dmaengine: ti: k3-udma: Fix smatch warnings

Smatch reports below warnings [1] wrt dereferencing rm_res when it can
potentially be ERR_PTR(). This is possible when entire range is
allocated to Linux
Fix this case by making sure, there is no deference of rm_res when its
ERR_PTR().

[1]:
 drivers/dma/ti/k3-udma.c:4524 udma_setup_resources() error: 'rm_res' dereferencing possible ERR_PTR()
 drivers/dma/ti/k3-udma.c:4537 udma_setup_resources() error: 'rm_res' dereferencing possible ERR_PTR()
 drivers/dma/ti/k3-udma.c:4681 bcdma_setup_resources() error: 'rm_res' dereferencing possible ERR_PTR()
 drivers/dma/ti/k3-udma.c:4696 bcdma_setup_resources() error: 'rm_res' dereferencing possible ERR_PTR()
 drivers/dma/ti/k3-udma.c:4711 bcdma_setup_resources() error: 'rm_res' dereferencing possible ERR_PTR()
 drivers/dma/ti/k3-udma.c:4848 pktdma_setup_resources() error: 'rm_res' dereferencing possible ERR_PTR()
 drivers/dma/ti/k3-udma.c:4861 pktdma_setup_resources() error: 'rm_res' dereferencing possible ERR_PTR()

Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20211209180957.29036-1-vigneshr@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index 041d8e32d6300551210769a339d1acafd4ad5a8d..6e56d1cef5eeec0343a65dc9688935cb691647d5 100644 (file)
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -4534,45 +4534,60 @@ static int udma_setup_resources(struct udma_dev *ud)
        rm_res = tisci_rm->rm_ranges[RM_RANGE_TCHAN];
        if (IS_ERR(rm_res)) {
                bitmap_zero(ud->tchan_map, ud->tchan_cnt);
+               irq_res.sets = 1;
        } else {
                bitmap_fill(ud->tchan_map, ud->tchan_cnt);
                for (i = 0; i < rm_res->sets; i++)
                        udma_mark_resource_ranges(ud, ud->tchan_map,
                                                  &rm_res->desc[i], "tchan");
+               irq_res.sets = rm_res->sets;
        }
-       irq_res.sets = rm_res->sets;
 
        /* rchan and matching default flow ranges */
        rm_res = tisci_rm->rm_ranges[RM_RANGE_RCHAN];
        if (IS_ERR(rm_res)) {
                bitmap_zero(ud->rchan_map, ud->rchan_cnt);
+               irq_res.sets++;
        } else {
                bitmap_fill(ud->rchan_map, ud->rchan_cnt);
                for (i = 0; i < rm_res->sets; i++)
                        udma_mark_resource_ranges(ud, ud->rchan_map,
                                                  &rm_res->desc[i], "rchan");
+               irq_res.sets += rm_res->sets;
        }
 
