/*
* Copyright (c) 2012 Intel Corporation. All rights reserved.
* Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved.
* Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
/*
* This file contains support for diagnostic functions. It is accessed by
* opening the qib_diag device, normally minor number 129. Diagnostic use
* of the QLogic_IB chip may render the chip or board unusable until the
* driver is unloaded, or in some cases, until the system is rebooted.
*
* Accesses to the chip through this interface are not similar to going
* through the /sys/bus/pci resource mmap interface.
*/
#include <linux/io.h>
#include <linux/pci.h>
#include <linux/poll.h>
#include <linux/vmalloc.h>
#include <linux/export.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include "qib.h"
#include "qib_common.h"
#undef pr_fmt
#define pr_fmt(fmt) QIB_DRV_NAME ": " fmt
/*
* Each client that opens the diag device must read then write
* offset 0, to prevent lossage from random cat or od. diag_state
* sequences this "handshake".
*/
enum diag_state { UNUSED = 0, OPENED, INIT, READY };
/* State for an individual client. PID so children cannot abuse handshake */
static struct qib_diag_client {
struct qib_diag_client *next;
struct qib_devdata *dd;
pid_t pid;
enum diag_state state;
} *client_pool;
/*
* Get a client struct. Recycled if possible, else kmalloc.
* Must be called with qib_mutex held
*/
static struct qib_diag_client *get_client(struct qib_devdata *dd)
{
struct qib_diag_client *dc;
dc = client_pool;
if (dc)
/* got from pool remove it and use */
client_pool = dc->next;
else
/* None in pool, alloc and init */
dc = kmalloc(sizeof(*dc), GFP_KERNEL);
if (dc) {
dc->next = NULL;
dc->dd = dd;
dc->pid = current->pid;
dc->state = OPENED;
}
return dc;
}
/*
* Return to pool. Must be called with qib_mutex held
*/
static void return_client(struct qib_diag_client *dc)
{
struct qib_devdata *dd = dc->dd;
struct qib_diag_client *tdc, *rdc;
rdc = NULL;
if (dc == dd->diag_client) {
dd->diag_client = dc->next;
rdc = dc;
} else {
tdc = dc->dd->diag_client;
while (tdc) {
if (dc == tdc->next) {
tdc->next = dc->next;
rdc = dc;
break;
}
tdc = tdc->next;
}
}
if (rdc) {
rdc->state = UNUSED;
rdc->dd = NULL;
rdc->pid = 0;
rdc->next = client_pool;
client_pool = rdc;
}
}
static int qib_diag_open(struct inode *in, struct file *fp);
static int qib_diag_release(struct inode *in, struct file *fp);
static ssize_t qib_diag_read(struct file *fp, char __user *data,
size_t count, loff_t *off);
static ssize_t qib_diag_write(struct file *fp, const char __user *data,
size_t count, loff_t *off);
static const struct file_operations diag_file_ops = {
.owner = THIS_MODULE,
.write = qib_diag_write,
.read = qib_diag_read,
.open = qib_diag_open,
.release = qib_diag_release,
.llseek = default_llseek,
};
static atomic_t diagpkt_count = ATOMIC_INIT(0);
static struct cdev *diagpkt_cdev;
static struct device *diagpkt_device;
static ssize_t qib_diagpkt_write(struct file *fp, const char __user *data,
size_t count, loff_t *off);
static const struct file_operations diagpkt_file_ops = {
.owner = THIS_MODULE,
.write = qib_diagpkt_write,
.llseek = noop_llseek,
};
int qib_diag_add(struct qib_devdata *dd)
{
char name[16];
int ret = 0;
if (atomic_inc_return(&diagpkt_count) == 1) {
ret = qib_cdev_init(QIB_DIAGPKT_MINOR, "ipath_diagpkt",
&diagpkt_file_ops, &diagpkt_cdev,
&diagpkt_device);
if (ret)
goto done;
}
snprintf(name, sizeof(name), "ipath_diag%d", dd->unit);
ret = qib_cdev_init(QIB_DIAG_MINOR_BASE + dd->unit, name,
&diag_file_ops, &dd->diag_cdev,
&dd->diag_device);
done:
return ret;
}
static void qib_unregister_observers(struct qib_devdata *dd);
void qib_diag_remove(struct qib_devdata *dd)
{
struct qib_diag_client *dc;
if (atomic_dec_and_test(&diagpkt_count))
qib_cdev_cleanup(&diagpkt_cdev, &diagpkt_device);
qib_cdev_cleanup(&dd->diag_cdev, &dd->diag_device);
/*
* Return all diag_clients of this device. There should be none,
* as we are "guaranteed" that no clients are still open
*/
while (dd->diag_client)
return_client(dd->diag_client);
/* Now clean up all unused client structs */
while (client_pool) {
dc = client_pool;
client_pool = dc->next;
kfree(dc);
}
/* Clean up observer list */
qib_unregister_observers(dd);
}
/* qib_remap_ioaddr32 - remap an offset into chip address space to __iomem *
*
* @dd: the qlogic_ib device
* @offs: the offset in chip-space
* @cntp: Pointer to max (byte) count for transfer starting at offset
* This returns a u32 __iomem * so it can be used for both 64 and 32-bit
* mapping. It is needed because with the use of PAT for control of
* write-combining, the logically contiguous address-space of the chip
* may be split into virtually non-contiguous spaces, with different
* attributes, which are them mapped to contiguous physical space
* based from the first BAR.
