shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-08 03:40:35 +09:00
Code Issues Packages Projects Releases Wiki Activity

ANDROID: goldfish_pipe: bugfixes and performance improvements.

Browse Source 
Combine following patches from android-goldfish-3.18 branch:

c0f015a [pipe] Fix the pipe driver for x64 platform + correct pages count
48e6bf5 [pipe] Use get_use_pages_fast() which is possibly faster
fb20f13 [goldfish] More pages in goldfish pipe
f180e6d goldfish_pipe: Return from read_write on signal and EIO
3dec3b7 [pipe] Fix a minor leak in setup_access_params_addr()

Change-Id: I1041fd65d7faaec123e6cedd3dbbc5a2fbb86c4d
This commit is contained in:
Yurii Zubrytskyi
2016-05-04 13:05:38 -07:00
committed by Dmitry Shmidt
parent 2bed6160b3
commit ba574b64bc
1 changed files with 72 additions and 38 deletions
Download Patch File Download Diff File Expand all files Collapse all files

110
drivers/platform/goldfish/goldfish_pipe.c
View File

@@ -110,6 +110,16 @@
#define PIPE_WAKE_READ (1 << 1) /* pipe can now be read from */
#define PIPE_WAKE_WRITE (1 << 2) /* pipe can now be written to */
#define MAX_PAGES_TO_GRAB 32
#define DEBUG 0
#if DEBUG
#define DPRINT(...) { printk(KERN_ERR __VA_ARGS__); }
#else
#define DPRINT(...)
#endif
struct access_params {
unsigned long channel;
u32 size;
@@ -231,8 +241,10 @@ static int setup_access_params_addr(struct platform_device *pdev,
if (valid_batchbuffer_addr(dev, aps)) {
dev->aps = aps;
return 0;
} else
} else {
devm_kfree(&pdev->dev, aps);
return -1;
}
}
/* A value that will not be set by qemu emulator */
@@ -269,6 +281,7 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
struct goldfish_pipe *pipe = filp->private_data;
struct goldfish_pipe_dev *dev = pipe->dev;
unsigned long address, address_end;
struct page* pages[MAX_PAGES_TO_GRAB] = {};
int count = 0, ret = -EINVAL;
/* If the emulator already closed the pipe, no need to go further */
@@ -293,45 +306,58 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
while (address < address_end) {
unsigned long page_end = (address & PAGE_MASK) + PAGE_SIZE;
unsigned long next = page_end < address_end ? page_end
: address_end;
unsigned long avail = next - address;
int status, wakeBit;
struct page *page;
/* Either vaddr or paddr depending on the device version */
unsigned long xaddr;
unsigned long next, avail;
int status, wakeBit, page_i, num_contiguous_pages;
long first_page, last_page, requested_pages;
unsigned long xaddr, xaddr_prev, xaddr_i;
/*
* We grab the pages on a page-by-page basis in case user
* space gives us a potentially huge buffer but the read only
* returns a small amount, then there's no need to pin that
* much memory to the process.
* Attempt to grab multiple physically contiguous pages.
*/
down_read(&current->mm->mmap_sem);
ret = get_user_pages(address, 1, is_write ? 0 : FOLL_WRITE,
&page, NULL);
up_read(&current->mm->mmap_sem);
if (ret < 0)
break;
if (dev->version) {
/* Device version 1 or newer (qemu-android) expects the
* physical address.
*/
xaddr = page_to_phys(page) | (address & ~PAGE_MASK);
} else {
/* Device version 0 (classic emulator) expects the
* virtual address.
*/
xaddr = address;
first_page = address & PAGE_MASK;
last_page = (address_end - 1) & PAGE_MASK;
requested_pages = ((last_page - first_page) >> PAGE_SHIFT) + 1;
if (requested_pages > MAX_PAGES_TO_GRAB) {
requested_pages = MAX_PAGES_TO_GRAB;
}
ret = get_user_pages_fast(first_page, requested_pages,
!is_write, pages);
