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From: Wei Yang <weiyang@linux.vnet.ibm.com>
To: gwshan@linux.vnet.ibm.com, bhelgaas@google.com
Cc: linuxppc-dev@lists.ozlabs.org, linux-pci@vger.kernel.org,
	Wei Yang <weiyang@linux.vnet.ibm.com>
Subject: [PATCH V7 07/10] powerpc/powernv: Support EEH reset for VF PE
Date: Tue, 19 May 2015 18:50:09 +0800	[thread overview]
Message-ID: <1432032612-21701-8-git-send-email-weiyang@linux.vnet.ibm.com> (raw)
In-Reply-To: <1432032612-21701-1-git-send-email-weiyang@linux.vnet.ibm.com>

PEs for VFs don't have primary bus. So they have to have their own reset
backend, which is used during EEH recovery. The patch implements the reset
backend for VF's PE by issuing FLR or AF FLR to the VFs, which are contained
in the PE.

[gwshan: changelog and code refactoring]
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/eeh.h               |    1 +
 arch/powerpc/platforms/powernv/eeh-powernv.c |  134 +++++++++++++++++++++++++-
 2 files changed, 134 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index c1fde48..3d64cf3 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -134,6 +134,7 @@ struct eeh_dev {
 	int pcix_cap;			/* Saved PCIx capability	*/
 	int pcie_cap;			/* Saved PCIe capability	*/
 	int aer_cap;			/* Saved AER capability		*/
+	int af_cap;			/* Saved AF capability		*/
 	struct eeh_pe *pe;		/* Associated PE		*/
 	struct list_head list;		/* Form link list in the PE	*/
 	struct pci_controller *phb;	/* Associated PHB		*/
diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c
index c505036..7af3c1e 100644
--- a/arch/powerpc/platforms/powernv/eeh-powernv.c
+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c
@@ -402,6 +402,7 @@ static void *pnv_eeh_probe(struct pci_dn *pdn, void *data)
 	edev->pcix_cap = pnv_eeh_find_cap(pdn, PCI_CAP_ID_PCIX);
 	edev->pcie_cap = pnv_eeh_find_cap(pdn, PCI_CAP_ID_EXP);
 	edev->aer_cap  = pnv_eeh_find_ecap(pdn, PCI_EXT_CAP_ID_ERR);
+	edev->af_cap   = pnv_eeh_find_cap(pdn, PCI_CAP_ID_AF);
 	if ((edev->class_code >> 8) == PCI_CLASS_BRIDGE_PCI) {
 		edev->mode |= EEH_DEV_BRIDGE;
 		if (edev->pcie_cap) {
@@ -891,6 +892,127 @@ static int pnv_eeh_bridge_reset(struct pci_dev *dev, int option)
 	return 0;
 }
 
