Commit 179fcf8a authored by Bandan Das's avatar Bandan Das Committed by Gerd Hoffmann
Browse files

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: default avatarBandan Das <bsd@redhat.com>
Message-id: 20190129131908.27924-2-bsd@redhat.com
Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
parent b4329d1a

hw/usb/dev-mtp.c

+13 −14
Original line number Diff line number Diff line
@@ -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);

        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);