*
* The code below makes the same assumptions as were made in
* init_chip_wc_pat() (qib_init.c), copied here:
* Assumes chip address space looks like:
* - kregs + sregs + cregs + uregs (in any order)
* - piobufs (2K and 4K bufs in either order)
* or:
* - kregs + sregs + cregs (in any order)
* - piobufs (2K and 4K bufs in either order)
* - uregs
*
* If cntp is non-NULL, returns how many bytes from offset can be accessed
* Returns 0 if the offset is not mapped.
*/
static u32 __iomem *qib_remap_ioaddr32(struct qib_devdata *dd, u32 offset,
u32 *cntp)
{
u32 kreglen;
u32 snd_bottom, snd_lim = 0;
u32 __iomem *krb32 = (u32 __iomem *)dd->kregbase;
u32 __iomem *map = NULL;
u32 cnt = 0;
u32 tot4k, offs4k;
/* First, simplest case, offset is within the first map. */
kreglen = (dd->kregend - dd->kregbase) * sizeof(u64);
if (offset < kreglen) {
map = krb32 + (offset / sizeof(u32));
cnt = kreglen - offset;
goto mapped;
}
/*
* Next check for user regs, the next most common case,
* and a cheap check because if they are not in the first map
* they are last in chip.
*/
if (dd->userbase) {
/* If user regs mapped, they are after send, so set limit. */
u32 ulim = (dd->cfgctxts * dd->ureg_align) + dd->uregbase;
if (!dd->piovl15base)
snd_lim = dd->uregbase;
krb32 = (u32 __iomem *)dd->userbase;
if (offset >= dd->uregbase && offset < ulim) {
map = krb32 + (offset - dd->uregbase) / sizeof(u32);
cnt = ulim - offset;
goto mapped;
}
}
/*
* Lastly, check for offset within Send Buffers.
* This is gnarly because struct devdata is deliberately vague
* about things like 7322 VL15 buffers, and we are not in
* chip-specific code here, so should not make many assumptions.
* The one we _do_ make is that the only chip that has more sndbufs
* than we admit is the 7322, and it has userregs above that, so
* we know the snd_lim.
*/
/* Assume 2K buffers are first. */
snd_bottom = dd->pio2k_bufbase;
if (snd_lim == 0) {
u32 tot2k = dd->piobcnt2k * ALIGN(dd->piosize2k, dd->palign);
snd_lim = snd_bottom + tot2k;
}
/* If 4k buffers exist, account for them by bumping
* appropriate limit.
*/
tot4k = dd->piobcnt4k * dd->align4k;
offs4k = dd->piobufbase >> 32;
if (dd->piobcnt4k) {
if (snd_bottom > offs4k)
snd_bottom = offs4k;
else {
/* 4k above 2k. Bump snd_lim, if needed*/
if (!dd->userbase || dd->piovl15base)
snd_lim = offs4k + tot4k;
}
}
/*
* Judgement call: can we ignore the space between SendBuffs and
* UserRegs, where we would like to see vl15 buffs, but not more?