DPRINT("%s: requested pages: %d %d\n", __FUNCTION__, ret, requested_pages);
if (ret == 0) {
DPRINT("%s: error: (requested pages == 0) (wanted %d)\n",
__FUNCTION__, requested_pages);
return ret;
}
if (ret < 0) {
DPRINT("%s: (requested pages < 0) %d \n",
__FUNCTION__, requested_pages);
return ret;
}
xaddr = page_to_phys(pages[0]) | (address & ~PAGE_MASK);
xaddr_prev = xaddr;
num_contiguous_pages = ret == 0 ? 0 : 1;
for (page_i = 1; page_i < ret; page_i++) {
xaddr_i = page_to_phys(pages[page_i]) | (address & ~PAGE_MASK);
if (xaddr_i == xaddr_prev + PAGE_SIZE) {
page_end += PAGE_SIZE;
xaddr_prev = xaddr_i;
num_contiguous_pages++;
} else {
DPRINT("%s: discontinuous page boundary: %d pages instead\n",
__FUNCTION__, page_i);
break;
}
}
next = page_end < address_end ? page_end : address_end;
avail = next - address;
/* Now, try to transfer the bytes in the current page */
spin_lock_irqsave(&dev->lock, irq_flags);
if (access_with_param(dev,
is_write ? CMD_WRITE_BUFFER : CMD_READ_BUFFER,
xaddr, avail, pipe, &status)) {
is_write ? CMD_WRITE_BUFFER : CMD_READ_BUFFER,
xaddr, avail, pipe, &status)) {
gf_write_ptr(pipe, dev->base + PIPE_REG_CHANNEL,
dev->base + PIPE_REG_CHANNEL_HIGH);
writel(avail, dev->base + PIPE_REG_SIZE);
@@ -344,9 +370,13 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
}
spin_unlock_irqrestore(&dev->lock, irq_flags);
if (status > 0 && !is_write)
set_page_dirty(page);
put_page(page);
for (page_i = 0; page_i < ret; page_i++) {
if (status > 0 && !is_write &&
page_i < num_contiguous_pages) {
set_page_dirty(pages[page_i]);
}
put_page(pages[page_i]);
}
if (status > 0) { /* Correct transfer */
count += status;
@@ -368,7 +398,7 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
*/
if (status != PIPE_ERROR_AGAIN)
pr_info_ratelimited("goldfish_pipe: backend returned error %d on %s\n",
status, is_write ? "write" : "read");
status, is_write ? "write" : "read");
ret = 0;
break;
}
@@ -378,7 +408,7 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
* non-blocking mode, just return the error code.
*/
if (status != PIPE_ERROR_AGAIN ||
(filp->f_flags & O_NONBLOCK) != 0) {
(filp->f_flags & O_NONBLOCK) != 0) {
ret = goldfish_pipe_error_convert(status);
break;
}
@@ -392,7 +422,7 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
/* Tell the emulator we're going to wait for a wake event */
goldfish_cmd(pipe,
is_write ? CMD_WAKE_ON_WRITE : CMD_WAKE_ON_READ);
is_write ? CMD_WAKE_ON_WRITE : CMD_WAKE_ON_READ);
/* Unlock the pipe, then wait for the wake signal */
mutex_unlock(&pipe->lock);
@@ -538,6 +568,8 @@ static int goldfish_pipe_open(struct inode *inode, struct file *file)
pipe->dev = dev;
mutex_init(&pipe->lock);
DPRINT("%s: call. pipe_dev pipe_dev=0x%lx new_pipe_addr=0x%lx file=0x%lx\n", __FUNCTION__, pipe_dev, pipe, file);
// spin lock init, write head of list, i guess
init_waitqueue_head(&pipe->wake_queue);
/*
@@ -560,6 +592,7 @@ static int goldfish_pipe_release(struct inode *inode, struct file *filp)
{
struct goldfish_pipe *pipe = filp->private_data;
DPRINT("%s: call. pipe=0x%lx file=0x%lx\n", __FUNCTION__, pipe, filp);
/* The guest is closing the channel, so tell the emulator right now */
goldfish_cmd(pipe, CMD_CLOSE);
kfree(pipe);
@@ -584,6 +617,7 @@ static struct miscdevice goldfish_pipe_device = {
static int goldfish_pipe_probe(struct platform_device *pdev)
{
DPRINT("%s: call. platform_device=0x%lx\n", __FUNCTION__, pdev);
int err;
struct resource *r;
struct goldfish_pipe_dev *dev = pipe_dev;