Hank Janssen
2010-Dec-13 20:34 UTC
[PATCH 1/1] hv: Use only one receive buffer per channel and kmalloc on initialize
Correct issue with not checking kmalloc return value.
This fix now only uses one receive buffer for all hv_utils
channels, and will do only one kmalloc on init and will return
with a -ENOMEM if kmalloc fails on initialize.
Thanks to Evgeniy Polyakov <zbr at ioremap.net> for pointing this out.
And thanks to Jesper Juhl <jj at chaosbits.net> and Ky Srinivasan
<ksrinivasan at novell.com> for suggesting a better implementation of
my original patch.
Signed-off-by: Haiyang Zhang <haiyangz at microsoft.com>
Signed-off-by: Hank Janssen <hjanssen at microsoft.com>
Cc: Evgeniy Polyakov <zbr at ioremap.net>
Cc: Jesper Juhl <jj at chaosbits.net>
Cc: Ky Srinivasan <ksrinivasan at novell.com>
---
drivers/staging/hv/hv_utils.c | 84 +++++++++++++++++++++-------------------
1 files changed, 44 insertions(+), 40 deletions(-)
diff --git a/drivers/staging/hv/hv_utils.c b/drivers/staging/hv/hv_utils.c
index 53e1e29..e0ecc23 100644
--- a/drivers/staging/hv/hv_utils.c
+++ b/drivers/staging/hv/hv_utils.c
@@ -38,12 +38,14 @@
#include "vmbus_api.h"
#include "utils.h"
+static u8 *shut_txf_buf;
+static u8 *time_txf_buf;
+static u8 *hbeat_txf_buf;
static void shutdown_onchannelcallback(void *context)
{
struct vmbus_channel *channel = context;
- u8 *buf;
- u32 buflen, recvlen;
+ u32 recvlen;
u64 requestid;
u8 execute_shutdown = false;
@@ -52,24 +54,23 @@ static void shutdown_onchannelcallback(void *context)
struct icmsg_hdr *icmsghdrp;
struct icmsg_negotiate *negop = NULL;
- buflen = PAGE_SIZE;
- buf = kmalloc(buflen, GFP_ATOMIC);
-
- vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid);
+ vmbus_recvpacket(channel, shut_txf_buf,
+ PAGE_SIZE, &recvlen, &requestid);
if (recvlen > 0) {
DPRINT_DBG(VMBUS, "shutdown packet: len=%d, requestid=%lld",
recvlen, requestid);
- icmsghdrp = (struct icmsg_hdr *)&buf[
+ icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
sizeof(struct vmbuspipe_hdr)];
if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
- prep_negotiate_resp(icmsghdrp, negop, buf);
+ prep_negotiate_resp(icmsghdrp, negop, shut_txf_buf);
} else {
- shutdown_msg = (struct shutdown_msg_data *)&buf[
- sizeof(struct vmbuspipe_hdr) +
- sizeof(struct icmsg_hdr)];
+ shutdown_msg + (struct shutdown_msg_data *)&shut_txf_buf[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
switch (shutdown_msg->flags) {
case 0:
@@ -93,13 +94,11 @@ static void shutdown_onchannelcallback(void *context)
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE;
- vmbus_sendpacket(channel, buf,
+ vmbus_sendpacket(channel, shut_txf_buf,
recvlen, requestid,
VmbusPacketTypeDataInBand, 0);
}
- kfree(buf);
-
if (execute_shutdown == true)
orderly_poweroff(false);
}
@@ -150,28 +149,25 @@ static inline void adj_guesttime(u64 hosttime, u8 flags)
static void timesync_onchannelcallback(void *context)
{
struct vmbus_channel *channel = context;
- u8 *buf;
- u32 buflen, recvlen;
+ u32 recvlen;
u64 requestid;
struct icmsg_hdr *icmsghdrp;
struct ictimesync_data *timedatap;
- buflen = PAGE_SIZE;
- buf = kmalloc(buflen, GFP_ATOMIC);
-
- vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid);
+ vmbus_recvpacket(channel, time_txf_buf,
+ PAGE_SIZE, &recvlen, &requestid);
if (recvlen > 0) {
DPRINT_DBG(VMBUS, "timesync packet: recvlen=%d, requestid=%lld",
recvlen, requestid);
- icmsghdrp = (struct icmsg_hdr *)&buf[
+ icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
sizeof(struct vmbuspipe_hdr)];
if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
- prep_negotiate_resp(icmsghdrp, NULL, buf);
+ prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf);
} else {
- timedatap = (struct ictimesync_data *)&buf[
+ timedatap = (struct ictimesync_data *)&time_txf_buf[
sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
adj_guesttime(timedatap->parenttime, timedatap->flags);
@@ -180,12 +176,10 @@ static void timesync_onchannelcallback(void *context)
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE;
- vmbus_sendpacket(channel, buf,
+ vmbus_sendpacket(channel, time_txf_buf,
recvlen, requestid,
VmbusPacketTypeDataInBand, 0);
}
-
- kfree(buf);
}
/*
@@ -196,30 +190,28 @@ static void timesync_onchannelcallback(void *context)
static void heartbeat_onchannelcallback(void *context)
{
struct vmbus_channel *channel = context;
- u8 *buf;
- u32 buflen, recvlen;
+ u32 recvlen;
u64 requestid;
struct icmsg_hdr *icmsghdrp;
struct heartbeat_msg_data *heartbeat_msg;
- buflen = PAGE_SIZE;
- buf = kmalloc(buflen, GFP_ATOMIC);
-
- vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid);
+ vmbus_recvpacket(channel, hbeat_txf_buf,
+ PAGE_SIZE, &recvlen, &requestid);
if (recvlen > 0) {
DPRINT_DBG(VMBUS, "heartbeat packet: len=%d, requestid=%lld",
recvlen, requestid);
- icmsghdrp = (struct icmsg_hdr *)&buf[
+ icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
sizeof(struct vmbuspipe_hdr)];
if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
- prep_negotiate_resp(icmsghdrp, NULL, buf);
+ prep_negotiate_resp(icmsghdrp, NULL, hbeat_txf_buf);
} else {
- heartbeat_msg = (struct heartbeat_msg_data *)&buf[
- sizeof(struct vmbuspipe_hdr) +
- sizeof(struct icmsg_hdr)];
+ heartbeat_msg + (struct heartbeat_msg_data *)&hbeat_txf_buf[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
DPRINT_DBG(VMBUS, "heartbeat seq = %lld",
heartbeat_msg->seq_num);
@@ -230,12 +222,10 @@ static void heartbeat_onchannelcallback(void *context)
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE;
- vmbus_sendpacket(channel, buf,
+ vmbus_sendpacket(channel, hbeat_txf_buf,
recvlen, requestid,
VmbusPacketTypeDataInBand, 0);
}
-
- kfree(buf);
}
static const struct pci_device_id __initconst
@@ -268,6 +258,16 @@ static int __init init_hyperv_utils(void)
if (!dmi_check_system(hv_utils_dmi_table))
return -ENODEV;
+ shut_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC);
+ time_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC);
+ hbeat_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC);
+
+ if (!shut_txf_buf || !time_txf_buf || !hbeat_txf_buf) {
+ printk(KERN_INFO
+ "Unable to allocate memory for receive buffer\n");
+ return -ENOMEM;
+ }
+
hv_cb_utils[HV_SHUTDOWN_MSG].channel->onchannel_callback
&shutdown_onchannelcallback;
hv_cb_utils[HV_SHUTDOWN_MSG].callback = &shutdown_onchannelcallback;
@@ -298,6 +298,10 @@ static void exit_hyperv_utils(void)
hv_cb_utils[HV_HEARTBEAT_MSG].channel->onchannel_callback
&chn_cb_negotiate;
hv_cb_utils[HV_HEARTBEAT_MSG].callback = &chn_cb_negotiate;
+
+ kfree(shut_txf_buf);
+ kfree(time_txf_buf);
+ kfree(hbeat_txf_buf);
}
module_init(init_hyperv_utils);
--
1.6.0.2
Jesper Juhl
2010-Dec-13 20:48 UTC
[PATCH 1/1] hv: Use only one receive buffer per channel and kmalloc on initialize
