- int error;
+ struct xfs_da_args *args = dac->da_args;
+ struct xfs_da_state **state = &dac->da_state;
+ int error;
error = xfs_attr_node_hasname(args, state);
if (error != -EEXIST)
@@ -1203,13 +1267,16 @@ int xfs_attr_node_removename_setup(
}
STATIC int
-xfs_attr_node_remove_rmt(
- struct xfs_da_args *args,
- struct xfs_da_state *state)
+xfs_attr_node_remove_rmt (
+ struct xfs_delattr_context *dac,
+ struct xfs_da_state *state)
{
- int error = 0;
+ int error = 0;
- error = xfs_attr_rmtval_remove(args);
+ /*
+ * May return -EAGAIN to request that the caller recall this function
+ */
+ error = __xfs_attr_rmtval_remove(dac);
if (error)
return error;
@@ -1240,28 +1307,34 @@ xfs_attr_node_remove_cleanup(
}
/*
- * Remove a name from a B-tree attribute list.
+ * Step through removeing a name from a B-tree attribute list.
*
* This will involve walking down the Btree, and may involve joining
* leaf nodes and even joining intermediate nodes up to and including
* the root node (a special case of an intermediate node).
+ *
+ * This routine is meant to function as either an inline or delayed operation,
+ * and may return -EAGAIN when the transaction needs to be rolled. Calling
+ * functions will need to handle this, and recall the function until a
+ * successful error code is returned.
*/
STATIC int
xfs_attr_node_remove_step(
- struct xfs_da_args *args,
- struct xfs_da_state *state)
+ struct xfs_delattr_context *dac)
{
- int error;
- struct xfs_inode *dp = args->dp;
-
-
+ struct xfs_da_args *args = dac->da_args;
+ struct xfs_da_state *state = dac->da_state;
+ int error = 0;
/*
* If there is an out-of-line value, de-allocate the blocks.
* This is done before we remove the attribute so that we don't
* overflow the maximum size of a transaction and/or hit a deadlock.
*/
if (args->rmtblkno > 0) {
- error = xfs_attr_node_remove_rmt(args, state);
+ /*
+ * May return -EAGAIN. Remove blocks until args->rmtblkno == 0
+ */
+ error = xfs_attr_node_remove_rmt(dac, state);
if (error)
return error;
}
@@ -1274,51 +1347,74 @@ xfs_attr_node_remove_step(
*
* This routine will find the blocks of the name to remove, remove them and
* shrink the tree if needed.
+ *
+ * This routine is meant to function as either an inline or delayed operation,
+ * and may return -EAGAIN when the transaction needs to be rolled. Calling
+ * functions will need to handle this, and recall the function until a
+ * successful error code is returned.
*/
STATIC int
-xfs_attr_node_removename(
- struct xfs_da_args *args)
+xfs_attr_node_removename_iter(
+ struct xfs_delattr_context *dac)
{
- struct xfs_da_state *state = NULL;
- int retval, error;
- struct xfs_inode *dp = args->dp;
+ struct xfs_da_args *args = dac->da_args;
+ struct xfs_da_state *state = NULL;
+ int retval, error;
+ struct xfs_inode *dp = args->dp;
trace_xfs_attr_node_removename(args);
- error = xfs_attr_node_removename_setup(args, &state);
- if (error)
- goto out;
+ if (!dac->da_state) {
+ error = xfs_attr_node_removename_setup(dac);
+ if (error)
+ goto out;
+ }
+ state = dac->da_state;
- error = xfs_attr_node_remove_step(args, state);
- if (error)
- goto out;
+ switch (dac->dela_state) {
+ case XFS_DAS_UNINIT:
+ /*
+ * repeatedly remove remote blocks, remove the entry and join.
+ * returns -EAGAIN or 0 for completion of the step.
+ */
+ error = xfs_attr_node_remove_step(dac);
+ if (error)
+ break;
- retval = xfs_attr_node_remove_cleanup(args, state);
+ retval = xfs_attr_node_remove_cleanup(args, state);
- /*
- * Check to see if the tree needs to be collapsed.
- */
- if (retval && (state->path.active > 1)) {
- error = xfs_da3_join(state);
- if (error)
- return error;
- error = xfs_defer_finish(&args->trans);
- if (error)
- return error;
/*
- * Commit the Btree join operation and start a new trans.
+ * Check to see if the tree needs to be collapsed. Set the flag
+ * to indicate that the calling function needs to move the
+ * shrink operation
*/
- error = xfs_trans_roll_inode(&args->trans, dp);
- if (error)
- return error;
- }
+ if (retval && (state->path.active > 1)) {
+ error = xfs_da3_join(state);
+ if (error)
+ return error;
- /*
- * If the result is small enough, push it all into the inode.
