‫Hello, everybody, and in this lecture, we are just going to change some of the paging functionality,
‫if you go to paging Dr. Hajj, you will see Paging Switch accepts unit thirty two point paging said
‫unit thirty two point a paging map to unit thirty two point two and so on.
‫We're just going to change some of these to make it a bit cleaner.
‫So we're going to start with paging switch.
‫This should change to obstruct.
‫Paging four gigabyte chunk.
‫We now need to search for all instances of paging switch.
‫So we can see this one page in four gigabytes and get directory, just delete that.
‫Keep it simple.
‫Perfect.
‫So we can just have kind of chunk now, because now what we're essentially doing, where we're basically
‫saying that we want to pass in the paging fall by chunk rather than the unity ticket pointed to the
‫directory entry, because it's just easier to work with because then we don't have to do kind of chunk
‫directory entry.
‫Right, just to pass in the kernel check.
‫No problem.
‫So that's why we're doing this.
‫So that's the first.
‫Now impatient that see, we need to change this to struct paging four gigabyte chunk.
‫So here on line twenty nine, we're going to just access the directories directory entry like that.
‫OK, and again the current directory calls directory.
‫So we're going to go of directory equals directory directory entry like that you see.
‫So that's perfect.
‫So we've just perfected that function there.
‫And now if we go to task Stazi, we can also see that this problem exists here.
‫So we need to get rid of the directory entry by here because now we're just passing the page directory,
‫which is struct page him for gigabyte.
‫OK.
‫So, again, you know, the page switch to switch, it accesses the actual directory entry from the
‫paging forgiving about SHUNG provided to it.
‫OK, we've now refactored that function there.
‫OK, we'll keep paging set as it is, because it's quite a low level function.
‫It's debatable whether it should even be exported.
‫To be honest with you.
‫But we can keep it there, but we're not going to change anything here.
‫We will, however, change the paging map function by here.
‫We're going to go struct paging four gigabyte chunk, just as we did before.
‫And now let's search for Paging Max.
‫So we can see that one there.
‫So this is the sea far, so we're just going to go start paging four about SHUNG and that's the directory.
‫And by paging Sape, we're just going to go directory directory entry.
‫You see what I mean?
‫So we're just basically making the functions a bit more user friendly, a bit more programmer friendly.
‫So that one's now done.
‫Uh, let's go to the next one in here.
‫You can search by here.
‫Guys, this is the search bar here.
‫OK, so here we see paging map range.
‫We can come back to that one later.
‫Uh, we can see that the paging map range also uses the directory.
‫We don't need to change these guys because we're about to affect the paging map range to be exactly
‫the same.
‫So there's no need to access the directory entry here.
‫We can see paging map to again, we don't need to change that one.
‫It's completely fine.
‫The only one we need to worry about now is the process.
‫Start see.
‫OK, go to the post to start.
‫See here you can see paging map to and we go processed tasks, page directory directory entry just to
‫leave the directory entry.
‫But at the end.
‫OK.
‫Yep, that is perfect.
‫Excellent.
‫OK, so back to the page, and George had a file, we now have page a map to page a map range, so just
‫go we'll just put you page him map two to just go struct, paging four gigabyte chunk.
‫OK, and we're going to search for paging map, too, and we see this one in the C files.
‫So just change that one here, OK?
‫And we'll see page in map range and we pass the directory here.
‫We won't have to go directory directory entry here.
‫OK, guys, we are going to change that one to a page and four gigabyte chunk as well.
‫So no need to refactor that.
‫They're going to start C because we see something here and OK, we actually already did that earlier.
‫I mistook that for paging map.
‫So we actually already refactor this bit earlier because we literally about two minutes ago we changed
‫it from page directory directory entry suggests page directory.
‫So that's all fine.
‫Yet that one is perfected.
‫So back to the Hadifa.
‫We're going to go struct paging four gigabyte Schunk.
‫And this four map map range.
‫OK, I'm going to go to Page and Dot C, and now we see this one, OK, struct paging four gigabyte
‫chunk and that's directory.
‫And we now copy and paste the map range in here.
‫We can see that she is nowhere outside of this fall, so we've never factored that, guys, if we just
‫quickly do a make clean here and build that S.H..
‫We can see that compiles absolutely fine.
‫Everything runs as expected, perfect.
‫So, yeah, essentially what we did I'm going to just go over this in case any of you got lost.
‫We changed from the USA to T pointis here.
‫So the paging four gigabyte chunks.
‫We then searched for each function in the search bar here and we went through each one, changing them
‫until it compiles correctly.
‫OK, so that's what we did there.
‫Thank you for watching.