linux/drivers/pci/xen-pcifront.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Xen PCI Frontend
*
* Author: Ryan Wilson <hap9@epoch.ncsc.mil>
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <xen/xenbus.h>
#include <xen/events.h>
#include <xen/grant_table.h>
#include <xen/page.h>
#include <linux/spinlock.h>
#include <linux/pci.h>
#include <linux/msi.h>
#include <xen/interface/io/pciif.h>
#include <asm/xen/pci.h>
#include <linux/interrupt.h>
#include <linux/atomic.h>
#include <linux/workqueue.h>
#include <linux/bitops.h>
#include <linux/time.h>
#include <linux/ktime.h>
xen/pvhvm: If xen_platform_pci=0 is set don't blow up (v4). The user has the option of disabling the platform driver: 00:02.0 Unassigned class [ff80]: XenSource, Inc. Xen Platform Device (rev 01) which is used to unplug the emulated drivers (IDE, Realtek 8169, etc) and allow the PV drivers to take over. If the user wishes to disable that they can set: xen_platform_pci=0 (in the guest config file) or xen_emul_unplug=never (on the Linux command line) except it does not work properly. The PV drivers still try to load and since the Xen platform driver is not run - and it has not initialized the grant tables, most of the PV drivers stumble upon: input: Xen Virtual Keyboard as /devices/virtual/input/input5 input: Xen Virtual Pointer as /devices/virtual/input/input6M ------------[ cut here ]------------ kernel BUG at /home/konrad/ssd/konrad/linux/drivers/xen/grant-table.c:1206! invalid opcode: 0000 [#1] SMP Modules linked in: xen_kbdfront(+) xenfs xen_privcmd CPU: 6 PID: 1389 Comm: modprobe Not tainted 3.13.0-rc1upstream-00021-ga6c892b-dirty #1 Hardware name: Xen HVM domU, BIOS 4.4-unstable 11/26/2013 RIP: 0010:[<ffffffff813ddc40>] [<ffffffff813ddc40>] get_free_entries+0x2e0/0x300 Call Trace: [<ffffffff8150d9a3>] ? evdev_connect+0x1e3/0x240 [<ffffffff813ddd0e>] gnttab_grant_foreign_access+0x2e/0x70 [<ffffffffa0010081>] xenkbd_connect_backend+0x41/0x290 [xen_kbdfront] [<ffffffffa0010a12>] xenkbd_probe+0x2f2/0x324 [xen_kbdfront] [<ffffffff813e5757>] xenbus_dev_probe+0x77/0x130 [<ffffffff813e7217>] xenbus_frontend_dev_probe+0x47/0x50 [<ffffffff8145e9a9>] driver_probe_device+0x89/0x230 [<ffffffff8145ebeb>] __driver_attach+0x9b/0xa0 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230 [<ffffffff8145cf1c>] bus_for_each_dev+0x8c/0xb0 [<ffffffff8145e7d9>] driver_attach+0x19/0x20 [<ffffffff8145e260>] bus_add_driver+0x1a0/0x220 [<ffffffff8145f1ff>] driver_register+0x5f/0xf0 [<ffffffff813e55c5>] xenbus_register_driver_common+0x15/0x20 [<ffffffff813e76b3>] xenbus_register_frontend+0x23/0x40 [<ffffffffa0015000>] ? 0xffffffffa0014fff [<ffffffffa001502b>] xenkbd_init+0x2b/0x1000 [xen_kbdfront] [<ffffffff81002049>] do_one_initcall+0x49/0x170 .. snip.. which is hardly nice. This patch fixes this by having each PV driver check for: - if running in PV, then it is fine to execute (as that is their native environment). - if running in HVM, check if user wanted 'xen_emul_unplug=never', in which case bail out and don't load any PV drivers. - if running in HVM, and if PCI device 5853:0001 (xen_platform_pci) does not exist, then bail out and not load PV drivers. - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=ide-disks', then bail out for all PV devices _except_ the block one. Ditto for the network one ('nics'). - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=unnecessary' then load block PV driver, and also setup the legacy IDE paths. In (v3) make it actually load PV drivers. Reported-by: Sander Eikelenboom <linux@eikelenboom.it Reported-by: Anthony PERARD <anthony.perard@citrix.com> Reported-and-Tested-by: Fabio Fantoni <fabio.fantoni@m2r.biz> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v2: Add extra logic to handle the myrid ways 'xen_emul_unplug' can be used per Ian and Stefano suggestion] [v3: Make the unnecessary case work properly] [v4: s/disks/ide-disks/ spotted by Fabio] Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> [for PCI parts] CC: stable@vger.kernel.org
2013-11-26 20:05:40 +00:00
#include <xen/platform_pci.h>
xen/pcifront: Use Xen-SWIOTLB when initting if required. We piggyback on "xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used." functionality to start up the Xen-SWIOTLB if we are hot-plugged. This allows us to bypass the need to supply 'iommu=soft' on the Linux command line (mostly). With this patch, if a user forgot 'iommu=soft' on the command line, and hotplug a PCI device they will get: pcifront pci-0: Installing PCI frontend Warning: only able to allocate 4 MB for software IO TLB software IO TLB [mem 0x2a000000-0x2a3fffff] (4MB) mapped at [ffff88002a000000-ffff88002a3fffff] pcifront pci-0: Creating PCI Frontend Bus 0000:00 pcifront pci-0: PCI host bridge to bus 0000:00 pci_bus 0000:00: root bus resource [io 0x0000-0xffff] pci_bus 0000:00: root bus resource [mem 0x00000000-0xfffffffff] pci 0000:00:00.0: [8086:10d3] type 00 class 0x020000 pci 0000:00:00.0: reg 10: [mem 0xfe5c0000-0xfe5dffff] pci 0000:00:00.0: reg 14: [mem 0xfe500000-0xfe57ffff] pci 0000:00:00.0: reg 18: [io 0xe000-0xe01f] pci 0000:00:00.0: reg 1c: [mem 0xfe5e0000-0xfe5e3fff] pcifront pci-0: claiming resource 0000:00:00.0/0 pcifront pci-0: claiming resource 0000:00:00.0/1 pcifront pci-0: claiming resource 0000:00:00.0/2 pcifront pci-0: claiming resource 0000:00:00.0/3 e1000e: Intel(R) PRO/1000 Network Driver - 2.0.0-k e1000e: Copyright(c) 1999 - 2012 Intel Corporation. e1000e 0000:00:00.0: Disabling ASPM L0s L1 e1000e 0000:00:00.0: enabling device (0000 -> 0002) e1000e 0000:00:00.0: Xen PCI mapped GSI16 to IRQ34 e1000e 0000:00:00.0: (unregistered net_device): Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode e1000e 0000:00:00.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:1b:21:ab:c6:13 e1000e 0000:00:00.0: eth0: Intel(R) PRO/1000 Network Connection e1000e 0000:00:00.0: eth0: MAC: 3, PHY: 8, PBA No: E46981-005 The "Warning only" will go away if one supplies 'iommu=soft' instead as we have a higher chance of being able to allocate large swaths of memory. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-31 10:26:59 +00:00
#include <asm/xen/swiotlb-xen.h>
#define INVALID_GRANT_REF (0)
#define INVALID_EVTCHN (-1)
struct pci_bus_entry {
struct list_head list;
struct pci_bus *bus;
};
#define _PDEVB_op_active (0)
#define PDEVB_op_active (1 << (_PDEVB_op_active))
struct pcifront_device {
struct xenbus_device *xdev;
struct list_head root_buses;
int evtchn;
int gnt_ref;
int irq;
/* Lock this when doing any operations in sh_info */
spinlock_t sh_info_lock;
struct xen_pci_sharedinfo *sh_info;
struct work_struct op_work;
unsigned long flags;
};
struct pcifront_sd {