On Mon, 13 Dec 2010, Hank Janssen wrote:> Correct issue with not checking kmalloc return value. > This fix now only uses one receive buffer for all hv_utils > channels, and will do only one kmalloc on init and will return > with a -ENOMEM if kmalloc fails on initialize. > > Thanks to Evgeniy Polyakov <zbr at ioremap.net> for pointing this out. > And thanks to Jesper Juhl <jj at chaosbits.net> and Ky Srinivasan > <ksrinivasan at novell.com> for suggesting a better implementation of > my original patch. > > Signed-off-by: Haiyang Zhang <haiyangz at microsoft.com> > Signed-off-by: Hank Janssen <hjanssen at microsoft.com> > Cc: Evgeniy Polyakov <zbr at ioremap.net> > Cc: Jesper Juhl <jj at chaosbits.net> > Cc: Ky Srinivasan <ksrinivasan at novell.com> > > --- > drivers/staging/hv/hv_utils.c | 84 +++++++++++++++++++++------------------- > 1 files changed, 44 insertions(+), 40 deletions(-) > > diff --git a/drivers/staging/hv/hv_utils.c b/drivers/staging/hv/hv_utils.c > index 53e1e29..e0ecc23 100644 > --- a/drivers/staging/hv/hv_utils.c > +++ b/drivers/staging/hv/hv_utils.c > @@ -38,12 +38,14 @@ > #include "vmbus_api.h" > #include "utils.h" > > +static u8 *shut_txf_buf; > +static u8 *time_txf_buf; > +static u8 *hbeat_txf_buf; > > static void shutdown_onchannelcallback(void *context) > { > struct vmbus_channel *channel = context; > - u8 *buf; > - u32 buflen, recvlen; > + u32 recvlen; > u64 requestid; > u8 execute_shutdown = false; > > @@ -52,24 +54,23 @@ static void shutdown_onchannelcallback(void *context) > struct icmsg_hdr *icmsghdrp; > struct icmsg_negotiate *negop = NULL; > > - buflen = PAGE_SIZE; > - buf = kmalloc(buflen, GFP_ATOMIC); > - > - vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid); > + vmbus_recvpacket(channel, shut_txf_buf, > + PAGE_SIZE, &recvlen, &requestid); > > if (recvlen > 0) { > DPRINT_DBG(VMBUS, "shutdown packet: len=%d, requestid=%lld", > recvlen, requestid); > > - icmsghdrp = (struct icmsg_hdr *)&buf[ > + icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[ > sizeof(struct vmbuspipe_hdr)]; > > if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { > - prep_negotiate_resp(icmsghdrp, negop, buf); > + prep_negotiate_resp(icmsghdrp, negop, shut_txf_buf); > } else { > - shutdown_msg = (struct shutdown_msg_data *)&buf[ > - sizeof(struct vmbuspipe_hdr) + > - sizeof(struct icmsg_hdr)]; > + shutdown_msg > + (struct shutdown_msg_data *)&shut_txf_buf[ > + sizeof(struct vmbuspipe_hdr) + > + sizeof(struct icmsg_hdr)]; > > switch (shutdown_msg->flags) { > case 0: > @@ -93,13 +94,11 @@ static void shutdown_onchannelcallback(void *context) > icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION > | ICMSGHDRFLAG_RESPONSE; > > - vmbus_sendpacket(channel, buf, > + vmbus_sendpacket(channel, shut_txf_buf, > recvlen, requestid, > VmbusPacketTypeDataInBand, 0); > } > > - kfree(buf); > - > if (execute_shutdown == true) > orderly_poweroff(false); > } > @@ -150,28 +149,25 @@ static inline void adj_guesttime(u64 hosttime, u8 flags) > static void timesync_onchannelcallback(void *context) > { > struct vmbus_channel *channel = context; > - u8 *buf; > - u32 buflen, recvlen; > + u32 recvlen; > u64 requestid; > struct icmsg_hdr *icmsghdrp; > struct ictimesync_data *timedatap; > > - buflen = PAGE_SIZE; > - buf = kmalloc(buflen, GFP_ATOMIC); > - > - vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid); > + vmbus_recvpacket(channel, time_txf_buf, > + PAGE_SIZE, &recvlen, &requestid); > > if (recvlen > 0) { > DPRINT_DBG(VMBUS, "timesync packet: recvlen=%d, requestid=%lld", > recvlen, requestid); > > - icmsghdrp = (struct icmsg_hdr *)&buf[ > + icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[ > sizeof(struct vmbuspipe_hdr)]; > > if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { > - prep_negotiate_resp(icmsghdrp, NULL, buf); > + prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf); > } else { > - timedatap = (struct ictimesync_data *)&buf[ > + timedatap = (struct ictimesync_data *)&time_txf_buf[ > sizeof(struct vmbuspipe_hdr) + > sizeof(struct