From: Konrad Rzeszutek Wilk Date: Tue, 31 Jul 2012 10:26:59 +0000 (-0400) Subject: xen/pcifront: Use Xen-SWIOTLB when initting if required. X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=3d925320e9e2de162bd138bf97816bda8c3f71be;p=linux-beck.git 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 Signed-off-by: Konrad Rzeszutek Wilk --- diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index d6cc62cb4cf7..0ad8ca326389 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -21,6 +21,7 @@ #include #include +#include #define INVALID_GRANT_REF (0) #define INVALID_EVTCHN (-1) @@ -668,7 +669,7 @@ static irqreturn_t pcifront_handler_aer(int irq, void *dev) schedule_pcifront_aer_op(pdev); return IRQ_HANDLED; } -static int pcifront_connect(struct pcifront_device *pdev) +static int pcifront_connect_and_init_dma(struct pcifront_device *pdev) { int err = 0; @@ -681,9 +682,13 @@ static int pcifront_connect(struct pcifront_device *pdev) dev_err(&pdev->xdev->dev, "PCI frontend already installed!\n"); err = -EEXIST; } - spin_unlock(&pcifront_dev_lock); + 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; } @@ -842,10 +847,10 @@ static int __devinit pcifront_try_connect(struct pcifront_device *pdev) XenbusStateInitialised) goto out; - err = pcifront_connect(pdev); + err = pcifront_connect_and_init_dma(pdev); if (err) { xenbus_dev_fatal(pdev->xdev, err, - "Error connecting PCI Frontend"); + "Error setting up PCI Frontend"); goto out; }