linux/drivers/scsi/fcoe/libfcoe.c
Yi Zou 07c00ec449 [SCSI] fcoe: fcoe fc crc offload indication by skb->ip_summed
If LLD supports FCCRC offload, it should set ip_summed to be
CHECKSUM_UNNECESSARY so we don't have to do CRC check again.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:15:48 -05:00

1475 lines
35 KiB
C

/*
* Copyright(c) 2007 - 2008 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
* Maintained at www.Open-FCoE.org
*/
#include <linux/module.h>
#include <linux/version.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/kthread.h>
#include <linux/crc32.h>
#include <linux/cpu.h>
#include <linux/fs.h>
#include <linux/sysfs.h>
#include <linux/ctype.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsicam.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_fc.h>
#include <net/rtnetlink.h>
#include <scsi/fc/fc_encaps.h>
#include <scsi/libfc.h>
#include <scsi/fc_frame.h>
#include <scsi/libfcoe.h>
#include <scsi/fc_transport_fcoe.h>
static int debug_fcoe;
#define FCOE_MAX_QUEUE_DEPTH 256
#define FCOE_LOW_QUEUE_DEPTH 32
/* destination address mode */
#define FCOE_GW_ADDR_MODE 0x00
#define FCOE_FCOUI_ADDR_MODE 0x01
#define FCOE_WORD_TO_BYTE 4
MODULE_AUTHOR("Open-FCoE.org");
MODULE_DESCRIPTION("FCoE");
MODULE_LICENSE("GPL");
/* fcoe host list */
LIST_HEAD(fcoe_hostlist);
DEFINE_RWLOCK(fcoe_hostlist_lock);
DEFINE_TIMER(fcoe_timer, NULL, 0, 0);
struct fcoe_percpu_s *fcoe_percpu[NR_CPUS];
/* Function Prototyes */
static int fcoe_check_wait_queue(struct fc_lport *);
static void fcoe_recv_flogi(struct fcoe_softc *, struct fc_frame *, u8 *);
#ifdef CONFIG_HOTPLUG_CPU
static int fcoe_cpu_callback(struct notifier_block *, ulong, void *);
#endif /* CONFIG_HOTPLUG_CPU */
static int fcoe_device_notification(struct notifier_block *, ulong, void *);
static void fcoe_dev_setup(void);
static void fcoe_dev_cleanup(void);
/* notification function from net device */
static struct notifier_block fcoe_notifier = {
.notifier_call = fcoe_device_notification,
};
#ifdef CONFIG_HOTPLUG_CPU
static struct notifier_block fcoe_cpu_notifier = {
.notifier_call = fcoe_cpu_callback,
};
/**
* fcoe_create_percpu_data() - creates the associated cpu data
* @cpu: index for the cpu where fcoe cpu data will be created
*
* create percpu stats block, from cpu add notifier
*
* Returns: none
*/
static void fcoe_create_percpu_data(int cpu)
{
struct fc_lport *lp;
struct fcoe_softc *fc;
write_lock_bh(&fcoe_hostlist_lock);
list_for_each_entry(fc, &fcoe_hostlist, list) {
lp = fc->lp;
if (lp->dev_stats[cpu] == NULL)
lp->dev_stats[cpu] =
kzalloc(sizeof(struct fcoe_dev_stats),
GFP_KERNEL);
}
write_unlock_bh(&fcoe_hostlist_lock);
}
/**
* fcoe_destroy_percpu_data() - destroys the associated cpu data
* @cpu: index for the cpu where fcoe cpu data will destroyed
*
* destroy percpu stats block called by cpu add/remove notifier
*
* Retuns: none
*/
static void fcoe_destroy_percpu_data(int cpu)
{
struct fc_lport *lp;
struct fcoe_softc *fc;
write_lock_bh(&fcoe_hostlist_lock);
list_for_each_entry(fc, &fcoe_hostlist, list) {
lp = fc->lp;
kfree(lp->dev_stats[cpu]);
lp->dev_stats[cpu] = NULL;
}
write_unlock_bh(&fcoe_hostlist_lock);
}
/**
* fcoe_cpu_callback() - fcoe cpu hotplug event callback
* @nfb: callback data block
* @action: event triggering the callback
* @hcpu: index for the cpu of this event
*
* this creates or destroys per cpu data for fcoe
*
* Returns NOTIFY_OK always.
*/
static int fcoe_cpu_callback(struct notifier_block *nfb, unsigned long action,
void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
switch (action) {
case CPU_ONLINE:
fcoe_create_percpu_data(cpu);
break;
case CPU_DEAD:
fcoe_destroy_percpu_data(cpu);
break;
default:
break;
}
return NOTIFY_OK;
}
#endif /* CONFIG_HOTPLUG_CPU */
/**
* fcoe_rcv() - this is the fcoe receive function called by NET_RX_SOFTIRQ
* @skb: the receive skb
* @dev: associated net device
* @ptype: context
* @odldev: last device
*
* this function will receive the packet and build fc frame and pass it up
*
* Returns: 0 for success
*/
int fcoe_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *ptype, struct net_device *olddev)
{
struct fc_lport *lp;
struct fcoe_rcv_info *fr;
struct fcoe_softc *fc;
struct fcoe_dev_stats *stats;
struct fc_frame_header *fh;
unsigned short oxid;
int cpu_idx;
struct fcoe_percpu_s *fps;
fc = container_of(ptype, struct fcoe_softc, fcoe_packet_type);
lp = fc->lp;
if (unlikely(lp == NULL)) {
FC_DBG("cannot find hba structure");
goto err2;
}
if (unlikely(debug_fcoe)) {
FC_DBG("skb_info: len:%d data_len:%d head:%p data:%p tail:%p "
"end:%p sum:%d dev:%s", skb->len, skb->data_len,
skb->head, skb->data, skb_tail_pointer(skb),
skb_end_pointer(skb), skb->csum,
skb->dev ? skb->dev->name : "<NULL>");
}
/* check for FCOE packet type */
if (unlikely(eth_hdr(skb)->h_proto != htons(ETH_P_FCOE))) {
FC_DBG("wrong FC type frame");
goto err;
}
/*
* Check for minimum frame length, and make sure required FCoE
* and FC headers are pulled into the linear data area.
