Subversion Repositories pcie_ds_dma

 
#include <linux/kernel.h>
#include <linux/version.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/ioport.h>
#include <linux/pci.h>
#include <linux/pagemap.h>
#include <linux/interrupt.h>
#include <linux/proc_fs.h>
#include <linux/sched.h>
 
#include <asm/io.h>
 
 
#include "pexmodule.h"
#include "memory.h"
 
//--------------------------------------------------------------------
 
int lock_pages( void *va, u32 size )
{
    struct page *start_page_addr = virt_to_page(va);
    int i = 0;
 
    for (i=0; i < (size >> PAGE_SHIFT); i++) {
        SetPageReserved(start_page_addr+i);
        //dbg_msg(dbg_trace, "%s(): page_addr[%d] = 0x%x\n", __FUNCTION__, i, (int)(start_page_addr+i));
    }
 
    return i;
}
 
//--------------------------------------------------------------------
 
int unlock_pages( void *va, u32 size )
{
    struct page *start_page_addr = virt_to_page(va);
    int i = 0;
 
    for (i=0; i < (size >> PAGE_SHIFT); i++) {
        ClearPageReserved(start_page_addr+i);
        //dbg_msg(dbg_trace, "%s(): page_addr[%d] = 0x%x\n", __FUNCTION__, i, (int)(start_page_addr+i));
    }
 
    return i;
}
 
//--------------------------------------------------------------------
 
int check_address( void *pMemUserAddr )
{
        size_t addr = (size_t)pMemUserAddr;
        size_t mask = (size_t)~PAGE_MASK;
 
        printk("%s()\n", __FUNCTION__);
 
        // адрес пользовательского буфера должен быть выровнен на страницу
        if(addr & mask) {
            printk("%s(): %p - Error! Address must be aling at PAGE_SIZE border\n", __FUNCTION__, pMemUserAddr );
            return 1;
        }
 
        return 0;
    }
 
//--------------------------------------------------------------------
 
int check_size( size_t userSize )
{
        printk("%s()\n", __FUNCTION__);
 
        // размер пользовательского буфера должен быть кратен размеру страницы
        if((userSize % PAGE_SIZE) != 0) {
            printk("%s(): Invalid user memory block size - 0x%lX.\n", __FUNCTION__, userSize);
            return 1;
        }
 
        return 0;
}
 
//--------------------------------------------------------------------
 
int lock_user_memory( SHARED_MEMORY_DESCRIPTION *MemDscr, void* userSpaceAddress, size_t userSpaceSize )
{
        int i = 0;
        int requested_page_count = 0;
        int allocated_page_count = 0;
 
        printk("%s()\n", __FUNCTION__);
 
        if(!MemDscr) {
            printk("%s(): Invalid memory descriptor.\n", __FUNCTION__);
            return -EINVAL;
        }
 
        requested_page_count = (userSpaceSize >> PAGE_SHIFT);
 
        MemDscr->LockedPages = (struct page**)kmalloc(requested_page_count*sizeof(struct page*), GFP_KERNEL);
        if(!MemDscr->LockedPages) {
            printk("%s(): Cant allocate memory for locked pages pointers.\n", __FUNCTION__);
            return -ENOMEM;
        }
 
        memset(MemDscr->LockedPages,0,requested_page_count*sizeof(struct page*));
 
        down_read(&current->mm->mmap_sem);
#if LINUX_VERSION_CODE < KERNEL_VERSION(4,5,0)
        allocated_page_count = get_user_pages(current,
                                          current->mm,
                                          (size_t)userSpaceAddress,
                                          requested_page_count,
                                          1,
                                          0,
                                          MemDscr->LockedPages,
                                          0);
#endif
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,5,0)) && (LINUX_VERSION_CODE < KERNEL_VERSION(4,9,0))
        allocated_page_count = get_user_pages((size_t)userSpaceAddress,
                                          requested_page_count,
                                          1,
                                          0,
                                          MemDscr->LockedPages,
                                          0);
#endif
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,9,0))
        allocated_page_count = get_user_pages((size_t)userSpaceAddress,
                                          requested_page_count,
                                          1,
                                          MemDscr->LockedPages,
                                          0);
#endif
 
        up_read(&current->mm->mmap_sem);
 
