diff options
| author | Ankit Jain <jankit@codeaurora.org> | 2019-02-04 07:45:43 +0300 |
|---|---|---|
| committer | Andy Gross <andy.gross@linaro.org> | 2019-03-28 07:32:25 +0300 |
| commit | 8da3daaa097171edd9658a82bbd3f335bc2e03ad (patch) | |
| tree | 2232ab6985a2c2ea1a52671772ae7dca4fd5f792 /drivers | |
| parent | 9e98c678c2d6ae3a17cb2de55d17f69dddaa231b (diff) | |
| download | linux-8da3daaa097171edd9658a82bbd3f335bc2e03ad.tar.xz | |
soc: qcom: rmtfs: Add support for mmap functionality
This change adds mmap functionality to rmtfs_mem driver.
Userspace application can map the address and use this
mapped address directly as buffer for read/write call to disk.
and avoid the read/write call to the shared path to copy the
buffer to userspace application.
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Ankit Jain <jankit@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/soc/qcom/rmtfs_mem.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/soc/qcom/rmtfs_mem.c b/drivers/soc/qcom/rmtfs_mem.c index 7200d762a951..6f5e8be9689c 100644 --- a/drivers/soc/qcom/rmtfs_mem.c +++ b/drivers/soc/qcom/rmtfs_mem.c @@ -137,6 +137,26 @@ static struct class rmtfs_class = { .name = "rmtfs", }; +static int qcom_rmtfs_mem_mmap(struct file *filep, struct vm_area_struct *vma) +{ + struct qcom_rmtfs_mem *rmtfs_mem = filep->private_data; + + if (vma->vm_end - vma->vm_start > rmtfs_mem->size) { + dev_dbg(&rmtfs_mem->dev, + "vm_end[%lu] - vm_start[%lu] [%lu] > mem->size[%pa]\n", + vma->vm_end, vma->vm_start, + (vma->vm_end - vma->vm_start), &rmtfs_mem->size); + return -EINVAL; + } + + vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot); + return remap_pfn_range(vma, + vma->vm_start, + rmtfs_mem->addr >> PAGE_SHIFT, + vma->vm_end - vma->vm_start, + vma->vm_page_prot); +} + static const struct file_operations qcom_rmtfs_mem_fops = { .owner = THIS_MODULE, .open = qcom_rmtfs_mem_open, @@ -144,6 +164,7 @@ static const struct file_operations qcom_rmtfs_mem_fops = { .write = qcom_rmtfs_mem_write, .release = qcom_rmtfs_mem_release, .llseek = default_llseek, + .mmap = qcom_rmtfs_mem_mmap, }; static void qcom_rmtfs_mem_release_device(struct device *dev) |