*/
if (offset >= snd_bottom && offset < snd_lim) {
offset -= snd_bottom;
map = (u32 __iomem *)dd->piobase + (offset / sizeof(u32));
cnt = snd_lim - offset;
}
if (!map && offs4k && dd->piovl15base) {
snd_lim = offs4k + tot4k + 2 * dd->align4k;
if (offset >= (offs4k + tot4k) && offset < snd_lim) {
map = (u32 __iomem *)dd->piovl15base +
((offset - (offs4k + tot4k)) / sizeof(u32));
cnt = snd_lim - offset;
}
}
mapped:
if (cntp)
*cntp = cnt;
return map;
}
/*
* qib_read_umem64 - read a 64-bit quantity from the chip into user space
* @dd: the qlogic_ib device
* @uaddr: the location to store the data in user memory
* @regoffs: the offset from BAR0 (_NOT_ full pointer, anymore)
* @count: number of bytes to copy (multiple of 32 bits)
*
* This function also localizes all chip memory accesses.
* The copy should be written such that we read full cacheline packets
* from the chip. This is usually used for a single qword
*
* NOTE: This assumes the chip address is 64-bit aligned.
*/
static int qib_read_umem64(struct qib_devdata *dd, void __user *uaddr,
u32 regoffs, size_t count)
{
const u64 __iomem *reg_addr;
const u64 __iomem *reg_end;
u32 limit;
int ret;
reg_addr = (const u64 __iomem *)qib_remap_ioaddr32(dd, regoffs, &limit);
if (reg_addr == NULL || limit == 0 || !(dd->flags & QIB_PRESENT)) {
ret = -EINVAL;
goto bail;
}
if (count >= limit)
count = limit;
reg_end = reg_addr + (count / sizeof(u64));
/* not very efficient, but it works for now */
while (reg_addr < reg_end) {
u64 data = readq(reg_addr);
if (copy_to_user(uaddr, &data, sizeof(u64))) {
ret = -EFAULT;
goto bail;
}
reg_addr++;
uaddr += sizeof(u64);
}
ret = 0;
bail:
return ret;
}
/*
* qib_write_umem64 - write a 64-bit quantity to the chip from user space
* @dd: the qlogic_ib device
* @regoffs: the offset from BAR0 (_NOT_ full pointer, anymore)
* @uaddr: the source of the data in user memory
* @count: the number of bytes to copy (multiple of 32 bits)
*
* This is usually used for a single qword
* NOTE: This assumes the chip address is 64-bit aligned.
*/
static int qib_write_umem64(struct qib_devdata *dd, u32 regoffs,
const void __user *uaddr, size_t count)
{
u64 __iomem *reg_addr;
const u64 __iomem *reg_end;
u32 limit;
int ret;
reg_addr = (u64 __iomem *)qib_remap_ioaddr32(dd, regoffs, &limit);
if (reg_addr == NULL || limit == 0 || !(dd->flags & QIB_PRESENT)) {
ret = -EINVAL;
goto bail;
}
if (count >= limit)
count = limit;
reg_end = reg_addr + (count / sizeof(u64));
/* not very efficient, but it works for now */
while (reg_addr < reg_end) {
u64 data;
if (copy_from_user(&data, uaddr, sizeof(data))) {
ret = -EFAULT;
goto bail;
}
writeq(data, reg_addr);
reg_addr++;
uaddr += sizeof(u64);
}
ret = 0;
bail:
return ret;
}
/*
* qib_read_umem32 - read a 32-bit quantity from the chip into user space
* @dd: the qlogic_ib device
* @uaddr: the location to store the data in user memory
* @regoffs: the offset from BAR0 (_NOT_ full pointer, anymore)
* @count: number of bytes to copy
*
* read 32 bit values, not 64 bit; for memories that only
* support 32 bit reads; usually a single dword.