icmsg_hdr)]; > adj_guesttime(timedatap->parenttime, timedatap->flags); > @@ -180,12 +176,10 @@ static void timesync_onchannelcallback(void *context) > icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION > | ICMSGHDRFLAG_RESPONSE; > > - vmbus_sendpacket(channel, buf, > + vmbus_sendpacket(channel, time_txf_buf, > recvlen, requestid, > VmbusPacketTypeDataInBand, 0); > } > - > - kfree(buf); > } > > /* > @@ -196,30 +190,28 @@ static void timesync_onchannelcallback(void *context) > static void heartbeat_onchannelcallback(void *context) > { > struct vmbus_channel *channel = context; > - u8 *buf; > - u32 buflen, recvlen; > + u32 recvlen; > u64 requestid; > struct icmsg_hdr *icmsghdrp; > struct heartbeat_msg_data *heartbeat_msg; > > - buflen = PAGE_SIZE; > - buf = kmalloc(buflen, GFP_ATOMIC); > - > - vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid); > + vmbus_recvpacket(channel, hbeat_txf_buf, > + PAGE_SIZE, &recvlen, &requestid); > > if (recvlen > 0) { > DPRINT_DBG(VMBUS, "heartbeat packet: len=%d, requestid=%lld", > recvlen, requestid); > > - icmsghdrp = (struct icmsg_hdr *)&buf[ > + icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[ > sizeof(struct vmbuspipe_hdr)]; > > if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { > - prep_negotiate_resp(icmsghdrp, NULL, buf); > + prep_negotiate_resp(icmsghdrp, NULL, hbeat_txf_buf); > } else { > - heartbeat_msg = (struct heartbeat_msg_data *)&buf[ > - sizeof(struct vmbuspipe_hdr) + > - sizeof(struct icmsg_hdr)]; > + heartbeat_msg > + (struct heartbeat_msg_data *)&hbeat_txf_buf[ > + sizeof(struct vmbuspipe_hdr) + > + sizeof(struct icmsg_hdr)]; > > DPRINT_DBG(VMBUS, "heartbeat seq = %lld", > heartbeat_msg->seq_num); > @@ -230,12 +222,10 @@ static void heartbeat_onchannelcallback(void *context) > icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION > | ICMSGHDRFLAG_RESPONSE; > > - vmbus_sendpacket(channel, buf, > + vmbus_sendpacket(channel, hbeat_txf_buf, > recvlen, requestid, > VmbusPacketTypeDataInBand, 0); > } > - > - kfree(buf); > } > > static const struct pci_device_id __initconst > @@ -268,6 +258,16 @@ static int __init init_hyperv_utils(void) > if (!dmi_check_system(hv_utils_dmi_table)) > return -ENODEV; > > + shut_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC); > + time_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC); > + hbeat_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC); > + > + if (!shut_txf_buf || !time_txf_buf || !hbeat_txf_buf) { > + printk(KERN_INFO > + "Unable to allocate memory for receive buffer\n"); > + return -ENOMEM;You are leaking memory in the failure path. If for example one or two allocations succeed but one or two fail, then you'll leak the two successful allocations. I believe this should be if (!shut_txf_buf || !time_txf_buf || !hbeat_txf_buf) { printk(KERN_INFO "Unable to allocate memory for receive buffer\n"); kfree(hbeat_txf_buf); kfree(time_txf_buf); kfree(shut_txf_buf); return -ENOMEM; ...> + } > + > hv_cb_utils[HV_SHUTDOWN_MSG].channel->onchannel_callback > &shutdown_onchannelcallback; > hv_cb_utils[HV_SHUTDOWN_MSG].callback = &shutdown_onchannelcallback; > @@ -298,6 +298,10 @@ static void exit_hyperv_utils(void) > hv_cb_utils[HV_HEARTBEAT_MSG].channel->onchannel_callback > &chn_cb_negotiate; > hv_cb_utils[HV_HEARTBEAT_MSG].callback = &chn_cb_negotiate; > + > + kfree(shut_txf_buf); > + kfree(time_txf_buf); > + kfree(hbeat_txf_buf); > } > > module_init(init_hyperv_utils); >-- Jesper Juhl <jj at chaosbits.net> http://www.chaosbits.net/ Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please.
