bio_init(bio);
if (likely(nr_iovecs)) {
- unsigned long idx = 0; /* shut up gcc */
+ unsigned long uninitialized_var(idx);
bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs);
if (unlikely(!bvl)) {
struct bio_map_data {
struct bio_vec *iovecs;
- void __user *userptr;
+ int nr_sgvecs;
+ struct sg_iovec *sgvecs;
};
-static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio)
+static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio,
+ struct sg_iovec *iov, int iov_count)
{
memcpy(bmd->iovecs, bio->bi_io_vec, sizeof(struct bio_vec) * bio->bi_vcnt);
+ memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count);
+ bmd->nr_sgvecs = iov_count;
bio->bi_private = bmd;
}
static void bio_free_map_data(struct bio_map_data *bmd)
{
kfree(bmd->iovecs);
+ kfree(bmd->sgvecs);
kfree(bmd);
}
-static struct bio_map_data *bio_alloc_map_data(int nr_segs)
+static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count)
{
struct bio_map_data *bmd = kmalloc(sizeof(*bmd), GFP_KERNEL);
return NULL;
bmd->iovecs = kmalloc(sizeof(struct bio_vec) * nr_segs, GFP_KERNEL);
- if (bmd->iovecs)
+ if (!bmd->iovecs) {
+ kfree(bmd);
+ return NULL;
+ }
+
+ bmd->sgvecs = kmalloc(sizeof(struct sg_iovec) * iov_count, GFP_KERNEL);
+ if (bmd->sgvecs)
return bmd;
+ kfree(bmd->iovecs);
kfree(bmd);
return NULL;
}
+static int __bio_copy_iov(struct bio *bio, struct sg_iovec *iov, int iov_count,
+ int uncopy)
+{
+ int ret = 0, i;
+ struct bio_vec *bvec;
+ int iov_idx = 0;
+ unsigned int iov_off = 0;
+ int read = bio_data_dir(bio) == READ;
+
+ __bio_for_each_segment(bvec, bio, i, 0) {
+ char *bv_addr = page_address(bvec->bv_page);
+ unsigned int bv_len = bvec->bv_len;
+
+ while (bv_len && iov_idx < iov_count) {
+ unsigned int bytes;
+ char *iov_addr;
+
+ bytes = min_t(unsigned int,
+ iov[iov_idx].iov_len - iov_off, bv_len);
+ iov_addr = iov[iov_idx].iov_base + iov_off;
+
+ if (!ret) {
+ if (!read && !uncopy)
+ ret = copy_from_user(bv_addr, iov_addr,
+ bytes);
+ if (read && uncopy)
+ ret = copy_to_user(iov_addr, bv_addr,
+ bytes);
+
+ if (ret)
+ ret = -EFAULT;
+ }
+
+ bv_len -= bytes;
+ bv_addr += bytes;
+ iov_addr += bytes;
+ iov_off += bytes;
+
+ if (iov[iov_idx].iov_len == iov_off) {
+ iov_idx++;
+ iov_off = 0;
+ }
+ }
+
+ if (uncopy)
+ __free_page(bvec->bv_page);
+ }
+
+ return ret;
+}
+
/**
* bio_uncopy_user - finish previously mapped bio
* @bio: bio being terminated
int bio_uncopy_user(struct bio *bio)
{
struct bio_map_data *bmd = bio->bi_private;
- const int read = bio_data_dir(bio) == READ;
- struct bio_vec *bvec;
- int i, ret = 0;
+ int ret;
- __bio_for_each_segment(bvec, bio, i, 0) {
- char *addr = page_address(bvec->bv_page);
- unsigned int len = bmd->iovecs[i].bv_len;
+ ret = __bio_copy_iov(bio, bmd->sgvecs, bmd->nr_sgvecs, 1);
- if (read && !ret && copy_to_user(bmd->userptr, addr, len))
- ret = -EFAULT;
-
- __free_page(bvec->bv_page);
- bmd->userptr += len;
- }
bio_free_map_data(bmd);
bio_put(bio);
return ret;
}
/**
- * bio_copy_user - copy user data to bio
+ * bio_copy_user_iov - copy user data to bio
* @q: destination block queue
- * @uaddr: start of user address
- * @len: length in bytes
+ * @iov: the iovec.
