Code used to create a ddw property that was previously scattered in
enable_ddw() is now gathered in ddw_property_create(), which deals with
allocation and filling the property, letting it ready for
of_property_add(), which now occurs in sequence.

This created an opportunity to reorganize the second part of enable_ddw():

Without this patch enable_ddw() does, in order:
kzalloc() property & members, create_ddw(), fill ddwprop inside property,
ddw_list_new_entry(), do tce_setrange_multi_pSeriesLP_walk in all memory,
of_add_property(), and list_add().

With this patch enable_ddw() does, in order:
create_ddw(), ddw_property_create(), of_add_property(),
ddw_list_new_entry(), do tce_setrange_multi_pSeriesLP_walk in all memory,
and list_add().

This change requires of_remove_property() in case anything fails after
of_add_property(), but we get to do tce_setrange_multi_pSeriesLP_walk
in all memory, which looks the most expensive operation, only if
everything else succeeds.

Signed-off-by: Leonardo Bras <leobra...@gmail.com>
---
 arch/powerpc/platforms/pseries/iommu.c | 93 ++++++++++++++++----------
 1 file changed, 57 insertions(+), 36 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/iommu.c 
b/arch/powerpc/platforms/pseries/iommu.c
index 955cf095416c..48c029386d94 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -1122,6 +1122,35 @@ static void reset_dma_window(struct pci_dev *dev, struct 
device_node *par_dn)
                         ret);
 }
 
+static struct property *ddw_property_create(const char *propname, u32 liobn, 
u64 dma_addr,
+                                           u32 page_shift, u32 window_shift)
+{
+       struct dynamic_dma_window_prop *ddwprop;
+       struct property *win64;
+
+       win64 = kzalloc(sizeof(*win64), GFP_KERNEL);
+       if (!win64)
+               return NULL;
+
+       win64->name = kstrdup(propname, GFP_KERNEL);
+       ddwprop = kzalloc(sizeof(*ddwprop), GFP_KERNEL);
+       win64->value = ddwprop;
+       win64->length = sizeof(*ddwprop);
+       if (!win64->name || !win64->value) {
+               kfree(win64);
+               kfree(win64->name);
+               kfree(win64->value);
+               return NULL;
+       }
+
+       ddwprop->liobn = cpu_to_be32(liobn);
+       ddwprop->dma_base = cpu_to_be64(dma_addr);
+       ddwprop->tce_shift = cpu_to_be32(page_shift);
+       ddwprop->window_shift = cpu_to_be32(window_shift);
+
+       return win64;
+}
+
 /* Return largest page shift based on "IO Page Sizes" output of 
ibm,query-pe-dma-window. */
 static int iommu_get_page_shift(u32 query_page_size)
 {
@@ -1167,11 +1196,11 @@ static bool enable_ddw(struct pci_dev *dev, struct 
device_node *pdn)
        struct ddw_query_response query;
        struct ddw_create_response create;
        int page_shift;
+       u64 win_addr;
        struct device_node *dn;
        u32 ddw_avail[DDW_APPLICABLE_SIZE];
        struct direct_window *window;
        struct property *win64 = NULL;
-       struct dynamic_dma_window_prop *ddwprop;
        struct failed_ddw_pdn *fpdn;
        bool default_win_removed = false;
        bool pmem_present;
@@ -1286,65 +1315,54 @@ static bool enable_ddw(struct pci_dev *dev, struct 
device_node *pdn)
                        1ULL << page_shift);
                goto out_failed;
        }
-       win64 = kzalloc(sizeof(struct property), GFP_KERNEL);
-       if (!win64) {
-               dev_info(&dev->dev,
-                       "couldn't allocate property for 64bit dma window\n");
-               goto out_failed;
-       }
-       win64->name = kstrdup(DIRECT64_PROPNAME, GFP_KERNEL);
-       win64->value = ddwprop = kmalloc(sizeof(*ddwprop), GFP_KERNEL);
-       win64->length = sizeof(*ddwprop);
-       if (!win64->name || !win64->value) {
-               dev_info(&dev->dev,
-                       "couldn't allocate property name and value\n");
-               goto out_free_prop;
-       }
 
        ret = create_ddw(dev, ddw_avail, &create, page_shift, len);
        if (ret != 0)
-               goto out_free_prop;
-
-       ddwprop->liobn = cpu_to_be32(create.liobn);
-       ddwprop->dma_base = cpu_to_be64(((u64)create.addr_hi << 32) |
-                       create.addr_lo);
-       ddwprop->tce_shift = cpu_to_be32(page_shift);
-       ddwprop->window_shift = cpu_to_be32(len);
+               goto out_failed;
 
        dev_dbg(&dev->dev, "created tce table LIOBN 0x%x for %pOF\n",
                  create.liobn, dn);
 
-       window = ddw_list_new_entry(pdn, ddwprop);
+       win_addr = ((u64)create.addr_hi << 32) | create.addr_lo;
+       win64 = ddw_property_create(DIRECT64_PROPNAME, create.liobn, win_addr,
+                                   page_shift, len);
+       if (!win64) {
+               dev_info(&dev->dev,
+                        "couldn't allocate property, property name, or 
value\n");
+               goto out_del_win;
+       }
+
+       ret = of_add_property(pdn, win64);
+       if (ret) {
+               dev_err(&dev->dev, "unable to add dma window property for %pOF: 
%d",
+                       pdn, ret);
+               goto out_free_prop;
+       }
+
+       window = ddw_list_new_entry(pdn, win64->value);
        if (!window)
-               goto out_clear_window;
+               goto out_del_prop;
 
        ret = walk_system_ram_range(0, memblock_end_of_DRAM() >> PAGE_SHIFT,
                        win64->value, tce_setrange_multi_pSeriesLP_walk);
        if (ret) {
                dev_info(&dev->dev, "failed to map direct window for %pOF: 
%d\n",
                         dn, ret);
-               goto out_free_window;
-       }
-
-       ret = of_add_property(pdn, win64);
-       if (ret) {
-               dev_err(&dev->dev, "unable to add dma window property for %pOF: 
%d",
-                        pdn, ret);
-               goto out_free_window;
+               goto out_del_list;
        }
 
        spin_lock(&direct_window_list_lock);
        list_add(&window->list, &direct_window_list);
        spin_unlock(&direct_window_list_lock);
 
-       dev->dev.archdata.dma_offset = be64_to_cpu(ddwprop->dma_base);
+       dev->dev.archdata.dma_offset = win_addr;
        goto out_unlock;
 
-out_free_window:
+out_del_list:
        kfree(window);
 
-out_clear_window:
-       remove_ddw(pdn, true);
+out_del_prop:
+       of_remove_property(pdn, win64);
 
 out_free_prop:
        kfree(win64->name);
@@ -1352,6 +1370,9 @@ static bool enable_ddw(struct pci_dev *dev, struct 
device_node *pdn)
        kfree(win64);
        win64 = NULL;
 
+out_del_win:
+       remove_ddw(pdn, true);
+
 out_failed:
        if (default_win_removed)
                reset_dma_window(dev, pdn);
-- 
2.30.2

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