2008-07-02 15:39:10

by Altobelli, David

[permalink] [raw]
Subject: [PATCH][v5] HP iLO driver

A driver for the HP iLO/iLO2 management processor, which allows userspace
programs to query the management processor. Programs can open a channel
to the device (/dev/hpilo/dXccbN), and use this to send/receive queries.
The O_EXCL open flag is used to indicate that a particular channel cannot
be shared between processes. This driver will replace various packages
HP has shipped, including hprsm and hp-ilo.

v4 -> v5
Converted more macros to inline functions
Reorganized to remove kzalloc under spinlock

v3 -> v4
Removed an upper case variable and some extra parens
Converted some macros to inline functions

v2 -> v3
Moved code from drivers/char to drivers/misc

v1 -> v2
Changed device path to /dev/hpilo/dXccbN.
Removed a volatile from fifobar variable.
Changed ILO_NAME to remove spaces.

Please CC me on any replies, thanks for your time.

Signed-off-by: David Altobelli <[email protected]>
---
Kconfig | 13 +
Makefile | 1
hpilo.c | 766 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
hpilo.h | 189 +++++++++++++++
4 files changed, 969 insertions(+)
diff -urpN linux-2.6.26-rc7.orig/drivers/misc/hpilo.c linux-2.6.26-rc7/drivers/misc/hpilo.c
--- linux-2.6.26-rc7.orig/drivers/misc/hpilo.c 1969-12-31 18:00:00.000000000 -0600
+++ linux-2.6.26-rc7/drivers/misc/hpilo.c 2008-07-02 10:21:00.000000000 -0500
@@ -0,0 +1,766 @@
+/*
+ * Driver for HP iLO/iLO2 management processor.
+ *
+ * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
+ * David Altobelli <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/device.h>
+#include <linux/file.h>
+#include <linux/cdev.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include "hpilo.h"
+
+static struct class *ilo_class;
+static unsigned int ilo_major;
+static char ilo_hwdev[MAX_ILO_DEV];
+
+static inline int get_entry_id(int entry)
+{
+ return (entry & ENTRY_MASK_DESCRIPTOR) >> ENTRY_BITPOS_DESCRIPTOR;
+}
+
+static inline int get_entry_len(int entry)
+{
+ return ((entry & ENTRY_MASK_QWORDS) >> ENTRY_BITPOS_QWORDS) << 3;
+}
+
+static inline int mk_entry(int id, int len)
+{
+ int qlen = len & 7 ? (len >> 3) + 1 : len >> 3;
+ return id << ENTRY_BITPOS_DESCRIPTOR | qlen << ENTRY_BITPOS_QWORDS;
+}
+
+static inline int desc_mem_sz(int nr_entry)
+{
+ return nr_entry << L2_QENTRY_SZ;
+}
+
+/*
+ * FIFO queues, shared with hardware.
+ *
+ * If a queue has empty slots, an entry is added to the queue tail,
+ * and that entry is marked as occupied.
+ * Entries can be dequeued from the head of the list, when the device
+ * has marked the entry as consumed.
+ *
+ * Returns true on successful queue/dequeue, false on failure.
+ */
+static int fifo_enqueue(struct ilo_hwinfo *hw, char *fifobar, int entry)
+{
+ struct fifo *fifo_q = FIFOBARTOHANDLE(fifobar);
+ int ret = 0;
+
+ spin_lock(&hw->fifo_lock);
+ if (!(fifo_q->fifobar[(fifo_q->tail + 1) & fifo_q->imask]
+ & ENTRY_MASK_O)) {
+ fifo_q->fifobar[fifo_q->tail & fifo_q->imask] |=
+ (entry & ENTRY_MASK_NOSTATE) | fifo_q->merge;
+ fifo_q->tail += 1;
+ ret = 1;
+ }
+ spin_unlock(&hw->fifo_lock);
+
+ return ret;
+}
+
+static int fifo_dequeue(struct ilo_hwinfo *hw, char *fifobar, int *entry)
+{
+ struct fifo *fifo_q = FIFOBARTOHANDLE(fifobar);
+ int ret = 0;
+ u64 c;
+
+ spin_lock(&hw->fifo_lock);
+ c = fifo_q->fifobar[fifo_q->head & fifo_q->imask];
+ if (c & ENTRY_MASK_C) {
+ if (entry)
+ *entry = c & ENTRY_MASK_NOSTATE;
+
+ fifo_q->fifobar[fifo_q->head & fifo_q->imask] =
+ (c | ENTRY_MASK) + 1;
+ fifo_q->head += 1;
+ ret = 1;
+ }
+ spin_unlock(&hw->fifo_lock);
+
+ return ret;
+}
+
+static int ilo_pkt_enqueue(struct ilo_hwinfo *hw, struct ccb *ccb,
+ int dir, int id, int len)
+{
+ char *fifobar;
+ int entry;
+
+ if (dir == SENDQ)
+ fifobar = ccb->ccb_u1.send_fifobar;
+ else
+ fifobar = ccb->ccb_u3.recv_fifobar;
+
+ entry = mk_entry(id, len);
+ return fifo_enqueue(hw, fifobar, entry);
+}
+
+static int ilo_pkt_dequeue(struct ilo_hwinfo *hw, struct ccb *ccb,
+ int dir, int *id, int *len, void **pkt)
+{
+ char *fifobar, *desc;
+ int entry = 0, pkt_id = 0;
+ int ret;
+
+ if (dir == SENDQ) {
+ fifobar = ccb->ccb_u1.send_fifobar;
+ desc = ccb->ccb_u2.send_desc;
