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USB: g_mass_storage: constant length buffers used

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Using version of fsg_buffhd structure with buf field being an
array of characters with predefined size.  Since mass storage
function does not define changing buffer size on run-time it is
not required for the field to be a pointer to void and allocating
space dynamically.

Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Michal Nazarewicz 2009-10-28 16:57:21 +01:00 committed by Greg Kroah-Hartman
parent a41ae4180e
commit 606206c271
2 changed files with 21 additions and 20 deletions
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31
drivers/usb/gadget/f_mass_storage.c
View File

@ -258,6 +258,7 @@ static const char fsg_string_interface[] = "Mass Storage";
#define FSG_NO_INTR_EP 1
#define FSG_BUFFHD_STATIC_BUFFER 1
#include "storage_common.c"
@ -1894,9 +1895,8 @@ static int send_status(struct fsg_dev *fsg)
SK(sd), ASC(sd), ASCQ(sd), sdinfo);
}
/* Store and send the Bulk-only CSW */
csw = bh->buf;
csw = (void*)bh->buf;
csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
csw->Tag = fsg->tag;
@ -2808,10 +2808,6 @@ static void /* __init_or_exit */ fsg_unbind(struct usb_gadget *gadget)
complete(&fsg->thread_notifier);
}
/* Free the data buffers */
for (i = 0; i < FSG_NUM_BUFFERS; ++i)
kfree(fsg->common->buffhds[i].buf);
/* Free the request and buffer for endpoint 0 */
if (req) {
kfree(req->buf);
@ -2978,20 +2974,6 @@ static int __init fsg_bind(struct usb_gadget *gadget)
goto out;
req->complete = ep0_complete;
/* Allocate the data buffers */
for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
struct fsg_buffhd *bh = &fsg->common->buffhds[i];
/* Allocate for the bulk-in endpoint. We assume that
* the buffer will also work with the bulk-out (and
* interrupt-in) endpoint. */
bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
if (!bh->buf)
goto out;
bh->next = bh + 1;
}
fsg->common->buffhds[FSG_NUM_BUFFERS - 1].next = &fsg->common->buffhds[0];
/* This should reflect the actual gadget power source */
usb_gadget_set_selfpowered(gadget);
@ -3087,6 +3069,8 @@ static struct usb_gadget_driver fsg_driver = {
static int __init fsg_alloc(void)
{
struct fsg_dev *fsg;
struct fsg_buffhd *bh;
unsigned i;
fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
if (!fsg)
@ -3098,6 +3082,13 @@ static int __init fsg_alloc(void)
return -ENOMEM;
}
bh = fsg->common->buffhds;
i = FSG_NUM_BUFFERS - 1;
do {
bh->next = bh + 1;
} while (++bh, --i);
bh->next = fsg->common->buffhds;
spin_lock_init(&fsg->lock);
init_rwsem(&fsg->common->filesem);
init_completion(&fsg->thread_notifier);

10
drivers/usb/gadget/storage_common.c
View File

@ -47,6 +47,12 @@
* When FSG_NO_OTG is defined fsg_otg_desc won't be defined.
*/
/*
* When FSG_BUFFHD_STATIC_BUFFER is defined when this file is included
* the fsg_buffhd structure's buf field will be an array of FSG_BUFLEN
* characters rather then a pointer to void.
*/
#include <asm/unaligned.h>
@ -290,7 +296,11 @@ enum fsg_buffer_state {
};
struct fsg_buffhd {
#ifdef FSG_BUFFHD_STATIC_BUFFER
char buf[FSG_BUFLEN];
#else
void *buf;
#endif
enum fsg_buffer_state state;
struct fsg_buffhd *next;