+static void pnv_eeh_wait_for_pending(struct pci_dn *pdn, int pos,
+				     u16 mask, bool af_flr_rst)
+{
+	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+	int status, i;
+
+	/* Wait for Transaction Pending bit to be cleared */
+	for (i = 0; i < 4; i++) {
+		eeh_ops->read_config(pdn, pos, 2, &status);
+		if (!(status & mask))
+			return;
+
+		msleep((1 << i) * 100);
+	}
+
+	pr_warn("%s: Pending transaction while issuing %s FLR to "
+		"%04x:%02x:%02x.%01x\n",
+		__func__, af_flr_rst ? "AF" : "",
+		edev->phb->global_number, pdn->busno,
+		PCI_SLOT(pdn->devfn), PCI_FUNC(pdn->devfn));
+}
+
+static int pnv_eeh_do_flr(struct pci_dn *pdn, int option)
+{
+	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+	u32 reg;
+
+	if (!edev->pcie_cap)
+		return -ENOTTY;
+
+	eeh_ops->read_config(pdn, edev->pcie_cap + PCI_EXP_DEVCAP, 4, &reg);
+	if (!(reg & PCI_EXP_DEVCAP_FLR))
+		return -ENOTTY;
+
+	switch (option) {
+	case EEH_RESET_HOT:
+	case EEH_RESET_FUNDAMENTAL:
+		pnv_eeh_wait_for_pending(pdn, edev->pcie_cap + PCI_EXP_DEVSTA,
+					 PCI_EXP_DEVSTA_TRPND, false);
+		eeh_ops->read_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+				     4, &reg);
+		reg |= PCI_EXP_DEVCTL_BCR_FLR;
+		eeh_ops->write_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+				      4, reg);
+		msleep(EEH_PE_RST_HOLD_TIME);
+		break;
+	case EEH_RESET_DEACTIVATE:
+		eeh_ops->read_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+				     4, &reg);
+		reg &= ~PCI_EXP_DEVCTL_BCR_FLR;
+		eeh_ops->write_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+				      4, reg);
+		msleep(EEH_PE_RST_SETTLE_TIME);
+		break;
+	}
+
+	return 0;
+}
+
+static int pnv_eeh_do_af_flr(struct pci_dn *pdn, int option)
+{
+	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+	u32 cap;
+
+	if (!edev->af_cap)
+		return -ENOTTY;
+
+	eeh_ops->read_config(pdn, edev->af_cap + PCI_AF_CAP, 1, &cap);
+	if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
+		return -ENOTTY;
+
+	switch (option) {
+	case EEH_RESET_HOT:
+	case EEH_RESET_FUNDAMENTAL:
+		/*
+		 * Wait for Transaction Pending bit to clear. A word-aligned
+		 * test is used, so we use the conrol offset rather than status
+		 * and shift the test bit to match.
+		 */
+		pnv_eeh_wait_for_pending(pdn, edev->af_cap + PCI_AF_CTRL,
+					 PCI_AF_STATUS_TP << 8, true);
+		eeh_ops->write_config(pdn, edev->af_cap + PCI_AF_CTRL,
+				      1, PCI_AF_CTRL_FLR);
+		msleep(EEH_PE_RST_HOLD_TIME);
+		break;
+	case EEH_RESET_DEACTIVATE:
+		eeh_ops->write_config(pdn, edev->af_cap + PCI_AF_CTRL, 1, 0);
+		msleep(EEH_PE_RST_SETTLE_TIME);
+		break;
+	}
+
+	return 0;
+}
+
+static int pnv_eeh_reset_vf(struct pci_dn *pdn, int option)
+{
+	int ret;
+
+	ret = pnv_eeh_do_flr(pdn, option);
+	if (ret)
+		return ret;
+
+	return pnv_eeh_do_af_flr(pdn, option);
+}
+
+static int pnv_eeh_vf_pe_reset(struct eeh_pe *pe, int option)
+{
+	struct eeh_dev *edev, *tmp;
+	struct pci_dn *pdn;
+	int ret;
+
+	eeh_pe_for_each_dev(pe, edev, tmp) {
+		pdn = eeh_dev_to_pdn(edev);
+		ret = pnv_eeh_reset_vf(pdn, option);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 void pnv_pci_reset_secondary_bus(struct pci_dev *dev)
 {
 	struct pci_controller *hose;
@@ -966,7 +1088,9 @@ static int pnv_eeh_reset(struct eeh_pe *pe, int option)
 		}
 
 		bus = eeh_pe_bus_get(pe);
-		if (pci_is_root_bus(bus) ||
+		if (pe->type & EEH_PE_VF)
+			ret = pnv_eeh_vf_pe_reset(pe, option);
+		else if (pci_is_root_bus(bus) ||
 			pci_is_root_bus(bus->parent))
 			ret = pnv_eeh_root_reset(hose, option);
 		else
@@ -1106,6 +1230,14 @@ static inline bool pnv_eeh_cfg_blocked(struct pci_dn *pdn)
 	if (!edev || !edev->pe)
 		return false;
 
+	/*
+	 * We will issue FLR or AF FLR to all VFs, which are contained
+	 * in VF PE. It relies on the EEH PCI config accessors. So we
+	 * can't block them during the window.
+	 */
+	if ((edev->physfn) && (edev->pe->state & EEH_PE_RESET))
+		return false;
+
 	if (edev->pe->state & EEH_PE_CFG_BLOCKED)
 		return true;
 