+ } else {
+ fifobar = ccb->ccb_u3.recv_fifobar;
+ desc = ccb->ccb_u4.recv_desc;
+ }
+
+ ret = fifo_dequeue(hw, fifobar, &entry);
+ if (ret) {
+ pkt_id = get_entry_id(entry);
+ if (id)
+ *id = pkt_id;
+ if (len)
+ *len = get_entry_len(entry);
+ if (pkt)
+ *pkt = (void *)(desc + desc_mem_sz(pkt_id));
+ }
+
+ return ret;
+}
+
+static inline void doorbell_set(struct ccb *ccb)
+{
+ iowrite8(1, ccb->ccb_u5.db_base);
+}
+
+static inline void doorbell_clr(struct ccb *ccb)
+{
+ iowrite8(2, ccb->ccb_u5.db_base);
+}
+static inline int ctrl_set(int l2sz, int idxmask, int desclim)
+{
+ int active = 0, go = 1;
+ return l2sz << CTRL_BITPOS_L2SZ |
+ idxmask << CTRL_BITPOS_FIFOINDEXMASK |
+ desclim << CTRL_BITPOS_DESCLIMIT |
+ active << CTRL_BITPOS_A |
+ go << CTRL_BITPOS_G;
+}
+static void ctrl_setup(struct ccb *ccb, int nr_desc, int l2desc_sz)
+{
+ /* for simplicity, use the same parameters for send and recv ctrls */
+ ccb->send_ctrl = ctrl_set(l2desc_sz, nr_desc-1, nr_desc-1);
+ ccb->recv_ctrl = ctrl_set(l2desc_sz, nr_desc-1, nr_desc-1);
+}
+
+static inline int fifo_sz(int nr_entry)
+{
+ /* size of a fifo is determined by the number of entries it contains */
+ return (nr_entry * sizeof(u64)) + FIFOHANDLESIZE;
+}
+
+static void fifo_setup(void *base_addr, int nr_entry)
+{
+ struct fifo *fifo_q = base_addr;
+ int i;
+
+ /* set up an empty fifo */
+ fifo_q->head = 0;
+ fifo_q->tail = 0;
+ fifo_q->reset = 0;
+ fifo_q->nrents = nr_entry;
+ fifo_q->imask = nr_entry - 1;
+ fifo_q->merge = ENTRY_MASK_O;
+
+ for (i = 0; i < nr_entry; i++)
+ fifo_q->fifobar[i] = 0;
+}
+
+static void ilo_ccb_close(struct pci_dev *pdev, struct ccb_data *data)
+{
+ struct ccb *driver_ccb;
+ struct ccb __iomem *device_ccb;
+ int retries;
+
+ driver_ccb = &data->driver_ccb;
+ device_ccb = data->mapped_ccb;
+
+ /* complicated dance to tell the hw we are stopping */
+ doorbell_clr(driver_ccb);
+ iowrite32(ioread32(&device_ccb->send_ctrl) & ~(1 << CTRL_BITPOS_G),
+ &device_ccb->send_ctrl);
+ iowrite32(ioread32(&device_ccb->recv_ctrl) & ~(1 << CTRL_BITPOS_G),
+ &device_ccb->recv_ctrl);
+
+ /* give iLO some time to process stop request */
+ for (retries = 1000; retries > 0; retries--) {
+ doorbell_set(driver_ccb);
+ udelay(1);
+ if (!(ioread32(&device_ccb->send_ctrl) & (1 << CTRL_BITPOS_A))
+ &&
+ !(ioread32(&device_ccb->recv_ctrl) & (1 << CTRL_BITPOS_A)))
+ break;
+ }
+ if (retries == 0)
+ dev_err(&pdev->dev, "Closing, but controller still active\n");
+
+ /* clear the hw ccb */
+ memset_io(device_ccb, 0, sizeof(struct ccb));
+
+ /* free resources used to back send/recv queues */
+ pci_free_consistent(pdev, data->dma_size, data->dma_va, data->dma_pa);
+}
+
+static int ilo_ccb_open(struct ilo_hwinfo *hw, struct ccb_data *data, int slot)
+{
+ char *dma_va, *dma_pa;
+ int pkt_id, pkt_sz, i, error;
+ struct ccb *driver_ccb, *ilo_ccb;
+ struct pci_dev *pdev;
+
+ driver_ccb = &data->driver_ccb;
+ ilo_ccb = &data->ilo_ccb;
+ pdev = hw->ilo_dev;
+
+ data->dma_size = 2 * fifo_sz(NR_QENTRY) +
+ 2 * desc_mem_sz(NR_QENTRY) +
+ ILO_START_ALIGN + ILO_CACHE_SZ;
+
+ error = -ENOMEM;
+ data->dma_va = pci_alloc_consistent(pdev, data->dma_size,
+ &data->dma_pa);
+ if (!data->dma_va)
+ goto out;
+
+ dma_va = (char *)data->dma_va;
+ dma_pa = (char *)data->dma_pa;
+
+ memset(dma_va, 0, data->dma_size);
+
+ dma_va = (char *)roundup((unsigned long)dma_va, ILO_START_ALIGN);
+ dma_pa = (char *)roundup((unsigned long)dma_pa, ILO_START_ALIGN);
+
+ /*
+ * Create two ccb's, one with virt addrs, one with phys addrs.
+ * Copy the phys addr ccb to device shared mem.
+ */
+ ctrl_setup(driver_ccb, NR_QENTRY, L2_QENTRY_SZ);
+ ctrl_setup(ilo_ccb, NR_QENTRY, L2_QENTRY_SZ);
+
+ fifo_setup(dma_va, NR_QENTRY);
+ driver_ccb->ccb_u1.send_fifobar = dma_va + FIFOHANDLESIZE;
+ ilo_ccb->ccb_u1.send_fifobar = dma_pa + FIFOHANDLESIZE;
+ dma_va += fifo_sz(NR_QENTRY);
+ dma_pa += fifo_sz(NR_QENTRY);
+
+ dma_va = (char *)roundup((unsigned long)dma_va, ILO_CACHE_SZ);
+ dma_pa = (char *)roundup((unsigned long)dma_pa, ILO_CACHE_SZ);
+
+ fifo_setup(dma_va, NR_QENTRY);
+ driver_ccb->ccb_u3.recv_fifobar = dma_va + FIFOHANDLESIZE;
+ ilo_ccb->ccb_u3.recv_fifobar = dma_pa + FIFOHANDLESIZE;
+ dma_va += fifo_sz(NR_QENTRY);
