IOMMU Archive on lore.kernel.org
 help / color / Atom feed
WARNING: multiple messages have this Message-ID
From: Logan Gunthorpe <logang-OTvnGxWRz7hWk0Htik3J/w@public.gmane.org>
To: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-ntb-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org,
	linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org,
	linux-kselftest-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	Jon Mason <jdmason-zqedIHPRSYI@public.gmane.org>,
	Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Allen Hubbe <allenbh-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	Dave Jiang <dave.jiang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
	Serge Semin
	<fancer.lancer-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	Eric Pilmore <epilmore-Op3I1peydIbQT0dZR+AlfA@public.gmane.org>,
	Bjorn Helgaas <bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>,
	Logan Gunthorpe <logang-OTvnGxWRz7hWk0Htik3J/w@public.gmane.org>
Subject: [PATCH v4 03/10] NTB: Introduce helper functions to calculate logical port number
Date: Mon, 22 Apr 2019 15:05:21 -0600
Message-ID: <20190422210528.15289-4-logang@deltatee.com> (raw)
In-Reply-To: <20190422210528.15289-1-logang-OTvnGxWRz7hWk0Htik3J/w@public.gmane.org>

This patch introduces the "Logical Port Number" which is similar to the
"Port Number" in that it enumerates the ports in the system.

The original (or Physical) "Port Number" can be any number used by the
hardware to uniquely identify a port in the system. The "Logical Port
Number" enumerates all ports in the system from 0 to the number of
ports minus one.

For example a system with 5 ports might have the following port numbers
which would be enumerated thusly:

Port Number:           1  2  5  7  116
Logical Port Number:   0  1  2  3  4

The logical port number is useful when calculating which resources
to use for which peers. So we thus define two helper functions:
ntb_logical_port_number() and ntb_peer_logical_port_number() which
provide the "Logical Port Number" for the local port and any peer
respectively.

Signed-off-by: Logan Gunthorpe <logang-OTvnGxWRz7hWk0Htik3J/w@public.gmane.org>
Cc: Jon Mason <jdmason-zqedIHPRSYI@public.gmane.org>
Cc: Dave Jiang <dave.jiang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Cc: Allen Hubbe <allenbh-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Serge Semin <fancer.lancer-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
 include/linux/ntb.h | 53 ++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 52 insertions(+), 1 deletion(-)

diff --git a/include/linux/ntb.h b/include/linux/ntb.h
index 56a92e3ae3ae..91cf492b16a0 100644
--- a/include/linux/ntb.h
+++ b/include/linux/ntb.h
@@ -616,7 +616,6 @@ static inline int ntb_port_number(struct ntb_dev *ntb)
 
 	return ntb->ops->port_number(ntb);
 }
-
 /**
  * ntb_peer_port_count() - get the number of peer device ports
  * @ntb:	NTB device context.
@@ -653,6 +652,58 @@ static inline int ntb_peer_port_number(struct ntb_dev *ntb, int pidx)
 	return ntb->ops->peer_port_number(ntb, pidx);
 }
 
+/**
+ * ntb_logical_port_number() - get the logical port number of the local port
+ * @ntb:	NTB device context.
+ *
+ * The Logical Port Number is defined to be a unique number for each
+ * port starting from zero through to the number of ports minus one.
+ * This is in contrast to the Port Number where each port can be assigned
+ * any unique physical number by the hardware.
+ *
+ * The logical port number is useful for calculating the resource indexes
+ * used by peers.
+ *
+ * Return: the logical port number or negative value indicating an error
+ */
+static inline int ntb_logical_port_number(struct ntb_dev *ntb)
+{
+	int lport = ntb_port_number(ntb);
+	int pidx;
+
+	if (lport < 0)
+		return lport;
+
+	for (pidx = 0; pidx < ntb_peer_port_count(ntb); pidx++)
+		if (lport <= ntb_peer_port_number(ntb, pidx))
+			return pidx;
+
+	return pidx;
+}
+
+/**
+ * ntb_peer_logical_port_number() - get the logical peer port by given index
+ * @ntb:	NTB device context.
+ * @pidx:	Peer port index.
+ *
+ * The Logical Port Number is defined to be a unique number for each
+ * port starting from zero through to the number of ports minus one.
+ * This is in contrast to the Port Number where each port can be assigned
+ * any unique physical number by the hardware.
+ *
+ * The logical port number is useful for calculating the resource indexes
+ * used by peers.
+ *
+ * Return: the peer's logical port number or negative value indicating an error
+ */
+static inline int ntb_peer_logical_port_number(struct ntb_dev *ntb, int pidx)
+{
+	if (ntb_peer_port_number(ntb, pidx) < ntb_port_number(ntb))
+		return pidx;
+	else
+		return pidx + 1;
+}
+
 /**
  * ntb_peer_port_idx() - get the peer device port index by given port number
  * @ntb:	NTB device context.
-- 
2.20.1

