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path: root/drivers/scsi/st.c
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Diffstat (limited to 'drivers/scsi/st.c')
-rw-r--r--drivers/scsi/st.c78
1 files changed, 43 insertions, 35 deletions
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index ce1fd3ab243..1cfd217f890 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -3753,8 +3753,9 @@ static struct st_buffer *
else
priority = GFP_KERNEL;
- i = sizeof(struct st_buffer) + (max_sg - 1) * sizeof(struct scatterlist) +
- max_sg * sizeof(struct st_buf_fragment);
+ i = sizeof(struct st_buffer) +
+ (max_sg - 1) * sizeof(struct scatterlist);
+
tb = kzalloc(i, priority);
if (!tb) {
printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
@@ -3762,7 +3763,6 @@ static struct st_buffer *
}
tb->frp_segs = tb->orig_frp_segs = 0;
tb->use_sg = max_sg;
- tb->frp = (struct st_buf_fragment *)(&(tb->sg[0]) + max_sg);
tb->dma = need_dma;
tb->buffer_size = got;
@@ -3799,9 +3799,12 @@ static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dm
if (need_dma)
priority |= GFP_DMA;
+ if (STbuffer->cleared)
+ priority |= __GFP_ZERO;
+
if (STbuffer->frp_segs) {
- b_size = STbuffer->frp[0].length;
- order = get_order(b_size);
+ order = STbuffer->map_data.page_order;
+ b_size = PAGE_SIZE << order;
} else {
for (b_size = PAGE_SIZE, order = 0;
order <= 6 && b_size < new_size; order++, b_size *= 2)
@@ -3810,22 +3813,22 @@ static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dm
for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
segs < max_segs && got < new_size;) {
- STbuffer->frp[segs].page = alloc_pages(priority, order);
- if (STbuffer->frp[segs].page == NULL) {
+ struct page *page;
+
+ page = alloc_pages(priority, order);
+ if (!page) {
DEB(STbuffer->buffer_size = got);
normalize_buffer(STbuffer);
return 0;
}
- STbuffer->frp[segs].length = b_size;
+
STbuffer->frp_segs += 1;
got += b_size;
STbuffer->buffer_size = got;
- if (STbuffer->cleared)
- memset(page_address(STbuffer->frp[segs].page), 0, b_size);
- STbuffer->reserved_pages[segs] = STbuffer->frp[segs].page;
+ STbuffer->reserved_pages[segs] = page;
segs++;
}
- STbuffer->b_data = page_address(STbuffer->frp[0].page);
+ STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
STbuffer->map_data.page_order = order;
return 1;
@@ -3838,7 +3841,8 @@ static void clear_buffer(struct st_buffer * st_bp)
int i;
for (i=0; i < st_bp->frp_segs; i++)
- memset(page_address(st_bp->frp[i].page), 0, st_bp->frp[i].length);
+ memset(page_address(st_bp->reserved_pages[i]), 0,
+ PAGE_SIZE << st_bp->map_data.page_order);
st_bp->cleared = 1;
}
@@ -3846,12 +3850,11 @@ static void clear_buffer(struct st_buffer * st_bp)
/* Release the extra buffer */
static void normalize_buffer(struct st_buffer * STbuffer)
{
- int i, order;
+ int i, order = STbuffer->map_data.page_order;
for (i = STbuffer->orig_frp_segs; i < STbuffer->frp_segs; i++) {
- order = get_order(STbuffer->frp[i].length);
- __free_pages(STbuffer->frp[i].page, order);
- STbuffer->buffer_size -= STbuffer->frp[i].length;
+ __free_pages(STbuffer->reserved_pages[i], order);
+ STbuffer->buffer_size -= (PAGE_SIZE << order);
}
STbuffer->frp_segs = STbuffer->orig_frp_segs;
STbuffer->frp_sg_current = 0;
@@ -3866,18 +3869,19 @@ static void normalize_buffer(struct st_buffer * STbuffer)
static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
{
int i, cnt, res, offset;
+ int length = PAGE_SIZE << st_bp->map_data.page_order;
for (i = 0, offset = st_bp->buffer_bytes;
- i < st_bp->frp_segs && offset >= st_bp->frp[i].length; i++)
- offset -= st_bp->frp[i].length;
+ i < st_bp->frp_segs && offset >= length; i++)
+ offset -= length;
if (i == st_bp->frp_segs) { /* Should never happen */
printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
return (-EIO);
}
for (; i < st_bp->frp_segs && do_count > 0; i++) {
- cnt = st_bp->frp[i].length - offset < do_count ?