*/
if (unlikely((skb->len < FCOE_MIN_FRAME) ||
!pskb_may_pull(skb, FCOE_HEADER_LEN)))
goto err;
skb_set_transport_header(skb, sizeof(struct fcoe_hdr));
fh = (struct fc_frame_header *) skb_transport_header(skb);
oxid = ntohs(fh->fh_ox_id);
fr = fcoe_dev_from_skb(skb);
fr->fr_dev = lp;
fr->ptype = ptype;
cpu_idx = 0;
#ifdef CONFIG_SMP
/*
* The incoming frame exchange id(oxid) is ANDed with num of online
* cpu bits to get cpu_idx and then this cpu_idx is used for selecting
* a per cpu kernel thread from fcoe_percpu. In case the cpu is
* offline or no kernel thread for derived cpu_idx then cpu_idx is
* initialize to first online cpu index.
*/
cpu_idx = oxid & (num_online_cpus() - 1);
if (!fcoe_percpu[cpu_idx] || !cpu_online(cpu_idx))
cpu_idx = first_cpu(cpu_online_map);
#endif
fps = fcoe_percpu[cpu_idx];
spin_lock_bh(&fps->fcoe_rx_list.lock);
__skb_queue_tail(&fps->fcoe_rx_list, skb);
if (fps->fcoe_rx_list.qlen == 1)
wake_up_process(fps->thread);
spin_unlock_bh(&fps->fcoe_rx_list.lock);
return 0;
err:
#ifdef CONFIG_SMP
stats = lp->dev_stats[smp_processor_id()];
#else
stats = lp->dev_stats[0];
#endif
if (stats)
stats->ErrorFrames++;
err2:
kfree_skb(skb);
return -1;
}
EXPORT_SYMBOL_GPL(fcoe_rcv);
/**
* fcoe_start_io() - pass to netdev to start xmit for fcoe
* @skb: the skb to be xmitted
*
* Returns: 0 for success
*/
static inline int fcoe_start_io(struct sk_buff *skb)
{
int rc;
skb_get(skb);
rc = dev_queue_xmit(skb);
if (rc != 0)
return rc;
kfree_skb(skb);
return 0;
}
/**
* fcoe_get_paged_crc_eof() - in case we need alloc a page for crc_eof
* @skb: the skb to be xmitted
* @tlen: total len
*
* Returns: 0 for success
*/
static int fcoe_get_paged_crc_eof(struct sk_buff *skb, int tlen)
{
struct fcoe_percpu_s *fps;
struct page *page;
int cpu_idx;
cpu_idx = get_cpu();
fps = fcoe_percpu[cpu_idx];
page = fps->crc_eof_page;
if (!page) {
page = alloc_page(GFP_ATOMIC);
if (!page) {
put_cpu();
return -ENOMEM;
}
fps->crc_eof_page = page;
WARN_ON(fps->crc_eof_offset != 0);
}
get_page(page);
skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, page,
fps->crc_eof_offset, tlen);
skb->len += tlen;
skb->data_len += tlen;
skb->truesize += tlen;
fps->crc_eof_offset += sizeof(struct fcoe_crc_eof);
if (fps->crc_eof_offset >= PAGE_SIZE) {
fps->crc_eof_page = NULL;
fps->crc_eof_offset = 0;
put_page(page);
}
put_cpu();
return 0;
}
/**
* fcoe_fc_crc() - calculates FC CRC in this fcoe skb
* @fp: the fc_frame containg data to be checksummed
*
* This uses crc32() to calculate the crc for fc frame
* Return : 32 bit crc
*/
u32 fcoe_fc_crc(struct fc_frame *fp)
{
struct sk_buff *skb = fp_skb(fp);
struct skb_frag_struct *frag;
unsigned char *data;
unsigned long off, len, clen;
u32 crc;
unsigned i;
crc = crc32(~0, skb->data, skb_headlen(skb));
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
frag = &skb_shinfo(skb)->frags[i];
off = frag->page_offset;
len = frag->size;
while (len > 0) {
clen = min(len, PAGE_SIZE - (off & ~PAGE_MASK));
data = kmap_atomic(frag->page + (off >> PAGE_SHIFT),
KM_SKB_DATA_SOFTIRQ);
crc = crc32(crc, data + (off & ~PAGE_MASK), clen);
kunmap_atomic(data, KM_SKB_DATA_SOFTIRQ);
off += clen;
len -= clen;
}
}
return crc;
}
EXPORT_SYMBOL_GPL(fcoe_fc_crc);
/**
* fcoe_xmit() - FCoE frame transmit function
* @lp: the associated local port
* @fp: the fc_frame to be transmitted
*
* Return : 0 for success
*/
int fcoe_xmit(struct fc_lport *lp, struct fc_frame *fp)
{
int wlen, rc = 0;
u32 crc;
struct ethhdr *eh;
struct fcoe_crc_eof *cp;
struct sk_buff *skb;
struct fcoe_dev_stats *stats;
struct fc_frame_header *fh;
unsigned int hlen; /* header length implies the version */
unsigned int tlen; /* trailer length */
unsigned int elen; /* eth header, may include vlan */
int flogi_in_progress = 0;
struct fcoe_softc *fc;
u8 sof, eof;
struct fcoe_hdr *hp;
WARN_ON((fr_len(fp) % sizeof(u32)) != 0);
fc = lport_priv(lp);
/*
* if it is a flogi then we need to learn gw-addr
* and my own fcid
*/
fh = fc_frame_header_get(fp);
if (unlikely(fh->fh_r_ctl == FC_RCTL_ELS_REQ)) {
if (fc_frame_payload_op(fp) == ELS_FLOGI) {
fc->flogi_oxid = ntohs(fh->fh_ox_id);
fc->address_mode = FCOE_FCOUI_ADDR_MODE;
fc->flogi_progress = 1;
flogi_in_progress = 1;
} else if (fc->flogi_progress && ntoh24(fh->fh_s_id) != 0) {
/*
* Here we must've gotten an SID by accepting an FLOGI
* from a point-to-point connection. Switch to using
* the source mac based on the SID. The destination
* MAC in this case would have been set by receving the
* FLOGI.