-- 
1.7.9.5


WARNING: multiple messages have this Message-ID (diff)
From: Wei Yang <weiyang@linux.vnet.ibm.com>
To: gwshan@linux.vnet.ibm.com, bhelgaas@google.com
Cc: linux-pci@vger.kernel.org, Wei Yang <weiyang@linux.vnet.ibm.com>,
	linuxppc-dev@lists.ozlabs.org
Subject: [PATCH V7 07/10] powerpc/powernv: Support EEH reset for VF PE
Date: Tue, 19 May 2015 18:50:09 +0800	[thread overview]
Message-ID: <1432032612-21701-8-git-send-email-weiyang@linux.vnet.ibm.com> (raw)
In-Reply-To: <1432032612-21701-1-git-send-email-weiyang@linux.vnet.ibm.com>

PEs for VFs don't have primary bus. So they have to have their own reset
backend, which is used during EEH recovery. The patch implements the reset
backend for VF's PE by issuing FLR or AF FLR to the VFs, which are contained
in the PE.

[gwshan: changelog and code refactoring]
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/eeh.h               |    1 +
 arch/powerpc/platforms/powernv/eeh-powernv.c |  134 +++++++++++++++++++++++++-
 2 files changed, 134 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index c1fde48..3d64cf3 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -134,6 +134,7 @@ struct eeh_dev {
 	int pcix_cap;			/* Saved PCIx capability	*/
 	int pcie_cap;			/* Saved PCIe capability	*/
 	int aer_cap;			/* Saved AER capability		*/
+	int af_cap;			/* Saved AF capability		*/
 	struct eeh_pe *pe;		/* Associated PE		*/
 	struct list_head list;		/* Form link list in the PE	*/
 	struct pci_controller *phb;	/* Associated PHB		*/
diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c
index c505036..7af3c1e 100644
--- a/arch/powerpc/platforms/powernv/eeh-powernv.c
+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c
@@ -402,6 +402,7 @@ static void *pnv_eeh_probe(struct pci_dn *pdn, void *data)
 	edev->pcix_cap = pnv_eeh_find_cap(pdn, PCI_CAP_ID_PCIX);
 	edev->pcie_cap = pnv_eeh_find_cap(pdn, PCI_CAP_ID_EXP);
 	edev->aer_cap  = pnv_eeh_find_ecap(pdn, PCI_EXT_CAP_ID_ERR);
+	edev->af_cap   = pnv_eeh_find_cap(pdn, PCI_CAP_ID_AF);
 	if ((edev->class_code >> 8) == PCI_CLASS_BRIDGE_PCI) {
 		edev->mode |= EEH_DEV_BRIDGE;
 		if (edev->pcie_cap) {
@@ -891,6 +892,127 @@ static int pnv_eeh_bridge_reset(struct pci_dev *dev, int option)
 	return 0;
 }
 