+ dma_pa += fifo_sz(NR_QENTRY);
+
+ driver_ccb->ccb_u2.send_desc = dma_va;
+ ilo_ccb->ccb_u2.send_desc = dma_pa;
+ dma_pa += desc_mem_sz(NR_QENTRY);
+ dma_va += desc_mem_sz(NR_QENTRY);
+
+ driver_ccb->ccb_u4.recv_desc = dma_va;
+ ilo_ccb->ccb_u4.recv_desc = dma_pa;
+
+ driver_ccb->channel = slot;
+ ilo_ccb->channel = slot;
+
+ driver_ccb->ccb_u5.db_base = hw->db_vaddr + (slot << L2_DB_SIZE);
+ ilo_ccb->ccb_u5.db_base = NULL; /* hw ccb's doorbell is not used */
+
+ /* copy the ccb with physical addrs to device memory */
+ data->mapped_ccb = (struct ccb __iomem *)
+ (hw->ram_vaddr + (slot * ILOHW_CCB_SZ));
+ memcpy_toio(data->mapped_ccb, ilo_ccb, sizeof(struct ccb));
+
+ /* put packets on the send and receive queues */
+ pkt_sz = 0;
+ for (pkt_id = 0; pkt_id < NR_QENTRY; pkt_id++) {
+ ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, pkt_sz);
+ doorbell_set(driver_ccb);
+ }
+
+ pkt_sz = desc_mem_sz(1);
+ for (pkt_id = 0; pkt_id < NR_QENTRY; pkt_id++)
+ ilo_pkt_enqueue(hw, driver_ccb, RECVQ, pkt_id, pkt_sz);
+
+ doorbell_clr(driver_ccb);
+
+ /* make sure iLO is really handling requests */
+ for (i = 1000; i > 0; i--) {
+ if (ilo_pkt_dequeue(hw, driver_ccb, SENDQ, &pkt_id, NULL, NULL))
+ break;
+ udelay(1);
+ }
+
+ if (i) {
+ ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, 0);
+ doorbell_set(driver_ccb);
+ } else {
+ dev_err(&pdev->dev, "Open could not dequeue a packet\n");
+ error = -EBUSY;
+ goto free;
+ }
+
+ return 0;
+free:
+ pci_free_consistent(pdev, data->dma_size, data->dma_va, data->dma_pa);
+out:
+ return error;
+}
+
+static inline int is_channel_reset(struct ccb *ccb)
+{
+ /* check for this particular channel needing a reset */
+ return FIFOBARTOHANDLE(ccb->ccb_u1.send_fifobar)->reset;
+}
+
+static inline void set_channel_reset(struct ccb *ccb)
+{
+ /* set a flag indicating this channel needs a reset */
+ FIFOBARTOHANDLE(ccb->ccb_u1.send_fifobar)->reset = 1;
+}
+
+static inline int is_device_reset(struct ilo_hwinfo *hw)
+{
+ /* check for global reset condition */
+ return ioread32(&hw->mmio_vaddr[DB_OUT]) & (1 << DB_RESET);
+}
+
+static inline void clear_device(struct ilo_hwinfo *hw)
+{
+ /* clear the device (reset bits, pending channel entries) */
+ iowrite32(-1, &hw->mmio_vaddr[DB_OUT]);
+}
+
+static void ilo_locked_reset(struct ilo_hwinfo *hw)
+{
+ int slot;
+
+ /*
+ * Mapped memory is zeroed on ilo reset, so set a per ccb flag
+ * to indicate that this ccb needs to be closed and reopened.
+ */
+ for (slot = 0; slot < MAX_CCB; slot++) {
+ if (!hw->ccb_alloc[slot])
+ continue;
+ set_channel_reset(&hw->ccb_alloc[slot]->driver_ccb);
+ }
+
+ clear_device(hw);
+}
+
+static void ilo_reset(struct ilo_hwinfo *hw)
+{
+ spin_lock(&hw->alloc_lock);
+
+ /* reset might have been handled after lock was taken */
+ if (is_device_reset(hw))
+ ilo_locked_reset(hw);
+
+ spin_unlock(&hw->alloc_lock);
+}
+
+static ssize_t ilo_read(struct file *fp, char __user *buf,
+ size_t len, loff_t *off)
+{
+ int err, found, cnt, pkt_id, pkt_len;
+ struct ccb_data *data;
+ struct ccb *driver_ccb;
+ struct ilo_hwinfo *hw;
+ void *pkt;
+
+ data = fp->private_data;
+ driver_ccb = &data->driver_ccb;
+ hw = data->ilo_hw;
+
+ if (is_device_reset(hw) || is_channel_reset(driver_ccb)) {
+ /*
+ * If the device has been reset, applications
+ * need to close and reopen all ccbs.
+ */
+ ilo_reset(hw);
+ return -ENODEV;
+ }
+
+ /*
+ * This function is to be called when data is expected
+ * in the channel, and will return an error if no packet is found
+ * during the loop below. The sleep/retry logic is to allow
+ * applications to call read() immediately post write(),
+ * and give iLO some time to process the sent packet.
+ */
+ cnt = 20;
+ do {
+ /* look for a received packet */
+ found = ilo_pkt_dequeue(hw, driver_ccb, RECVQ, &pkt_id,
+ &pkt_len, &pkt);
+ if (found)
+ break;
+ cnt--;
+ msleep(100);
+ } while (!found && cnt);
+
+ if (!found)
+ return -EAGAIN;
+
+ /* only copy the length of the received packet */
+ if (pkt_len < len)
+ len = pkt_len;
+
+ err = copy_to_user(buf, pkt, len);
+
+ /* return the received packet to the queue */
+ ilo_pkt_enqueue(hw, driver_ccb, RECVQ, pkt_id, desc_mem_sz(1));
+
+ return err ? -EFAULT : len;
+}
+