*/
fc_fcoe_set_mac(fc->data_src_addr, fh->fh_s_id);
fc->flogi_progress = 0;
}
}
skb = fp_skb(fp);
sof = fr_sof(fp);
eof = fr_eof(fp);
elen = (fc->real_dev->priv_flags & IFF_802_1Q_VLAN) ?
sizeof(struct vlan_ethhdr) : sizeof(struct ethhdr);
hlen = sizeof(struct fcoe_hdr);
tlen = sizeof(struct fcoe_crc_eof);
wlen = (skb->len - tlen + sizeof(crc)) / FCOE_WORD_TO_BYTE;
/* crc offload */
if (likely(lp->crc_offload)) {
skb->ip_summed = CHECKSUM_PARTIAL;
skb->csum_start = skb_headroom(skb);
skb->csum_offset = skb->len;
crc = 0;
} else {
skb->ip_summed = CHECKSUM_NONE;
crc = fcoe_fc_crc(fp);
}
/* copy fc crc and eof to the skb buff */
if (skb_is_nonlinear(skb)) {
skb_frag_t *frag;
if (fcoe_get_paged_crc_eof(skb, tlen)) {
kfree_skb(skb);
return -ENOMEM;
}
frag = &skb_shinfo(skb)->frags[skb_shinfo(skb)->nr_frags - 1];
cp = kmap_atomic(frag->page, KM_SKB_DATA_SOFTIRQ)
+ frag->page_offset;
} else {
cp = (struct fcoe_crc_eof *)skb_put(skb, tlen);
}
memset(cp, 0, sizeof(*cp));
cp->fcoe_eof = eof;
cp->fcoe_crc32 = cpu_to_le32(~crc);
if (skb_is_nonlinear(skb)) {
kunmap_atomic(cp, KM_SKB_DATA_SOFTIRQ);
cp = NULL;
}
/* adjust skb netowrk/transport offsets to match mac/fcoe/fc */
skb_push(skb, elen + hlen);
skb_reset_mac_header(skb);
skb_reset_network_header(skb);
skb->mac_len = elen;
skb->protocol = htons(ETH_P_FCOE);
skb->dev = fc->real_dev;
/* fill up mac and fcoe headers */
eh = eth_hdr(skb);
eh->h_proto = htons(ETH_P_FCOE);
if (fc->address_mode == FCOE_FCOUI_ADDR_MODE)
fc_fcoe_set_mac(eh->h_dest, fh->fh_d_id);
else
/* insert GW address */
memcpy(eh->h_dest, fc->dest_addr, ETH_ALEN);
if (unlikely(flogi_in_progress))
memcpy(eh->h_source, fc->ctl_src_addr, ETH_ALEN);
else
memcpy(eh->h_source, fc->data_src_addr, ETH_ALEN);
hp = (struct fcoe_hdr *)(eh + 1);
memset(hp, 0, sizeof(*hp));
if (FC_FCOE_VER)
FC_FCOE_ENCAPS_VER(hp, FC_FCOE_VER);
hp->fcoe_sof = sof;
#ifdef NETIF_F_FSO
/* fcoe lso, mss is in max_payload which is non-zero for FCP data */
if (lp->seq_offload && fr_max_payload(fp)) {
skb_shinfo(skb)->gso_type = SKB_GSO_FCOE;
skb_shinfo(skb)->gso_size = fr_max_payload(fp);
} else {
skb_shinfo(skb)->gso_type = 0;
skb_shinfo(skb)->gso_size = 0;
}
#endif
/* update tx stats: regardless if LLD fails */
stats = lp->dev_stats[smp_processor_id()];
if (stats) {
stats->TxFrames++;
stats->TxWords += wlen;
}
/* send down to lld */
fr_dev(fp) = lp;
if (fc->fcoe_pending_queue.qlen)
rc = fcoe_check_wait_queue(lp);
if (rc == 0)
rc = fcoe_start_io(skb);
if (rc) {
spin_lock_bh(&fc->fcoe_pending_queue.lock);
__skb_queue_tail(&fc->fcoe_pending_queue, skb);
spin_unlock_bh(&fc->fcoe_pending_queue.lock);
if (fc->fcoe_pending_queue.qlen > FCOE_MAX_QUEUE_DEPTH)
lp->qfull = 1;
}
return 0;
}
EXPORT_SYMBOL_GPL(fcoe_xmit);
/**
* fcoe_percpu_receive_thread() - recv thread per cpu
* @arg: ptr to the fcoe per cpu struct
*
* Return: 0 for success
*/
int fcoe_percpu_receive_thread(void *arg)
{
struct fcoe_percpu_s *p = arg;
u32 fr_len;
struct fc_lport *lp;
struct fcoe_rcv_info *fr;
struct fcoe_dev_stats *stats;
struct fc_frame_header *fh;
struct sk_buff *skb;
struct fcoe_crc_eof crc_eof;
struct fc_frame *fp;
u8 *mac = NULL;
struct fcoe_softc *fc;
struct fcoe_hdr *hp;
set_user_nice(current, -20);
while (!kthread_should_stop()) {
spin_lock_bh(&p->fcoe_rx_list.lock);
while ((skb = __skb_dequeue(&p->fcoe_rx_list)) == NULL) {
set_current_state(TASK_INTERRUPTIBLE);
spin_unlock_bh(&p->fcoe_rx_list.lock);
schedule();
set_current_state(TASK_RUNNING);
if (kthread_should_stop())
return 0;
spin_lock_bh(&p->fcoe_rx_list.lock);
}
spin_unlock_bh(&p->fcoe_rx_list.lock);
fr = fcoe_dev_from_skb(skb);
lp = fr->fr_dev;
if (unlikely(lp == NULL)) {
FC_DBG("invalid HBA Structure");
kfree_skb(skb);
continue;
}
stats = lp->dev_stats[smp_processor_id()];
if (unlikely(debug_fcoe)) {
FC_DBG("skb_info: len:%d data_len:%d head:%p data:%p "
"tail:%p end:%p sum:%d dev:%s",
skb->len, skb->data_len,
skb->head, skb->data, skb_tail_pointer(skb),
skb_end_pointer(skb), skb->csum,
skb->dev ? skb->dev->name : "<NULL>");
}
/*
* Save source MAC address before discarding header.
