[PATCH] 9p: Use kvmalloc for message buffers

["Pierre Barre" <pierre@barre.sh>]

While developing a 9P server (https://github.com/Barre/ZeroFS) and testing it under high-load, I was running into allocation failures. The failures occur even with plenty of free memory available because kmalloc requires contiguous physical memory.

This results in errors like:
ls: page allocation failure: order:7, mode:0x40c40(GFP_NOFS|__GFP_COMP)

Signed-off-by: Pierre Barre <pierre@barre.sh>
---
 net/9p/client.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/9p/client.c b/net/9p/client.c
index 5c1ca57ccd28..f82b5674057c 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -230,7 +230,7 @@ static int p9_fcall_init(struct p9_client *c, struct p9_fcall *fc,
 		fc->sdata = kmem_cache_alloc(c->fcall_cache, GFP_NOFS);
 		fc->cache = c->fcall_cache;
 	} else {
-		fc->sdata = kmalloc(alloc_msize, GFP_NOFS);
+		fc->sdata = kvmalloc(alloc_msize, GFP_NOFS);
 		fc->cache = NULL;
 	}
 	if (!fc->sdata)
@@ -252,7 +252,7 @@ void p9_fcall_fini(struct p9_fcall *fc)
 	if (fc->cache)
 		kmem_cache_free(fc->cache, fc->sdata);
 	else
-		kfree(fc->sdata);
+		kvfree(fc->sdata);
 }
 EXPORT_SYMBOL(p9_fcall_fini);
 
-- 
2.39.5 (Apple Git-154)