sambuc/codezero
1
0
Fork 0
mirror of https://github.com/drasko/codezero.git synced 2026-01-21 15:23:15 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity

Wiring between mm0 page cache and vfs almost what it should look like.

Browse Source 
This implements the infrastructure for read/write system calls where
file content is first searched in mm0's page cache and then read-in
or written via the vfs read/write functions.
	modified:   tasks/fs0/src/syscalls.c
	modified:   tasks/mm0/include/lib/bit.h
	modified:   tasks/mm0/include/lib/idpool.h
	modified:   tasks/mm0/include/task.h
	modified:   tasks/mm0/include/vm_area.h
	modified:   tasks/mm0/main.c
	modified:   tasks/mm0/src/devzero.c
	modified:   tasks/mm0/src/fault.c
	new file:   tasks/mm0/src/file.c
	modified:   tasks/mm0/src/init.c
	modified:   tasks/mm0/src/lib/bit.c
	modified:   tasks/mm0/src/lib/idpool.c
	modified:   tasks/mm0/src/task.c
This commit is contained in:
Bahadir Balban
2008-02-18 22:26:39 +00:00
parent 0fdc64ba2d
commit d67d6b84a9
13 changed files with 365 additions and 57 deletions
Download Patch File Download Diff File Expand all files Collapse all files

91
tasks/mm0/src/fault.c
View File

@@ -16,13 +16,25 @@
#include <string.h>
#include <memory.h>
#include <shm.h>
#include <file.h>
/* FIXME: TODO:
/* FIXME: FIXME: FIXME: FIXME: FIXME: FIXME: FIXME: FIXME: TODO:
* For every page that is allocated, (read-only file pages) and anon pages
* etc. Page cache for that page's file must be visited first, before
* allocation.
*/
unsigned long fault_to_file_offset(struct fault_data *fault)
{
/* Fault's offset in its vma */
unsigned long vma_off_pfn = __pfn(fault->address) - fault->vma->pfn_start;
/* Fault's offset in the file */
unsigned long f_off_pfn = fault->vma->f_offset + vma_off_pfn;
return f_off_pfn;
}
/*
* For copy-on-write vmas, grows an existing shadow vma, or creates a new one
* for the copy-on-write'ed page. Then adds this shadow vma to the actual vma's
@@ -87,6 +99,7 @@ int do_file_page(struct fault_data *fault)
void *paddr = alloc_page(1);
void *vaddr = phys_to_virt(paddr);
struct page *page = phys_to_page(paddr);
unsigned long f_offset = fault_to_file_offset(fault);
/* Map new page at a self virtual address temporarily */
l4_map(paddr, vaddr, 1, MAP_USR_RW_FLAGS, self_tid());
@@ -95,7 +108,8 @@ int do_file_page(struct fault_data *fault)
* Read the page. (Simply read into the faulty area that's
* now mapped using a newly allocated page.)
*/
fault->vma->owner->pager->ops.read_page(fault, vaddr);
fault->vma->owner->pager->ops.read_page(fault->vma->owner,
f_offset, vaddr);
/* Remove temporary mapping */
l4_unmap(vaddr, 1, self_tid());
@@ -191,6 +205,7 @@ int do_file_page(struct fault_data *fault)
void *paddr = alloc_page(1);
void *vaddr = phys_to_virt(paddr);
struct page *page = phys_to_page(paddr);
unsigned long f_offset = fault_to_file_offset(fault);
/* Map it to self */
l4_map(paddr, vaddr, 1, MAP_USR_RW_FLAGS, self_tid());
@@ -206,7 +221,8 @@ int do_file_page(struct fault_data *fault)
* Read the page. (Simply read into the faulty area that's
* now mapped using a newly allocated page.)
*/
fault->vma->owner->pager->ops.read_page(fault, vaddr);
fault->vma->owner->pager->ops.read_page(fault->vma->owner,
f_offset, vaddr);
/* Unmap from self */
l4_unmap(vaddr, 1, self_tid());
@@ -403,17 +419,43 @@ int do_page_fault(struct fault_data *fault)
return 0;
}
void vm_file_pager_read_page(struct fault_data *fault, void *dest_page)
int file_pager_read_page(struct vm_file *f, unsigned long f_offset, void *dest_page)
{
/* Fault's offset in its vma */
unsigned long vma_off_pfn = __pfn(fault->address) - fault->vma->pfn_start;
int err;
/* Fault's offset in the file */
unsigned long f_off_pfn = fault->vma->f_offset + vma_off_pfn;
/* Map the page to vfs task (shared mapping) */
l4_map(virt_to_phys(dest_page), dest_page, 1, MAP_USR_RW_FLAGS, VFS_TID);
/* vfs reads into the page. */
err = vfs_read(f->vnum, f_offset, 1, dest_page);
/* Unmap it from vfs */
l4_unmap(dest_page, 1, VFS_TID);
return err;
}
int file_pager_write_page(struct vm_file *f, unsigned long f_offset, void *src_page)
{
int err;
/* Map the page to vfs task (shared mapping) */
l4_map(virt_to_phys(src_page), src_page, 1, MAP_USR_RW_FLAGS, VFS_TID);
/* write the page via vfs. */
err = vfs_write(f->vnum, f_offset, 1, src_page);
/* Unmap it from vfs */
l4_unmap(src_page, 1, VFS_TID);
return err;
}
int boot_pager_read_page(struct vm_file *f, unsigned long f_off_pfn,
void *dest_page)
{
/* The address of page in the file */
void *file_page = (void *)(fault->vma->owner->inode.i_addr +
__pfn_to_addr(f_off_pfn));
void *file_page = (void *)(f->vnum + __pfn_to_addr(f_off_pfn));
/*
* Map the memfile's page into virtual memory.
@@ -425,37 +467,34 @@ void vm_file_pager_read_page(struct fault_data *fault, void *dest_page)
/* Copy it into destination page */
memcpy(dest_page, file_page, PAGE_SIZE);
return 0;
}
void vm_file_pager_write_page(struct fault_data *f, void *p)
{
}
void vm_swapper_read_page(struct fault_data *fault, void *p)
{
}
void vm_swapper_write_page(struct fault_data *f, void *p) { }
/* Pager for boot files read from sys_kdata() */
struct vm_pager boot_file_pager = {
.ops = {
.read_page = boot_pager_read_page,
.write_page= 0,
},
};
/* Pager for file pages */
struct vm_pager default_file_pager = {
.ops = {
.read_page = vm_file_pager_read_page,
.write_page= vm_file_pager_write_page,
.read_page = file_pager_read_page,
.write_page= 0,
},
};
/* Swap pager for anonymous and private pages */
struct vm_pager swap_pager = {
.ops = {
.read_page = vm_swapper_read_page,
.write_page= vm_swapper_write_page,
.read_page = 0,
.write_page= 0,
},
};
void page_fault_handler(l4id_t sender, fault_kdata_t *fkdata)
{
struct fault_data fault = {