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize);
 }
 
-void
-xfs_trans_resv_calc(
+/*
+ * Namespace reservations.
+ *
+ * These get tricky when parent pointers are enabled as we have attribute
+ * modifications occurring from within these transactions. Rather than confuse
+ * each of these reservation calculations with the conditional attribute
+ * reservations, add them here in a clear and concise manner. This requires that
+ * the attribute reservations have already been calculated.
+ *
+ * Note that we only include the static attribute reservation here; the runtime
+ * reservation will have to be modified by the size of the attributes being
+ * added/removed/modified. See the comments on the attribute reservation
+ * calculations for more details.
+ */
+STATIC void
+xfs_calc_namespace_reservations(
 	struct xfs_mount	*mp,
 	struct xfs_trans_resv	*resp)
 {
-	int			logcount_adj = 0;
-
-	/*
-	 * The following transactions are logged in physical format and
-	 * require a permanent reservation on space.
-	 */
-	resp->tr_write.tr_logres = xfs_calc_write_reservation(mp, false);
-	resp->tr_write.tr_logcount = XFS_WRITE_LOG_COUNT;
-	resp->tr_write.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
-
-	resp->tr_itruncate.tr_logres = xfs_calc_itruncate_reservation(mp, false);
-	resp->tr_itruncate.tr_logcount = XFS_ITRUNCATE_LOG_COUNT;
-	resp->tr_itruncate.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+	ASSERT(resp->tr_attrsetm.tr_logres > 0);
 
 	resp->tr_rename.tr_logres = xfs_calc_rename_reservation(mp);
-	resp->tr_rename.tr_logcount = XFS_RENAME_LOG_COUNT;
+	resp->tr_rename.tr_logcount = xfs_rename_log_count(mp, resp);
 	resp->tr_rename.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
 
 	resp->tr_link.tr_logres = xfs_calc_link_reservation(mp);
-	resp->tr_link.tr_logcount = XFS_LINK_LOG_COUNT;
+	resp->tr_link.tr_logcount = xfs_link_log_count(mp, resp);
 	resp->tr_link.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
 
 	resp->tr_remove.tr_logres = xfs_calc_remove_reservation(mp);
-	resp->tr_remove.tr_logcount = XFS_REMOVE_LOG_COUNT;
+	resp->tr_remove.tr_logcount = xfs_remove_log_count(mp, resp);
 	resp->tr_remove.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
 
 	resp->tr_symlink.tr_logres = xfs_calc_symlink_reservation(mp);
-	resp->tr_symlink.tr_logcount = XFS_SYMLINK_LOG_COUNT;
+	resp->tr_symlink.tr_logcount = xfs_symlink_log_count(mp, resp);
 	resp->tr_symlink.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
 
 	resp->tr_create.tr_logres = xfs_calc_icreate_reservation(mp);
-	resp->tr_create.tr_logcount = XFS_CREATE_LOG_COUNT;
+	resp->tr_create.tr_logcount = xfs_icreate_log_count(mp, resp);
 	resp->tr_create.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
 
+	resp->tr_mkdir.tr_logres = xfs_calc_mkdir_reservation(mp);
+	resp->tr_mkdir.tr_logcount = xfs_mkdir_log_count(mp, resp);
+	resp->tr_mkdir.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+}
+
+STATIC void
+xfs_calc_default_atomic_ioend_reservation(
+	struct xfs_mount	*mp,
+	struct xfs_trans_resv	*resp)
+{
+	/* Pick a default that will scale reasonably for the log size. */
+	resp->tr_atomic_ioend = resp->tr_itruncate;
+}
+
+void
+xfs_trans_resv_calc(
+	struct xfs_mount	*mp,
+	struct xfs_trans_resv	*resp)
+{
+	int			logcount_adj = 0;
+
+	/*
+	 * The following transactions are logged in physical format and
+	 * require a permanent reservation on space.
+	 */
+	resp->tr_write.tr_logres = xfs_calc_write_reservation(mp, false);
+	resp->tr_write.tr_logcount = XFS_WRITE_LOG_COUNT;
+	resp->tr_write.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+	resp->tr_itruncate.tr_logres = xfs_calc_itruncate_reservation(mp, false);
+	resp->tr_itruncate.tr_logcount = XFS_ITRUNCATE_LOG_COUNT;
+	resp->tr_itruncate.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
 	resp->tr_create_tmpfile.tr_logres =
 			xfs_calc_create_tmpfile_reservation(mp);
 	resp->tr_create_tmpfile.tr_logcount = XFS_CREATE_TMPFILE_LOG_COUNT;
 	resp->tr_create_tmpfile.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
 