-       irq_res.sets += rm_res->sets;
        irq_res.desc = kcalloc(irq_res.sets, sizeof(*irq_res.desc), GFP_KERNEL);
+       if (!irq_res.desc)
+               return -ENOMEM;
        rm_res = tisci_rm->rm_ranges[RM_RANGE_TCHAN];
-       for (i = 0; i < rm_res->sets; i++) {
-               irq_res.desc[i].start = rm_res->desc[i].start;
-               irq_res.desc[i].num = rm_res->desc[i].num;
-               irq_res.desc[i].start_sec = rm_res->desc[i].start_sec;
-               irq_res.desc[i].num_sec = rm_res->desc[i].num_sec;
+       if (IS_ERR(rm_res)) {
+               irq_res.desc[0].start = 0;
+               irq_res.desc[0].num = ud->tchan_cnt;
+               i = 1;
+       } else {
+               for (i = 0; i < rm_res->sets; i++) {
+                       irq_res.desc[i].start = rm_res->desc[i].start;
+                       irq_res.desc[i].num = rm_res->desc[i].num;
+                       irq_res.desc[i].start_sec = rm_res->desc[i].start_sec;
+                       irq_res.desc[i].num_sec = rm_res->desc[i].num_sec;
+               }
        }
        rm_res = tisci_rm->rm_ranges[RM_RANGE_RCHAN];
-       for (j = 0; j < rm_res->sets; j++, i++) {
-               if (rm_res->desc[j].num) {
-                       irq_res.desc[i].start = rm_res->desc[j].start +
-                                       ud->soc_data->oes.udma_rchan;
-                       irq_res.desc[i].num = rm_res->desc[j].num;
-               }
-               if (rm_res->desc[j].num_sec) {
-                       irq_res.desc[i].start_sec = rm_res->desc[j].start_sec +
-                                       ud->soc_data->oes.udma_rchan;
-                       irq_res.desc[i].num_sec = rm_res->desc[j].num_sec;
+       if (IS_ERR(rm_res)) {
+               irq_res.desc[i].start = 0;
+               irq_res.desc[i].num = ud->rchan_cnt;
+       } else {
+               for (j = 0; j < rm_res->sets; j++, i++) {
+                       if (rm_res->desc[j].num) {
+                               irq_res.desc[i].start = rm_res->desc[j].start +
+                                               ud->soc_data->oes.udma_rchan;
+                               irq_res.desc[i].num = rm_res->desc[j].num;
+                       }
+                       if (rm_res->desc[j].num_sec) {
+                               irq_res.desc[i].start_sec = rm_res->desc[j].start_sec +
+                                               ud->soc_data->oes.udma_rchan;
+                               irq_res.desc[i].num_sec = rm_res->desc[j].num_sec;
+                       }
                }
        }
        ret = ti_sci_inta_msi_domain_alloc_irqs(ud->dev, &irq_res);
@@ -4690,14 +4705,15 @@ static int bcdma_setup_resources(struct udma_dev *ud)
                rm_res = tisci_rm->rm_ranges[RM_RANGE_BCHAN];
                if (IS_ERR(rm_res)) {
                        bitmap_zero(ud->bchan_map, ud->bchan_cnt);
+                       irq_res.sets++;
                } else {
                        bitmap_fill(ud->bchan_map, ud->bchan_cnt);
                        for (i = 0; i < rm_res->sets; i++)
                                udma_mark_resource_ranges(ud, ud->bchan_map,
                                                          &rm_res->desc[i],
                                                          "bchan");
+                       irq_res.sets += rm_res->sets;
                }
-               irq_res.sets += rm_res->sets;
        }
 
        /* tchan ranges */
@@ -4705,14 +4721,15 @@ static int bcdma_setup_resources(struct udma_dev *ud)
                rm_res = tisci_rm->rm_ranges[RM_RANGE_TCHAN];
                if (IS_ERR(rm_res)) {
                        bitmap_zero(ud->tchan_map, ud->tchan_cnt);
+                       irq_res.sets += 2;
                } else {
                        bitmap_fill(ud->tchan_map, ud->tchan_cnt);
                        for (i = 0; i < rm_res->sets; i++)
                                udma_mark_resource_ranges(ud, ud->tchan_map,
                                                          &rm_res->desc[i],
                                                          "tchan");
+                       irq_res.sets += rm_res->sets * 2;
                }
-               irq_res.sets += rm_res->sets * 2;
        }
 
