[PATCH] net/9p: Handle get_user_pages_fast return properly

From: M. Mohan Kumar
Date: Fri Apr 15 2011 - 04:29:43 EST


Use proper data type to handle get_user_pages_fast error condition. Also
do not treat EFAULT error as fatal.

Signed-off-by: M. Mohan Kumar <mohan@xxxxxxxxxx>
---
net/9p/client.c | 2 +-
net/9p/trans_common.c | 11 +++--------
2 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/net/9p/client.c b/net/9p/client.c
index 691a04a..1612142 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -614,7 +614,7 @@ p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)

err = c->trans_mod->request(c, req);
if (err < 0) {
- if (err != -ERESTARTSYS)
+ if (err != -ERESTARTSYS && err != -EFAULT)
c->status = Disconnected;
goto reterr;
}
diff --git a/net/9p/trans_common.c b/net/9p/trans_common.c
index 14265e8..f020da9 100644
--- a/net/9p/trans_common.c
+++ b/net/9p/trans_common.c
@@ -63,7 +63,7 @@ p9_payload_gup(struct p9_req_t *req, size_t *pdata_off, int *pdata_len,
int nr_pages, u8 rw)
{
uint32_t first_page_bytes = 0;
- uint32_t pdata_mapped_pages;
+ int32_t pdata_mapped_pages;
struct trans_rpage_info *rpinfo;

*pdata_off = (__force size_t)req->tc->pubuf & (PAGE_SIZE-1);
@@ -75,14 +75,9 @@ p9_payload_gup(struct p9_req_t *req, size_t *pdata_off, int *pdata_len,
rpinfo = req->tc->private;
pdata_mapped_pages = get_user_pages_fast((unsigned long)req->tc->pubuf,
nr_pages, rw, &rpinfo->rp_data[0]);
+ if (pdata_mapped_pages <= 0)
+ return pdata_mapped_pages;

- if (pdata_mapped_pages < 0) {
- printk(KERN_ERR "get_user_pages_fast failed:%d udata:%p"
- "nr_pages:%d\n", pdata_mapped_pages,
- req->tc->pubuf, nr_pages);
- pdata_mapped_pages = 0;
- return -EIO;
- }
rpinfo->rp_nr_pages = pdata_mapped_pages;
if (*pdata_off) {
*pdata_len = first_page_bytes;
--
1.7.4

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