-	resp->tr_mkdir.tr_logres = xfs_calc_mkdir_reservation(mp);
-	resp->tr_mkdir.tr_logcount = XFS_MKDIR_LOG_COUNT;
-	resp->tr_mkdir.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
-
 	resp->tr_ifree.tr_logres = xfs_calc_ifree_reservation(mp);
 	resp->tr_ifree.tr_logcount = XFS_INACTIVE_LOG_COUNT;
 	resp->tr_ifree.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
@@ -988,6 +1352,8 @@ xfs_trans_resv_calc(
 	resp->tr_qm_dqalloc.tr_logcount = XFS_WRITE_LOG_COUNT;
 	resp->tr_qm_dqalloc.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
 
+	xfs_calc_namespace_reservations(mp, resp);
+
 	/*
 	 * The following transactions are logged in logical format with
 	 * a default log count.
@@ -1027,4 +1393,167 @@ xfs_trans_resv_calc(
 	resp->tr_itruncate.tr_logcount += logcount_adj;
 	resp->tr_write.tr_logcount += logcount_adj;
 	resp->tr_qm_dqalloc.tr_logcount += logcount_adj;
+
+	/*
+	 * Now that we've finished computing the static reservations, we can
+	 * compute the dynamic reservation for atomic writes.
+	 */
+	xfs_calc_default_atomic_ioend_reservation(mp, resp);
+}
+
+/*
+ * Return the per-extent and fixed transaction reservation sizes needed to
+ * complete an atomic write.
+ */
+STATIC unsigned int
+xfs_calc_atomic_write_ioend_geometry(
+	struct xfs_mount	*mp,
+	unsigned int		*step_size)
+{
+	const unsigned int	efi = xfs_efi_log_space(1);
+	const unsigned int	efd = xfs_efd_log_space(1);
+	const unsigned int	rui = xfs_rui_log_space(1);
+	const unsigned int	rud = xfs_rud_log_space();
+	const unsigned int	cui = xfs_cui_log_space(1);
+	const unsigned int	cud = xfs_cud_log_space();
+	const unsigned int	bui = xfs_bui_log_space(1);
+	const unsigned int	bud = xfs_bud_log_space();
+
+	/*
+	 * Maximum overhead to complete an atomic write ioend in software:
+	 * remove data fork extent + remove cow fork extent + map extent into
+	 * data fork.
+	 *
+	 * tx0: Creates a BUI and a CUI and that's all it needs.
+	 *
+	 * tx1: Roll to finish the BUI.  Need space for the BUD, an RUI, and
+	 * enough space to relog the CUI (== CUI + CUD).
+	 *
+	 * tx2: Roll again to finish the RUI.  Need space for the RUD and space
+	 * to relog the CUI.
+	 *
+	 * tx3: Roll again, need space for the CUD and possibly a new EFI.
+	 *
+	 * tx4: Roll again, need space for an EFD.
+	 *
+	 * If the extent referenced by the pair of BUI/CUI items is not the one
+	 * being currently processed, then we need to reserve space to relog
+	 * both items.
+	 */
+	const unsigned int	tx0 = bui + cui;
+	const unsigned int	tx1 = bud + rui + cui + cud;
+	const unsigned int	tx2 = rud + cui + cud;
+	const unsigned int	tx3 = cud + efi;
+	const unsigned int	tx4 = efd;
+	const unsigned int	relog = bui + bud + cui + cud;
+
+	const unsigned int	per_intent = max(max3(tx0, tx1, tx2),
+						 max3(tx3, tx4, relog));
+
+	/* Overhead to finish one step of each intent item type */
+	const unsigned int	f1 = xfs_calc_finish_efi_reservation(mp, 1);