Ky Srinivasan
2010-Dec-13 22:05 UTC
[PATCH 1/1] hv: Use only one receive buffer per channel and kmalloc on initialize
>>> On 12/13/2010 at 3:34 PM, in message<1292272498-29483-1-git-send-email-hjanssen at microsoft.com>, Hank Janssen <hjanssen at microsoft.com> wrote:> Correct issue with not checking kmalloc return value. > This fix now only uses one receive buffer for all hv_utils > channels, and will do only one kmalloc on init and will return > with a -ENOMEM if kmalloc fails on initialize. > > Thanks to Evgeniy Polyakov <zbr at ioremap.net> for pointing this out. > And thanks to Jesper Juhl <jj at chaosbits.net> and Ky Srinivasan > <ksrinivasan at novell.com> for suggesting a better implementation of > my original patch. > > Signed-off-by: Haiyang Zhang <haiyangz at microsoft.com> > Signed-off-by: Hank Janssen <hjanssen at microsoft.com> > Cc: Evgeniy Polyakov <zbr at ioremap.net> > Cc: Jesper Juhl <jj at chaosbits.net> > Cc: Ky Srinivasan <ksrinivasan at novell.com> > > --- > drivers/staging/hv/hv_utils.c | 84 +++++++++++++++++++++------------------- > 1 files changed, 44 insertions(+), 40 deletions(-) > > diff --git a/drivers/staging/hv/hv_utils.c b/drivers/staging/hv/hv_utils.c > index 53e1e29..e0ecc23 100644 > --- a/drivers/staging/hv/hv_utils.c > +++ b/drivers/staging/hv/hv_utils.c > @@ -38,12 +38,14 @@ > #include "vmbus_api.h" > #include "utils.h" > > +static u8 *shut_txf_buf; > +static u8 *time_txf_buf; > +static u8 *hbeat_txf_buf; > > static void shutdown_onchannelcallback(void *context) > { > struct vmbus_channel *channel = context; > - u8 *buf; > - u32 buflen, recvlen; > + u32 recvlen; > u64 requestid; > u8 execute_shutdown = false; > > @@ -52,24 +54,23 @@ static void shutdown_onchannelcallback(void *context) > struct icmsg_hdr *icmsghdrp; > struct icmsg_negotiate *negop = NULL; > > - buflen = PAGE_SIZE; > - buf = kmalloc(buflen, GFP_ATOMIC); > - > - vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid); > + vmbus_recvpacket(channel, shut_txf_buf, > + PAGE_SIZE, &recvlen, &requestid); > > if (recvlen > 0) { > DPRINT_DBG(VMBUS, "shutdown packet: len=%d, requestid=%lld", > recvlen, requestid); > > - icmsghdrp = (struct icmsg_hdr *)&buf[ > + icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[ > sizeof(struct vmbuspipe_hdr)]; > > if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { > - prep_negotiate_resp(icmsghdrp, negop, buf); > + prep_negotiate_resp(icmsghdrp, negop, shut_txf_buf); > } else { > - shutdown_msg = (struct shutdown_msg_data *)&buf[ > - sizeof(struct vmbuspipe_hdr) + > - sizeof(struct icmsg_hdr)]; > + shutdown_msg > + (struct shutdown_msg_data *)&shut_txf_buf[ > + sizeof(struct vmbuspipe_hdr) + > + sizeof(struct icmsg_hdr)]; > > switch (shutdown_msg->flags) { > case 0: > @@ -93,13 +94,11 @@ static void shutdown_onchannelcallback(void *context) > icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION > | ICMSGHDRFLAG_RESPONSE; > > - vmbus_sendpacket(channel, buf, > + vmbus_sendpacket(channel, shut_txf_buf, > recvlen, requestid, > VmbusPacketTypeDataInBand, 0); > } > > - kfree(buf); > - > if (execute_shutdown == true) > orderly_poweroff(false); > } > @@ -150,28 +149,25 @@ static inline void adj_guesttime(u64 hosttime, u8 > flags) > static void timesync_onchannelcallback(void *context) > { > struct vmbus_channel *channel = context; > - u8 *buf; > - u32 buflen, recvlen; > + u32 recvlen; > u64 requestid; > struct icmsg_hdr *icmsghdrp; > struct ictimesync_data *timedatap; > > - buflen = PAGE_SIZE; > - buf = kmalloc(buflen, GFP_ATOMIC); > - > - vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid); > + vmbus_recvpacket(channel, time_txf_buf, > + PAGE_SIZE, &recvlen, &requestid); > > if (recvlen > 0) { > DPRINT_DBG(VMBUS, "timesync packet: recvlen=%d, requestid=%lld", > recvlen, requestid); > > - icmsghdrp = (struct icmsg_hdr *)&buf[ > + icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[ > sizeof(struct vmbuspipe_hdr)]; > > if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { > - prep_negotiate_resp(icmsghdrp, NULL, buf); > + prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf); > } else { > - timedatap = (struct ictimesync_data *)&buf[ > + timedatap = (struct ictimesync_data *)&time_txf_buf[ > sizeof(struct vmbuspipe_hdr) + > sizeof(struct icmsg_hdr)]; > adj_guesttime(timedatap->parenttime, timedatap->flags); > @@ -180,12 +176,10 @@ static void timesync_onchannelcallback(void *context) > icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION > | ICMSGHDRFLAG_RESPONSE; > > - vmbus_sendpacket(channel, buf, > + vmbus_sendpacket(channel, time_txf_buf, > recvlen, requestid, > VmbusPacketTypeDataInBand, 0); > } > - > - kfree(buf); > } > > /* > @@ -196,30 +190,28 @@ static void timesync_onchannelcallback(void *context) > static void heartbeat_onchannelcallback(void *context) > { > struct vmbus_channel *channel = context; > - u8 *buf; > - u32 buflen, recvlen; > + u32 recvlen; > u64 requestid; > struct icmsg_hdr *icmsghdrp; > struct heartbeat_msg_data *heartbeat_msg; > > - buflen = PAGE_SIZE; > - buf = kmalloc(buflen, GFP_ATOMIC); > - > - vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid); > + vmbus_recvpacket(channel, hbeat_txf_buf, > + PAGE_SIZE, &recvlen, &requestid); > > if (recvlen > 0) { > DPRINT_DBG(VMBUS, "heartbeat packet: len=%d, requestid=%lld", > recvlen, requestid); > > - icmsghdrp = (struct icmsg_hdr *)&buf[ > + icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[ > sizeof(struct vmbuspipe_hdr)]; > > if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { > - prep_negotiate_resp(icmsghdrp, NULL, buf); > + prep_negotiate_resp(icmsghdrp, NULL, hbeat_txf_buf); > } else { > - heartbeat_msg = (struct heartbeat_msg_data *)&buf[ > - sizeof(struct vmbuspipe_hdr) + > - sizeof(struct icmsg_hdr)]; > + heartbeat_msg > + (struct heartbeat_msg_data *)&hbeat_txf_buf[ > + sizeof(struct vmbuspipe_hdr) + > + sizeof(struct icmsg_hdr)]; > > DPRINT_DBG(VMBUS, "heartbeat seq = %lld", > heartbeat_msg->seq_num); > @@ -230,12 +222,10 @@ static void heartbeat_onchannelcallback(void *context) > icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION > | ICMSGHDRFLAG_RESPONSE; > > - vmbus_sendpacket(channel, buf, > + vmbus_sendpacket(channel, hbeat_txf_buf, > recvlen, requestid, > VmbusPacketTypeDataInBand, 0); > } > - > - kfree(buf); > } > > static const struct pci_device_id __initconst > @@ -268,6 +258,16 @@ static int __init init_hyperv_utils(void) > if (!dmi_check_system(hv_utils_dmi_table)) > return -ENODEV; > > + shut_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC); > + time_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC); > + hbeat_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC);Why are these allocations GFP_ATOMIC. Clearly this is in module loading context and you can afford to sleep. GFP_KERNEL should be fine. Regards, K. Y> + > + if (!shut_txf_buf || !time_txf_buf || !hbeat_txf_buf) { > + printk(KERN_INFO > + "Unable to allocate memory for receive buffer\n"); > + return -ENOMEM; > + } > + > hv_cb_utils[HV_SHUTDOWN_MSG].channel->onchannel_callback > &shutdown_onchannelcallback; > hv_cb_utils[HV_SHUTDOWN_MSG].callback = &shutdown_onchannelcallback; > @@ -298,6 +298,10 @@ static void exit_hyperv_utils(void) > hv_cb_utils[HV_HEARTBEAT_MSG].channel->onchannel_callback > &chn_cb_negotiate; > hv_cb_utils[HV_HEARTBEAT_MSG].callback = &chn_cb_negotiate; > + > + kfree(shut_txf_buf); > + kfree(time_txf_buf); > + kfree(hbeat_txf_buf); > } > > module_init(init_hyperv_utils);
Ky Srinivasan
