From: Bjorn Helgaas <bhelgaas@google.com>
Date: Mon, 23 Mar 2020 17:26:01 -0700
Subject: PCI/DPC: Move DPC data into struct pci_dev
Git-commit: be06c1b42eea749547d2f0248dc0a7c1153f67b9
Patch-mainline: v5.7-rc1
References: bsc#1169263, jsc#SLE-10700, jsc#SLE-9457, jsc#SLE-12300

We only need 25 bits of data for DPC, so I don't think it's worth the
complexity of allocating and keeping track of the struct dpc_dev separately
from the pci_dev.  Move that data into the struct pci_dev.

Link: https://lore.kernel.org/r/98323eaa18080adbe5bb30846862f09f8722d4b3.1585000084.git.sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/pci/pcie/dpc.c | 103 +++++++++++++++----------------------------------
 include/linux/pci.h    |   5 +++
 2 files changed, 36 insertions(+), 72 deletions(-)

--- a/drivers/pci/pcie/dpc.c
+++ b/drivers/pci/pcie/dpc.c
@@ -17,13 +17,6 @@
 #include "portdrv.h"
 #include "../pci.h"
 
-struct dpc_dev {
-	struct pcie_device	*dev;
-	u16			cap_pos;
-	bool			rp_extensions;
-	u8			rp_log_size;
-};
-
 static const char * const rp_pio_error_string[] = {
 	"Configuration Request received UR Completion",	 /* Bit Position 0  */
 	"Configuration Request received CA Completion",	 /* Bit Position 1  */
@@ -46,63 +39,42 @@ static const char * const rp_pio_error_s
 	"Memory Request Completion Timeout",		 /* Bit Position 18 */
 };
 
-static struct dpc_dev *to_dpc_dev(struct pci_dev *dev)
-{
-	struct device *device;
-
-	device = pcie_port_find_device(dev, PCIE_PORT_SERVICE_DPC);
-	if (!device)
-		return NULL;
-	return get_service_data(to_pcie_device(device));
-}
-
 void pci_save_dpc_state(struct pci_dev *dev)
 {
-	struct dpc_dev *dpc;
 	struct pci_cap_saved_state *save_state;
 	u16 *cap;
 
 	if (!pci_is_pcie(dev))
 		return;
 
-	dpc = to_dpc_dev(dev);
-	if (!dpc)
-		return;
-
 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_DPC);
 	if (!save_state)
 		return;
 
 	cap = (u16 *)&save_state->cap.data[0];
-	pci_read_config_word(dev, dpc->cap_pos + PCI_EXP_DPC_CTL, cap);
+	pci_read_config_word(dev, dev->dpc_cap + PCI_EXP_DPC_CTL, cap);
 }
 
 void pci_restore_dpc_state(struct pci_dev *dev)
 {
-	struct dpc_dev *dpc;
 	struct pci_cap_saved_state *save_state;
 	u16 *cap;
 
 	if (!pci_is_pcie(dev))
 		return;
 
-	dpc = to_dpc_dev(dev);
-	if (!dpc)
-		return;
-
 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_DPC);
 	if (!save_state)
 		return;
 
 	cap = (u16 *)&save_state->cap.data[0];
-	pci_write_config_word(dev, dpc->cap_pos + PCI_EXP_DPC_CTL, *cap);
+	pci_write_config_word(dev, dev->dpc_cap + PCI_EXP_DPC_CTL, *cap);
 }
 
-static int dpc_wait_rp_inactive(struct dpc_dev *dpc)
+static int dpc_wait_rp_inactive(struct pci_dev *pdev)
 {
 	unsigned long timeout = jiffies + HZ;
-	struct pci_dev *pdev = dpc->dev->port;
-	u16 cap = dpc->cap_pos, status;
+	u16 cap = pdev->dpc_cap, status;
 
 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 	while (status & PCI_EXP_DPC_RP_BUSY &&
@@ -119,15 +91,13 @@ static int dpc_wait_rp_inactive(struct d
 
 static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev)
 {
-	struct dpc_dev *dpc;
 	u16 cap;
 