        // если все ok то result содержит число страниц в массиве struct page *pages
        if(MemDscr->PageCount <= 0) {
            printk("%s(): Error to lock memory pages.\n", __FUNCTION__);
            kfree(MemDscr->LockedPages);
            MemDscr->LockedPages = NULL;
            MemDscr->PageCount = 0;
            return -ENOMEM;
        }
 
        printk("%s(): MemDscr->PageCount = %ld\n", __FUNCTION__, MemDscr->PageCount);
        printk("%s(): MemDscr->LockedPages = %p\n", __FUNCTION__, MemDscr->LockedPages);
 
        for(i=0; i<MemDscr->PageCount; i++) {
 
            printk("%s(): LockedPages[%d] = %p\n", __FUNCTION__, i, MemDscr->LockedPages[i]);
            printk("%s(): PhysicalAddress = %p\n", __FUNCTION__, (void*)page_to_phys(MemDscr->LockedPages[i]));
 
            if(!PageReserved(MemDscr->LockedPages[i])) {
                SetPageReserved(MemDscr->LockedPages[i]);
            }
        }
 
        printk("%s(): Lock %ld memory pages\n", __FUNCTION__, MemDscr->PageCount);
 
        return 0;
}
 
//--------------------------------------------------------------------
 
int unlock_user_memory( SHARED_MEMORY_DESCRIPTION *MemDscr )
{
        int i = 0;
 
        printk("%s()\n", __FUNCTION__);
 
        if(!MemDscr) {
            printk("%s(): Invalid parameter MemDscr = %p\n", __FUNCTION__, MemDscr);
            return -EINVAL;
        }
 
        printk("%s(): MemDscr = %p\n", __FUNCTION__, MemDscr);
 
        if(MemDscr->LockedPages)
            printk("%s(): MemDscr->LockedPages = %p\n", __FUNCTION__, MemDscr->LockedPages);
 
        for(i=0; i<MemDscr->PageCount; i++) {
            if(MemDscr->LockedPages[i]) {
                ClearPageReserved(MemDscr->LockedPages[i]);
                //page_cache_release(MemDscr->LockedPages[i]);
                printk("%s(): Unlock page %p\n", __FUNCTION__, MemDscr->LockedPages[i]);
            }
        }
 
        if(MemDscr->LockedPages)
            kfree(MemDscr->LockedPages);
 
        return 0;
}
 
//--------------------------------------------------------------------
 
void* allocate_memory_block(struct pex_device *brd, size_t block_size, dma_addr_t *dma_addr)
{
    struct mem_t *m = NULL;
    void *cpu_addr = NULL;
    dma_addr_t dma_handle = {0};
    int locked = 0;
 
    spin_lock(&brd->m_MemListLock);
 
    m = (struct mem_t*)kzalloc(sizeof(struct mem_t), GFP_KERNEL);
    if(!m) {
        err_msg(err_trace, "%s(): Error allocate memory for mem_t descriptor\n", __FUNCTION__);
        goto do_exit;
    }
 
    cpu_addr = dma_alloc_coherent(&brd->m_pci->dev, block_size, &dma_handle, GFP_KERNEL);
    if(!cpu_addr) {
        err_msg(err_trace, "%s(): Error allocate physical memory block.\n", __FUNCTION__);
        goto do_free_mem;
    }
 
    *dma_addr = dma_handle;
    m->dma_handle = dma_handle;
    m->cpu_addr = cpu_addr;
    m->size = block_size;
 
    locked = lock_pages(m->cpu_addr, m->size);
 
    list_add_tail(&m->list, &brd->m_MemList);
 
    atomic_inc(&brd->m_MemListCount);
 
    dbg_msg(dbg_trace, "%s(): %d: PA = 0x%zx, VA = %p, SZ = 0x%zx, PAGES = %d\n",
            __FUNCTION__, atomic_read(&brd->m_MemListCount), (size_t)m->dma_handle, m->cpu_addr, m->size, locked );
 
    spin_unlock(&brd->m_MemListLock);
 
    return cpu_addr;
 
do_free_mem:
    kfree(m);
 
do_exit:
    spin_unlock(&brd->m_MemListLock);
 
    return NULL;
}
 
//--------------------------------------------------------------------
 
int free_memory_block(struct pex_device *brd, struct memory_block mb)
{
    struct list_head *pos, *n;
    struct mem_t *m = NULL;
    int unlocked = 0;
 
    spin_lock(&brd->m_MemListLock);
 
    list_for_each_safe(pos, n, &brd->m_MemList) {
 
        m = list_entry(pos, struct mem_t, list);
 
        if(m->dma_handle != mb.phys)
            continue;
 
        unlocked = unlock_pages(m->cpu_addr, m->size);
 
        dma_free_coherent(&brd->m_pci->dev, m->size, m->cpu_addr, m->dma_handle);
 
        dbg_msg(dbg_trace, "%s(): %d: PA = 0x%zx, VA = %p, SZ = 0x%zx, PAGES = %d\n",
                __FUNCTION__, atomic_read(&brd->m_MemListCount), (size_t)m->dma_handle, m->cpu_addr, m->size, unlocked );
 
        list_del(pos);
 
        atomic_dec(&brd->m_MemListCount);
 
        kfree(m);
    }
 
    spin_unlock(&brd->m_MemListLock);
 
    return 0;
}
 
//--------------------------------------------------------------------