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-rw-r--r--microkernel/mach/externalpagermechanism.mdwn15
1 files changed, 7 insertions, 8 deletions
diff --git a/microkernel/mach/externalpagermechanism.mdwn b/microkernel/mach/externalpagermechanism.mdwn
index 1ccab6c4..169745fb 100644
--- a/microkernel/mach/externalpagermechanism.mdwn
+++ b/microkernel/mach/externalpagermechanism.mdwn
@@ -20,6 +20,7 @@ mechanism serves to separate *managing memory* from *managing
content*. Mach does the former while user space tasks do the
latter.
+
# Introduction
In Mach, a task's [[Mach/AddressSpace]] consists of references
@@ -66,7 +67,6 @@ The following illustrates the basic idea:
> \________/ <----- \________/
> (B) memory_object
-
(A) The client sends an "open" rpc to the server.
(B) The server creates a memory object (i.e., a port receive right), adds
@@ -99,6 +99,7 @@ the object. Multiple memory managers are a reality that should be
dealt with gracefully: they are useful for network transparent
mappings etc.
+
# Resolving Page Faults
> (G) Client ________
@@ -122,16 +123,15 @@ mappings etc.
> ____________
> / Hardware \
-
(A) The client does a memory access and faults. The kernel catches
the fault and maps the address to the appropriate memory object. It
-then invokes the memory_object_request method on the associated
+then invokes the memory\_object\_request method on the associated
capability. (In addition to the page to supply, it also supplies the
control port so that the server can determine which kernel
sent the message.)
(B) The manager dequeues the message. On the Hurd, this is translated
-into a store_read: a function in the libstore library which is used to
+into a store\_read: a function in the libstore library which is used to
transparently manage block devices. The storeio server starts off as
a separate process, however, if the server has the appropriate
permission, the backing object can be contacted directly by the
@@ -152,15 +152,15 @@ its own address space at the same time.
(E) The storeio transfers the page to the server. The page is still
anonymous.
-(F) The manager does a memory_object_supply transferring the page to
+(F) The manager does a memory\_object\_supply transferring the page to
the kernel. Only now is the page not considered to be anonymous but
managed.
(G) The kernel caches the page, installs it in the client's virtual
address space and finally, resumes the client.
-# Paging Data Out
+# Paging Data Out
> Change manager Pager m_o_return store_write
> \ _________ (B) __(A)__ (C) ________ (D) _______
@@ -170,7 +170,6 @@ address space and finally, resumes the client.
> P |
> /
-
(A) The paging [[policy]] is implemented by Mach: servers just implement
the [[mechanism]].
@@ -186,4 +185,4 @@ fashion. The server is not required to send a response to the kernel.
(D) The manager then transfers the data to the storeio which
eventually sends it to disk. The device driver consumes the memory
-doing the equivalent of a vm_deallocate.
+doing the equivalent of a vm\_deallocate.