 	/*
 	 * DPC disables the Link automatically in hardware, so it has
 	 * already been reset by the time we get here.
 	 */
-	dpc = to_dpc_dev(pdev);
-	cap = dpc->cap_pos;
+	cap = pdev->dpc_cap;
 
 	/*
 	 * Wait until the Link is inactive, then clear DPC Trigger Status
@@ -135,7 +105,7 @@ static pci_ers_result_t dpc_reset_link(s
 	 */
 	pcie_wait_for_link(pdev, false);
 
-	if (dpc->rp_extensions && dpc_wait_rp_inactive(dpc))
+	if (pdev->dpc_rp_extensions && dpc_wait_rp_inactive(pdev))
 		return PCI_ERS_RESULT_DISCONNECT;
 
 	pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS,
@@ -147,10 +117,9 @@ static pci_ers_result_t dpc_reset_link(s
 	return PCI_ERS_RESULT_RECOVERED;
 }
 
-static void dpc_process_rp_pio_error(struct dpc_dev *dpc)
+static void dpc_process_rp_pio_error(struct pci_dev *pdev)
 {
-	struct pci_dev *pdev = dpc->dev->port;
-	u16 cap = dpc->cap_pos, dpc_status, first_error;
+	u16 cap = pdev->dpc_cap, dpc_status, first_error;
 	u32 status, mask, sev, syserr, exc, dw0, dw1, dw2, dw3, log, prefix;
 	int i;
 
@@ -175,7 +144,7 @@ static void dpc_process_rp_pio_error(str
 				first_error == i ? " (First)" : "");
 	}
 
-	if (dpc->rp_log_size < 4)
+	if (pdev->dpc_rp_log_size < 4)
 		goto clear_status;
 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG,
 			      &dw0);
@@ -188,12 +157,12 @@ static void dpc_process_rp_pio_error(str
 	pci_err(pdev, "TLP Header: %#010x %#010x %#010x %#010x\n",
 		dw0, dw1, dw2, dw3);
 
-	if (dpc->rp_log_size < 5)
+	if (pdev->dpc_rp_log_size < 5)
 		goto clear_status;
 	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_IMPSPEC_LOG, &log);
 	pci_err(pdev, "RP PIO ImpSpec Log %#010x\n", log);
 
-	for (i = 0; i < dpc->rp_log_size - 5; i++) {
+	for (i = 0; i < pdev->dpc_rp_log_size - 5; i++) {
 		pci_read_config_dword(pdev,
 			cap + PCI_EXP_DPC_RP_PIO_TLPPREFIX_LOG, &prefix);
 		pci_err(pdev, "TLP Prefix Header: dw%d, %#010x\n", i, prefix);
@@ -226,10 +195,9 @@ static int dpc_get_aer_uncorrect_severit
 
 static irqreturn_t dpc_handler(int irq, void *context)
 {
+	struct pci_dev *pdev = context;
+	u16 cap = pdev->dpc_cap, status, source, reason, ext_reason;
 	struct aer_err_info info;
-	struct dpc_dev *dpc = context;
-	struct pci_dev *pdev = dpc->dev->port;
-	u16 cap = dpc->cap_pos, status, source, reason, ext_reason;
 
 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_SOURCE_ID, &source);
@@ -248,8 +216,8 @@ static irqreturn_t dpc_handler(int irq,
 				     "reserved error");
 
 	/* show RP PIO error detail information */
-	if (dpc->rp_extensions && reason == 3 && ext_reason == 0)
-		dpc_process_rp_pio_error(dpc);
+	if (pdev->dpc_rp_extensions && reason == 3 && ext_reason == 0)
+		dpc_process_rp_pio_error(pdev);
 	else if (reason == 0 &&
 		 dpc_get_aer_uncorrect_severity(pdev, &info) &&
 		 aer_get_device_error_info(pdev, &info)) {
@@ -266,9 +234,8 @@ static irqreturn_t dpc_handler(int irq,
 
 static irqreturn_t dpc_irq(int irq, void *context)
 {
-	struct dpc_dev *dpc = (struct dpc_dev *)context;
-	struct pci_dev *pdev = dpc->dev->port;
-	u16 cap = dpc->cap_pos, status;
+	struct pci_dev *pdev = context;
+	u16 cap = pdev->dpc_cap, status;
 