+static ssize_t ilo_write(struct file *fp, const char __user *buf,
+ size_t len, loff_t *off)
+{
+ int err, pkt_id, pkt_len;
+ struct ccb_data *data;
+ struct ccb *driver_ccb;
+ struct ilo_hwinfo *hw;
+ void *pkt;
+
+ data = fp->private_data;
+ driver_ccb = &data->driver_ccb;
+ hw = data->ilo_hw;
+
+ if (is_device_reset(hw) || is_channel_reset(driver_ccb)) {
+ /*
+ * If the device has been reset, applications
+ * need to close and reopen all ccbs.
+ */
+ ilo_reset(hw);
+ return -ENODEV;
+ }
+
+ /* get a packet to send the user command */
+ if (!ilo_pkt_dequeue(hw, driver_ccb, SENDQ, &pkt_id, &pkt_len, &pkt))
+ return -EBUSY;
+
+ /* limit the length to the length of the packet */
+ if (pkt_len < len)
+ len = pkt_len;
+
+ /* on failure, set the len to 0 to return empty packet to the device */
+ err = copy_from_user(pkt, buf, len);
+ if (err)
+ len = 0;
+
+ /* send the packet */
+ ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, len);
+ doorbell_set(driver_ccb);
+
+ return err ? -EFAULT : len;
+}
+
+static int ilo_close(struct inode *ip, struct file *fp)
+{
+ int slot;
+ struct ccb_data *data;
+ struct ilo_hwinfo *hw;
+
+ slot = iminor(ip) % MAX_CCB;
+ hw = container_of(ip->i_cdev, struct ilo_hwinfo, cdev);
+
+ spin_lock(&hw->alloc_lock);
+
+ if (is_device_reset(hw))
+ ilo_locked_reset(hw);
+
+ if (hw->ccb_alloc[slot]->ccb_cnt == 1) {
+
+ data = fp->private_data;
+
+ ilo_ccb_close(hw->ilo_dev, data);
+
+ kfree(data);
+ hw->ccb_alloc[slot] = NULL;
+ } else
+ hw->ccb_alloc[slot]->ccb_cnt--;
+
+ spin_unlock(&hw->alloc_lock);
+
+ return 0;
+}
+
+static int ilo_open(struct inode *ip, struct file *fp)
+{
+ int slot, error;
+ struct ccb_data *data;
+ struct ilo_hwinfo *hw;
+
+ slot = iminor(ip) % MAX_CCB;
+ hw = container_of(ip->i_cdev, struct ilo_hwinfo, cdev);
+
+ /* new ccb allocation */
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ spin_lock(&hw->alloc_lock);
+
+ if (is_device_reset(hw))
+ ilo_locked_reset(hw);
+
+ /* each fd private_data holds sw/hw view of ccb */
+ if (hw->ccb_alloc[slot] == NULL) {
+ /* create a channel control block for this minor */
+ error = ilo_ccb_open(hw, data, slot);
+ if (!error) {
+ hw->ccb_alloc[slot] = data;
+ hw->ccb_alloc[slot]->ccb_cnt = 1;
+ hw->ccb_alloc[slot]->ccb_excl = fp->f_flags & O_EXCL;
+ hw->ccb_alloc[slot]->ilo_hw = hw;
+ } else
+ kfree(data);
+ } else {
+ kfree(data);
+ if (fp->f_flags & O_EXCL || hw->ccb_alloc[slot]->ccb_excl) {
+ /*
+ * The channel exists, and either this open
+ * or a previous open of this channel wants
+ * exclusive access.
+ */
+ error = -EBUSY;
+ } else {
+ hw->ccb_alloc[slot]->ccb_cnt++;
+ error = 0;
+ }
+ }
+ spin_unlock(&hw->alloc_lock);
+
+ if (!error)
+ fp->private_data = hw->ccb_alloc[slot];
+
+ return error;
+}
+
+static const struct file_operations ilo_fops = {
+ .owner = THIS_MODULE,
+ .read = ilo_read,
+ .write = ilo_write,
+ .open = ilo_open,
+ .release = ilo_close,
+};
+
+static void ilo_unmap_device(struct pci_dev *pdev, struct ilo_hwinfo *hw)
+{
+ pci_iounmap(pdev, hw->db_vaddr);
+ pci_iounmap(pdev, hw->ram_vaddr);
+ pci_iounmap(pdev, hw->mmio_vaddr);
+}
+
+static int __devinit ilo_map_device(struct pci_dev *pdev, struct ilo_hwinfo *hw)
+{
+ int error = -ENOMEM;
+
+ /* map the memory mapped i/o registers */
+ hw->mmio_vaddr = pci_iomap(pdev, 1, 0);
+ if (hw->mmio_vaddr == NULL) {
+ dev_err(&pdev->dev, "Error mapping mmio\n");
+ goto out;
+ }
+
+ /* map the adapter shared memory region */
+ hw->ram_vaddr = pci_iomap(pdev, 2, MAX_CCB * ILOHW_CCB_SZ);
+ if (hw->ram_vaddr == NULL) {
+ dev_err(&pdev->dev, "Error mapping shared mem\n");
+ goto mmio_free;
+ }
+
+ /* map the doorbell aperture */
+ hw->db_vaddr = pci_iomap(pdev, 3, MAX_CCB * ONE_DB_SIZE);
+ if (hw->db_vaddr == NULL) {
+ dev_err(&pdev->dev, "Error mapping doorbell\n");
+ goto ram_free;
+ }
+
+ return 0;
+ram_free:
+ pci_iounmap(pdev, hw->ram_vaddr);
+mmio_free:
+ pci_iounmap(pdev, hw->mmio_vaddr);
+out:
+ return error;
+}
+
+static void ilo_remove(struct pci_dev *pdev)
+{
+ int i, minor;
+ struct ilo_hwinfo *ilo_hw = pci_get_drvdata(pdev);
+
+ clear_device(ilo_hw);
+
+ minor = MINOR(ilo_hw->cdev.dev);
+ for (i = minor; i < minor + MAX_CCB; i++)
+ device_destroy(ilo_class, MKDEV(ilo_major, i));