*/
fc = lport_priv(lp);
if (unlikely(fc->flogi_progress))
mac = eth_hdr(skb)->h_source;
if (skb_is_nonlinear(skb))
skb_linearize(skb); /* not ideal */
/*
* Frame length checks and setting up the header pointers
* was done in fcoe_rcv already.
*/
hp = (struct fcoe_hdr *) skb_network_header(skb);
fh = (struct fc_frame_header *) skb_transport_header(skb);
if (unlikely(FC_FCOE_DECAPS_VER(hp) != FC_FCOE_VER)) {
if (stats) {
if (stats->ErrorFrames < 5)
FC_DBG("unknown FCoE version %x",
FC_FCOE_DECAPS_VER(hp));
stats->ErrorFrames++;
}
kfree_skb(skb);
continue;
}
skb_pull(skb, sizeof(struct fcoe_hdr));
fr_len = skb->len - sizeof(struct fcoe_crc_eof);
if (stats) {
stats->RxFrames++;
stats->RxWords += fr_len / FCOE_WORD_TO_BYTE;
}
fp = (struct fc_frame *)skb;
fc_frame_init(fp);
fr_dev(fp) = lp;
fr_sof(fp) = hp->fcoe_sof;
/* Copy out the CRC and EOF trailer for access */
if (skb_copy_bits(skb, fr_len, &crc_eof, sizeof(crc_eof))) {
kfree_skb(skb);
continue;
}
fr_eof(fp) = crc_eof.fcoe_eof;
fr_crc(fp) = crc_eof.fcoe_crc32;
if (pskb_trim(skb, fr_len)) {
kfree_skb(skb);
continue;
}
/*
* We only check CRC if no offload is available and if it is
* it's solicited data, in which case, the FCP layer would
* check it during the copy.
*/
if (lp->crc_offload && skb->ip_summed == CHECKSUM_UNNECESSARY)
fr_flags(fp) &= ~FCPHF_CRC_UNCHECKED;
else
fr_flags(fp) |= FCPHF_CRC_UNCHECKED;
fh = fc_frame_header_get(fp);
if (fh->fh_r_ctl == FC_RCTL_DD_SOL_DATA &&
fh->fh_type == FC_TYPE_FCP) {
fc_exch_recv(lp, lp->emp, fp);
continue;
}
if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) {
if (le32_to_cpu(fr_crc(fp)) !=
~crc32(~0, skb->data, fr_len)) {
if (debug_fcoe || stats->InvalidCRCCount < 5)
printk(KERN_WARNING "fcoe: dropping "
"frame with CRC error\n");
stats->InvalidCRCCount++;
stats->ErrorFrames++;
fc_frame_free(fp);
continue;
}
fr_flags(fp) &= ~FCPHF_CRC_UNCHECKED;
}
/* non flogi and non data exchanges are handled here */
if (unlikely(fc->flogi_progress))
fcoe_recv_flogi(fc, fp, mac);
fc_exch_recv(lp, lp->emp, fp);
}
return 0;
}
/**
* fcoe_recv_flogi() - flogi receive function
* @fc: associated fcoe_softc
* @fp: the recieved frame
* @sa: the source address of this flogi
*
* This is responsible to parse the flogi response and sets the corresponding
* mac address for the initiator, eitehr OUI based or GW based.
*
* Returns: none
*/
static void fcoe_recv_flogi(struct fcoe_softc *fc, struct fc_frame *fp, u8 *sa)
{
struct fc_frame_header *fh;
u8 op;
fh = fc_frame_header_get(fp);
if (fh->fh_type != FC_TYPE_ELS)
return;
op = fc_frame_payload_op(fp);
if (op == ELS_LS_ACC && fh->fh_r_ctl == FC_RCTL_ELS_REP &&
fc->flogi_oxid == ntohs(fh->fh_ox_id)) {
/*
* FLOGI accepted.
* If the src mac addr is FC_OUI-based, then we mark the
* address_mode flag to use FC_OUI-based Ethernet DA.
* Otherwise we use the FCoE gateway addr
*/
if (!compare_ether_addr(sa, (u8[6]) FC_FCOE_FLOGI_MAC)) {
fc->address_mode = FCOE_FCOUI_ADDR_MODE;
} else {
memcpy(fc->dest_addr, sa, ETH_ALEN);
fc->address_mode = FCOE_GW_ADDR_MODE;
}
/*
* Remove any previously-set unicast MAC filter.
* Add secondary FCoE MAC address filter for our OUI.