xen/pcifront: Fix mysterious crashes when NUMA locality information was extracted. Occasionaly PV guests would crash with: pciback 0000:00:00.1: Xen PCI mapped GSI0 to IRQ16 BUG: unable to handle kernel paging request at 0000000d1a8c0be0 .. snip.. <ffffffff8139ce1b>] find_next_bit+0xb/0x10 [<ffffffff81387f22>] cpumask_next_and+0x22/0x40 [<ffffffff813c1ef8>] pci_device_probe+0xb8/0x120 [<ffffffff81529097>] ? driver_sysfs_add+0x77/0xa0 [<ffffffff815293e4>] driver_probe_device+0x1a4/0x2d0 [<ffffffff813c1ddd>] ? pci_match_device+0xdd/0x110 [<ffffffff81529657>] __device_attach_driver+0xa7/0xb0 [<ffffffff815295b0>] ? __driver_attach+0xa0/0xa0 [<ffffffff81527622>] bus_for_each_drv+0x62/0x90 [<ffffffff8152978d>] __device_attach+0xbd/0x110 [<ffffffff815297fb>] device_attach+0xb/0x10 [<ffffffff813b75ac>] pci_bus_add_device+0x3c/0x70 [<ffffffff813b7618>] pci_bus_add_devices+0x38/0x80 [<ffffffff813dc34e>] pcifront_scan_root+0x13e/0x1a0 [<ffffffff817a0692>] pcifront_backend_changed+0x262/0x60b [<ffffffff814644c6>] ? xenbus_gather+0xd6/0x160 [<ffffffff8120900f>] ? put_object+0x2f/0x50 [<ffffffff81465c1d>] xenbus_otherend_changed+0x9d/0xa0 [<ffffffff814678ee>] backend_changed+0xe/0x10 [<ffffffff81463a28>] xenwatch_thread+0xc8/0x190 [<ffffffff810f22f0>] ? woken_wake_function+0x10/0x10 which was the result of two things: When we call pci_scan_root_bus we would pass in 'sd' (sysdata) pointer which was an 'pcifront_sd' structure. However in the pci_device_add it expects that the 'sd' is 'struct sysdata' and sets the dev->node to what is in sd->node (offset 4): set_dev_node(&dev->dev, pcibus_to_node(bus)); __pcibus_to_node(const struct pci_bus *bus) { const struct pci_sysdata *sd = bus->sysdata; return sd->node; } However our structure was pcifront_sd which had nothing at that offset: struct pcifront_sd { int domain; /* 0 4 */ /* XXX 4 bytes hole, try to pack */ struct pcifront_device * pdev; /* 8 8 */ } That is an hole - filled with garbage as we used kmalloc instead of kzalloc (the second problem). This patch fixes the issue by: 1) Use kzalloc to initialize to a well known state. 2) Put 'struct pci_sysdata' at the start of 'pcifront_sd'. That way access to the 'node' will access the right offset. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: <stable@vger.kernel.org> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-02-11 21:10:26 +00:00
struct pci_sysdata sd;
struct pcifront_device *pdev;
};
static inline struct pcifront_device *
pcifront_get_pdev(struct pcifront_sd *sd)
{
return sd->pdev;
}
static inline void pcifront_init_sd(struct pcifront_sd *sd,
unsigned int domain, unsigned int bus,
struct pcifront_device *pdev)
{
xen/pcifront: Fix mysterious crashes when NUMA locality information was extracted. Occasionaly PV guests would crash with: pciback 0000:00:00.1: Xen PCI mapped GSI0 to IRQ16 BUG: unable to handle kernel paging request at 0000000d1a8c0be0 .. snip.. <ffffffff8139ce1b>] find_next_bit+0xb/0x10 [<ffffffff81387f22>] cpumask_next_and+0x22/0x40 [<ffffffff813c1ef8>] pci_device_probe+0xb8/0x120 [<ffffffff81529097>] ? driver_sysfs_add+0x77/0xa0 [<ffffffff815293e4>] driver_probe_device+0x1a4/0x2d0 [<ffffffff813c1ddd>] ? pci_match_device+0xdd/0x110 [<ffffffff81529657>] __device_attach_driver+0xa7/0xb0 [<ffffffff815295b0>] ? __driver_attach+0xa0/0xa0 [<ffffffff81527622>] bus_for_each_drv+0x62/0x90 [<ffffffff8152978d>] __device_attach+0xbd/0x110 [<ffffffff815297fb>] device_attach+0xb/0x10 [<ffffffff813b75ac>] pci_bus_add_device+0x3c/0x70 [<ffffffff813b7618>] pci_bus_add_devices+0x38/0x80 [<ffffffff813dc34e>] pcifront_scan_root+0x13e/0x1a0 [<ffffffff817a0692>] pcifront_backend_changed+0x262/0x60b [<ffffffff814644c6>] ? xenbus_gather+0xd6/0x160 [<ffffffff8120900f>] ? put_object+0x2f/0x50 [<ffffffff81465c1d>] xenbus_otherend_changed+0x9d/0xa0 [<ffffffff814678ee>] backend_changed+0xe/0x10 [<ffffffff81463a28>] xenwatch_thread+0xc8/0x190 [<ffffffff810f22f0>] ? woken_wake_function+0x10/0x10 which was the result of two things: When we call pci_scan_root_bus we would pass in 'sd' (sysdata) pointer which was an 'pcifront_sd' structure. However in the pci_device_add it expects that the 'sd' is 'struct sysdata' and sets the dev->node to what is in sd->node (offset 4): set_dev_node(&dev->dev, pcibus_to_node(bus)); __pcibus_to_node(const struct pci_bus *bus) { const struct pci_sysdata *sd = bus->sysdata; return sd->node; } However our structure was pcifront_sd which had nothing at that offset: struct pcifront_sd { int domain; /* 0 4 */ /* XXX 4 bytes hole, try to pack */ struct pcifront_device * pdev; /* 8 8 */ } That is an hole - filled with garbage as we used kmalloc instead of kzalloc (the second problem). This patch fixes the issue by: 1) Use kzalloc to initialize to a well known state. 2) Put 'struct pci_sysdata' at the start of 'pcifront_sd'. That way access to the 'node' will access the right offset. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: <stable@vger.kernel.org> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-02-11 21:10:26 +00:00
/* Because we do not expose that information via XenBus. */
sd->sd.node = first_online_node;
sd->sd.domain = domain;
sd->pdev = pdev;
}
static DEFINE_SPINLOCK(pcifront_dev_lock);
static struct pcifront_device *pcifront_dev;
static int verbose_request;
module_param(verbose_request, int, 0644);
static int errno_to_pcibios_err(int errno)
{
switch (errno) {
case XEN_PCI_ERR_success:
return PCIBIOS_SUCCESSFUL;
case XEN_PCI_ERR_dev_not_found:
return PCIBIOS_DEVICE_NOT_FOUND;
case XEN_PCI_ERR_invalid_offset:
case XEN_PCI_ERR_op_failed:
return PCIBIOS_BAD_REGISTER_NUMBER;
case XEN_PCI_ERR_not_implemented:
return PCIBIOS_FUNC_NOT_SUPPORTED;
case XEN_PCI_ERR_access_denied:
return PCIBIOS_SET_FAILED;
}
return errno;
}
static inline void schedule_pcifront_aer_op(struct pcifront_device *pdev)
{
if (test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags)
&& !test_and_set_bit(_PDEVB_op_active, &pdev->flags)) {
dev_dbg(&pdev->xdev->dev, "schedule aer frontend job\n");
schedule_work(&pdev->op_work);
}
}
static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op)
{
int err = 0;
struct xen_pci_op *active_op = &pdev->sh_info->op;
unsigned long irq_flags;
evtchn_port_t port = pdev->evtchn;
unsigned irq = pdev->irq;
s64 ns, ns_timeout;
spin_lock_irqsave(&pdev->sh_info_lock, irq_flags);
memcpy(active_op, op, sizeof(struct xen_pci_op));
/* Go */
wmb();
set_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags);
notify_remote_via_evtchn(port);
/*
* We set a poll timeout of 3 seconds but give up on return after
* 2 seconds. It is better to time out too late rather than too early
* (in the latter case we end up continually re-executing poll() with a
* timeout in the past). 1s difference gives plenty of slack for error.
*/
ns_timeout = ktime_get_ns() + 2 * (s64)NSEC_PER_SEC;
xen_clear_irq_pending(irq);
while (test_bit(_XEN_PCIF_active,
(unsigned long *)&pdev->sh_info->flags)) {
xen_poll_irq_timeout(irq, jiffies + 3*HZ);
xen_clear_irq_pending(irq);
ns = ktime_get_ns();
if (ns > ns_timeout) {
dev_err(&pdev->xdev->dev,
"pciback not responding!!!\n");
clear_bit(_XEN_PCIF_active,
(unsigned long *)&pdev->sh_info->flags);
err = XEN_PCI_ERR_dev_not_found;
goto out;
}
}
/*
* We might lose backend service request since we
* reuse same evtchn with pci_conf backend response. So re-schedule
* aer pcifront service.
