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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /drivers/net/arcnet/capmode.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'drivers/net/arcnet/capmode.c')
-rw-r--r--drivers/net/arcnet/capmode.c269
1 files changed, 269 insertions, 0 deletions
diff --git a/drivers/net/arcnet/capmode.c b/drivers/net/arcnet/capmode.c
new file mode 100644
index 000000000..7a0a79973
--- /dev/null
+++ b/drivers/net/arcnet/capmode.c
@@ -0,0 +1,269 @@
+/*
+ * Linux ARCnet driver - "cap mode" packet encapsulation.
+ * It adds sequence numbers to packets for communicating between a user space
+ * application and the driver. After a transmit it sends a packet with protocol
+ * byte 0 back up to the userspace containing the sequence number of the packet
+ * plus the transmit-status on the ArcNet.
+ *
+ * Written 2002-4 by Esben Nielsen, Vestas Wind Systems A/S
+ * Derived from arc-rawmode.c by Avery Pennarun.
+ * arc-rawmode was in turned based on skeleton.c, see below.
+ *
+ * **********************
+ *
+ * The original copyright of skeleton.c was as follows:
+ *
+ * skeleton.c Written 1993 by Donald Becker.
+ * Copyright 1993 United States Government as represented by the
+ * Director, National Security Agency. This software may only be used
+ * and distributed according to the terms of the GNU General Public License as
+ * modified by SRC, incorporated herein by reference.
+ *
+ * **********************
+ *
+ * For more details, see drivers/net/arcnet.c
+ *
+ * **********************
+ */
+
+#define pr_fmt(fmt) "arcnet:" KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/gfp.h>
+#include <linux/init.h>
+#include <linux/if_arp.h>
+#include <net/arp.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+
+#include "arcdevice.h"
+
+/* packet receiver */
+static void rx(struct net_device *dev, int bufnum,
+ struct archdr *pkthdr, int length)
+{
+ struct arcnet_local *lp = netdev_priv(dev);
+ struct sk_buff *skb;
+ struct archdr *pkt;
+ char *pktbuf, *pkthdrbuf;
+ int ofs;
+
+ arc_printk(D_DURING, dev, "it's a raw(cap) packet (length=%d)\n",
+ length);
+
+ if (length >= MinTU)
+ ofs = 512 - length;
+ else
+ ofs = 256 - length;
+
+ skb = alloc_skb(length + ARC_HDR_SIZE + sizeof(int), GFP_ATOMIC);
+ if (!skb) {
+ dev->stats.rx_dropped++;
+ return;
+ }
+ skb_put(skb, length + ARC_HDR_SIZE + sizeof(int));
+ skb->dev = dev;
+ skb_reset_mac_header(skb);
+ pkt = (struct archdr *)skb_mac_header(skb);
+ skb_pull(skb, ARC_HDR_SIZE);
+
+ /* up to sizeof(pkt->soft) has already been copied from the card
+ * squeeze in an int for the cap encapsulation
+ * use these variables to be sure we count in bytes, not in
+ * sizeof(struct archdr)
+ */
+ pktbuf = (char *)pkt;
+ pkthdrbuf = (char *)pkthdr;
+ memcpy(pktbuf, pkthdrbuf, ARC_HDR_SIZE + sizeof(pkt->soft.cap.proto));
+ memcpy(pktbuf + ARC_HDR_SIZE + sizeof(pkt->soft.cap.proto) + sizeof(int),
+ pkthdrbuf + ARC_HDR_SIZE + sizeof(pkt->soft.cap.proto),
+ sizeof(struct archdr) - ARC_HDR_SIZE - sizeof(pkt->soft.cap.proto));
+
+ if (length > sizeof(pkt->soft))
+ lp->hw.copy_from_card(dev, bufnum, ofs + sizeof(pkt->soft),
+ pkt->soft.raw + sizeof(pkt->soft)
+ + sizeof(int),
+ length - sizeof(pkt->soft));
+
+ if (BUGLVL(D_SKB))
+ arcnet_dump_skb(dev, skb, "rx");
+
+ skb->protocol = cpu_to_be16(ETH_P_ARCNET);
+ netif_rx(skb);
+}
+
+/* Create the ARCnet hard/soft headers for cap mode.
+ * There aren't any soft headers in cap mode - not even the protocol id.
+ */
+static int build_header(struct sk_buff *skb,
+ struct net_device *dev,
+ unsigned short type,
+ uint8_t daddr)
+{
+ int hdr_size = ARC_HDR_SIZE;
+ struct archdr *pkt = skb_push(skb, hdr_size);
+
+ arc_printk(D_PROTO, dev, "Preparing header for cap packet %x.\n",
+ *((int *)&pkt->soft.cap.cookie[0]));
+
+ /* Set the source hardware address.
+ *
+ * This is pretty pointless for most purposes, but it can help in
+ * debugging. ARCnet does not allow us to change the source address in
+ * the actual packet sent)
+ */
+ pkt->hard.source = *dev->dev_addr;
+
+ /* see linux/net/ethernet/eth.c to see where I got the following */
+
+ if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
+ /* FIXME: fill in the last byte of the dest ipaddr here to
+ * better comply with RFC1051 in "noarp" mode.