*/
rtnl_lock();
if (compare_ether_addr(fc->data_src_addr, (u8[6]) { 0 }))
dev_unicast_delete(fc->real_dev, fc->data_src_addr,
ETH_ALEN);
fc_fcoe_set_mac(fc->data_src_addr, fh->fh_d_id);
dev_unicast_add(fc->real_dev, fc->data_src_addr, ETH_ALEN);
rtnl_unlock();
fc->flogi_progress = 0;
} else if (op == ELS_FLOGI && fh->fh_r_ctl == FC_RCTL_ELS_REQ && sa) {
/*
* Save source MAC for point-to-point responses.
*/
memcpy(fc->dest_addr, sa, ETH_ALEN);
fc->address_mode = FCOE_GW_ADDR_MODE;
}
}
/**
* fcoe_watchdog() - fcoe timer callback
* @vp:
*
* This checks the pending queue length for fcoe and set lport qfull
* if the FCOE_MAX_QUEUE_DEPTH is reached. This is done for all fc_lport on the
* fcoe_hostlist.
*
* Returns: 0 for success
*/
void fcoe_watchdog(ulong vp)
{
struct fcoe_softc *fc;
read_lock(&fcoe_hostlist_lock);
list_for_each_entry(fc, &fcoe_hostlist, list) {
if (fc->lp)
fcoe_check_wait_queue(fc->lp);
}
read_unlock(&fcoe_hostlist_lock);
fcoe_timer.expires = jiffies + (1 * HZ);
add_timer(&fcoe_timer);
}
/**
* fcoe_check_wait_queue() - put the skb into fcoe pending xmit queue
* @lp: the fc_port for this skb
* @skb: the associated skb to be xmitted
*
* This empties the wait_queue, dequeue the head of the wait_queue queue
* and calls fcoe_start_io() for each packet, if all skb have been
* transmitted, return qlen or -1 if a error occurs, then restore
* wait_queue and try again later.
*
* The wait_queue is used when the skb transmit fails. skb will go
* in the wait_queue which will be emptied by the time function OR
* by the next skb transmit.
*
* Returns: 0 for success
*/
static int fcoe_check_wait_queue(struct fc_lport *lp)
{
struct fcoe_softc *fc = lport_priv(lp);
struct sk_buff *skb;
int rc = -1;
spin_lock_bh(&fc->fcoe_pending_queue.lock);
if (fc->fcoe_pending_queue_active)
goto out;
fc->fcoe_pending_queue_active = 1;
while (fc->fcoe_pending_queue.qlen) {
/* keep qlen > 0 until fcoe_start_io succeeds */
fc->fcoe_pending_queue.qlen++;
skb = __skb_dequeue(&fc->fcoe_pending_queue);
spin_unlock_bh(&fc->fcoe_pending_queue.lock);
rc = fcoe_start_io(skb);
spin_lock_bh(&fc->fcoe_pending_queue.lock);
if (rc) {
__skb_queue_head(&fc->fcoe_pending_queue, skb);
/* undo temporary increment above */
fc->fcoe_pending_queue.qlen--;
break;
}
/* undo temporary increment above */
fc->fcoe_pending_queue.qlen--;
}
if (fc->fcoe_pending_queue.qlen < FCOE_LOW_QUEUE_DEPTH)
lp->qfull = 0;
fc->fcoe_pending_queue_active = 0;
rc = fc->fcoe_pending_queue.qlen;
out:
spin_unlock_bh(&fc->fcoe_pending_queue.lock);
return rc;
}
/**
* fcoe_dev_setup() - setup link change notification interface
*/
static void fcoe_dev_setup()
{
/*
* here setup a interface specific wd time to
* monitor the link state
*/
register_netdevice_notifier(&fcoe_notifier);
}
/**
* fcoe_dev_setup() - cleanup link change notification interface
*/
static void fcoe_dev_cleanup(void)
{
unregister_netdevice_notifier(&fcoe_notifier);
}
/**
* fcoe_device_notification() - netdev event notification callback
* @notifier: context of the notification
* @event: type of event
* @ptr: fixed array for output parsed ifname
*
* This function is called by the ethernet driver in case of link change event
*
* Returns: 0 for success
*/
static int fcoe_device_notification(struct notifier_block *notifier,
ulong event, void *ptr)
{
struct fc_lport *lp = NULL;
struct net_device *real_dev = ptr;
struct fcoe_softc *fc;
struct fcoe_dev_stats *stats;
u32 new_link_up;
u32 mfs;
int rc = NOTIFY_OK;
read_lock(&fcoe_hostlist_lock);
list_for_each_entry(fc, &fcoe_hostlist, list) {
if (fc->real_dev == real_dev) {
lp = fc->lp;
break;
}
}
read_unlock(&fcoe_hostlist_lock);
if (lp == NULL) {
rc = NOTIFY_DONE;
goto out;
}
new_link_up = lp->link_up;
switch (event) {
case NETDEV_DOWN:
case NETDEV_GOING_DOWN:
new_link_up = 0;
break;
case NETDEV_UP:
case NETDEV_CHANGE:
new_link_up = !fcoe_link_ok(lp);
break;
case NETDEV_CHANGEMTU:
mfs = fc->real_dev->mtu -
(sizeof(struct fcoe_hdr) +
sizeof(struct fcoe_crc_eof));
if (mfs >= FC_MIN_MAX_FRAME)
fc_set_mfs(lp, mfs);
new_link_up = !fcoe_link_ok(lp);
break;
case NETDEV_REGISTER:
break;
default:
FC_DBG("unknown event %ld call", event);
}
if (lp->link_up != new_link_up) {
if (new_link_up)
fc_linkup(lp);
else {
stats = lp->dev_stats[smp_processor_id()];
if (stats)
stats->LinkFailureCount++;
fc_linkdown(lp);
fcoe_clean_pending_queue(lp);
}
}
out:
return rc;
}
/**
* fcoe_if_to_netdev() - parse a name buffer to get netdev
* @ifname: fixed array for output parsed ifname
* @buffer: incoming buffer to be copied
*
* Returns: NULL or ptr to netdeive
*/
static struct net_device *fcoe_if_to_netdev(const char *buffer)
{
char *cp;
char ifname[IFNAMSIZ + 2];
if (buffer) {
strlcpy(ifname, buffer, IFNAMSIZ);
cp = ifname + strlen(ifname);
while (--cp >= ifname && *cp == '\n')
*cp = '\0';
return dev_get_by_name(&init_net, ifname);
}
return NULL;
}
/**
* fcoe_netdev_to_module_owner() - finds out the nic drive moddule of the netdev
* @netdev: the target netdev
*
* Returns: ptr to the struct module, NULL for failure
*/
static struct module *
fcoe_netdev_to_module_owner(const struct net_device *netdev)
{
struct device *dev;
if (!netdev)
return NULL;
dev = netdev->dev.parent;
if (!dev)
return NULL;
if (!dev->driver)
return NULL;
return dev->driver->owner;
}
/**
* fcoe_ethdrv_get() - Hold the Ethernet driver
* @netdev: the target netdev
*
* Holds the Ethernet driver module by try_module_get() for
* the corresponding netdev.
