[RFC PATCH 08/12] PAT 64b: coherent mmap and sysfs bin ioctl

From: venkatesh . pallipadi
Date: Thu Dec 13 2007 - 19:06:17 EST


Forward port of coherent-mmap.patch and sysfs-bin-ioctl.patch to x86 tree.

TBD: Do we need the ioctl interface to sysfs or get the type attribute
through a different sysfs file. And then actually specify the attribute
while doing pci_mmap_page_range ;-)

And when this interface is in place, X server has to use this interface for WC
mapping.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx>
Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
---

Index: linux-2.6.24-rc4/fs/sysfs/bin.c
===================================================================
--- linux-2.6.24-rc4.orig/fs/sysfs/bin.c 2007-12-11 16:23:26.000000000 -0800
+++ linux-2.6.24-rc4/fs/sysfs/bin.c 2007-12-11 16:32:01.000000000 -0800
@@ -221,6 +221,19 @@
return 0;
}

+static int ioctl(struct inode *i, struct file *f, unsigned cmd,
+ unsigned long arg)
+{
+ struct sysfs_dirent *attr_sd = f->f_path.dentry->d_fsdata;
+ struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
+ struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
+
+ if (!attr->ioctl)
+ return -EINVAL;
+
+ return attr->ioctl(kobj, attr, cmd, arg);
+}
+
const struct file_operations bin_fops = {
.read = read,
.write = write,
@@ -228,6 +241,7 @@
.llseek = generic_file_llseek,
.open = open,
.release = release,
+ .ioctl = ioctl,
};

/**
Index: linux-2.6.24-rc4/include/linux/sysfs.h
===================================================================
--- linux-2.6.24-rc4.orig/include/linux/sysfs.h 2007-12-11 16:23:26.000000000 -0800
+++ linux-2.6.24-rc4/include/linux/sysfs.h 2007-12-11 16:29:07.000000000 -0800
@@ -69,6 +69,8 @@
char *, loff_t, size_t);
int (*mmap)(struct kobject *, struct bin_attribute *attr,
struct vm_area_struct *vma);
+ int (*ioctl)(struct kobject *, struct bin_attribute *attr,
+ unsigned cmd, unsigned long arg);
};

struct sysfs_ops {
Index: linux-2.6.24-rc4/drivers/pci/pci-sysfs.c
===================================================================
--- linux-2.6.24-rc4.orig/drivers/pci/pci-sysfs.c 2007-12-11 16:03:55.000000000 -0800
+++ linux-2.6.24-rc4/drivers/pci/pci-sysfs.c 2007-12-11 16:29:07.000000000 -0800
@@ -473,8 +473,56 @@
kfree(res_attr);
}
}
+
+#ifdef HAVE_PCI_COHERENT_MMAP
+ sysfs_remove_bin_file(&pdev->dev.kobj, pdev->coherent_attr);
+ kfree(pdev->coherent_attr);
+#endif
+}
+
+#ifdef HAVE_PCI_COHERENT_MMAP
+
+struct coh_mmap_data {
+ void *map;
+ struct device *dev;
+ dma_addr_t busadr;
+};
+
+void pci_coherent_mmap_close(struct vm_area_struct *vma)
+{
+ struct coh_mmap_data *cm = vma->vm_private_data;
+ dma_free_coherent(cm->dev, vma->vm_end - vma->vm_start, cm->map,
+ cm->busadr);
}

+static struct vm_operations_struct pci_coherent_vmops = {
+ .close = pci_coherent_mmap_close,
+};
+
+static int
+pci_mmap_coherent_mem(struct kobject *kobj, struct bin_attribute *attr,
+ struct vm_area_struct *vma)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct coh_mmap_data *cm = kmalloc(sizeof(struct coh_mmap_data),
+ GFP_KERNEL);
+ if (!cm)
+ return -ENOMEM;
+ cm->map = dma_alloc_coherent(dev, vma->vm_end - vma->vm_start,
+ &cm->busadr, GFP_KERNEL);
+ cm->dev = dev;
+ if (!cm->map) {
+ kfree(cm->map);
+ return -ENOMEM;
+ }
+ vma->vm_private_data = cm;
+ vma->vm_pgoff = cm->busadr >> PAGE_SHIFT;
+ vma->vm_ops = &pci_coherent_vmops;
+ return pci_mmap_page_range(pdev, vma, pci_mmap_coherent, 0);
+}
+#endif
+
/**
* pci_create_resource_files - create resource files in sysfs for @dev
* @dev: dev in question
@@ -692,6 +740,22 @@
kfree(pdev->rom_attr);
}
}
+#ifdef HAVE_PCI_COHERENT_MMAP
+ {
+ struct bin_attribute *a = kzalloc(sizeof(struct bin_attribute),
+ GFP_KERNEL);
+ if (!a)
+ return;
+ pdev->coherent_attr = a;
+ a->attr.name = "coherent_mem";
+ a->attr.mode = S_IRUSR | S_IWUSR;
+ a->attr.owner = THIS_MODULE;
+ a->size = *(pdev->dev.dma_mask);
+ a->mmap = pci_mmap_coherent_mem;
+ a->private = NULL;
+ sysfs_create_bin_file(&pdev->dev.kobj, a);
+ }
+#endif
}

static int __init pci_sysfs_init(void)
Index: linux-2.6.24-rc4/include/asm-x86/pci.h
===================================================================
--- linux-2.6.24-rc4.orig/include/asm-x86/pci.h 2007-12-11 16:03:55.000000000 -0800
+++ linux-2.6.24-rc4/include/asm-x86/pci.h 2007-12-11 16:29:07.000000000 -0800
@@ -61,6 +61,7 @@


#define HAVE_PCI_MMAP
+#define HAVE_PCI_COHERENT_MMAP
extern int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
enum pci_mmap_state mmap_state, int write_combine);

Index: linux-2.6.24-rc4/include/linux/pci.h
===================================================================
--- linux-2.6.24-rc4.orig/include/linux/pci.h 2007-12-11 16:03:55.000000000 -0800
+++ linux-2.6.24-rc4/include/linux/pci.h 2007-12-11 16:29:07.000000000 -0800
@@ -57,7 +57,8 @@
/* File state for mmap()s on /proc/bus/pci/X/Y */
enum pci_mmap_state {
pci_mmap_io,
- pci_mmap_mem
+ pci_mmap_mem,
+ pci_mmap_coherent
};

/* This defines the direction arg to the DMA mapping routines. */
@@ -201,6 +202,7 @@
struct bin_attribute *rom_attr; /* attribute descriptor for sysfs ROM entry */
int rom_attr_enabled; /* has display of the rom attribute been enabled? */
struct bin_attribute *res_attr[DEVICE_COUNT_RESOURCE]; /* sysfs file for resources */
+ struct bin_attribute *coherent_attr;
#ifdef CONFIG_PCI_MSI
struct list_head msi_list;
#endif

--
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/