[PATCH v4 07/11] VAS: Define helpers to alloc/free windows

Sukadev Bhattiprolu
2017-03-31T05:15:21Z

Define helpers to allocate/free VAS window objects. These will
be used in follow-on patches when opening/closing windows.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
---
arch/powerpc/platforms/powernv/vas-window.c | 63 ++++++++++++++++++++++++++++-
1 file changed, 62 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 5ddcb63..0c178fe 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -120,7 +120,7 @@ static void unmap_wc_mmio_bars(struct vas_window *window)
* OS/User Window Context (UWC) MMIO Base Address Region for the given window.
* Map these bus addresses and save the mapped kernel addresses in @window.
*/
-int map_wc_mmio_bars(struct vas_window *window)
+static int map_wc_mmio_bars(struct vas_window *window)
{
int len;
uint64_t start;
@@ -437,6 +437,67 @@ int init_winctx_regs(struct vas_window *window, struct vas_winctx *winctx)
return 0;
}

+DEFINE_SPINLOCK(vas_ida_lock);
+
+void vas_release_window_id(struct ida *ida, int winid)
+{
+ spin_lock(&vas_ida_lock);
+ ida_remove(ida, winid);
+ spin_unlock(&vas_ida_lock);
+}
+
+int vas_assign_window_id(struct ida *ida)
+{
+ int rc, winid;
+
+ rc = ida_pre_get(ida, GFP_KERNEL);
+ if (!rc)
+ return -EAGAIN;
+
+ spin_lock(&vas_ida_lock);
+ rc = ida_get_new_above(ida, 0, &winid);
+ spin_unlock(&vas_ida_lock);
+
+ if (rc)
+ return rc;
+
+ if (winid > VAS_MAX_WINDOWS_PER_CHIP) {
+ pr_err("VAS: Too many (%d) open windows\n", winid);
+ vas_release_window_id(ida, winid);
+ return -EAGAIN;
+ }
+
+ return winid;
+}
+
+void vas_window_free(struct vas_window *window)
+{
+ unmap_wc_mmio_bars(window);
+ kfree(window->paste_addr_name);
+ kfree(window);
+}
+
+struct vas_window *vas_window_alloc(struct vas_instance *vinst, int id)
+{
+ struct vas_window *window;
+
+ window = kzalloc(sizeof(*window), GFP_KERNEL);
+ if (!window)
+ return NULL;
+
+ window->vinst = vinst;
+ window->winid = id;
+
+ if (map_wc_mmio_bars(window))
+ goto out_free;
+
+ return window;
+
+out_free:
+ kfree(window);
+ return NULL;
+}
+
/* stub for now */
int vas_win_close(struct vas_window *window)
{
--
2.7.4