2.4 compatibility crap

1 files changed, 91 insertions, 0 deletions

diff --git a/linux/drivers/media/dvb/dvb-core/compat.c b/linux/drivers/media/dvb/dvb-core/compat.c
new file mode 100644
index 000000000..af33c58b7
--- /dev/null
+++ b/linux/drivers/media/dvb/dvb-core/compat.c
@@ -0,0 +1,91 @@
+#include <linux/slab.h>
+#include "compat.h"
+
+/**
+ *  compatibility crap for old kernels. No guarantee for a working driver
+ *  even when everything compiles.
+ */
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,45)) || !CONFIG_VIDEO_DEV
+int generic_usercopy(struct inode *inode, struct file *file,
+	             unsigned int cmd, unsigned long arg,
+		     int (*func)(struct inode *inode, struct file *file,
+		     unsigned int cmd, void *arg))
+{
+        char    sbuf[128];
+        void    *mbuf = NULL;
+        void    *parg = NULL;
+        int     err  = -EINVAL;
+
+        /*  Copy arguments into temp kernel buffer  */
+        switch (_IOC_DIR(cmd)) {
+        case _IOC_NONE:
+                parg = (void *)arg;
+                break;
+        case _IOC_READ: /* some v4l ioctls are marked wrong ... */
+        case _IOC_WRITE:
+        case (_IOC_WRITE | _IOC_READ):
+                if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
+                        parg = sbuf;
+                } else {
+                        /* too big to allocate from stack */
+                        mbuf = kmalloc(_IOC_SIZE(cmd),GFP_KERNEL);
+                        if (NULL == mbuf)
+                                return -ENOMEM;
+                        parg = mbuf;
+                }
+
+                err = -EFAULT;
+                if (copy_from_user(parg, (void *)arg, _IOC_SIZE(cmd)))
+                        goto out;
+                break;
+        }
+
+        /* call driver */
+        if ((err = func(inode, file, cmd, parg)) == -ENOIOCTLCMD)
+                err = -EINVAL;
+
+        if (err < 0)
+                goto out;
+
+        /*  Copy results into user buffer  */
+        switch (_IOC_DIR(cmd))
+        {
+        case _IOC_READ:
+        case (_IOC_WRITE | _IOC_READ):
+                if (copy_to_user((void *)arg, parg, _IOC_SIZE(cmd)))
+                        err = -EFAULT;
+                break;
+        }
+
+out:
+        if (mbuf)
+                kfree(mbuf);
+
+        return err;
+}
+#endif
+
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,45))
+struct page * vmalloc_to_page(void *vmalloc_addr)
+{
+        unsigned long addr = (unsigned long) vmalloc_addr;
+        struct page *page = NULL;
+        pgd_t *pgd = pgd_offset_k(addr);
+        pmd_t *pmd;
+        pte_t *ptep, pte;
+
+        if (!pgd_none(*pgd)) {
+                pmd = pmd_offset(pgd, addr);
+                if (!pmd_none(*pmd)) {
+                        ptep = pte_offset(pmd, addr);
+                        pte = *ptep;
+                        if (pte_present(pte))
+                                page = pte_page(pte);
+                }
+        }
+        return page;
+}
+#endif
+