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Fix: Avoid closing the file after loading segments to be able to lazily load from file without opening, w/ G

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sBubshait
2024-11-29 14:32:55 +00:00
parent 801fd7d310
commit 92d0b68243
3 changed files with 34 additions and 27 deletions
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30
src/vm/page.c
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@@ -69,30 +69,34 @@ page_get (void *upage)
bool
page_load (struct page_entry *page, bool writable)
{
void *frame = frame_alloc (PAL_USER, page->upage, thread_current());
/* Allocate a frame for the page. If a frame allocation fails, then
frame_alloc should try to evict a page. If it is still NULL, the OS
panics as this should not happen if eviction is working correctly. */
void *frame = frame_alloc (PAL_USER, page->upage, thread_current ());
if (frame == NULL)
return false; // TODO: Try to evict a page instead.
PANIC ("Could not allocate a frame to load page into memory.");
/* Map the page to the frame. */
if (!install_page (page->upage, frame, writable))
{
frame_free (frame);
return false;
}
printf ("Hi! 3\n");
{
frame_free (frame);
return false;
}
/* Move the file pointer to the correct location in the file. Then, read the
data from the file into the frame. Checks that we were able to read the
expected number of bytes. */
file_seek (page->file, page->offset);
int read = -1;
if ((read = file_read (page->file, frame, page->read_bytes)) != (int) page->read_bytes)
if (file_read (page->file, frame, page->read_bytes) != (int) page->read_bytes)
{
printf ("%p, %p, %d %d\n", page->file, frame, read, page->offset);
frame_free (frame);
return false;
}
printf ("Hi! 4\n");
/* Zero out the remaining bytes in the frame. */
memset (frame + page->read_bytes, 0, page->zero_bytes);
/* Mark the page as loaded successfully. */
return true;
}