From: Logan Gunthorpe <logang@deltatee.com>
To: linux-kernel@vger.kernel.org, linux-ntb@googlegroups.com,
	linux-pci@vger.kernel.org, iommu@lists.linux-foundation.org,
	linux-kselftest@vger.kernel.org, Jon Mason <jdmason@kudzu.us>,
	Joerg Roedel <joro@8bytes.org>
Cc: Allen Hubbe <allenbh@gmail.com>,
	Dave Jiang <dave.jiang@intel.com>,
	Serge Semin <fancer.lancer@gmail.com>,
	Eric Pilmore <epilmore@gigaio.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Logan Gunthorpe <logang@deltatee.com>
Subject: [PATCH v4 03/10] NTB: Introduce helper functions to calculate logical port number
Date: Mon, 22 Apr 2019 15:05:21 -0600
Message-ID: <20190422210528.15289-4-logang@deltatee.com> (raw)
Message-ID: <20190422210521.lsfNQtpvZEDRmCAZdlysAmSLX20u_0wiPqtSVAR2iKw@z> (raw)
In-Reply-To: <20190422210528.15289-1-logang@deltatee.com>

This patch introduces the "Logical Port Number" which is similar to the
"Port Number" in that it enumerates the ports in the system.

The original (or Physical) "Port Number" can be any number used by the
hardware to uniquely identify a port in the system. The "Logical Port
Number" enumerates all ports in the system from 0 to the number of
ports minus one.

For example a system with 5 ports might have the following port numbers
which would be enumerated thusly:

Port Number:           1  2  5  7  116
Logical Port Number:   0  1  2  3  4

The logical port number is useful when calculating which resources
to use for which peers. So we thus define two helper functions:
ntb_logical_port_number() and ntb_peer_logical_port_number() which
provide the "Logical Port Number" for the local port and any peer
respectively.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Jon Mason <jdmason@kudzu.us>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Allen Hubbe <allenbh@gmail.com>
Cc: Serge Semin <fancer.lancer@gmail.com>
---
 include/linux/ntb.h | 53 ++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 52 insertions(+), 1 deletion(-)

diff --git a/include/linux/ntb.h b/include/linux/ntb.h
index 56a92e3ae3ae..91cf492b16a0 100644
--- a/include/linux/ntb.h
+++ b/include/linux/ntb.h
@@ -616,7 +616,6 @@ static inline int ntb_port_number(struct ntb_dev *ntb)
 
 	return ntb->ops->port_number(ntb);
 }
-
 /**
  * ntb_peer_port_count() - get the number of peer device ports
  * @ntb:	NTB device context.
@@ -653,6 +652,58 @@ static inline int ntb_peer_port_number(struct ntb_dev *ntb, int pidx)
 	return ntb->ops->peer_port_number(ntb, pidx);
 }
 