*/
if (test_bit(_XEN_PCIB_active,
(unsigned long *)&pdev->sh_info->flags)) {
dev_err(&pdev->xdev->dev,
"schedule aer pcifront service\n");
schedule_pcifront_aer_op(pdev);
}
memcpy(op, active_op, sizeof(struct xen_pci_op));
err = op->err;
out:
spin_unlock_irqrestore(&pdev->sh_info_lock, irq_flags);
return err;
}
/* Access to this function is spinlocked in drivers/pci/access.c */
static int pcifront_bus_read(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 *val)
{
int err = 0;
struct xen_pci_op op = {
.cmd = XEN_PCI_OP_conf_read,
.domain = pci_domain_nr(bus),
.bus = bus->number,
.devfn = devfn,
.offset = where,
.size = size,
};
struct pcifront_sd *sd = bus->sysdata;
struct pcifront_device *pdev = pcifront_get_pdev(sd);
if (verbose_request)
dev_info(&pdev->xdev->dev,
"read dev=%04x:%02x:%02x.%d - offset %x size %d\n",
pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
PCI_FUNC(devfn), where, size);
err = do_pci_op(pdev, &op);
if (likely(!err)) {
if (verbose_request)
dev_info(&pdev->xdev->dev, "read got back value %x\n",
op.value);
*val = op.value;
} else if (err == -ENODEV) {
/* No device here, pretend that it just returned 0 */
err = 0;
*val = 0;
}
return errno_to_pcibios_err(err);
}
/* Access to this function is spinlocked in drivers/pci/access.c */
static int pcifront_bus_write(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 val)
{
struct xen_pci_op op = {
.cmd = XEN_PCI_OP_conf_write,
.domain = pci_domain_nr(bus),
.bus = bus->number,
.devfn = devfn,
.offset = where,
.size = size,
.value = val,
};
struct pcifront_sd *sd = bus->sysdata;
struct pcifront_device *pdev = pcifront_get_pdev(sd);
if (verbose_request)
dev_info(&pdev->xdev->dev,
"write dev=%04x:%02x:%02x.%d - "
"offset %x size %d val %x\n",
pci_domain_nr(bus), bus->number,
PCI_SLOT(devfn), PCI_FUNC(devfn), where, size, val);
return errno_to_pcibios_err(do_pci_op(pdev, &op));
}
static struct pci_ops pcifront_bus_ops = {
.read = pcifront_bus_read,
.write = pcifront_bus_write,
};
#ifdef CONFIG_PCI_MSI
static int pci_frontend_enable_msix(struct pci_dev *dev,
int vector[], int nvec)
{
int err;
int i;
struct xen_pci_op op = {
.cmd = XEN_PCI_OP_enable_msix,
.domain = pci_domain_nr(dev->bus),
.bus = dev->bus->number,
.devfn = dev->devfn,
.value = nvec,
};
struct pcifront_sd *sd = dev->bus->sysdata;
struct pcifront_device *pdev = pcifront_get_pdev(sd);
struct msi_desc *entry;
if (nvec > SH_INFO_MAX_VEC) {
pci_err(dev, "too many vectors (0x%x) for PCI frontend:"
" Increase SH_INFO_MAX_VEC\n", nvec);
return -EINVAL;
}
i = 0;
for_each_pci_msi_entry(entry, dev) {
op.msix_entries[i].entry = entry->msi_attrib.entry_nr;
/* Vector is useless at this point. */
op.msix_entries[i].vector = -1;
i++;
}
err = do_pci_op(pdev, &op);
if (likely(!err)) {
if (likely(!op.value)) {
/* we get the result */
for (i = 0; i < nvec; i++) {
if (op.msix_entries[i].vector <= 0) {
pci_warn(dev, "MSI-X entry %d is invalid: %d!\n",
i, op.msix_entries[i].vector);
err = -EINVAL;
vector[i] = -1;
continue;
}
vector[i] = op.msix_entries[i].vector;
}
} else {
pr_info("enable msix get value %x\n", op.value);
err = op.value;
}
} else {
pci_err(dev, "enable msix get err %x\n", err);
}
return err;
}
static void pci_frontend_disable_msix(struct pci_dev *dev)
{
int err;
struct xen_pci_op op = {
.cmd = XEN_PCI_OP_disable_msix,
.domain = pci_domain_nr(dev->bus),
.bus = dev->bus->number,
.devfn = dev->devfn,
};
struct pcifront_sd *sd = dev->bus->sysdata;
struct pcifront_device *pdev = pcifront_get_pdev(sd);
err = do_pci_op(pdev, &op);
/* What should do for error ? */
if (err)
pci_err(dev, "pci_disable_msix get err %x\n", err);
}
static int pci_frontend_enable_msi(struct pci_dev *dev, int vector[])
{
int err;
struct xen_pci_op op = {
.cmd = XEN_PCI_OP_enable_msi,
.domain = pci_domain_nr(dev->bus),
.bus = dev->bus->number,
.devfn = dev->devfn,
};
struct pcifront_sd *sd = dev->bus->sysdata;
struct pcifront_device *pdev = pcifront_get_pdev(sd);
err = do_pci_op(pdev, &op);
if (likely(!err)) {
vector[0] = op.value;
if (op.value <= 0) {
pci_warn(dev, "MSI entry is invalid: %d!\n",
op.value);
err = -EINVAL;
vector[0] = -1;
}
} else {
pci_err(dev, "pci frontend enable msi failed for dev "
"%x:%x\n", op.bus, op.devfn);
err = -EINVAL;
}
return err;
}
static void pci_frontend_disable_msi(struct pci_dev *dev)
{
int err;
struct xen_pci_op op = {
.cmd = XEN_PCI_OP_disable_msi,
.domain = pci_domain_nr(dev->bus),
.bus = dev->bus->number,
.devfn = dev->devfn,
};
struct pcifront_sd *sd = dev->bus->sysdata;
struct pcifront_device *pdev = pcifront_get_pdev(sd);
err = do_pci_op(pdev, &op);
if (err == XEN_PCI_ERR_dev_not_found) {
/* XXX No response from backend, what shall we do? */
pr_info("get no response from backend for disable MSI\n");
return;
}
if (err)
/* how can pciback notify us fail? */
pr_info("get fake response from backend\n");
}
static struct xen_pci_frontend_ops pci_frontend_ops = {
.enable_msi = pci_frontend_enable_msi,
.disable_msi = pci_frontend_disable_msi,
.enable_msix = pci_frontend_enable_msix,
.disable_msix = pci_frontend_disable_msix,
};
static void pci_frontend_registrar(int enable)
{
if (enable)
xen_pci_frontend = &pci_frontend_ops;
else
xen_pci_frontend = NULL;
};
#else
static inline void pci_frontend_registrar(int enable) { };
#endif /* CONFIG_PCI_MSI */
/* Claim resources for the PCI frontend as-is, backend won't allow changes */
static int pcifront_claim_resource(struct pci_dev *dev, void *data)
{
struct pcifront_device *pdev = data;
int i;
struct resource *r;
for (i = 0; i < PCI_NUM_RESOURCES; i++) {
r = &dev->resource[i];
if (!r->parent && r->start && r->flags) {
dev_info(&pdev->xdev->dev, "claiming resource %s/%d\n",
pci_name(dev), i);
if (pci_claim_resource(dev, i)) {
dev_err(&pdev->xdev->dev, "Could not claim resource %s/%d! "
"Device offline. Try using e820_host=1 in the guest config.\n",
pci_name(dev), i);
}
}
}
return 0;
}
static int pcifront_scan_bus(struct pcifront_device *pdev,
unsigned int domain, unsigned int bus,
struct pci_bus *b)
{
struct pci_dev *d;
unsigned int devfn;
/* Scan the bus for functions and add.
* We omit handling of PCI bridge attachment because pciback prevents
* bridges from being exported.