+
+ cdev_del(&ilo_hw->cdev);
+ ilo_unmap_device(pdev, ilo_hw);
+ pci_release_regions(pdev);
+ pci_disable_device(pdev);
+ kfree(ilo_hw);
+ ilo_hwdev[(minor / MAX_CCB)] = 0;
+}
+
+static int __devinit ilo_probe(struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ int devnum, minor, start, error;
+ struct ilo_hwinfo *ilo_hw;
+
+ /* find a free range for device files */
+ for (devnum = 0; devnum < MAX_ILO_DEV; devnum++) {
+ if (ilo_hwdev[devnum] == 0) {
+ ilo_hwdev[devnum] = 1;
+ break;
+ }
+ }
+
+ if (devnum == MAX_ILO_DEV) {
+ dev_err(&pdev->dev, "Error finding free device\n");
+ return -ENODEV;
+ }
+
+ /* track global allocations for this device */
+ error = -ENOMEM;
+ ilo_hw = kzalloc(sizeof(*ilo_hw), GFP_KERNEL);
+ if (!ilo_hw)
+ goto out;
+
+ ilo_hw->ilo_dev = pdev;
+ spin_lock_init(&ilo_hw->alloc_lock);
+ spin_lock_init(&ilo_hw->fifo_lock);
+
+ error = pci_enable_device(pdev);
+ if (error)
+ goto free;
+
+ pci_set_master(pdev);
+
+ error = pci_request_regions(pdev, ILO_NAME);
+ if (error)
+ goto disable;
+
+ error = ilo_map_device(pdev, ilo_hw);
+ if (error)
+ goto free_regions;
+
+ pci_set_drvdata(pdev, ilo_hw);
+ clear_device(ilo_hw);
+
+ cdev_init(&ilo_hw->cdev, &ilo_fops);
+ ilo_hw->cdev.owner = THIS_MODULE;
+ start = devnum * MAX_CCB;
+ error = cdev_add(&ilo_hw->cdev, MKDEV(ilo_major, start), MAX_CCB);
+ if (error) {
+ dev_err(&pdev->dev, "Could not add cdev\n");
+ goto unmap;
+ }
+
+ for (minor = 0 ; minor < MAX_CCB; minor++) {
+ if (IS_ERR(device_create(ilo_class, &pdev->dev,
+ MKDEV(ilo_major, minor),
+ "hpilo!d%dccb%d", devnum, minor)))
+ dev_err(&pdev->dev, "Could not create files\n");
+ }
+
+ return 0;
+unmap:
+ ilo_unmap_device(pdev, ilo_hw);
+free_regions:
+ pci_release_regions(pdev);
+disable:
+ pci_disable_device(pdev);
+free:
+ kfree(ilo_hw);
+out:
+ ilo_hwdev[devnum] = 0;
+ return error;
+}
+
+static struct pci_device_id ilo_devices[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB204) },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, ilo_devices);
+
+static struct pci_driver ilo_driver = {
+ .name = ILO_NAME,
+ .id_table = ilo_devices,
+ .probe = ilo_probe,
+ .remove = __devexit_p(ilo_remove),
+};
+
+static int __init ilo_init(void)
+{
+ int error;
+ dev_t dev;
+
+ ilo_class = class_create(THIS_MODULE, "iLO");
+ if (IS_ERR(ilo_class)) {
+ error = PTR_ERR(ilo_class);
+ goto out;
+ }
+
+ error = alloc_chrdev_region(&dev, 0, MAX_OPEN, ILO_NAME);
+ if (error)
+ goto class_destroy;
+
+ ilo_major = MAJOR(dev);
+
+ error = pci_register_driver(&ilo_driver);
+ if (error)
+ goto chr_remove;
+
+ return 0;
+chr_remove:
+ unregister_chrdev_region(dev, MAX_OPEN);
+class_destroy:
+ class_destroy(ilo_class);
+out:
+ return error;
+}
+
+static void __exit ilo_exit(void)
+{
+ pci_unregister_driver(&ilo_driver);
+ unregister_chrdev_region(MKDEV(ilo_major, 0), MAX_OPEN);
+ class_destroy(ilo_class);
+}
+
+MODULE_VERSION("0.05");
+MODULE_ALIAS(ILO_NAME);
+MODULE_DESCRIPTION(ILO_NAME);
+MODULE_AUTHOR("David Altobelli <[email protected]>");
+MODULE_LICENSE("GPL v2");
+
+module_init(ilo_init);
+module_exit(ilo_exit);
diff -urpN linux-2.6.26-rc7.orig/drivers/misc/hpilo.h linux-2.6.26-rc7/drivers/misc/hpilo.h
--- linux-2.6.26-rc7.orig/drivers/misc/hpilo.h 1969-12-31 18:00:00.000000000 -0600
+++ linux-2.6.26-rc7/drivers/misc/hpilo.h 2008-07-02 10:21:00.000000000 -0500
@@ -0,0 +1,189 @@
+/*
+ * linux/drivers/char/hpilo.h
+ *
+ * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
+ * David Altobelli <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __HPILO_H
+#define __HPILO_H
+
+#define ILO_NAME "hpilo"
+
+/* max number of open channel control blocks per device, hw limited to 32 */
+#define MAX_CCB 8
+/* max number of supported devices */
+#define MAX_ILO_DEV 1
+/* max number of files */
+#define MAX_OPEN (MAX_CCB * MAX_ILO_DEV)
+
+/*
+ * Per device, used to track global memory allocations.
+ */
+struct ilo_hwinfo {
+ /* mmio registers on device */
+ char __iomem *mmio_vaddr;
+
+ /* doorbell registers on device */
+ char __iomem *db_vaddr;
+
+ /* shared memory on device used for channel control blocks */
+ char __iomem *ram_vaddr;
+
+ /* files corresponding to this device */