 	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 
@@ -285,7 +252,6 @@ static irqreturn_t dpc_irq(int irq, void
 #define FLAG(x, y) (((x) & (y)) ? '+' : '-')
 static int dpc_probe(struct pcie_device *dev)
 {
-	struct dpc_dev *dpc;
 	struct pci_dev *pdev = dev->port;
 	struct device *device = &dev->device;
 	int status;
@@ -294,43 +260,37 @@ static int dpc_probe(struct pcie_device
 	if (pcie_aer_get_firmware_first(pdev))
 		return -ENOTSUPP;
 
-	dpc = devm_kzalloc(device, sizeof(*dpc), GFP_KERNEL);
-	if (!dpc)
-		return -ENOMEM;
-
-	dpc->cap_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DPC);
-	dpc->dev = dev;
-	set_service_data(dev, dpc);
+	pdev->dpc_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DPC);
 
 	status = devm_request_threaded_irq(device, dev->irq, dpc_irq,
 					   dpc_handler, IRQF_SHARED,
-					   "pcie-dpc", dpc);
+					   "pcie-dpc", pdev);
 	if (status) {
 		pci_warn(pdev, "request IRQ%d failed: %d\n", dev->irq,
 			 status);
 		return status;
 	}
 
-	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CAP, &cap);
-	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl);
+	pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CAP, &cap);
+	pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl);
 
-	dpc->rp_extensions = (cap & PCI_EXP_DPC_CAP_RP_EXT);
-	if (dpc->rp_extensions) {
-		dpc->rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8;
-		if (dpc->rp_log_size < 4 || dpc->rp_log_size > 9) {
+	pdev->dpc_rp_extensions = (cap & PCI_EXP_DPC_CAP_RP_EXT) ? 1 : 0;
+	if (pdev->dpc_rp_extensions) {
+		pdev->dpc_rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8;
+		if (pdev->dpc_rp_log_size < 4 || pdev->dpc_rp_log_size > 9) {
 			pci_err(pdev, "RP PIO log size %u is invalid\n",
-				dpc->rp_log_size);
-			dpc->rp_log_size = 0;
+				pdev->dpc_rp_log_size);
+			pdev->dpc_rp_log_size = 0;
 		}
 	}
 
 	ctl = (ctl & 0xfff4) | PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN;
-	pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl);
+	pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl);
 
 	pci_info(pdev, "error containment capabilities: Int Msg #%d, RPExt%c PoisonedTLP%c SwTrigger%c RP PIO Log %d, DL_ActiveErr%c\n",
 		 cap & PCI_EXP_DPC_IRQ, FLAG(cap, PCI_EXP_DPC_CAP_RP_EXT),
 		 FLAG(cap, PCI_EXP_DPC_CAP_POISONED_TLP),
-		 FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), dpc->rp_log_size,
+		 FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), pdev->dpc_rp_log_size,
 		 FLAG(cap, PCI_EXP_DPC_CAP_DL_ACTIVE));
 
 	pci_add_ext_cap_save_buffer(pdev, PCI_EXT_CAP_ID_DPC, sizeof(u16));
@@ -339,13 +299,12 @@ static int dpc_probe(struct pcie_device
 
 static void dpc_remove(struct pcie_device *dev)
 {
-	struct dpc_dev *dpc = get_service_data(dev);
 	struct pci_dev *pdev = dev->port;
 	u16 ctl;
 
-	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl);
+	pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl);
 	ctl &= ~(PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN);
-	pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl);
+	pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl);
 }
 
 static struct pcie_port_service_driver dpcdriver = {
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -445,6 +445,11 @@ struct pci_dev {
 	const struct attribute_group **msi_irq_groups;
 #endif
 	struct pci_vpd *vpd;
+#ifdef CONFIG_PCIE_DPC
+	u16		dpc_cap;
+	unsigned int	dpc_rp_extensions:1;
+	u8		dpc_rp_log_size;
+#endif
 #ifdef CONFIG_PCI_ATS
 	union {
 		struct pci_sriov	*sriov;		/* PF: SR-IOV info */