summaryrefslogtreecommitdiffstats
path: root/drivers/usb/host/fhci-sched.c
diff options
context:
space:
mode:
authorStefani Seibold <stefani@seibold.net>2009-12-21 14:37:26 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2009-12-22 14:17:55 -0800
commit45465487897a1c6d508b14b904dc5777f7ec7e04 (patch)
tree935c8dae68dc793ff2f795d57cf027531475cd53 /drivers/usb/host/fhci-sched.c
parent2ec91eec47f713e3d158ba5b28a24a85a2cf3650 (diff)
downloadop-kernel-dev-45465487897a1c6d508b14b904dc5777f7ec7e04.zip
op-kernel-dev-45465487897a1c6d508b14b904dc5777f7ec7e04.tar.gz
kfifo: move struct kfifo in place
This is a new generic kernel FIFO implementation. The current kernel fifo API is not very widely used, because it has to many constrains. Only 17 files in the current 2.6.31-rc5 used it. FIFO's are like list's a very basic thing and a kfifo API which handles the most use case would save a lot of development time and memory resources. I think this are the reasons why kfifo is not in use: - The API is to simple, important functions are missing - A fifo can be only allocated dynamically - There is a requirement of a spinlock whether you need it or not - There is no support for data records inside a fifo So I decided to extend the kfifo in a more generic way without blowing up the API to much. The new API has the following benefits: - Generic usage: For kernel internal use and/or device driver. - Provide an API for the most use case. - Slim API: The whole API provides 25 functions. - Linux style habit. - DECLARE_KFIFO, DEFINE_KFIFO and INIT_KFIFO Macros - Direct copy_to_user from the fifo and copy_from_user into the fifo. - The kfifo itself is an in place member of the using data structure, this save an indirection access and does not waste the kernel allocator. - Lockless access: if only one reader and one writer is active on the fifo, which is the common use case, no additional locking is necessary. - Remove spinlock - give the user the freedom of choice what kind of locking to use if one is required. - Ability to handle records. Three type of records are supported: - Variable length records between 0-255 bytes, with a record size field of 1 bytes. - Variable length records between 0-65535 bytes, with a record size field of 2 bytes. - Fixed size records, which no record size field. - Preserve memory resource. - Performance! - Easy to use! This patch: Since most users want to have the kfifo as part of another object, reorganize the code to allow including struct kfifo in another data structure. This requires changing the kfifo_alloc and kfifo_init prototypes so that we pass an existing kfifo pointer into them. This patch changes the implementation and all existing users. [akpm@linux-foundation.org: fix warning] Signed-off-by: Stefani Seibold <stefani@seibold.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/usb/host/fhci-sched.c')
-rw-r--r--drivers/usb/host/fhci-sched.c10
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/usb/host/fhci-sched.c b/drivers/usb/host/fhci-sched.c
index 00a2985..ff43747 100644
--- a/drivers/usb/host/fhci-sched.c
+++ b/drivers/usb/host/fhci-sched.c
@@ -37,7 +37,7 @@ static void recycle_frame(struct fhci_usb *usb, struct packet *pkt)
pkt->info = 0;
pkt->priv_data = NULL;
- cq_put(usb->ep0->empty_frame_Q, pkt);
+ cq_put(&usb->ep0->empty_frame_Q, pkt);
}
/* confirm submitted packet */
@@ -57,7 +57,7 @@ void fhci_transaction_confirm(struct fhci_usb *usb, struct packet *pkt)
if ((td->data + td->actual_len) && trans_len)
memcpy(td->data + td->actual_len, pkt->data,
trans_len);
- cq_put(usb->ep0->dummy_packets_Q, pkt->data);
+ cq_put(&usb->ep0->dummy_packets_Q, pkt->data);
}
recycle_frame(usb, pkt);
@@ -213,7 +213,7 @@ static int add_packet(struct fhci_usb *usb, struct ed *ed, struct td *td)
}
/* update frame object fields before transmitting */
- pkt = cq_get(usb->ep0->empty_frame_Q);
+ pkt = cq_get(&usb->ep0->empty_frame_Q);
if (!pkt) {
fhci_dbg(usb->fhci, "there is no empty frame\n");
return -1;
@@ -222,7 +222,7 @@ static int add_packet(struct fhci_usb *usb, struct ed *ed, struct td *td)
pkt->info = 0;
if (data == NULL) {
- data = cq_get(usb->ep0->dummy_packets_Q);
+ data = cq_get(&usb->ep0->dummy_packets_Q);
BUG_ON(!data);
pkt->info = PKT_DUMMY_PACKET;
}
@@ -246,7 +246,7 @@ static int add_packet(struct fhci_usb *usb, struct ed *ed, struct td *td)
list_del_init(&td->frame_lh);
td->status = USB_TD_OK;
if (pkt->info & PKT_DUMMY_PACKET)
- cq_put(usb->ep0->dummy_packets_Q, pkt->data);
+ cq_put(&usb->ep0->dummy_packets_Q, pkt->data);
recycle_frame(usb, pkt);
usb->actual_frame->total_bytes -= (len + PROTOCOL_OVERHEAD);
fhci_err(usb->fhci, "host transaction failed\n");
OpenPOWER on IntegriCloud