*
* Returns: 0 for succsss
*/
static int fcoe_ethdrv_get(const struct net_device *netdev)
{
struct module *owner;
owner = fcoe_netdev_to_module_owner(netdev);
if (owner) {
printk(KERN_DEBUG "fcoe:hold driver module %s for %s\n",
module_name(owner), netdev->name);
return try_module_get(owner);
}
return -ENODEV;
}
/**
* fcoe_ethdrv_put() - Release the Ethernet driver
* @netdev: the target netdev
*
* Releases the Ethernet driver module by module_put for
* the corresponding netdev.
*
* Returns: 0 for succsss
*/
static int fcoe_ethdrv_put(const struct net_device *netdev)
{
struct module *owner;
owner = fcoe_netdev_to_module_owner(netdev);
if (owner) {
printk(KERN_DEBUG "fcoe:release driver module %s for %s\n",
module_name(owner), netdev->name);
module_put(owner);
return 0;
}
return -ENODEV;
}
/**
* fcoe_destroy() - handles the destroy from sysfs
* @buffer: expcted to be a eth if name
* @kp: associated kernel param
*
* Returns: 0 for success
*/
static int fcoe_destroy(const char *buffer, struct kernel_param *kp)
{
int rc;
struct net_device *netdev;
netdev = fcoe_if_to_netdev(buffer);
if (!netdev) {
rc = -ENODEV;
goto out_nodev;
}
/* look for existing lport */
if (!fcoe_hostlist_lookup(netdev)) {
rc = -ENODEV;
goto out_putdev;
}
/* pass to transport */
rc = fcoe_transport_release(netdev);
if (rc) {
printk(KERN_ERR "fcoe: fcoe_transport_release(%s) failed\n",
netdev->name);
rc = -EIO;
goto out_putdev;
}
fcoe_ethdrv_put(netdev);
rc = 0;
out_putdev:
dev_put(netdev);
out_nodev:
return rc;
}
/**
* fcoe_create() - Handles the create call from sysfs
* @buffer: expcted to be a eth if name
* @kp: associated kernel param
*
* Returns: 0 for success
*/
static int fcoe_create(const char *buffer, struct kernel_param *kp)
{
int rc;
struct net_device *netdev;
netdev = fcoe_if_to_netdev(buffer);
if (!netdev) {
rc = -ENODEV;
goto out_nodev;
}
/* look for existing lport */
if (fcoe_hostlist_lookup(netdev)) {
rc = -EEXIST;
goto out_putdev;
}
fcoe_ethdrv_get(netdev);
/* pass to transport */
rc = fcoe_transport_attach(netdev);
if (rc) {
printk(KERN_ERR "fcoe: fcoe_transport_attach(%s) failed\n",
netdev->name);
fcoe_ethdrv_put(netdev);
rc = -EIO;
goto out_putdev;
}
rc = 0;
out_putdev:
dev_put(netdev);
out_nodev:
return rc;
}
module_param_call(create, fcoe_create, NULL, NULL, S_IWUSR);
__MODULE_PARM_TYPE(create, "string");
MODULE_PARM_DESC(create, "Create fcoe port using net device passed in.");
module_param_call(destroy, fcoe_destroy, NULL, NULL, S_IWUSR);
__MODULE_PARM_TYPE(destroy, "string");
MODULE_PARM_DESC(destroy, "Destroy fcoe port");
/**
* fcoe_link_ok() - Check if link is ok for the fc_lport
* @lp: ptr to the fc_lport
*
* Any permanently-disqualifying conditions have been previously checked.
* This also updates the speed setting, which may change with link for 100/1000.
*
* This function should probably be checking for PAUSE support at some point
* in the future. Currently Per-priority-pause is not determinable using
* ethtool, so we shouldn't be restrictive until that problem is resolved.
*
* Returns: 0 if link is OK for use by FCoE.
