diff options
Diffstat (limited to 'drivers/lguest/core.c')
| -rw-r--r-- | drivers/lguest/core.c | 39 |
1 files changed, 8 insertions, 31 deletions
diff --git a/drivers/lguest/core.c b/drivers/lguest/core.c index 3aec29ec771..35d19ae58de 100644 --- a/drivers/lguest/core.c +++ b/drivers/lguest/core.c @@ -145,33 +145,10 @@ int lguest_address_ok(const struct lguest *lg, return (addr+len) / PAGE_SIZE < lg->pfn_limit && (addr+len >= addr); } -/* This is a convenient routine to get a 32-bit value from the Guest (a very - * common operation). Here we can see how useful the kill_lguest() routine we - * met in the Launcher can be: we return a random value (0) instead of needing - * to return an error. */ -u32 lgread_u32(struct lguest *lg, unsigned long addr) -{ - u32 val = 0; - - /* Don't let them access lguest binary. */ - if (!lguest_address_ok(lg, addr, sizeof(val)) - || get_user(val, (u32 *)(lg->mem_base + addr)) != 0) - kill_guest(lg, "bad read address %#lx: pfn_limit=%u membase=%p", addr, lg->pfn_limit, lg->mem_base); - return val; -} - -/* Same thing for writing a value. */ -void lgwrite_u32(struct lguest *lg, unsigned long addr, u32 val) -{ - if (!lguest_address_ok(lg, addr, sizeof(val)) - || put_user(val, (u32 *)(lg->mem_base + addr)) != 0) - kill_guest(lg, "bad write address %#lx", addr); -} - -/* This routine is more generic, and copies a range of Guest bytes into a - * buffer. If the copy_from_user() fails, we fill the buffer with zeroes, so - * the caller doesn't end up using uninitialized kernel memory. */ -void lgread(struct lguest *lg, void *b, unsigned long addr, unsigned bytes) +/* This routine copies memory from the Guest. Here we can see how useful the + * kill_lguest() routine we met in the Launcher can be: we return a random + * value (all zeroes) instead of needing to return an error. */ +void __lgread(struct lguest *lg, void *b, unsigned long addr, unsigned bytes) { if (!lguest_address_ok(lg, addr, bytes) || copy_from_user(b, lg->mem_base + addr, bytes) != 0) { @@ -181,15 +158,15 @@ void lgread(struct lguest *lg, void *b, unsigned long addr, unsigned bytes) } } -/* Similarly, our generic routine to copy into a range of Guest bytes. */ -void lgwrite(struct lguest *lg, unsigned long addr, const void *b, - unsigned bytes) +/* This is the write (copy into guest) version. */ +void __lgwrite(struct lguest *lg, unsigned long addr, const void *b, + unsigned bytes) { if (!lguest_address_ok(lg, addr, bytes) || copy_to_user(lg->mem_base + addr, b, bytes) != 0) kill_guest(lg, "bad write address %#lx len %u", addr, bytes); } -/* (end of memory access helper routines) :*/ +/*:*/ /*H:030 Let's jump straight to the the main loop which runs the Guest. * Remember, this is called by the Launcher reading /dev/lguest, and we keep |