+static void pnv_eeh_wait_for_pending(struct pci_dn *pdn, int pos,
+				     u16 mask, bool af_flr_rst)
+{
+	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+	int status, i;
+
+	/* Wait for Transaction Pending bit to be cleared */
+	for (i = 0; i < 4; i++) {
+		eeh_ops->read_config(pdn, pos, 2, &status);
+		if (!(status & mask))
+			return;
+
+		msleep((1 << i) * 100);
+	}
+
+	pr_warn("%s: Pending transaction while issuing %s FLR to "
+		"%04x:%02x:%02x.%01x\n",
+		__func__, af_flr_rst ? "AF" : "",
+		edev->phb->global_number, pdn->busno,
+		PCI_SLOT(pdn->devfn), PCI_FUNC(pdn->devfn));
+}
+
+static int pnv_eeh_do_flr(struct pci_dn *pdn, int option)
+{
+	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+	u32 reg;
+
+	if (!edev->pcie_cap)
+		return -ENOTTY;
+
+	eeh_ops->read_config(pdn, edev->pcie_cap + PCI_EXP_DEVCAP, 4, &reg);
+	if (!(reg & PCI_EXP_DEVCAP_FLR))
+		return -ENOTTY;
+
+	switch (option) {
+	case EEH_RESET_HOT:
+	case EEH_RESET_FUNDAMENTAL:
+		pnv_eeh_wait_for_pending(pdn, edev->pcie_cap + PCI_EXP_DEVSTA,
+					 PCI_EXP_DEVSTA_TRPND, false);
+		eeh_ops->read_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+				     4, &reg);
+		reg |= PCI_EXP_DEVCTL_BCR_FLR;
+		eeh_ops->write_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+				      4, reg);
+		msleep(EEH_PE_RST_HOLD_TIME);
+		break;
+	case EEH_RESET_DEACTIVATE:
+		eeh_ops->read_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+				     4, &reg);
+		reg &= ~PCI_EXP_DEVCTL_BCR_FLR;
+		eeh_ops->write_config(pdn, edev->pcie_cap + PCI_EXP_DEVCTL,
+				      4, reg);
+		msleep(EEH_PE_RST_SETTLE_TIME);
+		break;
+	}
+
+	return 0;
+}
+
+static int pnv_eeh_do_af_flr(struct pci_dn *pdn, int option)
+{
+	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+	u32 cap;
+
+	if (!edev->af_cap)
+		return -ENOTTY;
+
+	eeh_ops->read_config(pdn, edev->af_cap + PCI_AF_CAP, 1, &cap);
+	if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
+		return -ENOTTY;
+
+	switch (option) {
+	case EEH_RESET_HOT:
+	case EEH_RESET_FUNDAMENTAL:
+		/*
+		 * Wait for Transaction Pending bit to clear. A word-aligned
+		 * test is used, so we use the conrol offset rather than status
+		 * and shift the test bit to match.
+		 */
+		pnv_eeh_wait_for_pending(pdn, edev->af_cap + PCI_AF_CTRL,
+					 PCI_AF_STATUS_TP << 8, true);
+		eeh_ops->write_config(pdn, edev->af_cap + PCI_AF_CTRL,
+				      1, PCI_AF_CTRL_FLR);
+		msleep(EEH_PE_RST_HOLD_TIME);
+		break;
+	case EEH_RESET_DEACTIVATE:
+		eeh_ops->write_config(pdn, edev->af_cap + PCI_AF_CTRL, 1, 0);
+		msleep(EEH_PE_RST_SETTLE_TIME);
+		break;
+	}
+
+	return 0;
+}
+
+static int pnv_eeh_reset_vf(struct pci_dn *pdn, int option)
+{
+	int ret;
+
+	ret = pnv_eeh_do_flr(pdn, option);
+	if (ret)
+		return ret;
+
+	return pnv_eeh_do_af_flr(pdn, option);
+}
+
+static int pnv_eeh_vf_pe_reset(struct eeh_pe *pe, int option)
+{
+	struct eeh_dev *edev, *tmp;
+	struct pci_dn *pdn;
+	int ret;
+
+	eeh_pe_for_each_dev(pe, edev, tmp) {
+		pdn = eeh_dev_to_pdn(edev);
+		ret = pnv_eeh_reset_vf(pdn, option);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 void pnv_pci_reset_secondary_bus(struct pci_dev *dev)
 {
 	struct pci_controller *hose;
@@ -966,7 +1088,9 @@ static int pnv_eeh_reset(struct eeh_pe *pe, int option)
 		}
 
 		bus = eeh_pe_bus_get(pe);
-		if (pci_is_root_bus(bus) ||
+		if (pe->type & EEH_PE_VF)
+			ret = pnv_eeh_vf_pe_reset(pe, option);
+		else if (pci_is_root_bus(bus) ||
 			pci_is_root_bus(bus->parent))
 			ret = pnv_eeh_root_reset(hose, option);
 		else
@@ -1106,6 +1230,14 @@ static inline bool pnv_eeh_cfg_blocked(struct pci_dn *pdn)
 	if (!edev || !edev->pe)
 		return false;
 
+	/*
+	 * We will issue FLR or AF FLR to all VFs, which are contained
+	 * in VF PE. It relies on the EEH PCI config accessors. So we
+	 * can't block them during the window.
+	 */
+	if ((edev->physfn) && (edev->pe->state & EEH_PE_RESET))
+		return false;
+
 	if (edev->pe->state & EEH_PE_CFG_BLOCKED)
 		return true;
 
-- 
1.7.9.5

  parent reply	other threads:[~2015-05-19 10:55 UTC|newest]