*/
for (devfn = 0; devfn < 0x100; devfn++) {
d = pci_get_slot(b, devfn);
if (d) {
/* Device is already known. */
pci_dev_put(d);
continue;
}
d = pci_scan_single_device(b, devfn);
if (d)
dev_info(&pdev->xdev->dev, "New device on "
"%04x:%02x:%02x.%d found.\n", domain, bus,
PCI_SLOT(devfn), PCI_FUNC(devfn));
}
return 0;
}
static int pcifront_scan_root(struct pcifront_device *pdev,
unsigned int domain, unsigned int bus)
{
struct pci_bus *b;
LIST_HEAD(resources);
struct pcifront_sd *sd = NULL;
struct pci_bus_entry *bus_entry = NULL;
int err = 0;
static struct resource busn_res = {
.start = 0,
.end = 255,
.flags = IORESOURCE_BUS,
};
#ifndef CONFIG_PCI_DOMAINS
if (domain != 0) {
dev_err(&pdev->xdev->dev,
"PCI Root in non-zero PCI Domain! domain=%d\n", domain);
dev_err(&pdev->xdev->dev,
"Please compile with CONFIG_PCI_DOMAINS\n");
err = -EINVAL;
goto err_out;
}
#endif
dev_info(&pdev->xdev->dev, "Creating PCI Frontend Bus %04x:%02x\n",
domain, bus);
xen/pcifront: Fix mysterious crashes when NUMA locality information was extracted. Occasionaly PV guests would crash with: pciback 0000:00:00.1: Xen PCI mapped GSI0 to IRQ16 BUG: unable to handle kernel paging request at 0000000d1a8c0be0 .. snip.. <ffffffff8139ce1b>] find_next_bit+0xb/0x10 [<ffffffff81387f22>] cpumask_next_and+0x22/0x40 [<ffffffff813c1ef8>] pci_device_probe+0xb8/0x120 [<ffffffff81529097>] ? driver_sysfs_add+0x77/0xa0 [<ffffffff815293e4>] driver_probe_device+0x1a4/0x2d0 [<ffffffff813c1ddd>] ? pci_match_device+0xdd/0x110 [<ffffffff81529657>] __device_attach_driver+0xa7/0xb0 [<ffffffff815295b0>] ? __driver_attach+0xa0/0xa0 [<ffffffff81527622>] bus_for_each_drv+0x62/0x90 [<ffffffff8152978d>] __device_attach+0xbd/0x110 [<ffffffff815297fb>] device_attach+0xb/0x10 [<ffffffff813b75ac>] pci_bus_add_device+0x3c/0x70 [<ffffffff813b7618>] pci_bus_add_devices+0x38/0x80 [<ffffffff813dc34e>] pcifront_scan_root+0x13e/0x1a0 [<ffffffff817a0692>] pcifront_backend_changed+0x262/0x60b [<ffffffff814644c6>] ? xenbus_gather+0xd6/0x160 [<ffffffff8120900f>] ? put_object+0x2f/0x50 [<ffffffff81465c1d>] xenbus_otherend_changed+0x9d/0xa0 [<ffffffff814678ee>] backend_changed+0xe/0x10 [<ffffffff81463a28>] xenwatch_thread+0xc8/0x190 [<ffffffff810f22f0>] ? woken_wake_function+0x10/0x10 which was the result of two things: When we call pci_scan_root_bus we would pass in 'sd' (sysdata) pointer which was an 'pcifront_sd' structure. However in the pci_device_add it expects that the 'sd' is 'struct sysdata' and sets the dev->node to what is in sd->node (offset 4): set_dev_node(&dev->dev, pcibus_to_node(bus)); __pcibus_to_node(const struct pci_bus *bus) { const struct pci_sysdata *sd = bus->sysdata; return sd->node; } However our structure was pcifront_sd which had nothing at that offset: struct pcifront_sd { int domain; /* 0 4 */ /* XXX 4 bytes hole, try to pack */ struct pcifront_device * pdev; /* 8 8 */ } That is an hole - filled with garbage as we used kmalloc instead of kzalloc (the second problem). This patch fixes the issue by: 1) Use kzalloc to initialize to a well known state. 2) Put 'struct pci_sysdata' at the start of 'pcifront_sd'. That way access to the 'node' will access the right offset. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: <stable@vger.kernel.org> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-02-11 21:10:26 +00:00
bus_entry = kzalloc(sizeof(*bus_entry), GFP_KERNEL);
sd = kzalloc(sizeof(*sd), GFP_KERNEL);
if (!bus_entry || !sd) {
err = -ENOMEM;
goto err_out;
}
pci_add_resource(&resources, &ioport_resource);
pci_add_resource(&resources, &iomem_resource);
pci_add_resource(&resources, &busn_res);
pcifront_init_sd(sd, domain, bus, pdev);
pci_lock_rescan_remove();
b = pci_scan_root_bus(&pdev->xdev->dev, bus,
&pcifront_bus_ops, sd, &resources);
if (!b) {
dev_err(&pdev->xdev->dev,
"Error creating PCI Frontend Bus!\n");
err = -ENOMEM;
pci_unlock_rescan_remove();
pci_free_resource_list(&resources);
goto err_out;
}
bus_entry->bus = b;
list_add(&bus_entry->list, &pdev->root_buses);
/* pci_scan_root_bus skips devices which do not have a
* devfn==0. The pcifront_scan_bus enumerates all devfn. */
err = pcifront_scan_bus(pdev, domain, bus, b);
/* Claim resources before going "live" with our devices */
pci_walk_bus(b, pcifront_claim_resource, pdev);
/* Create SysFS and notify udev of the devices. Aka: "going live" */
pci_bus_add_devices(b);
pci_unlock_rescan_remove();
return err;
err_out:
kfree(bus_entry);
kfree(sd);
return err;
}
static int pcifront_rescan_root(struct pcifront_device *pdev,
unsigned int domain, unsigned int bus)
{
int err;
struct pci_bus *b;
#ifndef CONFIG_PCI_DOMAINS
if (domain != 0) {
dev_err(&pdev->xdev->dev,
"PCI Root in non-zero PCI Domain! domain=%d\n", domain);
dev_err(&pdev->xdev->dev,
"Please compile with CONFIG_PCI_DOMAINS\n");
return -EINVAL;
}
#endif
dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
domain, bus);
b = pci_find_bus(domain, bus);
if (!b)
/* If the bus is unknown, create it. */
return pcifront_scan_root(pdev, domain, bus);
err = pcifront_scan_bus(pdev, domain, bus, b);
/* Claim resources before going "live" with our devices */
pci_walk_bus(b, pcifront_claim_resource, pdev);
/* Create SysFS and notify udev of the devices. Aka: "going live" */
pci_bus_add_devices(b);
return err;
}
static void free_root_bus_devs(struct pci_bus *bus)
{
struct pci_dev *dev;
while (!list_empty(&bus->devices)) {
dev = container_of(bus->devices.next, struct pci_dev,
bus_list);
pci_dbg(dev, "removing device\n");
pci_stop_and_remove_bus_device(dev);
}
}
static void pcifront_free_roots(struct pcifront_device *pdev)
{
struct pci_bus_entry *bus_entry, *t;
dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n");
pci_lock_rescan_remove();
list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) {
list_del(&bus_entry->list);
free_root_bus_devs(bus_entry->bus);
kfree(bus_entry->bus->sysdata);
device_unregister(bus_entry->bus->bridge);
pci_remove_bus(bus_entry->bus);
kfree(bus_entry);
}
pci_unlock_rescan_remove();
}
static pci_ers_result_t pcifront_common_process(int cmd,
struct pcifront_device *pdev,
pci_channel_state_t state)
{
pci_ers_result_t result;
struct pci_driver *pdrv;
int bus = pdev->sh_info->aer_op.bus;
int devfn = pdev->sh_info->aer_op.devfn;
int domain = pdev->sh_info->aer_op.domain;
struct pci_dev *pcidev;
int flag = 0;
dev_dbg(&pdev->xdev->dev,
"pcifront AER process: cmd %x (bus:%x, devfn%x)",
cmd, bus, devfn);
result = PCI_ERS_RESULT_NONE;
pcidev = pci_get_domain_bus_and_slot(domain, bus, devfn);
if (!pcidev || !pcidev->driver) {
dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n");
pci_dev_put(pcidev);
return result;
}
pdrv = pcidev->driver;
if (pdrv) {
if (pdrv->err_handler && pdrv->err_handler->error_detected) {
pci_dbg(pcidev, "trying to call AER service\n");
if (pcidev) {
flag = 1;
switch (cmd) {
case XEN_PCI_OP_aer_detected:
result = pdrv->err_handler->
error_detected(pcidev, state);
break;
case XEN_PCI_OP_aer_mmio:
result = pdrv->err_handler->
mmio_enabled(pcidev);
break;
case XEN_PCI_OP_aer_slotreset:
result = pdrv->err_handler->
slot_reset(pcidev);
break;
case XEN_PCI_OP_aer_resume:
pdrv->err_handler->resume(pcidev);
break;
default:
dev_err(&pdev->xdev->dev,
"bad request in aer recovery "
"operation!\n");
}
}
}
}
if (!flag)
result = PCI_ERS_RESULT_NONE;
return result;
}
static void pcifront_do_aer(struct work_struct *data)
{
struct pcifront_device *pdev =
container_of(data, struct pcifront_device, op_work);