*/
static int qib_read_umem32(struct qib_devdata *dd, void __user *uaddr,
u32 regoffs, size_t count)
{
const u32 __iomem *reg_addr;
const u32 __iomem *reg_end;
u32 limit;
int ret;
reg_addr = qib_remap_ioaddr32(dd, regoffs, &limit);
if (reg_addr == NULL || limit == 0 || !(dd->flags & QIB_PRESENT)) {
ret = -EINVAL;
goto bail;
}
if (count >= limit)
count = limit;
reg_end = reg_addr + (count / sizeof(u32));
/* not very efficient, but it works for now */
while (reg_addr < reg_end) {
u32 data = readl(reg_addr);
if (copy_to_user(uaddr, &data, sizeof(data))) {
ret = -EFAULT;
goto bail;
}
reg_addr++;
uaddr += sizeof(u32);
}
ret = 0;
bail:
return ret;
}
/*
* qib_write_umem32 - write a 32-bit quantity to the chip from user space
* @dd: the qlogic_ib device
* @regoffs: the offset from BAR0 (_NOT_ full pointer, anymore)
* @uaddr: the source of the data in user memory
* @count: number of bytes to copy
*
* write 32 bit values, not 64 bit; for memories that only
* support 32 bit write; usually a single dword.
*/
static int qib_write_umem32(struct qib_devdata *dd, u32 regoffs,
const void __user *uaddr, size_t count)
{
u32 __iomem *reg_addr;
const u32 __iomem *reg_end;
u32 limit;
int ret;
reg_addr = qib_remap_ioaddr32(dd, regoffs, &limit);
if (reg_addr == NULL || limit == 0 || !(dd->flags & QIB_PRESENT)) {
ret = -EINVAL;
goto bail;
}
if (count >= limit)
count = limit;
reg_end = reg_addr + (count / sizeof(u32));
while (reg_addr < reg_end) {
u32 data;
if (copy_from_user(&data, uaddr, sizeof(data))) {
ret = -EFAULT;
goto bail;
}
writel(data, reg_addr);
reg_addr++;
uaddr += sizeof(u32);
}
ret = 0;
bail:
return ret;
}
static int qib_diag_open(struct inode *in, struct file *fp)
{
int unit = iminor(in) - QIB_DIAG_MINOR_BASE;
struct qib_devdata *dd;
struct qib_diag_client *dc;
int ret;
mutex_lock(&qib_mutex);
dd = qib_lookup(unit);
if (dd == NULL || !(dd->flags & QIB_PRESENT) ||
!dd->kregbase) {
ret = -ENODEV;
goto bail;
}
dc = get_client(dd);
if (!dc) {
ret = -ENOMEM;
goto bail;
}
dc->next = dd->diag_client;
dd->diag_client = dc;
fp->private_data = dc;
ret = 0;
bail:
mutex_unlock(&qib_mutex);
return ret;
}
/**
* qib_diagpkt_write - write an IB packet
* @fp: the diag data device file pointer
* @data: qib_diag_pkt structure saying where to get the packet
* @count: size of data to write
* @off: unused by this code
*/
static ssize_t qib_diagpkt_write(struct file *fp,
const char __user *data,
size_t count, loff_t *off)
{
u32 __iomem *piobuf;
u32 plen, pbufn, maxlen_reserve;
struct qib_diag_xpkt dp;
u32 *tmpbuf = NULL;
struct qib_devdata *dd;
struct qib_pportdata *ppd;
ssize_t ret = 0;
if (count != sizeof(dp)) {
ret = -EINVAL;
goto bail;
}
if (copy_from_user(&dp, data, sizeof(dp))) {
ret = -EFAULT;
goto bail;
}
dd = qib_lookup(dp.unit);
if (!dd || !(dd->flags & QIB_PRESENT) || !dd->kregbase) {
ret = -ENODEV;
goto bail;
}
if (!(dd->flags & QIB_INITTED)) {
/* no hardware, freeze, etc. */
ret = -ENODEV;
goto bail;
}
if (dp.version != _DIAG_XPKT_VERS) {
qib_dev_err(dd, "Invalid version %u for diagpkt_write\n",
dp.version);
ret = -EINVAL;
goto bail;
}
/* send count must be an exact number of dwords */
if (dp.len & 3) {
ret = -EINVAL;
goto bail;
}
if (!dp.port || dp.port > dd->num_pports) {
ret = -EINVAL;
goto bail;
}
ppd = &dd->pport[dp.port - 1];
/*
* need total length before first word written, plus 2 Dwords. One Dword
* is for padding so we get the full user data when not aligned on
* a word boundary. The other Dword is to make sure we have room for the
* ICRC which gets tacked on later.