*
*/
int fcoe_link_ok(struct fc_lport *lp)
{
struct fcoe_softc *fc = lport_priv(lp);
struct net_device *dev = fc->real_dev;
struct ethtool_cmd ecmd = { ETHTOOL_GSET };
int rc = 0;
if ((dev->flags & IFF_UP) && netif_carrier_ok(dev)) {
dev = fc->phys_dev;
if (dev->ethtool_ops->get_settings) {
dev->ethtool_ops->get_settings(dev, &ecmd);
lp->link_supported_speeds &=
~(FC_PORTSPEED_1GBIT | FC_PORTSPEED_10GBIT);
if (ecmd.supported & (SUPPORTED_1000baseT_Half |
SUPPORTED_1000baseT_Full))
lp->link_supported_speeds |= FC_PORTSPEED_1GBIT;
if (ecmd.supported & SUPPORTED_10000baseT_Full)
lp->link_supported_speeds |=
FC_PORTSPEED_10GBIT;
if (ecmd.speed == SPEED_1000)
lp->link_speed = FC_PORTSPEED_1GBIT;
if (ecmd.speed == SPEED_10000)
lp->link_speed = FC_PORTSPEED_10GBIT;
}
} else
rc = -1;
return rc;
}
EXPORT_SYMBOL_GPL(fcoe_link_ok);
/**
* fcoe_percpu_clean() - Clear the pending skbs for an lport
* @lp: the fc_lport
*/
void fcoe_percpu_clean(struct fc_lport *lp)
{
int idx;
struct fcoe_percpu_s *pp;
struct fcoe_rcv_info *fr;
struct sk_buff_head *list;
struct sk_buff *skb, *next;
struct sk_buff *head;
for (idx = 0; idx < NR_CPUS; idx++) {
if (fcoe_percpu[idx]) {
pp = fcoe_percpu[idx];
spin_lock_bh(&pp->fcoe_rx_list.lock);
list = &pp->fcoe_rx_list;
head = list->next;
for (skb = head; skb != (struct sk_buff *)list;
skb = next) {
next = skb->next;
fr = fcoe_dev_from_skb(skb);
if (fr->fr_dev == lp) {
__skb_unlink(skb, list);
kfree_skb(skb);
}
}
spin_unlock_bh(&pp->fcoe_rx_list.lock);
}
}
}
EXPORT_SYMBOL_GPL(fcoe_percpu_clean);
/**
* fcoe_clean_pending_queue() - Dequeue a skb and free it
* @lp: the corresponding fc_lport
*
* Returns: none
*/
void fcoe_clean_pending_queue(struct fc_lport *lp)
{
struct fcoe_softc *fc = lport_priv(lp);
struct sk_buff *skb;
spin_lock_bh(&fc->fcoe_pending_queue.lock);
while ((skb = __skb_dequeue(&fc->fcoe_pending_queue)) != NULL) {
spin_unlock_bh(&fc->fcoe_pending_queue.lock);
kfree_skb(skb);
spin_lock_bh(&fc->fcoe_pending_queue.lock);
}
spin_unlock_bh(&fc->fcoe_pending_queue.lock);
}
EXPORT_SYMBOL_GPL(fcoe_clean_pending_queue);
/**
* libfc_host_alloc() - Allocate a Scsi_Host with room for the fc_lport
* @sht: ptr to the scsi host templ
* @priv_size: size of private data after fc_lport
*
* Returns: ptr to Scsi_Host
* TODO: to libfc?
*/
static inline struct Scsi_Host *
libfc_host_alloc(struct scsi_host_template *sht, int priv_size)
{
return scsi_host_alloc(sht, sizeof(struct fc_lport) + priv_size);
}
/**
* fcoe_host_alloc() - Allocate a Scsi_Host with room for the fcoe_softc
* @sht: ptr to the scsi host templ
* @priv_size: size of private data after fc_lport
*
* Returns: ptr to Scsi_Host
*/
struct Scsi_Host *fcoe_host_alloc(struct scsi_host_template *sht, int priv_size)
{
return libfc_host_alloc(sht, sizeof(struct fcoe_softc) + priv_size);
}
EXPORT_SYMBOL_GPL(fcoe_host_alloc);
/**
* fcoe_reset() - Resets the fcoe
* @shost: shost the reset is from
*
* Returns: always 0
*/
int fcoe_reset(struct Scsi_Host *shost)
{
struct fc_lport *lport = shost_priv(shost);
fc_lport_reset(lport);
return 0;
}
EXPORT_SYMBOL_GPL(fcoe_reset);
/**
* fcoe_wwn_from_mac() - Converts 48-bit IEEE MAC address to 64-bit FC WWN.
