diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/infiniband/hw/qib/qib_diag.c | 906 |
1 files changed, 906 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/qib/qib_diag.c b/drivers/infiniband/hw/qib/qib_diag.c new file mode 100644 index 000000000..11da796dd --- /dev/null +++ b/drivers/infiniband/hw/qib/qib_diag.c @@ -0,0 +1,906 @@ +/* + * 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) { + ret = -ENOMEM; + goto bail; + } + + if (copy_from_user(tmpbuf, + u64_to_user_ptr(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) + 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; + ssize_t ret; + + if (dc->pid != current->pid) { + ret = -EPERM; + goto bail; + } + + 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; + ssize_t ret; + + if (dc->pid != current->pid) { + ret = -EPERM; + goto bail; + } + + 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; +} |