cxl/pci: Simplify register setup

It is desirable to retain the mappings from the calling function. By
simplifying this code, it will be much more straightforward to do that.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210716231548.174778-3-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index b6bda39..53927f9 100644 (file)
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -140,7 +140,6 @@ struct cxl_device_reg_map {
 };
 
 struct cxl_register_map {
-       struct list_head list;
        u64 block_offset;
        u8 reg_type;
        u8 barno;

diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index 90a1c89..47315bb 100644 (file)
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -1091,9 +1091,8 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
        struct device *dev = &pdev->dev;
        u32 regloc_size, regblocks;
        void __iomem *base;
-       int regloc, i;
-       struct cxl_register_map *map, *n;
-       LIST_HEAD(register_maps);
+       int regloc, i, n_maps;
+       struct cxl_register_map *map, maps[CXL_REGLOC_RBI_TYPES];
        int ret = 0;
 
        regloc = cxl_mem_dvsec(pdev, PCI_DVSEC_ID_CXL_REGLOC_DVSEC_ID);
@@ -1112,7 +1111,7 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
        regloc += PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET;
        regblocks = (regloc_size - PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET) / 8;
 
-       for (i = 0; i < regblocks; i++, regloc += 8) {
+       for (i = 0, n_maps = 0; i < regblocks; i++, regloc += 8) {
                u32 reg_lo, reg_hi;
                u8 reg_type;
                u64 offset;
@@ -1131,20 +1130,11 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
                if (reg_type > CXL_REGLOC_RBI_MEMDEV)
                        continue;
 
-               map = kzalloc(sizeof(*map), GFP_KERNEL);
-               if (!map) {
-                       ret = -ENOMEM;
-                       goto free_maps;
-               }
-
-               list_add(&map->list, &register_maps);
-
                base = cxl_mem_map_regblock(cxlm, bar, offset);
-               if (!base) {
-                       ret = -ENOMEM;
-                       goto free_maps;
-               }
+               if (!base)
+                       return -ENOMEM;
 
+               map = &maps[n_maps];
                map->barno = bar;
                map->block_offset = offset;
                map->reg_type = reg_type;
@@ -1155,21 +1145,17 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
                cxl_mem_unmap_regblock(cxlm, base);
 
                if (ret)
-                       goto free_maps;
+                       return ret;
+
+               n_maps++;
        }
 
        pci_release_mem_regions(pdev);
 
-       list_for_each_entry(map, &register_maps, list) {
-               ret = cxl_map_regs(cxlm, map);
+       for (i = 0; i < n_maps; i++) {
+               ret = cxl_map_regs(cxlm, &maps[i]);
                if (ret)
-                       goto free_maps;
-       }
-
-free_maps:
-       list_for_each_entry_safe(map, n, &register_maps, list) {
-               list_del(&map->list);
-               kfree(map);
+                       break;
        }
 
        return ret;

diff --git a/drivers/cxl/pci.h b/drivers/cxl/pci.h
index dad7a83..8c1a588 100644 (file)
--- a/drivers/cxl/pci.h
+++ b/drivers/cxl/pci.h
@@ -25,6 +25,7 @@
 #define CXL_REGLOC_RBI_COMPONENT 1
 #define CXL_REGLOC_RBI_VIRT 2
 #define CXL_REGLOC_RBI_MEMDEV 3
+#define CXL_REGLOC_RBI_TYPES CXL_REGLOC_RBI_MEMDEV + 1
 
 #define CXL_REGLOC_ADDR_MASK GENMASK(31, 16)