diff options
author | 2017-07-26 11:22:26 -0400 | |
---|---|---|
committer | 2017-07-30 08:08:31 -0700 | |
commit | ec57d6e63c070ddba1d00ca91fd852e947e4ff5d (patch) | |
tree | 157fd0cb78672db7af6c25268c91301c22a9b793 /drivers/staging/lustre/lustre/ldlm/interval_tree.c | |
parent | staging: lustre: ptlrpc: no need to reassign mbits for replay (diff) | |
download | linux-dev-ec57d6e63c070ddba1d00ca91fd852e947e4ff5d.tar.xz linux-dev-ec57d6e63c070ddba1d00ca91fd852e947e4ff5d.zip |
staging: lustre: ldlm: restore interval_iterate_reverse function
Earlier the function interval_iterate_reverse function was
removed since it wasn't used by anyone. Now it is being
restored since it will be used by a future patch.
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/lustre/lustre/ldlm/interval_tree.c')
-rw-r--r-- | drivers/staging/lustre/lustre/ldlm/interval_tree.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lustre/ldlm/interval_tree.c b/drivers/staging/lustre/lustre/ldlm/interval_tree.c index e1069021420d..5bebd9a361ee 100644 --- a/drivers/staging/lustre/lustre/ldlm/interval_tree.c +++ b/drivers/staging/lustre/lustre/ldlm/interval_tree.c @@ -110,6 +110,15 @@ static struct interval_node *interval_first(struct interval_node *node) return node; } +static struct interval_node *interval_last(struct interval_node *node) +{ + if (!node) + return NULL; + while (node->in_right) + node = node->in_right; + return node; +} + static struct interval_node *interval_next(struct interval_node *node) { if (!node) @@ -121,6 +130,37 @@ static struct interval_node *interval_next(struct interval_node *node) return node->in_parent; } +static struct interval_node *interval_prev(struct interval_node *node) +{ + if (!node) + return NULL; + + if (node->in_left) + return interval_last(node->in_left); + + while (node->in_parent && node_is_left_child(node)) + node = node->in_parent; + + return node->in_parent; +} + +enum interval_iter interval_iterate_reverse(struct interval_node *root, + interval_callback_t func, + void *data) +{ + enum interval_iter rc = INTERVAL_ITER_CONT; + struct interval_node *node; + + for (node = interval_last(root); node; node = interval_prev(node)) { + rc = func(node, data); + if (rc == INTERVAL_ITER_STOP) + break; + } + + return rc; +} +EXPORT_SYMBOL(interval_iterate_reverse); + static void __rotate_change_maxhigh(struct interval_node *node, struct interval_node *rotate) { |