int cmd = pdev->sh_info->aer_op.cmd;
pci_channel_state_t state =
(pci_channel_state_t)pdev->sh_info->aer_op.err;
/*If a pci_conf op is in progress,
we have to wait until it is done before service aer op*/
dev_dbg(&pdev->xdev->dev,
"pcifront service aer bus %x devfn %x\n",
pdev->sh_info->aer_op.bus, pdev->sh_info->aer_op.devfn);
pdev->sh_info->aer_op.err = pcifront_common_process(cmd, pdev, state);
/* Post the operation to the guest. */
wmb();
clear_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags);
notify_remote_via_evtchn(pdev->evtchn);
/*in case of we lost an aer request in four lines time_window*/
smp_mb__before_atomic();
clear_bit(_PDEVB_op_active, &pdev->flags);
smp_mb__after_atomic();
schedule_pcifront_aer_op(pdev);
}
static irqreturn_t pcifront_handler_aer(int irq, void *dev)
{
struct pcifront_device *pdev = dev;
schedule_pcifront_aer_op(pdev);
return IRQ_HANDLED;
}
xen/pcifront: Use Xen-SWIOTLB when initting if required. We piggyback on "xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used." functionality to start up the Xen-SWIOTLB if we are hot-plugged. This allows us to bypass the need to supply 'iommu=soft' on the Linux command line (mostly). With this patch, if a user forgot 'iommu=soft' on the command line, and hotplug a PCI device they will get: pcifront pci-0: Installing PCI frontend Warning: only able to allocate 4 MB for software IO TLB software IO TLB [mem 0x2a000000-0x2a3fffff] (4MB) mapped at [ffff88002a000000-ffff88002a3fffff] pcifront pci-0: Creating PCI Frontend Bus 0000:00 pcifront pci-0: PCI host bridge to bus 0000:00 pci_bus 0000:00: root bus resource [io 0x0000-0xffff] pci_bus 0000:00: root bus resource [mem 0x00000000-0xfffffffff] pci 0000:00:00.0: [8086:10d3] type 00 class 0x020000 pci 0000:00:00.0: reg 10: [mem 0xfe5c0000-0xfe5dffff] pci 0000:00:00.0: reg 14: [mem 0xfe500000-0xfe57ffff] pci 0000:00:00.0: reg 18: [io 0xe000-0xe01f] pci 0000:00:00.0: reg 1c: [mem 0xfe5e0000-0xfe5e3fff] pcifront pci-0: claiming resource 0000:00:00.0/0 pcifront pci-0: claiming resource 0000:00:00.0/1 pcifront pci-0: claiming resource 0000:00:00.0/2 pcifront pci-0: claiming resource 0000:00:00.0/3 e1000e: Intel(R) PRO/1000 Network Driver - 2.0.0-k e1000e: Copyright(c) 1999 - 2012 Intel Corporation. e1000e 0000:00:00.0: Disabling ASPM L0s L1 e1000e 0000:00:00.0: enabling device (0000 -> 0002) e1000e 0000:00:00.0: Xen PCI mapped GSI16 to IRQ34 e1000e 0000:00:00.0: (unregistered net_device): Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode e1000e 0000:00:00.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:1b:21:ab:c6:13 e1000e 0000:00:00.0: eth0: Intel(R) PRO/1000 Network Connection e1000e 0000:00:00.0: eth0: MAC: 3, PHY: 8, PBA No: E46981-005 The "Warning only" will go away if one supplies 'iommu=soft' instead as we have a higher chance of being able to allocate large swaths of memory. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-31 10:26:59 +00:00
static int pcifront_connect_and_init_dma(struct pcifront_device *pdev)
{
int err = 0;
spin_lock(&pcifront_dev_lock);
if (!pcifront_dev) {
dev_info(&pdev->xdev->dev, "Installing PCI frontend\n");
pcifront_dev = pdev;
xen/pcifront: Deal with toolstack missing 'XenbusStateClosing' state. There are two tool-stack that can instruct the Xen PCI frontend and backend to change states: 'xm' (Python code with a daemon), and 'xl' (C library - does not keep state changes). With the 'xm', the path to disconnect a single PCI device (xm pci-detach <guest> <BDF>) is: 4(Connected)->7(Reconfiguring*)-> 8(Reconfigured)-> 4(Connected)->5(Closing*). The * is for states that the tool-stack sets. For 'xl', it is similar: 4(Connected)->7(Reconfiguring*)-> 8(Reconfigured)-> 4(Connected) Both of them also tear down the XenBus structure, so the backend state ends up going in the 3(Initialised) and calls pcifront_xenbus_remove. When a PCI device is plugged back in (xm pci-attach <guest> <BDF>) both of them follow the same pattern: 2(InitWait*), 3(Initialized*), 4(Connected*)->4(Connected). [xen-pcifront ignores the 2,3 state changes and only acts when 4 (Connected) has been reached] Note that this is for a _single_ PCI device. If there were two PCI devices and only one was disconnected 'xm' would show the same state changes. The problem is that git commit 3d925320e9e2de162bd138bf97816bda8c3f71be ("xen/pcifront: Use Xen-SWIOTLB when initting if required") introduced a mechanism to initialize the SWIOTLB when the Xen PCI front moves to Connected state. It also had some aggressive seatbelt code check that would warn the user if one tried to change to Connected state without hitting first the Closing state: pcifront pci-0: PCI frontend already installed! However, that code can be relaxed and we can continue on working even if the frontend is instructed to be the 'Connected' state with no devices and then gets tickled to be in 'Connected' state again. In other words, this 4(Connected)->5(Closing)->4(Connected) state was expected, while 4(Connected)->.... anything but 5(Closing)->4(Connected) was not. This patch removes that aggressive check and allows Xen pcifront to work with the 'xl' toolstack (for one or more PCI devices) and with 'xm' toolstack (for more than two PCI devices). Acked-by: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-pci@vger.kernel.org Cc: stable@vger.kernel.org [v2: Added in the description about two PCI devices] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10 20:48:09 +00:00
} else
err = -EEXIST;
xen/pcifront: Deal with toolstack missing 'XenbusStateClosing' state. There are two tool-stack that can instruct the Xen PCI frontend and backend to change states: 'xm' (Python code with a daemon), and 'xl' (C library - does not keep state changes). With the 'xm', the path to disconnect a single PCI device (xm pci-detach <guest> <BDF>) is: 4(Connected)->7(Reconfiguring*)-> 8(Reconfigured)-> 4(Connected)->5(Closing*). The * is for states that the tool-stack sets. For 'xl', it is similar: 4(Connected)->7(Reconfiguring*)-> 8(Reconfigured)-> 4(Connected) Both of them also tear down the XenBus structure, so the backend state ends up going in the 3(Initialised) and calls pcifront_xenbus_remove. When a PCI device is plugged back in (xm pci-attach <guest> <BDF>) both of them follow the same pattern: 2(InitWait*), 3(Initialized*), 4(Connected*)->4(Connected). [xen-pcifront ignores the 2,3 state changes and only acts when 4 (Connected) has been reached] Note that this is for a _single_ PCI device. If there were two PCI devices and only one was disconnected 'xm' would show the same state changes. The problem is that git commit 3d925320e9e2de162bd138bf97816bda8c3f71be ("xen/pcifront: Use Xen-SWIOTLB when initting if required") introduced a mechanism to initialize the SWIOTLB when the Xen PCI front moves to Connected state. It also had some aggressive seatbelt code check that would warn the user if one tried to change to Connected state without hitting first the Closing state: pcifront pci-0: PCI frontend already installed! However, that code can be relaxed and we can continue on working even if the frontend is instructed to be the 'Connected' state with no devices and then gets tickled to be in 'Connected' state again. In other words, this 4(Connected)->5(Closing)->4(Connected) state was expected, while 4(Connected)->.... anything but 5(Closing)->4(Connected) was not. This patch removes that aggressive check and allows Xen pcifront to work with the 'xl' toolstack (for one or more PCI devices) and with 'xm' toolstack (for more than two PCI devices). Acked-by: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-pci@vger.kernel.org Cc: stable@vger.kernel.org [v2: Added in the description about two PCI devices] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10 20:48:09 +00:00
