leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

staging: gasket: page table: remove code for "no dma_ops"

Browse Source 
Remove code with TODOs on it for working around apparent problems
previously seen in a qemu environment where dma_ops was not set
correctly.  There is no user of this in the current code.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Todd Poynor 2018-07-27 22:21:59 -07:00 committed by Greg Kroah-Hartman
parent 14d7022977
commit 758c579ec6
3 changed files with 8 additions and 55 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/staging/gasket/gasket_core.c
View File

@ -916,7 +916,7 @@ static int gasket_enable_dev(
&gasket_dev->bar_data[
driver_desc->page_table_bar_index],
&driver_desc->page_table_configs[tbl_idx],
gasket_dev->dev, gasket_dev->pci_dev, true);
gasket_dev->dev, gasket_dev->pci_dev);
if (ret) {
dev_err(gasket_dev->dev,
"Couldn't init page table %d: %d\n",

58
drivers/staging/gasket/gasket_page_table.c
View File

@ -212,12 +212,6 @@ struct gasket_page_table {
* gasket_mmap function, so user_virt belongs in the driver anyhow.
*/
struct gasket_coherent_page_entry *coherent_pages;
/*
* Whether the page table uses arch specific dma_ops or
* whether the driver is supplying its own.
*/
bool dma_ops;
};
/* Mapping declarations */
@ -290,7 +284,7 @@ int gasket_page_table_init(
struct gasket_page_table **ppg_tbl,
const struct gasket_bar_data *bar_data,
const struct gasket_page_table_config *page_table_config,
struct device *device, struct pci_dev *pci_dev, bool has_dma_ops)
struct device *device, struct pci_dev *pci_dev)
{
ulong bytes;
struct gasket_page_table *pg_tbl;
@ -353,7 +347,6 @@ int gasket_page_table_init(
bar_data->virt_base[page_table_config->extended_reg]);
pg_tbl->device = device;
pg_tbl->pci_dev = pci_dev;
pg_tbl->dma_ops = has_dma_ops;
dev_dbg(device, "Page table initialized successfully\n");
@ -759,33 +752,6 @@ static int gasket_map_extended_pages(
return 0;
}
/*
* TODO: dma_map_page() is not plugged properly when running under qemu. i.e.
* dma_ops are not set properly, which causes the kernel to assert.
*
* This temporary hack allows the driver to work on qemu, but need to be fixed:
* - either manually set the dma_ops for the architecture (which incidentally
* can't be done in an out-of-tree module) - or get qemu to fill the device tree
* properly so as linux plug the proper dma_ops or so as the driver can detect
* that it is runnig on qemu
*/
static inline dma_addr_t _no_op_dma_map_page(
struct device *dev, struct page *page, size_t offset, size_t size,
enum dma_data_direction dir)
{
/*
* struct dma_map_ops *ops = get_dma_ops(dev);
* dma_addr_t addr;
*
* kmemcheck_mark_initialized(page_address(page) + offset, size);
* BUG_ON(!valid_dma_direction(dir));
* addr = ops->map_page(dev, page, offset, size, dir, NULL);
* debug_dma_map_page(dev, page, offset, size, dir, addr, false);
*/
return page_to_phys(page);
}
/*
* Get and map last level page table buffers.
* @pg_tbl: Gasket page table pointer.
@ -856,16 +822,9 @@ static int gasket_perform_mapping(
ptes[i].offset = offset;
/* Map the page into DMA space. */
if (pg_tbl->dma_ops) {
/* hook in to kernel map functions */
ptes[i].dma_addr = dma_map_page(pg_tbl->device,
page, 0, PAGE_SIZE, DMA_BIDIRECTIONAL);
} else {
ptes[i].dma_addr = _no_op_dma_map_page(
pg_tbl->device, page, 0, PAGE_SIZE,
DMA_BIDIRECTIONAL);
}
ptes[i].dma_addr =
dma_map_page(pg_tbl->device, page, 0, PAGE_SIZE,
DMA_BIDIRECTIONAL);
dev_dbg(pg_tbl->device,
"%s i %d pte %p pfn %p -> mapped %llx\n",
__func__, i, &ptes[i],
@ -1042,13 +1001,8 @@ static int gasket_alloc_extended_subtable(
}
/* Map the page into DMA space. */
if (pg_tbl->dma_ops) {
pte->dma_addr = dma_map_page(pg_tbl->device, pte->page, 0,
PAGE_SIZE, DMA_BIDIRECTIONAL);
} else {
pte->dma_addr = _no_op_dma_map_page(pg_tbl->device, pte->page,
0, PAGE_SIZE, DMA_BIDIRECTIONAL);
}
pte->dma_addr = dma_map_page(pg_tbl->device, pte->page, 0, PAGE_SIZE,
DMA_BIDIRECTIONAL);
/* Wait until the page is mapped. */
mb();

3
drivers/staging/gasket/gasket_page_table.h
View File

@ -37,7 +37,6 @@ struct gasket_page_table;
* translation table.
* @device: Device structure for the underlying device. Only used for logging.
* @pci_dev: PCI system descriptor for the underlying device.
* @bool has_dma_ops: Whether the page table uses arch specific dma_ops or
* whether the driver will supply its own.
*
* Description: Allocates and initializes data to track address translation -
@ -51,7 +50,7 @@ int gasket_page_table_init(
struct gasket_page_table **ppg_tbl,
const struct gasket_bar_data *bar_data,
const struct gasket_page_table_config *page_table_config,
struct device *device, struct pci_dev *pci_dev, bool dma_ops);
struct device *device, struct pci_dev *pci_dev);
/*
* Deallocate and cleanup page table data.