** Sets up a transfer area - the functional part. Called by both
** ced_set_transfer and ced_set_circular.
****************************************************************************/
-static int ced_set_area(struct ced_data *ced, int nArea, char __user *puBuf,
- unsigned int dwLength, bool bCircular, bool bCircToHost)
+static int ced_set_area(struct ced_data *ced, int area, char __user *buf,
+ unsigned int length, bool circular, bool circ_to_host)
{
- /* Start by working out the page aligned start of the area and the size */
- /* of the area in pages, allowing for the start not being aligned and the */
- /* end needing to be rounded up to a page boundary. */
- unsigned long ulStart = ((unsigned long)puBuf) & PAGE_MASK;
- unsigned int ulOffset = ((unsigned long)puBuf) & (PAGE_SIZE - 1);
- int len = (dwLength + ulOffset + PAGE_SIZE - 1) >> PAGE_SHIFT;
-
- struct transarea *pTA = &ced->trans_def[nArea]; /* to save typing */
- struct page **pPages = NULL; /* space for page tables */
- int nPages = 0; /* and number of pages */
-
- int iReturn = ced_clear_area(ced, nArea); /* see if OK to use this area */
- if ((iReturn != U14ERR_NOTSET) && /* if not area unused and... */
- (iReturn != U14ERR_NOERROR)) /* ...not all OK, then... */
- return iReturn; /* ...we cannot use this area */
-
- if (!access_ok(VERIFY_WRITE, puBuf, dwLength)) /* if we cannot access the memory... */
+ /* Start by working out the page aligned start of the area and the */
+ /* size of the area in pages, allowing for the start not being */
+ /* aligned and the end needing to be rounded up to a page boundary. */
+ unsigned long start = ((unsigned long)buf) & PAGE_MASK;
+ unsigned int offset = ((unsigned long)buf) & (PAGE_SIZE - 1);
+ int len = (length + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
+
+ struct transarea *ta = &ced->trans_def[area]; /* to save typing */
+ struct page **pages = NULL; /* space for page tables */
+ int n_pages = 0; /* and number of pages */
+
+ int ret = ced_clear_area(ced, area); /* see if OK to use this area */
+ if ((ret != U14ERR_NOTSET) && /* if not area unused and... */
+ (ret != U14ERR_NOERROR)) /* ...not all OK, then... */
+ return ret; /* ...we cannot use this area */
+
+ /* if we cannot access the memory... */
+ if (!access_ok(VERIFY_WRITE, buf, length))
return -EFAULT; /* ...then we are done */
- /* Now allocate space to hold the page pointer and virtual address pointer tables */
- pPages = kmalloc(len * sizeof(struct page *), GFP_KERNEL);
- if (!pPages) {
- iReturn = U14ERR_NOMEMORY;
+ /* Now allocate space to hold the page pointer and */
+ /* virtual address pointer tables */
+ pages = kmalloc(len * sizeof(struct page *), GFP_KERNEL);
+ if (!pages) {
+ ret = U14ERR_NOMEMORY;
goto error;
}
dev_dbg(&ced->interface->dev, "%s: %p, length=%06x, circular %d\n",
- __func__, puBuf, dwLength, bCircular);
-
- /* To pin down user pages we must first acquire the mapping semaphore. */
- nPages = get_user_pages_fast(ulStart, len, 1, pPages);
- dev_dbg(&ced->interface->dev, "%s: nPages = %d\n", __func__, nPages);
-
- if (nPages > 0) { /* if we succeeded */
- /* If you are tempted to use page_address (form LDD3), forget it. You MUST use */
- /* kmap() or kmap_atomic() to get a virtual address. page_address will give you */
- /* (null) or at least it does in this context with an x86 machine. */
+ __func__, buf, length, circular);
+
+ /* To pin down user pages we must first */
+ /* acquire the mapping semaphore. */
+ n_pages = get_user_pages_fast(start, len, 1, pages);
+ dev_dbg(&ced->interface->dev, "%s: n_pages = %d\n", __func__, n_pages);
+
+ if (n_pages > 0) { /* if we succeeded */
+ /* If you are tempted to use page_address (form LDD3), forget */
+ /* it. You MUST use kmap() or kmap_atomic() to get a virtual */
+ /* address. page_address will give you (null) or at least it */
+ /* does in this context with an x86 machine. */
spin_lock_irq(&ced->staged_lock);
- pTA->buff = puBuf; /* keep start of region (user address) */
- pTA->base_offset = ulOffset; /* save offset in first page to start of xfer */
- pTA->length = dwLength; /* Size if the region in bytes */
- pTA->pages = pPages; /* list of pages that are used by buffer */
- pTA->n_pages = nPages; /* number of pages */
-
- pTA->circular = bCircular;
- pTA->circ_to_host = bCircToHost;
-
- pTA->blocks[0].offset = 0;
- pTA->blocks[0].size = 0;
- pTA->blocks[1].offset = 0;
- pTA->blocks[1].size = 0;
- pTA->used = true; /* This is now a used block */
+ ta->buff = buf; /* keep start of region (user address) */
+ ta->base_offset = offset; /* save offset in first page */
+ /* to start of xfer */
+ ta->length = length; /* Size if the region in bytes */
+ ta->pages = pages; /* list of pages that are used by buffer */
+ ta->n_pages = n_pages; /* number of pages */
+
+ ta->circular = circular;
+ ta->circ_to_host = circ_to_host;
+
+ ta->blocks[0].offset = 0;
+ ta->blocks[0].size = 0;
+ ta->blocks[1].offset = 0;
+ ta->blocks[1].size = 0;
+ ta->used = true; /* This is now a used block */
spin_unlock_irq(&ced->staged_lock);
- iReturn = U14ERR_NOERROR; /* say all was well */
+ ret = U14ERR_NOERROR; /* say all was well */
} else {
- iReturn = U14ERR_LOCKFAIL;
+ ret = U14ERR_LOCKFAIL;
goto error;
}
- return iReturn;
+ return ret;
error:
- kfree(pPages);
- return iReturn;
+ kfree(pages);
+ return ret;
}
/****************************************************************************
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