staging: vc04_services: Move global variables tracking allocated pages

The variables tracking allocated pages fragments in vchiq_arm.c
can be easily moved to struct vchiq_drv_mgmt instead of being global.
This helps us to drop the non-essential global variables in the vchiq
interface.

No functional changes intended in this patch.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Stefan Wahren <wahrenst@gmx.net>
Link: https://lore.kernel.org/r/20240412075743.60712-7-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
index 396c686b1978ceb1a759f87db6ff009572f9e8f2..29f9affe53040ab33775d275211e177fc8a2d8b3 100644 (file)
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
@@ -130,12 +130,6 @@ struct vchiq_pagelist_info {
 };
 
 static void __iomem *g_regs;
-static unsigned int g_fragments_size;
-static char *g_fragments_base;
-static char *g_free_fragments;
-static struct semaphore g_free_fragments_sema;
-
-static DEFINE_SEMAPHORE(g_free_fragments_mutex, 1);
 
 static int
 vchiq_blocking_bulk_transfer(struct vchiq_instance *instance, unsigned int handle, void *data,
@@ -414,20 +408,20 @@ create_pagelist(struct vchiq_instance *instance, char *buf, char __user *ubuf,
            (drv_mgmt->info->cache_line_size - 1)))) {
                char *fragments;
 
-               if (down_interruptible(&g_free_fragments_sema)) {
+               if (down_interruptible(&drv_mgmt->free_fragments_sema)) {
                        cleanup_pagelistinfo(instance, pagelistinfo);
                        return NULL;
                }
 
-               WARN_ON(!g_free_fragments);
+               WARN_ON(!drv_mgmt->free_fragments);
 
-               down(&g_free_fragments_mutex);
-               fragments = g_free_fragments;
+               down(&drv_mgmt->free_fragments_mutex);
+               fragments = drv_mgmt->free_fragments;
                WARN_ON(!fragments);
-               g_free_fragments = *(char **)g_free_fragments;
-               up(&g_free_fragments_mutex);
+               drv_mgmt->free_fragments = *(char **)drv_mgmt->free_fragments;
+               up(&drv_mgmt->free_fragments_mutex);
                pagelist->type = PAGELIST_READ_WITH_FRAGMENTS +
-                       (fragments - g_fragments_base) / g_fragments_size;
+                       (fragments - drv_mgmt->fragments_base) / drv_mgmt->fragments_size;
        }
 
        return pagelistinfo;
@@ -455,10 +449,10 @@ free_pagelist(struct vchiq_instance *instance, struct vchiq_pagelist_info *pagel
        pagelistinfo->scatterlist_mapped = 0;
 
        /* Deal with any partial cache lines (fragments) */
-       if (pagelist->type >= PAGELIST_READ_WITH_FRAGMENTS && g_fragments_base) {
-               char *fragments = g_fragments_base +
+       if (pagelist->type >= PAGELIST_READ_WITH_FRAGMENTS && drv_mgmt->fragments_base) {
+               char *fragments = drv_mgmt->fragments_base +
                        (pagelist->type - PAGELIST_READ_WITH_FRAGMENTS) *
-                       g_fragments_size;
+                       drv_mgmt->fragments_size;
                int head_bytes, tail_bytes;
 
                head_bytes = (drv_mgmt->info->cache_line_size - pagelist->offset) &
@@ -483,11 +477,11 @@ free_pagelist(struct vchiq_instance *instance, struct vchiq_pagelist_info *pagel
                                fragments + drv_mgmt->info->cache_line_size,
                                tail_bytes);
 
-               down(&g_free_fragments_mutex);
-               *(char **)fragments = g_free_fragments;
-               g_free_fragments = fragments;
-               up(&g_free_fragments_mutex);
-               up(&g_free_fragments_sema);
+               down(&drv_mgmt->free_fragments_mutex);
+               *(char **)fragments = drv_mgmt->free_fragments;
+               drv_mgmt->free_fragments = fragments;
+               up(&drv_mgmt->free_fragments_mutex);
+               up(&drv_mgmt->free_fragments_sema);
        }
 
        /* Need to mark all the pages dirty. */
@@ -523,11 +517,11 @@ static int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state
        if (err < 0)
                return err;
 
-       g_fragments_size = 2 * drv_mgmt->info->cache_line_size;
+       drv_mgmt->fragments_size = 2 * drv_mgmt->info->cache_line_size;
 
        /* Allocate space for the channels in coherent memory */
        slot_mem_size = PAGE_ALIGN(TOTAL_SLOTS * VCHIQ_SLOT_SIZE);
-       frag_mem_size = PAGE_ALIGN(g_fragments_size * MAX_FRAGMENTS);
+       frag_mem_size = PAGE_ALIGN(drv_mgmt->fragments_size * MAX_FRAGMENTS);
 
        slot_mem = dmam_alloc_coherent(dev, slot_mem_size + frag_mem_size,
                                       &slot_phys, GFP_KERNEL);
@@ -547,15 +541,16 @@ static int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state
        vchiq_slot_zero->platform_data[VCHIQ_PLATFORM_FRAGMENTS_COUNT_IDX] =
                MAX_FRAGMENTS;
 
-       g_fragments_base = (char *)slot_mem + slot_mem_size;
+       drv_mgmt->fragments_base = (char *)slot_mem + slot_mem_size;
 
-       g_free_fragments = g_fragments_base;
+       drv_mgmt->free_fragments = drv_mgmt->fragments_base;
        for (i = 0; i < (MAX_FRAGMENTS - 1); i++) {
-               *(char **)&g_fragments_base[i * g_fragments_size] =
-                       &g_fragments_base[(i + 1) * g_fragments_size];
+               *(char **)&drv_mgmt->fragments_base[i * drv_mgmt->fragments_size] =
+                       &drv_mgmt->fragments_base[(i + 1) * drv_mgmt->fragments_size];
        }
-       *(char **)&g_fragments_base[i * g_fragments_size] = NULL;
-       sema_init(&g_free_fragments_sema, MAX_FRAGMENTS);
+       *(char **)&drv_mgmt->fragments_base[i * drv_mgmt->fragments_size] = NULL;
+       sema_init(&drv_mgmt->free_fragments_sema, MAX_FRAGMENTS);
+       sema_init(&drv_mgmt->free_fragments_mutex, 1);
 
        err = vchiq_init_state(state, vchiq_slot_zero, dev);
        if (err)

diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
index 48f6abee591ff7a03ad6105a071ec8789162d5a1..52013bbc517170a4ec622ae89d5456bb8dcdf3db 100644 (file)
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
@@ -44,6 +44,12 @@ struct vchiq_drv_mgmt {
        struct mutex connected_mutex;
 
        void (*deferred_callback[VCHIQ_DRV_MAX_CALLBACKS])(void);
+
+       struct semaphore free_fragments_sema;
+       struct semaphore free_fragments_mutex;
+       char *fragments_base;
+       char *free_fragments;
+       unsigned int fragments_size;
 };
 
 struct user_service {