*/
maxlen_reserve = 2 * sizeof(u32);
if (dp.len > ppd->ibmaxlen - maxlen_reserve) {
ret = -EINVAL;
goto bail;
}
plen = sizeof(u32) + dp.len;
tmpbuf = vmalloc(plen);
if (!tmpbuf) {
qib_devinfo(dd->pcidev,
"Unable to allocate tmp buffer, failing\n");
ret = -ENOMEM;
goto bail;
}
if (copy_from_user(tmpbuf,
(const void __user *) (unsigned long) dp.data,
dp.len)) {
ret = -EFAULT;
goto bail;
}
plen >>= 2; /* in dwords */
if (dp.pbc_wd == 0)
dp.pbc_wd = plen;
piobuf = dd->f_getsendbuf(ppd, dp.pbc_wd, &pbufn);
if (!piobuf) {
ret = -EBUSY;
goto bail;
}
/* disarm it just to be extra sure */
dd->f_sendctrl(dd->pport, QIB_SENDCTRL_DISARM_BUF(pbufn));
/* disable header check on pbufn for this packet */
dd->f_txchk_change(dd, pbufn, 1, TXCHK_CHG_TYPE_DIS1, NULL);
writeq(dp.pbc_wd, piobuf);
/*
* Copy all but the trigger word, then flush, so it's written
* to chip before trigger word, then write trigger word, then
* flush again, so packet is sent.
*/
if (dd->flags & QIB_PIO_FLUSH_WC) {
qib_flush_wc();
qib_pio_copy(piobuf + 2, tmpbuf, plen - 1);
qib_flush_wc();
__raw_writel(tmpbuf[plen - 1], piobuf + plen + 1);
} else
qib_pio_copy(piobuf + 2, tmpbuf, plen);
if (dd->flags & QIB_USE_SPCL_TRIG) {
u32 spcl_off = (pbufn >= dd->piobcnt2k) ? 2047 : 1023;
qib_flush_wc();
__raw_writel(0xaebecede, piobuf + spcl_off);
}
/*
* Ensure buffer is written to the chip, then re-enable
* header checks (if supported by chip). The txchk
* code will ensure seen by chip before returning.
*/
qib_flush_wc();
qib_sendbuf_done(dd, pbufn);
dd->f_txchk_change(dd, pbufn, 1, TXCHK_CHG_TYPE_ENAB1, NULL);
ret = sizeof(dp);
bail:
vfree(tmpbuf);
return ret;
}
static int qib_diag_release(struct inode *in, struct file *fp)
{
mutex_lock(&qib_mutex);
return_client(fp->private_data);
fp->private_data = NULL;
mutex_unlock(&qib_mutex);
return 0;
}
/*
* Chip-specific code calls to register its interest in
* a specific range.
*/
struct diag_observer_list_elt {
struct diag_observer_list_elt *next;
const struct diag_observer *op;
};
int qib_register_observer(struct qib_devdata *dd,
const struct diag_observer *op)
{
struct diag_observer_list_elt *olp;
unsigned long flags;
if (!dd || !op)
return -EINVAL;
olp = vmalloc(sizeof(*olp));
if (!olp) {
pr_err("vmalloc for observer failed\n");
return -ENOMEM;
}
spin_lock_irqsave(&dd->qib_diag_trans_lock, flags);
olp->op = op;
olp->next = dd->diag_observer_list;
dd->diag_observer_list = olp;
spin_unlock_irqrestore(&dd->qib_diag_trans_lock, flags);
return 0;
}
/* Remove all registered observers when device is closed */
static void qib_unregister_observers(struct qib_devdata *dd)
{
struct diag_observer_list_elt *olp;
unsigned long flags;
spin_lock_irqsave(&dd->qib_diag_trans_lock, flags);
olp = dd->diag_observer_list;
while (olp) {
/* Pop one observer, let go of lock */
dd->diag_observer_list = olp->next;
spin_unlock_irqrestore(&dd->qib_diag_trans_lock, flags);
vfree(olp);
/* try again. */
spin_lock_irqsave(&dd->qib_diag_trans_lock, flags);
olp = dd->diag_observer_list;
}
spin_unlock_irqrestore(&dd->qib_diag_trans_lock, flags);
}
/*
* Find the observer, if any, for the specified address. Initial implementation
* is simple stack of observers. This must be called with diag transaction
* lock held.
