diff options
| author | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2021-08-28 13:19:02 +0200 |
|---|---|---|
| committer | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2021-08-28 13:26:35 +0200 |
| commit | b1f537b5e058512a263036b74d3b755301adaf96 (patch) | |
| tree | affed955ed63f6418039130be91133d5cea55f88 | |
| parent | dbf96c4953a2acf193c7804f3853eddd92a66f65 (diff) | |
linux block: allow loading data up to 4GiB limit
Linux drivers are only limited by the DMA32 constraint, not by the directmap
constraint. But our segment order is currently set to
DMA < DMA32 < DIRECTMAP < HIGHMEM (since that is what we will have in 64bit
mode). In PAE mode this makes DMA32 limited to 800MiB. Ideally we'd have
DMA < DIRECTMAP < DMA32 < HIGHMEM but that'd make the memory code more
complex, and we are to remove the Linux drivers anyway. In the
meanwhile, In non-PAE mode we can just use HIGHMEM which is already
limited to 4GiB, that will do the work.
* linux/dev/glue/block.c (VM_PAGE_LINUX): New macro.
(device_read): Use VM_PAGE_LINUX instead of VM_PAGE_DMA32.
| -rw-r--r-- | linux/dev/glue/block.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/linux/dev/glue/block.c b/linux/dev/glue/block.c index 709a8572..6730c5ec 100644 --- a/linux/dev/glue/block.c +++ b/linux/dev/glue/block.c @@ -84,6 +84,13 @@ #include <linux/dev/glue/glue.h> +#ifdef PAE +#warning TODO: make DMA32 between DIRECTMAP and HIGHMEM +#define VM_PAGE_LINUX VM_PAGE_DMA32 +#else +#define VM_PAGE_LINUX VM_PAGE_HIGHMEM +#endif + /* This task queue is not used in Mach: just for fixing undefined symbols. */ DECLARE_TASK_QUEUE (tq_disk); @@ -1525,7 +1532,7 @@ device_read (void *d, ipc_port_t reply_port, /* Allocate and map pages. */ while (alloc_offset < trunc_page (offset) + len) { - while ((m = vm_page_grab (VM_PAGE_DMA32)) == 0) + while ((m = vm_page_grab (VM_PAGE_LINUX)) == 0) VM_PAGE_WAIT (0); assert (! m->active && ! m->inactive); m->busy = TRUE; |