spin_unlock(&pcifront_dev_lock);
xen/pcifront: Use Xen-SWIOTLB when initting if required. We piggyback on "xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used." functionality to start up the Xen-SWIOTLB if we are hot-plugged. This allows us to bypass the need to supply 'iommu=soft' on the Linux command line (mostly). With this patch, if a user forgot 'iommu=soft' on the command line, and hotplug a PCI device they will get: pcifront pci-0: Installing PCI frontend Warning: only able to allocate 4 MB for software IO TLB software IO TLB [mem 0x2a000000-0x2a3fffff] (4MB) mapped at [ffff88002a000000-ffff88002a3fffff] pcifront pci-0: Creating PCI Frontend Bus 0000:00 pcifront pci-0: PCI host bridge to bus 0000:00 pci_bus 0000:00: root bus resource [io 0x0000-0xffff] pci_bus 0000:00: root bus resource [mem 0x00000000-0xfffffffff] pci 0000:00:00.0: [8086:10d3] type 00 class 0x020000 pci 0000:00:00.0: reg 10: [mem 0xfe5c0000-0xfe5dffff] pci 0000:00:00.0: reg 14: [mem 0xfe500000-0xfe57ffff] pci 0000:00:00.0: reg 18: [io 0xe000-0xe01f] pci 0000:00:00.0: reg 1c: [mem 0xfe5e0000-0xfe5e3fff] pcifront pci-0: claiming resource 0000:00:00.0/0 pcifront pci-0: claiming resource 0000:00:00.0/1 pcifront pci-0: claiming resource 0000:00:00.0/2 pcifront pci-0: claiming resource 0000:00:00.0/3 e1000e: Intel(R) PRO/1000 Network Driver - 2.0.0-k e1000e: Copyright(c) 1999 - 2012 Intel Corporation. e1000e 0000:00:00.0: Disabling ASPM L0s L1 e1000e 0000:00:00.0: enabling device (0000 -> 0002) e1000e 0000:00:00.0: Xen PCI mapped GSI16 to IRQ34 e1000e 0000:00:00.0: (unregistered net_device): Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode e1000e 0000:00:00.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:1b:21:ab:c6:13 e1000e 0000:00:00.0: eth0: Intel(R) PRO/1000 Network Connection e1000e 0000:00:00.0: eth0: MAC: 3, PHY: 8, PBA No: E46981-005 The "Warning only" will go away if one supplies 'iommu=soft' instead as we have a higher chance of being able to allocate large swaths of memory. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-31 10:26:59 +00:00
if (!err && !swiotlb_nr_tbl()) {
err = pci_xen_swiotlb_init_late();
if (err)
dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n");
}
return err;
}
static void pcifront_disconnect(struct pcifront_device *pdev)
{
spin_lock(&pcifront_dev_lock);
if (pdev == pcifront_dev) {
dev_info(&pdev->xdev->dev,
"Disconnecting PCI Frontend Buses\n");
pcifront_dev = NULL;
}
spin_unlock(&pcifront_dev_lock);
}
static struct pcifront_device *alloc_pdev(struct xenbus_device *xdev)
{
struct pcifront_device *pdev;
pdev = kzalloc(sizeof(struct pcifront_device), GFP_KERNEL);
if (pdev == NULL)
goto out;
pdev->sh_info =
(struct xen_pci_sharedinfo *)__get_free_page(GFP_KERNEL);
if (pdev->sh_info == NULL) {
kfree(pdev);
pdev = NULL;
goto out;
}
pdev->sh_info->flags = 0;
/*Flag for registering PV AER handler*/
set_bit(_XEN_PCIB_AERHANDLER, (void *)&pdev->sh_info->flags);
dev_set_drvdata(&xdev->dev, pdev);
pdev->xdev = xdev;
INIT_LIST_HEAD(&pdev->root_buses);
spin_lock_init(&pdev->sh_info_lock);
pdev->evtchn = INVALID_EVTCHN;
pdev->gnt_ref = INVALID_GRANT_REF;
pdev->irq = -1;
INIT_WORK(&pdev->op_work, pcifront_do_aer);
dev_dbg(&xdev->dev, "Allocated pdev @ 0x%p pdev->sh_info @ 0x%p\n",
pdev, pdev->sh_info);
out:
return pdev;
}
static void free_pdev(struct pcifront_device *pdev)
{
dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev);
pcifront_free_roots(pdev);
cancel_work_sync(&pdev->op_work);
if (pdev->irq >= 0)
unbind_from_irqhandler(pdev->irq, pdev);
if (pdev->evtchn != INVALID_EVTCHN)
xenbus_free_evtchn(pdev->xdev, pdev->evtchn);
if (pdev->gnt_ref != INVALID_GRANT_REF)
gnttab_end_foreign_access(pdev->gnt_ref, 0 /* r/w page */,
(unsigned long)pdev->sh_info);
else
free_page((unsigned long)pdev->sh_info);
dev_set_drvdata(&pdev->xdev->dev, NULL);
kfree(pdev);
}
static int pcifront_publish_info(struct pcifront_device *pdev)
{
int err = 0;
struct xenbus_transaction trans;
grant_ref_t gref;
err = xenbus_grant_ring(pdev->xdev, pdev->sh_info, 1, &gref);
if (err < 0)
goto out;
pdev->gnt_ref = gref;
err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn);
if (err)
goto out;
err = bind_evtchn_to_irqhandler(pdev->evtchn, pcifront_handler_aer,
0, "pcifront", pdev);
if (err < 0)
return err;
pdev->irq = err;
do_publish:
err = xenbus_transaction_start(&trans);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error writing configuration for backend "
"(start transaction)");
goto out;
}
err = xenbus_printf(trans, pdev->xdev->nodename,
"pci-op-ref", "%u", pdev->gnt_ref);
if (!err)
err = xenbus_printf(trans, pdev->xdev->nodename,
"event-channel", "%u", pdev->evtchn);
if (!err)
err = xenbus_printf(trans, pdev->xdev->nodename,
"magic", XEN_PCI_MAGIC);
if (err) {
xenbus_transaction_end(trans, 1);
xenbus_dev_fatal(pdev->xdev, err,
"Error writing configuration for backend");
goto out;
} else {
err = xenbus_transaction_end(trans, 0);
if (err == -EAGAIN)
goto do_publish;
else if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error completing transaction "
"for backend");
goto out;
}
}
xenbus_switch_state(pdev->xdev, XenbusStateInitialised);
dev_dbg(&pdev->xdev->dev, "publishing successful!\n");
out:
return err;
}
static int pcifront_try_connect(struct pcifront_device *pdev)
{
int err = -EFAULT;
int i, num_roots, len;
char str[64];
unsigned int domain, bus;
/* Only connect once */
if (xenbus_read_driver_state(pdev->xdev->nodename) !=
XenbusStateInitialised)
goto out;
xen/pcifront: Use Xen-SWIOTLB when initting if required. We piggyback on "xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used." functionality to start up the Xen-SWIOTLB if we are hot-plugged. This allows us to bypass the need to supply 'iommu=soft' on the Linux command line (mostly). With this patch, if a user forgot 'iommu=soft' on the command line, and hotplug a PCI device they will get: pcifront pci-0: Installing PCI frontend Warning: only able to allocate 4 MB for software IO TLB software IO TLB [mem 0x2a000000-0x2a3fffff] (4MB) mapped at [ffff88002a000000-ffff88002a3fffff] pcifront pci-0: Creating PCI Frontend Bus 0000:00 pcifront pci-0: PCI host bridge to bus 0000:00 pci_bus 0000:00: root bus resource [io 0x0000-0xffff] pci_bus 0000:00: root bus resource [mem 0x00000000-0xfffffffff] pci 0000:00:00.0: [8086:10d3] type 00 class 0x020000 pci 0000:00:00.0: reg 10: [mem 0xfe5c0000-0xfe5dffff] pci 0000:00:00.0: reg 14: [mem 0xfe500000-0xfe57ffff] pci 0000:00:00.0: reg 18: [io 0xe000-0xe01f] pci 0000:00:00.0: reg 1c: [mem 0xfe5e0000-0xfe5e3fff] pcifront pci-0: claiming resource 0000:00:00.0/0 pcifront pci-0: claiming resource 0000:00:00.0/1 pcifront pci-0: claiming resource 0000:00:00.0/2 pcifront pci-0: claiming resource 0000:00:00.0/3 e1000e: Intel(R) PRO/1000 Network Driver - 2.0.0-k e1000e: Copyright(c) 1999 - 2012 Intel Corporation. e1000e 0000:00:00.0: Disabling ASPM L0s L1 e1000e 0000:00:00.0: enabling device (0000 -> 0002) e1000e 0000:00:00.0: Xen PCI mapped GSI16 to IRQ34 e1000e 0000:00:00.0: (unregistered net_device): Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode e1000e 0000:00:00.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:1b:21:ab:c6:13 e1000e 0000:00:00.0: eth0: Intel(R) PRO/1000 Network Connection e1000e 0000:00:00.0: eth0: MAC: 3, PHY: 8, PBA No: E46981-005 The "Warning only" will go away if one supplies 'iommu=soft' instead as we have a higher chance of being able to allocate large swaths of memory. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-31 10:26:59 +00:00