+ struct ccb_data *ccb_alloc[MAX_CCB];
+
+ struct pci_dev *ilo_dev;
+
+ spinlock_t alloc_lock;
+ spinlock_t fifo_lock;
+
+ struct cdev cdev;
+};
+
+/* offset from mmio_vaddr */
+#define DB_OUT 0xD4
+/* DB_OUT reset bit */
+#define DB_RESET 26
+
+/*
+ * Channel control block. Used to manage hardware queues.
+ * The format must match hw's version. The hw ccb is 128 bytes,
+ * but the context area shouldn't be touched by the driver.
+ */
+#define ILOSW_CCB_SZ 64
+#define ILOHW_CCB_SZ 128
+struct ccb {
+ union {
+ char *send_fifobar;
+ u64 padding1;
+ } ccb_u1;
+ union {
+ char *send_desc;
+ u64 padding2;
+ } ccb_u2;
+ u64 send_ctrl;
+
+ union {
+ char *recv_fifobar;
+ u64 padding3;
+ } ccb_u3;
+ union {
+ char *recv_desc;
+ u64 padding4;
+ } ccb_u4;
+ u64 recv_ctrl;
+
+ union {
+ char __iomem *db_base;
+ u64 padding5;
+ } ccb_u5;
+
+ u64 channel;
+
+ /* unused context area (64 bytes) */
+};
+
+/* ccb queue parameters */
+#define SENDQ 1
+#define RECVQ 2
+#define NR_QENTRY 4
+#define L2_QENTRY_SZ 12
+
+/* ccb ctrl bitfields */
+#define CTRL_BITPOS_L2SZ 0
+#define CTRL_BITPOS_FIFOINDEXMASK 4
+#define CTRL_BITPOS_DESCLIMIT 18
+#define CTRL_BITPOS_A 30
+#define CTRL_BITPOS_G 31
+
+/* ccb doorbell macros */
+#define L2_DB_SIZE 14
+#define ONE_DB_SIZE (1 << L2_DB_SIZE)
+
+/*
+ * Per fd structure used to track the ccb allocated to that dev file.
+ */
+struct ccb_data {
+ /* software version of ccb, using virtual addrs */
+ struct ccb driver_ccb;
+
+ /* hardware version of ccb, using physical addrs */
+ struct ccb ilo_ccb;
+
+ /* hardware ccb is written to this shared mapped device memory */
+ struct ccb __iomem *mapped_ccb;
+
+ /* dma'able memory used for send/recv queues */
+ void *dma_va;
+ dma_addr_t dma_pa;
+ size_t dma_size;
+
+ /* pointer to hardware device info */
+ struct ilo_hwinfo *ilo_hw;
+
+ /* usage count, to allow for shared ccb's */
+ int ccb_cnt;
+
+ /* open wanted exclusive access to this ccb */
+ int ccb_excl;
+};
+
+/*
+ * FIFO queue structure, shared with hw.
+ */
+#define ILO_START_ALIGN 4096
+#define ILO_CACHE_SZ 128
+struct fifo {
+ u64 nrents; /* user requested number of fifo entries */
+ u64 imask; /* mask to extract valid fifo index */
+ u64 merge; /* O/C bits to merge in during enqueue operation */
+ u64 reset; /* set to non-zero when the target device resets */
+ u8 pad_0[ILO_CACHE_SZ - (sizeof(u64) * 4)];
+
+ u64 head;
+ u8 pad_1[ILO_CACHE_SZ - (sizeof(u64))];
+
+ u64 tail;
+ u8 pad_2[ILO_CACHE_SZ - (sizeof(u64))];
+
+ u64 fifobar[1];
+};
+
+/* convert between struct fifo, and the fifobar, which is saved in the ccb */
+#define FIFOHANDLESIZE (sizeof(struct fifo) - sizeof(u64))
+#define FIFOBARTOHANDLE(_fifo) \
+ ((struct fifo *)(((char *)(_fifo)) - FIFOHANDLESIZE))
+
+/* the number of qwords to consume from the entry descriptor */
+#define ENTRY_BITPOS_QWORDS 0
+/* descriptor index number (within a specified queue) */
+#define ENTRY_BITPOS_DESCRIPTOR 10
+/* state bit, fifo entry consumed by consumer */
+#define ENTRY_BITPOS_C 22
+/* state bit, fifo entry is occupied */
+#define ENTRY_BITPOS_O 23
+
+#define ENTRY_BITS_QWORDS 10
+#define ENTRY_BITS_DESCRIPTOR 12
+#define ENTRY_BITS_C 1
+#define ENTRY_BITS_O 1
+#define ENTRY_BITS_TOTAL \
+ (ENTRY_BITS_C + ENTRY_BITS_O + \
+ ENTRY_BITS_QWORDS + ENTRY_BITS_DESCRIPTOR)
+
+/* extract various entry fields */
+#define ENTRY_MASK ((1 << ENTRY_BITS_TOTAL) - 1)
+#define ENTRY_MASK_C (((1 << ENTRY_BITS_C) - 1) << ENTRY_BITPOS_C)
+#define ENTRY_MASK_O (((1 << ENTRY_BITS_O) - 1) << ENTRY_BITPOS_O)
+#define ENTRY_MASK_QWORDS \
+ (((1 << ENTRY_BITS_QWORDS) - 1) << ENTRY_BITPOS_QWORDS)
+#define ENTRY_MASK_DESCRIPTOR \
+ (((1 << ENTRY_BITS_DESCRIPTOR) - 1) << ENTRY_BITPOS_DESCRIPTOR)
+
+#define ENTRY_MASK_NOSTATE (ENTRY_MASK >> (ENTRY_BITS_C + ENTRY_BITS_O))
+
+#endif /* __HPILO_H */
diff -urpN linux-2.6.26-rc7.orig/drivers/misc/Kconfig linux-2.6.26-rc7/drivers/misc/Kconfig
--- linux-2.6.26-rc7.orig/drivers/misc/Kconfig 2008-06-23 08:43:54.000000000 -0500
+++ linux-2.6.26-rc7/drivers/misc/Kconfig 2008-06-23 08:47:14.000000000 -0500
@@ -391,4 +391,17 @@ config SGI_XP
this feature will allow for direct communication between SSIs
based on a network adapter and DMA messaging.