        /* rchan ranges */
@@ -4720,47 +4737,72 @@ static int bcdma_setup_resources(struct udma_dev *ud)
                rm_res = tisci_rm->rm_ranges[RM_RANGE_RCHAN];
                if (IS_ERR(rm_res)) {
                        bitmap_zero(ud->rchan_map, ud->rchan_cnt);
+                       irq_res.sets += 2;
                } else {
                        bitmap_fill(ud->rchan_map, ud->rchan_cnt);
                        for (i = 0; i < rm_res->sets; i++)
                                udma_mark_resource_ranges(ud, ud->rchan_map,
                                                          &rm_res->desc[i],
                                                          "rchan");
+                       irq_res.sets += rm_res->sets * 2;
                }
-               irq_res.sets += rm_res->sets * 2;
        }
 
        irq_res.desc = kcalloc(irq_res.sets, sizeof(*irq_res.desc), GFP_KERNEL);
+       if (!irq_res.desc)
+               return -ENOMEM;
        if (ud->bchan_cnt) {
                rm_res = tisci_rm->rm_ranges[RM_RANGE_BCHAN];
-               for (i = 0; i < rm_res->sets; i++) {
-                       irq_res.desc[i].start = rm_res->desc[i].start +
-                                               oes->bcdma_bchan_ring;
-                       irq_res.desc[i].num = rm_res->desc[i].num;
+               if (IS_ERR(rm_res)) {
+                       irq_res.desc[0].start = oes->bcdma_bchan_ring;
+                       irq_res.desc[0].num = ud->bchan_cnt;
+                       i = 1;
+               } else {
+                       for (i = 0; i < rm_res->sets; i++) {
+                               irq_res.desc[i].start = rm_res->desc[i].start +
+                                                       oes->bcdma_bchan_ring;
+                               irq_res.desc[i].num = rm_res->desc[i].num;
+                       }
                }
        }
        if (ud->tchan_cnt) {
                rm_res = tisci_rm->rm_ranges[RM_RANGE_TCHAN];
-               for (j = 0; j < rm_res->sets; j++, i += 2) {
-                       irq_res.desc[i].start = rm_res->desc[j].start +
-                                               oes->bcdma_tchan_data;
-                       irq_res.desc[i].num = rm_res->desc[j].num;
-
-                       irq_res.desc[i + 1].start = rm_res->desc[j].start +
-                                               oes->bcdma_tchan_ring;
-                       irq_res.desc[i + 1].num = rm_res->desc[j].num;
+               if (IS_ERR(rm_res)) {
+                       irq_res.desc[i].start = oes->bcdma_tchan_data;
+                       irq_res.desc[i].num = ud->tchan_cnt;
+                       irq_res.desc[i + 1].start = oes->bcdma_tchan_ring;
+                       irq_res.desc[i + 1].num = ud->tchan_cnt;
+                       i += 2;
+               } else {
+                       for (j = 0; j < rm_res->sets; j++, i += 2) {
+                               irq_res.desc[i].start = rm_res->desc[j].start +
+                                                       oes->bcdma_tchan_data;
+                               irq_res.desc[i].num = rm_res->desc[j].num;
+
+                               irq_res.desc[i + 1].start = rm_res->desc[j].start +
+                                                       oes->bcdma_tchan_ring;
+                               irq_res.desc[i + 1].num = rm_res->desc[j].num;
+                       }
                }
        }
        if (ud->rchan_cnt) {
                rm_res = tisci_rm->rm_ranges[RM_RANGE_RCHAN];
-               for (j = 0; j < rm_res->sets; j++, i += 2) {
-                       irq_res.desc[i].start = rm_res->desc[j].start +
-                                               oes->bcdma_rchan_data;
-                       irq_res.desc[i].num = rm_res->desc[j].num;
-
-                       irq_res.desc[i + 1].start = rm_res->desc[j].start +
-                                               oes->bcdma_rchan_ring;
-                       irq_res.desc[i + 1].num = rm_res->desc[j].num;
+               if (IS_ERR(rm_res)) {
+                       irq_res.desc[i].start = oes->bcdma_rchan_data;
+                       irq_res.desc[i].num = ud->rchan_cnt;
+                       irq_res.desc[i + 1].start = oes->bcdma_rchan_ring;
+                       irq_res.desc[i + 1].num = ud->rchan_cnt;
+                       i += 2;
+               } else {
+                       for (j = 0; j < rm_res->sets; j++, i += 2) {
+                               irq_res.desc[i].start = rm_res->desc[j].start +
+                                                       oes->bcdma_rchan_data;
+                               irq_res.desc[i].num = rm_res->desc[j].num;
+
+                               irq_res.desc[i + 1].start = rm_res->desc[j].start +
+                                                       oes->bcdma_rchan_ring;
+                               irq_res.desc[i + 1].num = rm_res->desc[j].num;
+                       }
                }
        }
 