2010-Dec-13 22:07 UTC
[PATCH 1/1] hv: Use only one receive buffer per channel and kmalloc on initialize
>>> On 12/13/2010 at 3:34 PM, in message<1292272498-29483-1-git-send-email-hjanssen at microsoft.com>, Hank Janssen <hjanssen at microsoft.com> wrote:> Correct issue with not checking kmalloc return value. > This fix now only uses one receive buffer for all hv_utils > channels, and will do only one kmalloc on init and will return > with a -ENOMEM if kmalloc fails on initialize. > > Thanks to Evgeniy Polyakov <zbr at ioremap.net> for pointing this out. > And thanks to Jesper Juhl <jj at chaosbits.net> and Ky Srinivasan > <ksrinivasan at novell.com> for suggesting a better implementation of > my original patch. > > Signed-off-by: Haiyang Zhang <haiyangz at microsoft.com> > Signed-off-by: Hank Janssen <hjanssen at microsoft.com> > Cc: Evgeniy Polyakov <zbr at ioremap.net> > Cc: Jesper Juhl <jj at chaosbits.net> > Cc: Ky Srinivasan <ksrinivasan at novell.com> > > --- > drivers/staging/hv/hv_utils.c | 84 +++++++++++++++++++++------------------- > 1 files changed, 44 insertions(+), 40 deletions(-) > > diff --git a/drivers/staging/hv/hv_utils.c b/drivers/staging/hv/hv_utils.c > index 53e1e29..e0ecc23 100644 > --- a/drivers/staging/hv/hv_utils.c > +++ b/drivers/staging/hv/hv_utils.c > @@ -38,12 +38,14 @@ > #include "vmbus_api.h" > #include "utils.h" > > +static u8 *shut_txf_buf; > +static u8 *time_txf_buf; > +static u8 *hbeat_txf_buf; > > static void shutdown_onchannelcallback(void *context) > { > struct vmbus_channel *channel = context; > - u8 *buf; > - u32 buflen, recvlen; > + u32 recvlen; > u64 requestid; > u8 execute_shutdown = false; > > @@ -52,24 +54,23 @@ static void shutdown_onchannelcallback(void *context) > struct icmsg_hdr *icmsghdrp; > struct icmsg_negotiate *negop = NULL; > > - buflen = PAGE_SIZE; > - buf = kmalloc(buflen, GFP_ATOMIC); > - > - vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid); > + vmbus_recvpacket(channel, shut_txf_buf, > + PAGE_SIZE, &recvlen, &requestid);Even if vmbus_recvpacket were to fail, why don't we just shut the guest down; after all we already know that is the intent of the host. Regards, K. Y> > if (recvlen > 0) { > DPRINT_DBG(VMBUS, "shutdown packet: len=%d, requestid=%lld", > recvlen, requestid); > > - icmsghdrp = (struct icmsg_hdr *)&buf[ > + icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[ > sizeof(struct vmbuspipe_hdr)]; > > if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { > - prep_negotiate_resp(icmsghdrp, negop, buf); > + prep_negotiate_resp(icmsghdrp, negop, shut_txf_buf); > } else { > - shutdown_msg = (struct shutdown_msg_data *)&buf[ > - sizeof(struct vmbuspipe_hdr) + > - sizeof(struct icmsg_hdr)]; > + shutdown_msg > + (struct shutdown_msg_data *)&shut_txf_buf[ > + sizeof(struct vmbuspipe_hdr) + > + sizeof(struct icmsg_hdr)]; > > switch (shutdown_msg->flags) { > case 0: > @@ -93,13 +94,11 @@ static void shutdown_onchannelcallback(void *context) > icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION > | ICMSGHDRFLAG_RESPONSE; > > - vmbus_sendpacket(channel, buf, > + vmbus_sendpacket(channel, shut_txf_buf, > recvlen, requestid, > VmbusPacketTypeDataInBand, 0); > } > > - kfree(buf); > - > if (execute_shutdown == true) > orderly_poweroff(false); > } > @@ -150,28 +149,25 @@ static inline void adj_guesttime(u64 hosttime, u8 > flags) > static void timesync_onchannelcallback(void *context) > { > struct vmbus_channel *channel = context; > - u8 *buf; > - u32 buflen, recvlen; > + u32 recvlen; > u64 requestid; > struct icmsg_hdr *icmsghdrp; > struct ictimesync_data *timedatap; > > - buflen = PAGE_SIZE; > - buf = kmalloc(buflen, GFP_ATOMIC); > - > - vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid); > + vmbus_recvpacket(channel, time_txf_buf, > + PAGE_SIZE, &recvlen, &requestid); > > if (recvlen > 0) { > DPRINT_DBG(VMBUS, "timesync packet: recvlen=%d, requestid=%lld", > recvlen, requestid); > > - icmsghdrp = (struct icmsg_hdr *)&buf[ > + icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[ > sizeof(struct vmbuspipe_hdr)]; > > if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { > - prep_negotiate_resp(icmsghdrp, NULL, buf); > + prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf); > } else { > - timedatap = (struct ictimesync_data *)&buf[ > + timedatap = (struct ictimesync_data *)&time_txf_buf[ > sizeof(struct vmbuspipe_hdr) + > sizeof(struct icmsg_hdr)]; > adj_guesttime(timedatap->parenttime, timedatap->flags); > @@ -180,12 +176,10 @@ static void timesync_onchannelcallback(void *context) > icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION > | ICMSGHDRFLAG_RESPONSE; > > - vmbus_sendpacket(channel, buf, > + vmbus_sendpacket(channel, time_txf_buf, > recvlen, requestid, > VmbusPacketTypeDataInBand, 0); > } > - > - kfree(buf); > } > > /* > @@ -196,30 +190,28 @@ static void timesync_onchannelcallback(void *context) > static void heartbeat_onchannelcallback(void *context) > { > struct vmbus_channel *channel = context; > - u8 *buf; > - u32 buflen, recvlen; > + u32 recvlen; > u64 requestid; > struct icmsg_hdr *icmsghdrp; > struct heartbeat_msg_data *heartbeat_msg; > > - buflen = PAGE_SIZE; > - buf = kmalloc(buflen, GFP_ATOMIC); > - > - vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid); > + vmbus_recvpacket(channel, hbeat_txf_buf, > + PAGE_SIZE, &recvlen, &requestid); > > if (recvlen > 0) { > DPRINT_DBG(VMBUS, "heartbeat packet: len=%d, requestid=%lld", > recvlen, requestid); > > - icmsghdrp = (struct icmsg_hdr *)&buf[ > + icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[ > sizeof(struct vmbuspipe_hdr)]; > > if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { > - prep_negotiate_resp(icmsghdrp, NULL, buf); > + prep_negotiate_resp(icmsghdrp, NULL, hbeat_txf_buf); > } else { > - heartbeat_msg = (struct heartbeat_msg_data *)&buf[ > - sizeof(struct vmbuspipe_hdr) + > - sizeof(struct icmsg_hdr)]; > + heartbeat_msg > + (struct heartbeat_msg_data *)&hbeat_txf_buf[ > + sizeof(struct vmbuspipe_hdr) + > + sizeof(struct icmsg_hdr)]; > > DPRINT_DBG(VMBUS, "heartbeat seq = %lld", > heartbeat_msg->seq_num); > @@ -230,12 +222,10 @@ static void heartbeat_onchannelcallback(void *context) > icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION > | ICMSGHDRFLAG_RESPONSE; > > - vmbus_sendpacket(channel, buf, > + vmbus_sendpacket(channel, hbeat_txf_buf, > recvlen, requestid, > VmbusPacketTypeDataInBand, 0); > } > - > - kfree(buf); > } > > static const struct pci_device_id __initconst > @@ -268,6 +258,16 @@ static int __init init_hyperv_utils(void) > if (!dmi_check_system(hv_utils_dmi_table)) > return -ENODEV; > > + shut_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC); > + time_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC); > + hbeat_txf_buf = kmalloc(PAGE_SIZE, GFP_ATOMIC); > + > + if (!shut_txf_buf || !time_txf_buf || !hbeat_txf_buf) { > + printk(KERN_INFO > + "Unable to allocate memory for receive buffer\n"); > + return -ENOMEM; > + } > + > hv_cb_utils[HV_SHUTDOWN_MSG].channel->onchannel_callback > &shutdown_onchannelcallback; > hv_cb_utils[HV_SHUTDOWN_MSG].callback = &shutdown_onchannelcallback; > @@ -298,6 +298,10 @@ static void exit_hyperv_utils(void) > hv_cb_utils[HV_HEARTBEAT_MSG].channel->onchannel_callback > &chn_cb_negotiate; > hv_cb_utils[HV_HEARTBEAT_MSG].callback = &chn_cb_negotiate; > + > + kfree(shut_txf_buf); > + kfree(time_txf_buf); > + kfree(hbeat_txf_buf); > } > > module_init(init_hyperv_utils);
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