err = pcifront_connect_and_init_dma(pdev);
xen/pcifront: Deal with toolstack missing 'XenbusStateClosing' state. There are two tool-stack that can instruct the Xen PCI frontend and backend to change states: 'xm' (Python code with a daemon), and 'xl' (C library - does not keep state changes). With the 'xm', the path to disconnect a single PCI device (xm pci-detach <guest> <BDF>) is: 4(Connected)->7(Reconfiguring*)-> 8(Reconfigured)-> 4(Connected)->5(Closing*). The * is for states that the tool-stack sets. For 'xl', it is similar: 4(Connected)->7(Reconfiguring*)-> 8(Reconfigured)-> 4(Connected) Both of them also tear down the XenBus structure, so the backend state ends up going in the 3(Initialised) and calls pcifront_xenbus_remove. When a PCI device is plugged back in (xm pci-attach <guest> <BDF>) both of them follow the same pattern: 2(InitWait*), 3(Initialized*), 4(Connected*)->4(Connected). [xen-pcifront ignores the 2,3 state changes and only acts when 4 (Connected) has been reached] Note that this is for a _single_ PCI device. If there were two PCI devices and only one was disconnected 'xm' would show the same state changes. The problem is that git commit 3d925320e9e2de162bd138bf97816bda8c3f71be ("xen/pcifront: Use Xen-SWIOTLB when initting if required") introduced a mechanism to initialize the SWIOTLB when the Xen PCI front moves to Connected state. It also had some aggressive seatbelt code check that would warn the user if one tried to change to Connected state without hitting first the Closing state: pcifront pci-0: PCI frontend already installed! However, that code can be relaxed and we can continue on working even if the frontend is instructed to be the 'Connected' state with no devices and then gets tickled to be in 'Connected' state again. In other words, this 4(Connected)->5(Closing)->4(Connected) state was expected, while 4(Connected)->.... anything but 5(Closing)->4(Connected) was not. This patch removes that aggressive check and allows Xen pcifront to work with the 'xl' toolstack (for one or more PCI devices) and with 'xm' toolstack (for more than two PCI devices). Acked-by: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-pci@vger.kernel.org Cc: stable@vger.kernel.org [v2: Added in the description about two PCI devices] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10 20:48:09 +00:00
if (err && err != -EEXIST) {
xenbus_dev_fatal(pdev->xdev, err,
xen/pcifront: Use Xen-SWIOTLB when initting if required. We piggyback on "xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used." functionality to start up the Xen-SWIOTLB if we are hot-plugged. This allows us to bypass the need to supply 'iommu=soft' on the Linux command line (mostly). With this patch, if a user forgot 'iommu=soft' on the command line, and hotplug a PCI device they will get: pcifront pci-0: Installing PCI frontend Warning: only able to allocate 4 MB for software IO TLB software IO TLB [mem 0x2a000000-0x2a3fffff] (4MB) mapped at [ffff88002a000000-ffff88002a3fffff] pcifront pci-0: Creating PCI Frontend Bus 0000:00 pcifront pci-0: PCI host bridge to bus 0000:00 pci_bus 0000:00: root bus resource [io 0x0000-0xffff] pci_bus 0000:00: root bus resource [mem 0x00000000-0xfffffffff] pci 0000:00:00.0: [8086:10d3] type 00 class 0x020000 pci 0000:00:00.0: reg 10: [mem 0xfe5c0000-0xfe5dffff] pci 0000:00:00.0: reg 14: [mem 0xfe500000-0xfe57ffff] pci 0000:00:00.0: reg 18: [io 0xe000-0xe01f] pci 0000:00:00.0: reg 1c: [mem 0xfe5e0000-0xfe5e3fff] pcifront pci-0: claiming resource 0000:00:00.0/0 pcifront pci-0: claiming resource 0000:00:00.0/1 pcifront pci-0: claiming resource 0000:00:00.0/2 pcifront pci-0: claiming resource 0000:00:00.0/3 e1000e: Intel(R) PRO/1000 Network Driver - 2.0.0-k e1000e: Copyright(c) 1999 - 2012 Intel Corporation. e1000e 0000:00:00.0: Disabling ASPM L0s L1 e1000e 0000:00:00.0: enabling device (0000 -> 0002) e1000e 0000:00:00.0: Xen PCI mapped GSI16 to IRQ34 e1000e 0000:00:00.0: (unregistered net_device): Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode e1000e 0000:00:00.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:1b:21:ab:c6:13 e1000e 0000:00:00.0: eth0: Intel(R) PRO/1000 Network Connection e1000e 0000:00:00.0: eth0: MAC: 3, PHY: 8, PBA No: E46981-005 The "Warning only" will go away if one supplies 'iommu=soft' instead as we have a higher chance of being able to allocate large swaths of memory. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-31 10:26:59 +00:00
"Error setting up PCI Frontend");
goto out;
}
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
"root_num", "%d", &num_roots);
if (err == -ENOENT) {
xenbus_dev_error(pdev->xdev, err,
"No PCI Roots found, trying 0000:00");
err = pcifront_scan_root(pdev, 0, 0);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root 0000:00");
goto out;
}
num_roots = 0;
} else if (err != 1) {
if (err == 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading number of PCI roots");
goto out;
}
for (i = 0; i < num_roots; i++) {
len = snprintf(str, sizeof(str), "root-%d", i);
if (unlikely(len >= (sizeof(str) - 1))) {
err = -ENOMEM;
goto out;
}
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
"%x:%x", &domain, &bus);
if (err != 2) {
if (err >= 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading PCI root %d", i);
goto out;
}
err = pcifront_scan_root(pdev, domain, bus);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root %04x:%02x",
domain, bus);
goto out;
}
}
err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
out:
return err;
}
static int pcifront_try_disconnect(struct pcifront_device *pdev)
{
int err = 0;
enum xenbus_state prev_state;
prev_state = xenbus_read_driver_state(pdev->xdev->nodename);
if (prev_state >= XenbusStateClosing)
goto out;
if (prev_state == XenbusStateConnected) {
pcifront_free_roots(pdev);
pcifront_disconnect(pdev);
}
err = xenbus_switch_state(pdev->xdev, XenbusStateClosed);
out:
return err;
}
static int pcifront_attach_devices(struct pcifront_device *pdev)
{
int err = -EFAULT;
int i, num_roots, len;
unsigned int domain, bus;
char str[64];
if (xenbus_read_driver_state(pdev->xdev->nodename) !=
XenbusStateReconfiguring)
goto out;
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
"root_num", "%d", &num_roots);
if (err == -ENOENT) {
xenbus_dev_error(pdev->xdev, err,
"No PCI Roots found, trying 0000:00");
err = pcifront_rescan_root(pdev, 0, 0);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root 0000:00");
goto out;
}
num_roots = 0;
} else if (err != 1) {
if (err == 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading number of PCI roots");
goto out;
}
for (i = 0; i < num_roots; i++) {
len = snprintf(str, sizeof(str), "root-%d", i);
if (unlikely(len >= (sizeof(str) - 1))) {
err = -ENOMEM;
goto out;
}
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
"%x:%x", &domain, &bus);
if (err != 2) {
if (err >= 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading PCI root %d", i);