+	const unsigned int	f2 = xfs_calc_finish_rui_reservation(mp, 1);
+	const unsigned int	f3 = xfs_calc_finish_cui_reservation(mp, 1);
+	const unsigned int	f4 = xfs_calc_finish_bui_reservation(mp, 1);
+
+	/* We only finish one item per transaction in a chain */
+	*step_size = max(f4, max3(f1, f2, f3));
+
+	return per_intent;
+}
+
+/*
+ * Compute the maximum size (in fsblocks) of atomic writes that we can complete
+ * given the existing log reservations.
+ */
+xfs_extlen_t
+xfs_calc_max_atomic_write_fsblocks(
+	struct xfs_mount		*mp)
+{
+	const struct xfs_trans_res	*resv = &M_RES(mp)->tr_atomic_ioend;
+	unsigned int			per_intent = 0;
+	unsigned int			step_size = 0;
+	unsigned int			ret = 0;
+
+	if (resv->tr_logres > 0) {
+		per_intent = xfs_calc_atomic_write_ioend_geometry(mp,
+				&step_size);
+
+		if (resv->tr_logres >= step_size)
+			ret = (resv->tr_logres - step_size) / per_intent;
+	}
+
+	trace_xfs_calc_max_atomic_write_fsblocks(mp, per_intent, step_size,
+			resv->tr_logres, ret);
+
+	return ret;
+}
+
+/*
+ * Compute the log blocks and transaction reservation needed to complete an
+ * atomic write of a given number of blocks.  Worst case, each block requires
+ * separate handling.  A return value of 0 means something went wrong.
+ */
+xfs_extlen_t
+xfs_calc_atomic_write_log_geometry(
+	struct xfs_mount	*mp,
+	xfs_extlen_t		blockcount,
+	unsigned int		*new_logres)
+{
+	struct xfs_trans_res	*curr_res = &M_RES(mp)->tr_atomic_ioend;
+	uint			old_logres = curr_res->tr_logres;
+	unsigned int		per_intent, step_size;
+	unsigned int		logres;
+	xfs_extlen_t		min_logblocks;
+
+	ASSERT(blockcount > 0);
+
+	xfs_calc_default_atomic_ioend_reservation(mp, M_RES(mp));
+
+	per_intent = xfs_calc_atomic_write_ioend_geometry(mp, &step_size);
+
+	/* Check for overflows */
+	if (check_mul_overflow(blockcount, per_intent, &logres) ||
+	    check_add_overflow(logres, step_size, &logres))
+		return 0;
+
+	curr_res->tr_logres = logres;
+	min_logblocks = xfs_log_calc_minimum_size(mp);
+	curr_res->tr_logres = old_logres;
+
+	trace_xfs_calc_max_atomic_write_log_geometry(mp, per_intent, step_size,
+			blockcount, min_logblocks, logres);
+
+	*new_logres = logres;
+	return min_logblocks;
+}
+
+/*
+ * Compute the transaction reservation needed to complete an out of place
+ * atomic write of a given number of blocks.
+ */
+int
+xfs_calc_atomic_write_reservation(
+	struct xfs_mount	*mp,
+	xfs_extlen_t		blockcount)
+{
+	unsigned int		new_logres;
+	xfs_extlen_t		min_logblocks;
+
+	/*
+	 * If the caller doesn't ask for a specific atomic write size, then
+	 * use the defaults.
+	 */
+	if (blockcount == 0) {
+		xfs_calc_default_atomic_ioend_reservation(mp, M_RES(mp));
+		return 0;
+	}
+
+	min_logblocks = xfs_calc_atomic_write_log_geometry(mp, blockcount,
+			&new_logres);
+	if (!min_logblocks || min_logblocks > mp->m_sb.sb_logblocks)
+		return -EINVAL;
+
+	M_RES(mp)->tr_atomic_ioend.tr_logres = new_logres;
+	return 0;
 }