- */
- if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
- error = xfs_attr_node_shrink(args, state);
+ dac->flags |= XFS_DAC_DEFER_FINISH;
+ dac->dela_state = XFS_DAS_RM_SHRINK;
+ return -EAGAIN;
+ }
+
+ /* fallthrough */
+ case XFS_DAS_RM_SHRINK:
+ /*
+ * If the result is small enough, push it all into the inode.
+ */
+ if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
+ error = xfs_attr_node_shrink(args, state);
+
+ break;
+ default:
+ ASSERT(0);
+ error = -EINVAL;
+ goto out;
+ }
+ if (error == -EAGAIN)
+ return error;
out:
if (state)
xfs_da_state_free(state);
diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
index 3e97a93..3154ef4 100644
--- a/fs/xfs/libxfs/xfs_attr.h
+++ b/fs/xfs/libxfs/xfs_attr.h
@@ -74,6 +74,102 @@ struct xfs_attr_list_context {
};
+/*
+ * ========================================================================
+ * Structure used to pass context around among the delayed routines.
+ * ========================================================================
+ */
+
+/*
+ * Below is a state machine diagram for attr remove operations. The XFS_DAS_*
+ * states indicate places where the function would return -EAGAIN, and then
+ * immediately resume from after being recalled by the calling function. States
+ * marked as a "subroutine state" indicate that they belong to a subroutine, and
+ * so the calling function needs to pass them back to that subroutine to allow
+ * it to finish where it left off. But they otherwise do not have a role in the
+ * calling function other than just passing through.
+ *
+ * xfs_attr_remove_iter()
+ * │
+ * v
+ * found attr blks? ───n──┐
+ * │ v
+ * │ find and invalidate
+ * y the blocks. mark
+ * │ attr incomplete
+ * ├────────────────┘
+ * │
+ * v
+ * remove a block with
+ * xfs_attr_node_remove_step <────┐
+ * │ │
+ * v │
+ * still have blks ──y──> return -EAGAIN.
+ * to remove? re-enter with one
+ * │ less blk to remove
+ * n
+ * │
+ * v
+ * remove leaf and
+ * update hash with
+ * xfs_attr_node_remove_cleanup
+ * │
+ * v
+ * need to
+ * shrink tree? ─n─┐
+ * │ │
+ * y │
+ * │ │
+ * v │
+ * join leaf │
+ * │ │
+ * v │
+ * XFS_DAS_RM_SHRINK │
+ * │ │
+ * v │
+ * do the shrink │
+ * │ │
+ * v │
+ * free state <──┘
+ * │
+ * v
+ * done
+ *
+ */
+
+/*
+ * Enum values for xfs_delattr_context.da_state
+ *
+ * These values are used by delayed attribute operations to keep track of where
+ * they were before they returned -EAGAIN. A return code of -EAGAIN signals the
+ * calling function to roll the transaction, and then recall the subroutine to
+ * finish the operation. The enum is then used by the subroutine to jump back
+ * to where it was and resume executing where it left off.
+ */
+enum xfs_delattr_state {
+ XFS_DAS_UNINIT = 0, /* No state has been set yet */
+ XFS_DAS_RM_SHRINK, /* We are shrinking the tree */
+};
+
+/*
+ * Defines for xfs_delattr_context.flags
+ */
+#define XFS_DAC_DEFER_FINISH 0x01 /* finish the transaction */
+
+/*
+ * Context used for keeping track of delayed attribute operations
+ */
+struct xfs_delattr_context {
+ struct xfs_da_args *da_args;
+
+ /* Used in xfs_attr_node_removename to roll through removing blocks */
+ struct xfs_da_state *da_state;
+
+ /* Used to keep track of current state of delayed operation */
+ unsigned int flags;
+ enum xfs_delattr_state dela_state;
+};
+
/*========================================================================
* Function prototypes for the kernel.