* @mac: mac address
* @scheme: check port
* @port: port indicator for converting
*
* Returns: u64 fc world wide name
*/
u64 fcoe_wwn_from_mac(unsigned char mac[MAX_ADDR_LEN],
unsigned int scheme, unsigned int port)
{
u64 wwn;
u64 host_mac;
/* The MAC is in NO, so flip only the low 48 bits */
host_mac = ((u64) mac[0] << 40) |
((u64) mac[1] << 32) |
((u64) mac[2] << 24) |
((u64) mac[3] << 16) |
((u64) mac[4] << 8) |
(u64) mac[5];
WARN_ON(host_mac >= (1ULL << 48));
wwn = host_mac | ((u64) scheme << 60);
switch (scheme) {
case 1:
WARN_ON(port != 0);
break;
case 2:
WARN_ON(port >= 0xfff);
wwn |= (u64) port << 48;
break;
default:
WARN_ON(1);
break;
}
return wwn;
}
EXPORT_SYMBOL_GPL(fcoe_wwn_from_mac);
/**
* fcoe_hostlist_lookup_softc() - find the corresponding lport by a given device
* @device: this is currently ptr to net_device
*
* Returns: NULL or the located fcoe_softc
*/
static struct fcoe_softc *
fcoe_hostlist_lookup_softc(const struct net_device *dev)
{
struct fcoe_softc *fc;
read_lock(&fcoe_hostlist_lock);
list_for_each_entry(fc, &fcoe_hostlist, list) {
if (fc->real_dev == dev) {
read_unlock(&fcoe_hostlist_lock);
return fc;
}
}
read_unlock(&fcoe_hostlist_lock);
return NULL;
}
/**
* fcoe_hostlist_lookup() - Find the corresponding lport by netdev
* @netdev: ptr to net_device
*
* Returns: 0 for success
*/
struct fc_lport *fcoe_hostlist_lookup(const struct net_device *netdev)
{
struct fcoe_softc *fc;
fc = fcoe_hostlist_lookup_softc(netdev);
return (fc) ? fc->lp : NULL;
}
EXPORT_SYMBOL_GPL(fcoe_hostlist_lookup);
/**
* fcoe_hostlist_add() - Add a lport to lports list
* @lp: ptr to the fc_lport to badded
*
* Returns: 0 for success
*/
int fcoe_hostlist_add(const struct fc_lport *lp)
{
struct fcoe_softc *fc;
fc = fcoe_hostlist_lookup_softc(fcoe_netdev(lp));
if (!fc) {
fc = lport_priv(lp);
write_lock_bh(&fcoe_hostlist_lock);
list_add_tail(&fc->list, &fcoe_hostlist);
write_unlock_bh(&fcoe_hostlist_lock);
}
return 0;
}
EXPORT_SYMBOL_GPL(fcoe_hostlist_add);
/**
* fcoe_hostlist_remove() - remove a lport from lports list
* @lp: ptr to the fc_lport to badded
*
* Returns: 0 for success
*/
int fcoe_hostlist_remove(const struct fc_lport *lp)
{
struct fcoe_softc *fc;
fc = fcoe_hostlist_lookup_softc(fcoe_netdev(lp));
BUG_ON(!fc);
write_lock_bh(&fcoe_hostlist_lock);
list_del(&fc->list);
write_unlock_bh(&fcoe_hostlist_lock);
return 0;
}
EXPORT_SYMBOL_GPL(fcoe_hostlist_remove);
/**
* fcoe_libfc_config() - sets up libfc related properties for lport
* @lp: ptr to the fc_lport
* @tt: libfc function template
*
* Returns : 0 for success
*/
int fcoe_libfc_config(struct fc_lport *lp, struct libfc_function_template *tt)
{
/* Set the function pointers set by the LLDD */
memcpy(&lp->tt, tt, sizeof(*tt));
if (fc_fcp_init(lp))
return -ENOMEM;
fc_exch_init(lp);
fc_elsct_init(lp);
fc_lport_init(lp);
fc_rport_init(lp);
fc_disc_init(lp);
return 0;
}
EXPORT_SYMBOL_GPL(fcoe_libfc_config);
/**
* fcoe_init() - fcoe module loading initialization
*
* Initialization routine
* 1. Will create fc transport software structure
* 2. initialize the link list of port information structure
*
* Returns 0 on success, negative on failure
*/
static int __init fcoe_init(void)
{
int cpu;
struct fcoe_percpu_s *p;
INIT_LIST_HEAD(&fcoe_hostlist);
rwlock_init(&fcoe_hostlist_lock);
#ifdef CONFIG_HOTPLUG_CPU
register_cpu_notifier(&fcoe_cpu_notifier);
#endif /* CONFIG_HOTPLUG_CPU */
/*
* initialize per CPU interrupt thread
*/
for_each_online_cpu(cpu) {
p = kzalloc(sizeof(struct fcoe_percpu_s), GFP_KERNEL);
if (p) {
p->thread = kthread_create(fcoe_percpu_receive_thread,
(void *)p,
"fcoethread/%d", cpu);
/*
* if there is no error then bind the thread to the cpu
* initialize the semaphore and skb queue head
*/
if (likely(!IS_ERR(p->thread))) {
p->cpu = cpu;
fcoe_percpu[cpu] = p;
skb_queue_head_init(&p->fcoe_rx_list);
kthread_bind(p->thread, cpu);
wake_up_process(p->thread);
} else {
fcoe_percpu[cpu] = NULL;
kfree(p);
}
}
}
/*
* setup link change notification
*/
fcoe_dev_setup();
setup_timer(&fcoe_timer, fcoe_watchdog, 0);
mod_timer(&fcoe_timer, jiffies + (10 * HZ));
/* initiatlize the fcoe transport */
fcoe_transport_init();
fcoe_sw_init();
return 0;
}
module_init(fcoe_init);
/**
* fcoe_exit() - fcoe module unloading cleanup
*
* Returns 0 on success, negative on failure
*/
static void __exit fcoe_exit(void)
{
u32 idx;
struct fcoe_softc *fc, *tmp;
struct fcoe_percpu_s *p;
struct sk_buff *skb;
/*
* Stop all call back interfaces
*/
#ifdef CONFIG_HOTPLUG_CPU
unregister_cpu_notifier(&fcoe_cpu_notifier);
#endif /* CONFIG_HOTPLUG_CPU */
fcoe_dev_cleanup();
/*
* stop timer
*/
del_timer_sync(&fcoe_timer);
/* releases the associated fcoe transport for each lport */
list_for_each_entry_safe(fc, tmp, &fcoe_hostlist, list)
fcoe_transport_release(fc->real_dev);
for (idx = 0; idx < NR_CPUS; idx++) {
if (fcoe_percpu[idx]) {
kthread_stop(fcoe_percpu[idx]->thread);
p = fcoe_percpu[idx];
spin_lock_bh(&p->fcoe_rx_list.lock);
while ((skb = __skb_dequeue(&p->fcoe_rx_list)) != NULL)
kfree_skb(skb);
spin_unlock_bh(&p->fcoe_rx_list.lock);
if (fcoe_percpu[idx]->crc_eof_page)
put_page(fcoe_percpu[idx]->crc_eof_page);
kfree(fcoe_percpu[idx]);
}
}
/* remove sw trasnport */
fcoe_sw_exit();
/* detach the transport */
fcoe_transport_exit();
}
module_exit(fcoe_exit);