+ */
+ pkt->hard.dest = 0;
+ return hdr_size;
+ }
+ /* otherwise, just fill it in and go! */
+ pkt->hard.dest = daddr;
+
+ return hdr_size; /* success */
+}
+
+static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
+ int bufnum)
+{
+ struct arcnet_local *lp = netdev_priv(dev);
+ struct arc_hardware *hard = &pkt->hard;
+ int ofs;
+
+ /* hard header is not included in packet length */
+ length -= ARC_HDR_SIZE;
+ /* And neither is the cookie field */
+ length -= sizeof(int);
+
+ arc_printk(D_DURING, dev, "prepare_tx: txbufs=%d/%d/%d\n",
+ lp->next_tx, lp->cur_tx, bufnum);
+
+ arc_printk(D_PROTO, dev, "Sending for cap packet %x.\n",
+ *((int *)&pkt->soft.cap.cookie[0]));
+
+ if (length > XMTU) {
+ /* should never happen! other people already check for this. */
+ arc_printk(D_NORMAL, dev, "Bug! prepare_tx with size %d (> %d)\n",
+ length, XMTU);
+ length = XMTU;
+ }
+ if (length > MinTU) {
+ hard->offset[0] = 0;
+ hard->offset[1] = ofs = 512 - length;
+ } else if (length > MTU) {
+ hard->offset[0] = 0;
+ hard->offset[1] = ofs = 512 - length - 3;
+ } else {
+ hard->offset[0] = ofs = 256 - length;
+ }
+
+ arc_printk(D_DURING, dev, "prepare_tx: length=%d ofs=%d\n",
+ length, ofs);
+
+ /* Copy the arcnet-header + the protocol byte down: */
+ lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE);
+ lp->hw.copy_to_card(dev, bufnum, ofs, &pkt->soft.cap.proto,
+ sizeof(pkt->soft.cap.proto));
+
+ /* Skip the extra integer we have written into it as a cookie
+ * but write the rest of the message:
+ */
+ lp->hw.copy_to_card(dev, bufnum, ofs + 1,
+ ((unsigned char *)&pkt->soft.cap.mes), length - 1);
+
+ lp->lastload_dest = hard->dest;
+
+ return 1; /* done */
+}
+
+static int ack_tx(struct net_device *dev, int acked)
+{
+ struct arcnet_local *lp = netdev_priv(dev);
+ struct sk_buff *ackskb;
+ struct archdr *ackpkt;
+ int length = sizeof(struct arc_cap);
+
+ arc_printk(D_DURING, dev, "capmode: ack_tx: protocol: %x: result: %d\n",
+ lp->outgoing.skb->protocol, acked);
+
+ if (BUGLVL(D_SKB))
+ arcnet_dump_skb(dev, lp->outgoing.skb, "ack_tx");
+
+ /* Now alloc a skb to send back up through the layers: */
+ ackskb = alloc_skb(length + ARC_HDR_SIZE, GFP_ATOMIC);
+ if (!ackskb)
+ goto free_outskb;
+
+ skb_put(ackskb, length + ARC_HDR_SIZE);
+ ackskb->dev = dev;
+
+ skb_reset_mac_header(ackskb);
+ ackpkt = (struct archdr *)skb_mac_header(ackskb);
+ /* skb_pull(ackskb, ARC_HDR_SIZE); */
+
+ skb_copy_from_linear_data(lp->outgoing.skb, ackpkt,
+ ARC_HDR_SIZE + sizeof(struct arc_cap));
+ ackpkt->soft.cap.proto = 0; /* using protocol 0 for acknowledge */
+ ackpkt->soft.cap.mes.ack = acked;
+
+ arc_printk(D_PROTO, dev, "Acknowledge for cap packet %x.\n",
+ *((int *)&ackpkt->soft.cap.cookie[0]));
+
+ ackskb->protocol = cpu_to_be16(ETH_P_ARCNET);
+
+ if (BUGLVL(D_SKB))
+ arcnet_dump_skb(dev, ackskb, "ack_tx_recv");
+ netif_rx(ackskb);
+
+free_outskb:
+ dev_kfree_skb_irq(lp->outgoing.skb);
+ lp->outgoing.proto = NULL;
+ /* We are always finished when in this protocol */
+
+ return 0;
+}
+
+static struct ArcProto capmode_proto = {
+ .suffix = 'r',
+ .mtu = XMTU,
+ .rx = rx,
+ .build_header = build_header,
+ .prepare_tx = prepare_tx,
+ .ack_tx = ack_tx
+};
+
+static int __init capmode_module_init(void)
+{
+ int count;
+
+ pr_info("cap mode (`c') encapsulation support loaded\n");
+
+ for (count = 1; count <= 8; count++)
+ if (arc_proto_map[count] == arc_proto_default)
+ arc_proto_map[count] = &capmode_proto;
+
+ /* for cap mode, we only set the bcast proto if there's no better one */
+ if (arc_bcast_proto == arc_proto_default)
+ arc_bcast_proto = &capmode_proto;
+
+ arc_proto_default = &capmode_proto;
+ arc_raw_proto = &capmode_proto;
+
+ return 0;
+}
+
+static void __exit capmode_module_exit(void)
+{
+ arcnet_unregister_proto(&capmode_proto);
+}
+module_init(capmode_module_init);
+module_exit(capmode_module_exit);
+
+MODULE_DESCRIPTION("ARCnet CAP mode packet interface module");
+MODULE_LICENSE("GPL");