goto out;
}
err = pcifront_rescan_root(pdev, domain, bus);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root %04x:%02x",
domain, bus);
goto out;
}
}
xenbus_switch_state(pdev->xdev, XenbusStateConnected);
out:
return err;
}
static int pcifront_detach_devices(struct pcifront_device *pdev)
{
int err = 0;
int i, num_devs;
unsigned int domain, bus, slot, func;
struct pci_dev *pci_dev;
char str[64];
if (xenbus_read_driver_state(pdev->xdev->nodename) !=
XenbusStateConnected)
goto out;
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d",
&num_devs);
if (err != 1) {
if (err >= 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading number of PCI devices");
goto out;
}
/* Find devices being detached and remove them. */
for (i = 0; i < num_devs; i++) {
int l, state;
l = snprintf(str, sizeof(str), "state-%d", i);
if (unlikely(l >= (sizeof(str) - 1))) {
err = -ENOMEM;
goto out;
}
state = xenbus_read_unsigned(pdev->xdev->otherend, str,
XenbusStateUnknown);
if (state != XenbusStateClosing)
continue;
/* Remove device. */
l = snprintf(str, sizeof(str), "vdev-%d", i);
if (unlikely(l >= (sizeof(str) - 1))) {
err = -ENOMEM;
goto out;
}
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
"%x:%x:%x.%x", &domain, &bus, &slot, &func);
if (err != 4) {
if (err >= 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading PCI device %d", i);
goto out;
}
pci_dev = pci_get_domain_bus_and_slot(domain, bus,
PCI_DEVFN(slot, func));
if (!pci_dev) {
dev_dbg(&pdev->xdev->dev,
"Cannot get PCI device %04x:%02x:%02x.%d\n",
domain, bus, slot, func);
continue;
}
pci_lock_rescan_remove();
pci_stop_and_remove_bus_device(pci_dev);
pci_dev_put(pci_dev);
pci_unlock_rescan_remove();
dev_dbg(&pdev->xdev->dev,
"PCI device %04x:%02x:%02x.%d removed.\n",
domain, bus, slot, func);
}
err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring);
out:
return err;
}
static void __ref pcifront_backend_changed(struct xenbus_device *xdev,
enum xenbus_state be_state)
{
struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
switch (be_state) {
case XenbusStateUnknown:
case XenbusStateInitialising:
case XenbusStateInitWait:
case XenbusStateInitialised:
break;
case XenbusStateConnected:
pcifront_try_connect(pdev);
break;
case XenbusStateClosed:
if (xdev->state == XenbusStateClosed)
break;
/* fall through - Missed the backend's CLOSING state. */
case XenbusStateClosing:
dev_warn(&xdev->dev, "backend going away!\n");
pcifront_try_disconnect(pdev);
break;
case XenbusStateReconfiguring:
pcifront_detach_devices(pdev);
break;
case XenbusStateReconfigured:
pcifront_attach_devices(pdev);
break;
}
}
static int pcifront_xenbus_probe(struct xenbus_device *xdev,
const struct xenbus_device_id *id)
{
int err = 0;
struct pcifront_device *pdev = alloc_pdev(xdev);
if (pdev == NULL) {
err = -ENOMEM;
xenbus_dev_fatal(xdev, err,
"Error allocating pcifront_device struct");
goto out;
}
err = pcifront_publish_info(pdev);
if (err)
free_pdev(pdev);
out:
return err;
}
static int pcifront_xenbus_remove(struct xenbus_device *xdev)
{
struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
if (pdev)
free_pdev(pdev);
return 0;
}
static const struct xenbus_device_id xenpci_ids[] = {
{"pci"},
{""},
};
static struct xenbus_driver xenpci_driver = {
.name = "pcifront",
.ids = xenpci_ids,
.probe = pcifront_xenbus_probe,
.remove = pcifront_xenbus_remove,
.otherend_changed = pcifront_backend_changed,
};
static int __init pcifront_init(void)
{
if (!xen_pv_domain() || xen_initial_domain())
return -ENODEV;
xen/pvhvm: If xen_platform_pci=0 is set don't blow up (v4). The user has the option of disabling the platform driver: 00:02.0 Unassigned class [ff80]: XenSource, Inc. Xen Platform Device (rev 01) which is used to unplug the emulated drivers (IDE, Realtek 8169, etc) and allow the PV drivers to take over. If the user wishes to disable that they can set: xen_platform_pci=0 (in the guest config file) or xen_emul_unplug=never (on the Linux command line) except it does not work properly. The PV drivers still try to load and since the Xen platform driver is not run - and it has not initialized the grant tables, most of the PV drivers stumble upon: input: Xen Virtual Keyboard as /devices/virtual/input/input5 input: Xen Virtual Pointer as /devices/virtual/input/input6M ------------[ cut here ]------------ kernel BUG at /home/konrad/ssd/konrad/linux/drivers/xen/grant-table.c:1206! invalid opcode: 0000 [#1] SMP Modules linked in: xen_kbdfront(+) xenfs xen_privcmd CPU: 6 PID: 1389 Comm: modprobe Not tainted 3.13.0-rc1upstream-00021-ga6c892b-dirty #1 Hardware name: Xen HVM domU, BIOS 4.4-unstable 11/26/2013 RIP: 0010:[<ffffffff813ddc40>] [<ffffffff813ddc40>] get_free_entries+0x2e0/0x300 Call Trace: [<ffffffff8150d9a3>] ? evdev_connect+0x1e3/0x240 [<ffffffff813ddd0e>] gnttab_grant_foreign_access+0x2e/0x70 [<ffffffffa0010081>] xenkbd_connect_backend+0x41/0x290 [xen_kbdfront] [<ffffffffa0010a12>] xenkbd_probe+0x2f2/0x324 [xen_kbdfront] [<ffffffff813e5757>] xenbus_dev_probe+0x77/0x130 [<ffffffff813e7217>] xenbus_frontend_dev_probe+0x47/0x50 [<ffffffff8145e9a9>] driver_probe_device+0x89/0x230 [<ffffffff8145ebeb>] __driver_attach+0x9b/0xa0 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230 [<ffffffff8145cf1c>] bus_for_each_dev+0x8c/0xb0 [<ffffffff8145e7d9>] driver_attach+0x19/0x20 [<ffffffff8145e260>] bus_add_driver+0x1a0/0x220 [<ffffffff8145f1ff>] driver_register+0x5f/0xf0 [<ffffffff813e55c5>] xenbus_register_driver_common+0x15/0x20 [<ffffffff813e76b3>] xenbus_register_frontend+0x23/0x40 [<ffffffffa0015000>] ? 0xffffffffa0014fff [<ffffffffa001502b>] xenkbd_init+0x2b/0x1000 [xen_kbdfront] [<ffffffff81002049>] do_one_initcall+0x49/0x170 .. snip.. which is hardly nice. This patch fixes this by having each PV driver check for: - if running in PV, then it is fine to execute (as that is their native environment). - if running in HVM, check if user wanted 'xen_emul_unplug=never', in which case bail out and don't load any PV drivers. - if running in HVM, and if PCI device 5853:0001 (xen_platform_pci) does not exist, then bail out and not load PV drivers. - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=ide-disks', then bail out for all PV devices _except_ the block one. Ditto for the network one ('nics'). - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=unnecessary' then load block PV driver, and also setup the legacy IDE paths. In (v3) make it actually load PV drivers. Reported-by: Sander Eikelenboom <linux@eikelenboom.it Reported-by: Anthony PERARD <anthony.perard@citrix.com> Reported-and-Tested-by: Fabio Fantoni <fabio.fantoni@m2r.biz> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v2: Add extra logic to handle the myrid ways 'xen_emul_unplug' can be used per Ian and Stefano suggestion] [v3: Make the unnecessary case work properly] [v4: s/disks/ide-disks/ spotted by Fabio] Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> [for PCI parts] CC: stable@vger.kernel.org
2013-11-26 20:05:40 +00:00
if (!xen_has_pv_devices())
return -ENODEV;
pci_frontend_registrar(1 /* enable */);
return xenbus_register_frontend(&xenpci_driver);
}
static void __exit pcifront_cleanup(void)
{
xenbus_unregister_driver(&xenpci_driver);
pci_frontend_registrar(0 /* disable */);
}
module_init(pcifront_init);
module_exit(pcifront_cleanup);
MODULE_DESCRIPTION("Xen PCI passthrough frontend.");
MODULE_LICENSE("GPL");
MODULE_ALIAS("xen:pci");