+config HP_ILO
+ tristate "Channel interface driver for HP iLO/iLO2 processor"
+ default n
+ help
+ The channel interface driver allows applications to communicate
+ with iLO/iLO2 management processors present on HP ProLiant
+ servers. Upon loading, the driver creates /dev/hpilo/dXccbN files,
+ which can be used to gather data from the management processor,
+ via read and write system calls.
+
+ To compile this driver as a module, choose M here: the
+ module will be called hpilo.
+
endif # MISC_DEVICES
diff -urpN linux-2.6.26-rc7.orig/drivers/misc/Makefile linux-2.6.26-rc7/drivers/misc/Makefile
--- linux-2.6.26-rc7.orig/drivers/misc/Makefile 2008-06-23 08:43:54.000000000 -0500
+++ linux-2.6.26-rc7/drivers/misc/Makefile 2008-06-23 08:46:07.000000000 -0500
@@ -26,3 +26,4 @@ obj-$(CONFIG_INTEL_MENLOW) += intel_menl
obj-$(CONFIG_ENCLOSURE_SERVICES) += enclosure.o
obj-$(CONFIG_KGDB_TESTS) += kgdbts.o
obj-$(CONFIG_SGI_XP) += sgi-xp/
+obj-$(CONFIG_HP_ILO) += hpilo.o


