// Clean up a file-server file descriptor.
// This function is called by fd_close.
static int
file_close(struct Fd *fd)
{
// Unmap any data mapped for the file,
// then tell the file server that we have closed the file
// (to free up its resources).
// LAB 5: Your code here.
void *va;
void *start;
void *end;
int r;
start=(void *)fd2data(fd);
end=(void *)(start + fd->fd_file.file.f_size);
for (va=(void *)fd2data(fd); va <= end; va+=PGSIZE)
if (va_is_dirty2(va))
if ((r = fsipc_dirty(fd->fd_file.id, (off_t) (va - start))) < 0)
return r;
if ((r = fsipc_close(fd->fd_file.id)) < 0)
return r;
funmap(fd, fd->fd_file.file.f_size, 0, 0);
return 0;
}
// Unmap any file pages that no longer represent valid file pages
// when the size of the file as mapped in our address space decreases.
// Harmlessly does nothing if newsize >= oldsize.
static int
funmap(struct Fd* fd, off_t oldsize, off_t newsize, bool dirty)
{
size_t i;
char *va;
int r, ret;
va = fd2data(fd);
// Check vpd to see if anything is mapped.
if (!(vpd[VPD(va)] & PTE_P))
return 0;
ret = 0;
for (i = ROUNDUP(newsize, PGSIZE); i < oldsize; i += PGSIZE)
if (vpt[VPN(va + i)] & PTE_P) {
if (dirty
&& (vpt[VPN(va + i)] & PTE_D)
&& (r = fsipc_dirty(fd->fd_file.id, i)) < 0)
ret = r;
sys_page_unmap(0, va + i);
}
return ret;
}
// Unmap any file pages that no longer represent valid file pages
// when the size of the file as mapped in our address space decreases.
// Harmlessly does nothing if newsize >= oldsize.
static int
funmap(struct Fd* fd, off_t oldsize, off_t newsize, bool dirty)
{
size_t i;
char *va;
int r, ret;
// For each page that needs to be unmapped, notify the server if
// the page is dirty and remove the page.
// Hint: Use vpt to check if a page need to be unmapped.
// LAB 5: Your code here.
ret = 0;
va = fd2data(fd);
for (i = ROUNDUP(newsize, PGSIZE); i < oldsize; i += PGSIZE)
if (vpt[VPN(va + i)] & PTE_P) {
if (dirty && (vpt[VPN(va)] & PTE_D)
&& (r = fsipc_dirty(fd->fd_file.id, i)) < 0)
ret = r;
sys_page_unmap(0, va + i);
}
return ret;
}
