usb-mtp: Reallocate buffer in multiples of MTP_WRITE_BUF_SZ

This is a "pre-patch" to breaking up the write buffer for
MTP writes. Instead of allocating a mtp buffer equal to size
sent by the initiator, we start with a small size and reallocate
multiples (of that small size) as needed.

Signed-off-by: Bandan Das <bsd@redhat.com>
Message-id: 20190129131908.27924-2-bsd@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
Bandan Das 2019-01-29 08:19:06 -05:00 committed by Gerd Hoffmann
parent b4329d1a2a
commit 179fcf8a83
1 changed files with 13 additions and 14 deletions

View File

@ -25,6 +25,7 @@
#include "trace.h"
#include "hw/usb.h"
#include "desc.h"
#include "qemu/units.h"
/* ----------------------------------------------------------------------- */
@ -152,7 +153,6 @@ struct MTPData {
bool first;
/* Used for >4G file sizes */
bool pending;
uint64_t cached_length;
int fd;
};
@ -244,6 +244,7 @@ typedef struct {
#define MTP_MANUFACTURER "QEMU"
#define MTP_PRODUCT "QEMU filesharing"
#define MTP_WRITE_BUF_SZ (512 * KiB)
enum {
STR_MANUFACTURER = 1,
@ -1659,7 +1660,7 @@ static void usb_mtp_write_data(MTPState *s)
d->fd = mkdir(path, mask);
goto free;
}
if ((s->dataset.size != 0xFFFFFFFF) && (s->dataset.size < d->length)) {
if ((s->dataset.size != 0xFFFFFFFF) && (s->dataset.size != d->offset)) {
usb_mtp_queue_result(s, RES_STORE_FULL, d->trans,
0, 0, 0, 0);
goto done;
@ -1777,17 +1778,21 @@ static void usb_mtp_get_data(MTPState *s, mtp_container *container,
total_len = cpu_to_le32(container->length) - sizeof(mtp_container);
/* Length of data in this packet */
data_len -= sizeof(mtp_container);
usb_mtp_realloc(d, total_len);
d->length += total_len;
if (total_len < MTP_WRITE_BUF_SZ) {
usb_mtp_realloc(d, total_len);
d->length += total_len;
} else {
usb_mtp_realloc(d, MTP_WRITE_BUF_SZ - sizeof(mtp_container));
d->length += MTP_WRITE_BUF_SZ - sizeof(mtp_container);
}
d->offset = 0;
d->cached_length = total_len;
d->first = false;
d->pending = false;
}
if (d->pending) {
usb_mtp_realloc(d, d->cached_length);
d->length += d->cached_length;
usb_mtp_realloc(d, MTP_WRITE_BUF_SZ);
d->length += MTP_WRITE_BUF_SZ;
d->pending = false;
}
@ -1795,12 +1800,6 @@ static void usb_mtp_get_data(MTPState *s, mtp_container *container,
dlen = data_len;
} else {
dlen = d->length - d->offset;
/* Check for cached data for large files */
if ((s->dataset.size == 0xFFFFFFFF) && (dlen < p->iov.size)) {
usb_mtp_realloc(d, p->iov.size - dlen);
d->length += p->iov.size - dlen;
dlen = p->iov.size;
}
}
switch (d->code) {
@ -1822,7 +1821,7 @@ static void usb_mtp_get_data(MTPState *s, mtp_container *container,
d->offset += dlen;
if ((p->iov.size % 64) || !p->iov.size) {
assert((s->dataset.size == 0xFFFFFFFF) ||
(s->dataset.size == d->length));
(s->dataset.size == d->offset));
usb_mtp_write_data(s);
usb_mtp_data_free(s->data_out);