2008-07-09 14:38:42

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH][v5] HP iLO driver

On Wed 2008-07-02 09:38:53, David Altobelli wrote:
> A driver for the HP iLO/iLO2 management processor, which allows userspace
> programs to query the management processor. Programs can open a channel
> to the device (/dev/hpilo/dXccbN), and use this to send/receive queries.

No.

It allows proprietary HP app to talk to management processor.

Other programs can't use it because you did not document the
interface.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

2008-07-10 01:25:14

by Andrew Morton

[permalink] [raw]
Subject: Re: [PATCH][v5] HP iLO driver

On Wed, 2 Jul 2008 09:38:53 -0600 David Altobelli <[email protected]> wrote:

> A driver for the HP iLO/iLO2 management processor, which allows userspace
> programs to query the management processor. Programs can open a channel
> to the device (/dev/hpilo/dXccbN), and use this to send/receive queries.
> The O_EXCL open flag is used to indicate that a particular channel cannot
> be shared between processes. This driver will replace various packages
> HP has shipped, including hprsm and hp-ilo.
>
> v4 -> v5
> Converted more macros to inline functions
> Reorganized to remove kzalloc under spinlock
>
> v3 -> v4
> Removed an upper case variable and some extra parens
> Converted some macros to inline functions
>
> v2 -> v3
> Moved code from drivers/char to drivers/misc
>
> v1 -> v2
> Changed device path to /dev/hpilo/dXccbN.
> Removed a volatile from fifobar variable.
> Changed ILO_NAME to remove spaces.
>
>
> ...
>
> +static ssize_t ilo_write(struct file *fp, const char __user *buf,
> + size_t len, loff_t *off)
> +{
> + int err, pkt_id, pkt_len;
> + struct ccb_data *data;
> + struct ccb *driver_ccb;
> + struct ilo_hwinfo *hw;
> + void *pkt;
> +
> + data = fp->private_data;
> + driver_ccb = &data->driver_ccb;
> + hw = data->ilo_hw;
> +
> + if (is_device_reset(hw) || is_channel_reset(driver_ccb)) {
> + /*
> + * If the device has been reset, applications
> + * need to close and reopen all ccbs.
> + */
> + ilo_reset(hw);
> + return -ENODEV;
> + }

Can multiple processes open and write to this "device"? If so, the above
looks awfully racy. Perhaps vfs-level i_mutex coverage will save us on the
write-versus-write side, but not on write-versus-read.

2008-07-10 15:47:43

by Altobelli, David

[permalink] [raw]
Subject: RE: [PATCH][v5] HP iLO driver

Andrew Morton wrote:
> On Wed, 2 Jul 2008 09:38:53 -0600 David Altobelli
> <[email protected]> wrote:
>
>>
>> +static ssize_t ilo_write(struct file *fp, const char __user *buf,
>> + size_t len, loff_t *off)
>> +{
>> + int err, pkt_id, pkt_len;
>> + struct ccb_data *data;
>> + struct ccb *driver_ccb;
>> + struct ilo_hwinfo *hw;
>> + void *pkt;
>> +
>> + data = fp->private_data;
>> + driver_ccb = &data->driver_ccb;
>> + hw = data->ilo_hw;
>> +
>> + if (is_device_reset(hw) || is_channel_reset(driver_ccb)) { +
>> /* + * If the device has been reset, applications
>> + * need to close and reopen all ccbs. + */
>> + ilo_reset(hw);
>> + return -ENODEV;
>> + }
>
> Can multiple processes open and write to this "device"? If so, the
> above looks awfully racy. Perhaps vfs-level i_mutex coverage will
> save us on the write-versus-write side, but not on write-versus-read.

Yes, the channels can be shared.

I'm probably missing the race you are seeing, but is_device_reset()
checks a hardware bit, and this hw bit is only cleared after the flag
checked in is_channel_reset() is set. Multiple processes could get into
ilo_reset(), but that function rechecks the hardware bit after taking a
lock (and I don't believe it could happen, but there is no real downside
to multiple setters of the reset flag). Also, this bit of code is only
there to tell the applications that they need to close and reopen channels,
by returning -ENODEV. Reading/writing from a reset channel will not cause
problems, the read or write will simply not succeed.