*========================================================================*/
@@ -91,6 +187,10 @@ int xfs_attr_set(struct xfs_da_args *args);
int xfs_attr_set_args(struct xfs_da_args *args);
int xfs_has_attr(struct xfs_da_args *args);
int xfs_attr_remove_args(struct xfs_da_args *args);
+int xfs_attr_remove_iter(struct xfs_delattr_context *dac);
+int xfs_attr_trans_roll(struct xfs_delattr_context *dac);
bool xfs_attr_namecheck(const void *name, size_t length);
+void xfs_delattr_context_init(struct xfs_delattr_context *dac,
+ struct xfs_da_args *args);
#endif /* __XFS_ATTR_H__ */
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index d6ef69a..3780141 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -19,8 +19,8 @@
#include "xfs_bmap_btree.h"
#include "xfs_bmap.h"
#include "xfs_attr_sf.h"
-#include "xfs_attr_remote.h"
#include "xfs_attr.h"
+#include "xfs_attr_remote.h"
#include "xfs_attr_leaf.h"
#include "xfs_error.h"
#include "xfs_trace.h"
diff --git a/fs/xfs/libxfs/xfs_attr_remote.c b/fs/xfs/libxfs/xfs_attr_remote.c
index 48d8e9c..f09820c 100644
--- a/fs/xfs/libxfs/xfs_attr_remote.c
+++ b/fs/xfs/libxfs/xfs_attr_remote.c
@@ -674,10 +674,12 @@ xfs_attr_rmtval_invalidate(
*/
int
xfs_attr_rmtval_remove(
- struct xfs_da_args *args)
+ struct xfs_da_args *args)
{
- int error;
- int retval;
+ int error;
+ struct xfs_delattr_context dac = {
+ .da_args = args,
+ };
trace_xfs_attr_rmtval_remove(args);
@@ -685,31 +687,29 @@ xfs_attr_rmtval_remove(
* Keep de-allocating extents until the remote-value region is gone.
*/
do {
- retval = __xfs_attr_rmtval_remove(args);
- if (retval && retval != -EAGAIN)
- return retval;
+ error = __xfs_attr_rmtval_remove(&dac);
+ if (error != -EAGAIN)
+ break;
- /*
- * Close out trans and start the next one in the chain.
- */
- error = xfs_trans_roll_inode(&args->trans, args->dp);
+ error = xfs_attr_trans_roll(&dac);
if (error)
return error;
- } while (retval == -EAGAIN);
+ } while (true);
- return 0;
+ return error;
}
/*
* Remove the value associated with an attribute by deleting the out-of-line
- * buffer that it is stored on. Returns EAGAIN for the caller to refresh the
+ * buffer that it is stored on. Returns -EAGAIN for the caller to refresh the
* transaction and re-call the function
*/
int
__xfs_attr_rmtval_remove(
- struct xfs_da_args *args)
+ struct xfs_delattr_context *dac)
{
- int error, done;
+ struct xfs_da_args *args = dac->da_args;
+ int error, done;
/*
* Unmap value blocks for this attr.
@@ -719,12 +719,20 @@ __xfs_attr_rmtval_remove(
if (error)
return error;
- error = xfs_defer_finish(&args->trans);
- if (error)
- return error;
-
- if (!done)
+ /*
+ * We dont need an explicit state here to pick up where we left off. We
+ * can figure it out using the !done return code. Calling function only
+ * needs to keep recalling this routine until we indicate to stop by
+ * returning anything other than -EAGAIN. The actual value of
+ * attr->xattri_dela_state may be some value reminicent of the calling
+ * function, but it's value is irrelevant with in the context of this
+ * function. Once we are done here, the next state is set as needed
+ * by the parent
+ */
+ if (!done) {
+ dac->flags |= XFS_DAC_DEFER_FINISH;
return -EAGAIN;
+ }
return error;
}
diff --git a/fs/xfs/libxfs/xfs_attr_remote.h b/fs/xfs/libxfs/xfs_attr_remote.h
index 9eee615..002fd30 100644
--- a/fs/xfs/libxfs/xfs_attr_remote.h
+++ b/fs/xfs/libxfs/xfs_attr_remote.h
@@ -14,5 +14,5 @@ int xfs_attr_rmtval_remove(struct xfs_da_args *args);
int xfs_attr_rmtval_stale(struct xfs_inode *ip, struct xfs_bmbt_irec *map,
xfs_buf_flags_t incore_flags);
int xfs_attr_rmtval_invalidate(struct xfs_da_args *args);
-int __xfs_attr_rmtval_remove(struct xfs_da_args *args);
+int __xfs_attr_rmtval_remove(struct xfs_delattr_context *dac);
#endif /* __XFS_ATTR_REMOTE_H__ */
diff --git a/fs/xfs/xfs_attr_inactive.c b/fs/xfs/xfs_attr_inactive.c
index bfad669..aaa7e66 100644
--- a/fs/xfs/xfs_attr_inactive.c
+++ b/fs/xfs/xfs_attr_inactive.c
@@ -15,10 +15,10 @@
#include "xfs_da_format.h"
#include "xfs_da_btree.h"
#include "xfs_inode.h"
+#include "xfs_attr.h"
#include "xfs_attr_remote.h"
#include "xfs_trans.h"
#include "xfs_bmap.h"
-#include "xfs_attr.h"
#include "xfs_attr_leaf.h"
#include "xfs_quota.h"
#include "xfs_dir2.h"