+/**
+ * ntb_logical_port_number() - get the logical port number of the local port
+ * @ntb:	NTB device context.
+ *
+ * The Logical Port Number is defined to be a unique number for each
+ * port starting from zero through to the number of ports minus one.
+ * This is in contrast to the Port Number where each port can be assigned
+ * any unique physical number by the hardware.
+ *
+ * The logical port number is useful for calculating the resource indexes
+ * used by peers.
+ *
+ * Return: the logical port number or negative value indicating an error
+ */
+static inline int ntb_logical_port_number(struct ntb_dev *ntb)
+{
+	int lport = ntb_port_number(ntb);
+	int pidx;
+
+	if (lport < 0)
+		return lport;
+
+	for (pidx = 0; pidx < ntb_peer_port_count(ntb); pidx++)
+		if (lport <= ntb_peer_port_number(ntb, pidx))
+			return pidx;
+
+	return pidx;
+}
+
+/**
+ * ntb_peer_logical_port_number() - get the logical peer port by given index
+ * @ntb:	NTB device context.
+ * @pidx:	Peer port index.
+ *
+ * The Logical Port Number is defined to be a unique number for each
+ * port starting from zero through to the number of ports minus one.
+ * This is in contrast to the Port Number where each port can be assigned
+ * any unique physical number by the hardware.
+ *
+ * The logical port number is useful for calculating the resource indexes
+ * used by peers.
+ *
+ * Return: the peer's logical port number or negative value indicating an error
+ */
+static inline int ntb_peer_logical_port_number(struct ntb_dev *ntb, int pidx)
+{
+	if (ntb_peer_port_number(ntb, pidx) < ntb_port_number(ntb))
+		return pidx;
+	else
+		return pidx + 1;
+}
+
 /**
  * ntb_peer_port_idx() - get the peer device port index by given port number
  * @ntb:	NTB device context.
-- 
2.20.1

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

  parent reply index

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-22 21:05 [PATCH v4 00/10] Support using MSI interrupts in ntb_transport Logan Gunthorpe
2019-04-22 21:05 ` Logan Gunthorpe
     [not found] ` <20190422210528.15289-1-logang-OTvnGxWRz7hWk0Htik3J/w@public.gmane.org>
2019-04-22 21:05   ` [PATCH v4 01/10] PCI/MSI: Support allocating virtual MSI interrupts Logan Gunthorpe
2019-04-22 21:05     ` Logan Gunthorpe
2019-04-22 21:05   ` [PATCH v4 02/10] PCI/switchtec: Add module parameter to request more interrupts Logan Gunthorpe
2019-04-22 21:05     ` Logan Gunthorpe
2019-04-22 21:05   ` Logan Gunthorpe [this message]
2019-04-22 21:05     ` [PATCH v4 03/10] NTB: Introduce helper functions to calculate logical port number Logan Gunthorpe
2019-04-22 21:05   ` [PATCH v4 04/10] NTB: Introduce functions to calculate multi-port resource index Logan Gunthorpe
2019-04-22 21:05     ` Logan Gunthorpe
2019-04-22 21:05   ` [PATCH v4 08/10] NTB: Add ntb_msi_test support to ntb_test Logan Gunthorpe
2019-04-22 21:05     ` Logan Gunthorpe
2019-04-22 21:05 ` [PATCH v4 05/10] NTB: Rename ntb.c to support multiple source files in the module Logan Gunthorpe
2019-04-22 21:05   ` Logan Gunthorpe
2019-04-22 21:05 ` [PATCH v4 06/10] NTB: Introduce MSI library Logan Gunthorpe
2019-04-22 21:05   ` Logan Gunthorpe
2019-04-22 21:05 ` [PATCH v4 07/10] NTB: Introduce NTB MSI Test Client Logan Gunthorpe
2019-04-22 21:05   ` Logan Gunthorpe
2019-04-22 21:05 ` [PATCH v4 09/10] NTB: Add MSI interrupt support to ntb_transport Logan Gunthorpe
2019-04-22 21:05   ` Logan Gunthorpe
2019-04-22 21:05 ` [PATCH v4 10/10] NTB: Describe the ntb_msi_test client in the documentation Logan Gunthorpe
2019-04-22 21:05   ` Logan Gunthorpe

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190422210528.15289-4-logang@deltatee.com \
    --to=logang-otvngxwrz7hwk0htik3j/w@public.gmane.org \
    --cc=allenbh-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \
    --cc=bhelgaas-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org \
    --cc=dave.jiang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org \
    --cc=epilmore-Op3I1peydIbQT0dZR+AlfA@public.gmane.org \
    --cc=fancer.lancer-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \
    --cc=iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org \
    --cc=jdmason-zqedIHPRSYI@public.gmane.org \
    --cc=joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org \
    --cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=linux-kselftest-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=linux-ntb-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org \
    --cc=linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

IOMMU Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-iommu/0 linux-iommu/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-iommu linux-iommu/ https://lore.kernel.org/linux-iommu \
		iommu@lists.linux-foundation.org
	public-inbox-index linux-iommu

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.linux-foundation.lists.iommu


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git