Thread overview: 68+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-05-19  1:35 [PATCH V6 00/10] VF EEH on Power8 Wei Yang
2015-05-19  1:35 ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 01/10] PCI/IOV: Rename and export virtfn_add/virtfn_remove Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19  5:24   ` Wei Yang
2015-05-19  5:24     ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 02/10] powerpc/pci: Cache VF index in pci_dn Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 03/10] powerpc/pci: Remove VFs prior to PF Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 04/10] powerpc/eeh: Trace first 7 BARs in address cache Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 05/10] powerpc/powernv: EEH device for VF Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 06/10] powerpc/eeh: Create PE for VFs Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 07/10] powerpc/powernv: Support EEH reset for VF PE Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 08/10] powerpc/powernv: Support PCI config restore for VFs Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 09/10] powerpc/eeh: Support error recovery for VF PE Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19  1:35 ` [PATCH V6 10/10] powerpc/powernv: compound PE for VFs Wei Yang
2015-05-19  1:35   ` Wei Yang
2015-05-19 10:50 ` [PATCH V7 00/10] VF EEH on Power8 Wei Yang
2015-05-19 10:50   ` Wei Yang
2015-05-19 10:50   ` [PATCH V7 01/10] PCI/IOV: Rename and export virtfn_add/virtfn_remove Wei Yang
2015-05-19 10:50     ` Wei Yang
2015-06-02 17:19     ` Bjorn Helgaas
2015-06-03  1:38       ` Wei Yang
2015-05-19 10:50   ` [PATCH V7 02/10] powerpc/pci: Cache VF index in pci_dn Wei Yang
2015-05-19 10:50     ` Wei Yang
2015-05-19 10:50   ` [PATCH V7 03/10] powerpc/pci: Remove VFs prior to PF Wei Yang
2015-05-19 10:50     ` Wei Yang
2015-06-01 23:20     ` Bjorn Helgaas
2015-06-02  3:44       ` Wei Yang
2015-05-19 10:50   ` [PATCH V7 04/10] powerpc/eeh: Trace first 7 BARs in address cache Wei Yang
2015-05-19 10:50     ` Wei Yang
2015-06-01 23:32     ` Bjorn Helgaas
2015-06-02  3:51       ` Wei Yang
2015-06-02  4:11         ` Gavin Shan
2015-06-03  1:47           ` Wei Yang
2015-05-19 10:50   ` [PATCH V7 05/10] powerpc/powernv: EEH device for VF Wei Yang
2015-05-19 10:50     ` Wei Yang
2015-05-19 10:50   ` [PATCH V7 06/10] powerpc/eeh: Create PE for VFs Wei Yang
2015-05-19 10:50     ` Wei Yang
2015-06-01 23:46     ` Bjorn Helgaas
2015-06-03  3:31       ` Wei Yang
2015-06-03  5:10         ` Gavin Shan
2015-06-03 15:46           ` Bjorn Helgaas
2015-06-04  1:25             ` Gavin Shan
2015-06-04  5:46             ` Wei Yang
2015-06-04  7:10               ` Gavin Shan
2015-06-16  8:50             ` Wei Yang
2015-06-16 13:22               ` Bjorn Helgaas
2015-06-01 23:49     ` Bjorn Helgaas
2015-06-03  3:39       ` Wei Yang
2015-05-19 10:50   ` Wei Yang [this message]
2015-05-19 10:50     ` [PATCH V7 07/10] powerpc/powernv: Support EEH reset for VF PE Wei Yang
2015-05-19 10:50   ` [PATCH V7 08/10] powerpc/powernv: Support PCI config restore for VFs Wei Yang
2015-05-19 10:50     ` Wei Yang
2015-06-02  0:01     ` Bjorn Helgaas
2015-06-03  1:37       ` Wei Yang
2015-06-03  5:14         ` Gavin Shan
2015-05-19 10:50   ` [PATCH V7 09/10] powerpc/eeh: Support error recovery for VF PE Wei Yang
2015-05-19 10:50     ` Wei Yang
2015-05-19 10:50   ` [PATCH V7 10/10] powerpc/powernv: compound PE for VFs Wei Yang
2015-05-19 10:50     ` Wei Yang

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