- st_bp->frp[i].length - offset : do_count;
- res = copy_from_user(page_address(st_bp->frp[i].page) + offset, ubp, cnt);
+ struct page *page = st_bp->reserved_pages[i];
+ cnt = length - offset < do_count ? length - offset : do_count;
+ res = copy_from_user(page_address(page) + offset, ubp, cnt);
if (res)
return (-EFAULT);
do_count -= cnt;
@@ -3897,18 +3901,19 @@ static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, in
static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
{
int i, cnt, res, offset;
+ int length = PAGE_SIZE << st_bp->map_data.page_order;
for (i = 0, offset = st_bp->read_pointer;
- i < st_bp->frp_segs && offset >= st_bp->frp[i].length; i++)
- offset -= st_bp->frp[i].length;
+ i < st_bp->frp_segs && offset >= length; i++)
+ offset -= length;
if (i == st_bp->frp_segs) { /* Should never happen */
printk(KERN_WARNING "st: from_buffer offset overflow.\n");
return (-EIO);
}
for (; i < st_bp->frp_segs && do_count > 0; i++) {
- cnt = st_bp->frp[i].length - offset < do_count ?
- st_bp->frp[i].length - offset : do_count;
- res = copy_to_user(ubp, page_address(st_bp->frp[i].page) + offset, cnt);
+ struct page *page = st_bp->reserved_pages[i];
+ cnt = length - offset < do_count ? length - offset : do_count;
+ res = copy_to_user(ubp, page_address(page) + offset, cnt);
if (res)
return (-EFAULT);
do_count -= cnt;
@@ -3929,6 +3934,7 @@ static void move_buffer_data(struct st_buffer * st_bp, int offset)
{
int src_seg, dst_seg, src_offset = 0, dst_offset;
int count, total;
+ int length = PAGE_SIZE << st_bp->map_data.page_order;
if (offset == 0)
return;
@@ -3936,24 +3942,26 @@ static void move_buffer_data(struct st_buffer * st_bp, int offset)
total=st_bp->buffer_bytes - offset;
for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
src_offset = offset;
- if (src_offset < st_bp->frp[src_seg].length)
+ if (src_offset < length)
break;
- offset -= st_bp->frp[src_seg].length;
+ offset -= length;
}
st_bp->buffer_bytes = st_bp->read_pointer = total;
for (dst_seg=dst_offset=0; total > 0; ) {
- count = min(st_bp->frp[dst_seg].length - dst_offset,
- st_bp->frp[src_seg].length - src_offset);
- memmove(page_address(st_bp->frp[dst_seg].page) + dst_offset,
- page_address(st_bp->frp[src_seg].page) + src_offset, count);
+ struct page *dpage = st_bp->reserved_pages[dst_seg];
+ struct page *spage = st_bp->reserved_pages[src_seg];
+
+ count = min(length - dst_offset, length - src_offset);
+ memmove(page_address(dpage) + dst_offset,
+ page_address(spage) + src_offset, count);
src_offset += count;
- if (src_offset >= st_bp->frp[src_seg].length) {
+ if (src_offset >= length) {
src_seg++;
src_offset = 0;
}
dst_offset += count;
- if (dst_offset >= st_bp->frp[dst_seg].length) {
+ if (dst_offset >= length) {
dst_seg++;
dst_offset = 0;
}