@@ -4858,39 +4900,54 @@ static int pktdma_setup_resources(struct udma_dev *ud)
        if (IS_ERR(rm_res)) {
                /* all rflows are assigned exclusively to Linux */
                bitmap_zero(ud->rflow_in_use, ud->rflow_cnt);
+               irq_res.sets = 1;
        } else {
                bitmap_fill(ud->rflow_in_use, ud->rflow_cnt);
                for (i = 0; i < rm_res->sets; i++)
                        udma_mark_resource_ranges(ud, ud->rflow_in_use,
                                                  &rm_res->desc[i], "rflow");
+               irq_res.sets = rm_res->sets;
        }
-       irq_res.sets = rm_res->sets;
 
        /* tflow ranges */
        rm_res = tisci_rm->rm_ranges[RM_RANGE_TFLOW];
        if (IS_ERR(rm_res)) {
                /* all tflows are assigned exclusively to Linux */
                bitmap_zero(ud->tflow_map, ud->tflow_cnt);
+               irq_res.sets++;
        } else {
                bitmap_fill(ud->tflow_map, ud->tflow_cnt);
                for (i = 0; i < rm_res->sets; i++)
                        udma_mark_resource_ranges(ud, ud->tflow_map,
                                                  &rm_res->desc[i], "tflow");
+               irq_res.sets += rm_res->sets;
        }
-       irq_res.sets += rm_res->sets;
 
        irq_res.desc = kcalloc(irq_res.sets, sizeof(*irq_res.desc), GFP_KERNEL);
+       if (!irq_res.desc)
+               return -ENOMEM;
        rm_res = tisci_rm->rm_ranges[RM_RANGE_TFLOW];
-       for (i = 0; i < rm_res->sets; i++) {
-               irq_res.desc[i].start = rm_res->desc[i].start +
-                                       oes->pktdma_tchan_flow;
-               irq_res.desc[i].num = rm_res->desc[i].num;
+       if (IS_ERR(rm_res)) {
+               irq_res.desc[0].start = oes->pktdma_tchan_flow;
+               irq_res.desc[0].num = ud->tflow_cnt;
+               i = 1;
+       } else {
+               for (i = 0; i < rm_res->sets; i++) {
+                       irq_res.desc[i].start = rm_res->desc[i].start +
+                                               oes->pktdma_tchan_flow;
+                       irq_res.desc[i].num = rm_res->desc[i].num;
+               }
        }
        rm_res = tisci_rm->rm_ranges[RM_RANGE_RFLOW];
-       for (j = 0; j < rm_res->sets; j++, i++) {
-               irq_res.desc[i].start = rm_res->desc[j].start +
-                                       oes->pktdma_rchan_flow;
-               irq_res.desc[i].num = rm_res->desc[j].num;
+       if (IS_ERR(rm_res)) {
+               irq_res.desc[i].start = oes->pktdma_rchan_flow;
+               irq_res.desc[i].num = ud->rflow_cnt;
+       } else {
+               for (j = 0; j < rm_res->sets; j++, i++) {
+                       irq_res.desc[i].start = rm_res->desc[j].start +
+                                               oes->pktdma_rchan_flow;
+                       irq_res.desc[i].num = rm_res->desc[j].num;
+               }
        }
        ret = ti_sci_inta_msi_domain_alloc_irqs(ud->dev, &irq_res);
        kfree(irq_res.desc);