*/
static const struct diag_observer *diag_get_observer(struct qib_devdata *dd,
u32 addr)
{
struct diag_observer_list_elt *olp;
const struct diag_observer *op = NULL;
olp = dd->diag_observer_list;
while (olp) {
op = olp->op;
if (addr >= op->bottom && addr <= op->top)
break;
olp = olp->next;
}
if (!olp)
op = NULL;
return op;
}
static ssize_t qib_diag_read(struct file *fp, char __user *data,
size_t count, loff_t *off)
{
struct qib_diag_client *dc = fp->private_data;
struct qib_devdata *dd = dc->dd;
void __iomem *kreg_base;
ssize_t ret;
if (dc->pid != current->pid) {
ret = -EPERM;
goto bail;
}
kreg_base = dd->kregbase;
if (count == 0)
ret = 0;
else if ((count % 4) || (*off % 4))
/* address or length is not 32-bit aligned, hence invalid */
ret = -EINVAL;
else if (dc->state < READY && (*off || count != 8))
ret = -EINVAL; /* prevent cat /dev/qib_diag* */
else {
unsigned long flags;
u64 data64 = 0;
int use_32;
const struct diag_observer *op;
use_32 = (count % 8) || (*off % 8);
ret = -1;
spin_lock_irqsave(&dd->qib_diag_trans_lock, flags);
/*
* Check for observer on this address range.
* we only support a single 32 or 64-bit read
* via observer, currently.
*/
op = diag_get_observer(dd, *off);
if (op) {
u32 offset = *off;
ret = op->hook(dd, op, offset, &data64, 0, use_32);
}
/*
* We need to release lock before any copy_to_user(),
* whether implicit in qib_read_umem* or explicit below.
*/
spin_unlock_irqrestore(&dd->qib_diag_trans_lock, flags);
if (!op) {
if (use_32)
/*
* Address or length is not 64-bit aligned;
* do 32-bit rd
*/
ret = qib_read_umem32(dd, data, (u32) *off,
count);
else
ret = qib_read_umem64(dd, data, (u32) *off,
count);
} else if (ret == count) {
/* Below finishes case where observer existed */
ret = copy_to_user(data, &data64, use_32 ?
sizeof(u32) : sizeof(u64));
if (ret)
ret = -EFAULT;
}
}
if (ret >= 0) {
*off += count;
ret = count;
if (dc->state == OPENED)
dc->state = INIT;
}
bail:
return ret;
}
static ssize_t qib_diag_write(struct file *fp, const char __user *data,
size_t count, loff_t *off)
{
struct qib_diag_client *dc = fp->private_data;
struct qib_devdata *dd = dc->dd;
void __iomem *kreg_base;
ssize_t ret;
if (dc->pid != current->pid) {
ret = -EPERM;
goto bail;
}
kreg_base = dd->kregbase;
if (count == 0)
ret = 0;
else if ((count % 4) || (*off % 4))
/* address or length is not 32-bit aligned, hence invalid */
ret = -EINVAL;
else if (dc->state < READY &&
((*off || count != 8) || dc->state != INIT))
/* No writes except second-step of init seq */
ret = -EINVAL; /* before any other write allowed */
else {
unsigned long flags;
const struct diag_observer *op = NULL;
int use_32 = (count % 8) || (*off % 8);
/*
* Check for observer on this address range.
* We only support a single 32 or 64-bit write
* via observer, currently. This helps, because
* we would otherwise have to jump through hoops
* to make "diag transaction" meaningful when we
* cannot do a copy_from_user while holding the lock.
*/
if (count == 4 || count == 8) {
u64 data64;
u32 offset = *off;
ret = copy_from_user(&data64, data, count);
if (ret) {
ret = -EFAULT;
goto bail;
}
spin_lock_irqsave(&dd->qib_diag_trans_lock, flags);
op = diag_get_observer(dd, *off);
if (op)
ret = op->hook(dd, op, offset, &data64, ~0Ull,
use_32);
spin_unlock_irqrestore(&dd->qib_diag_trans_lock, flags);
}
if (!op) {
if (use_32)
/*
* Address or length is not 64-bit aligned;
* do 32-bit write
*/
ret = qib_write_umem32(dd, (u32) *off, data,
count);
else
ret = qib_write_umem64(dd, (u32) *off, data,
count);
}
}
if (ret >= 0) {
*off += count;
ret = count;
if (dc->state == INIT)
dc->state = READY; /* all read/write OK now */
}
bail:
return ret;
}