+ * @iov_count: number of elements in the iovec
* @write_to_vm: bool indicating writing to pages or not
*
* Prepares and returns a bio for indirect user io, bouncing data
* to/from kernel pages as necessary. Must be paired with
* call bio_uncopy_user() on io completion.
*/
-struct bio *bio_copy_user(struct request_queue *q, unsigned long uaddr,
- unsigned int len, int write_to_vm)
+struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov,
+ int iov_count, int write_to_vm)
{
- unsigned long end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
- unsigned long start = uaddr >> PAGE_SHIFT;
struct bio_map_data *bmd;
struct bio_vec *bvec;
struct page *page;
struct bio *bio;
int i, ret;
+ int nr_pages = 0;
+ unsigned int len = 0;
- bmd = bio_alloc_map_data(end - start);
+ for (i = 0; i < iov_count; i++) {
+ unsigned long uaddr;
+ unsigned long end;
+ unsigned long start;
+
+ uaddr = (unsigned long)iov[i].iov_base;
+ end = (uaddr + iov[i].iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ start = uaddr >> PAGE_SHIFT;
+
+ nr_pages += end - start;
+ len += iov[i].iov_len;
+ }
+
+ bmd = bio_alloc_map_data(nr_pages, iov_count);
if (!bmd)
return ERR_PTR(-ENOMEM);
- bmd->userptr = (void __user *) uaddr;
-
ret = -ENOMEM;
- bio = bio_alloc(GFP_KERNEL, end - start);
+ bio = bio_alloc(GFP_KERNEL, nr_pages);
if (!bio)
goto out_bmd;
* success
*/
if (!write_to_vm) {
- char __user *p = (char __user *) uaddr;
-
- /*
- * for a write, copy in data to kernel pages
- */
- ret = -EFAULT;
- bio_for_each_segment(bvec, bio, i) {
- char *addr = page_address(bvec->bv_page);
-
- if (copy_from_user(addr, p, bvec->bv_len))
- goto cleanup;
- p += bvec->bv_len;
- }
+ ret = __bio_copy_iov(bio, iov, iov_count, 0);
+ if (ret)
+ goto cleanup;
}
- bio_set_map_data(bmd, bio);
+ bio_set_map_data(bmd, bio, iov, iov_count);
return bio;
cleanup:
bio_for_each_segment(bvec, bio, i)
return ERR_PTR(ret);
}
+/**
+ * bio_copy_user - copy user data to bio
+ * @q: destination block queue
+ * @uaddr: start of user address
+ * @len: length in bytes
+ * @write_to_vm: bool indicating writing to pages or not
+ *
+ * Prepares and returns a bio for indirect user io, bouncing data
+ * to/from kernel pages as necessary. Must be paired with
+ * call bio_uncopy_user() on io completion.
+ */
+struct bio *bio_copy_user(struct request_queue *q, unsigned long uaddr,
+ unsigned int len, int write_to_vm)
+{
+ struct sg_iovec iov;
+
+ iov.iov_base = (void __user *)uaddr;
+ iov.iov_len = len;
+
+ return bio_copy_user_iov(q, &iov, 1, write_to_vm);
+}
+
static struct bio *__bio_map_user_iov(struct request_queue *q,
struct block_device *bdev,
struct sg_iovec *iov, int iov_count,
return ERR_PTR(-EINVAL);
}
+static void bio_copy_kern_endio(struct bio *bio, int err)
+{
+ struct bio_vec *bvec;
+ const int read = bio_data_dir(bio) == READ;
+ char *p = bio->bi_private;
+ int i;
+
+ __bio_for_each_segment(bvec, bio, i, 0) {
+ char *addr = page_address(bvec->bv_page);
+
+ if (read && !err)
+ memcpy(p, addr, bvec->bv_len);
+
+ __free_page(bvec->bv_page);
+ p += bvec->bv_len;
+ }
+
+ bio_put(bio);
+}
+
+/**
+ * bio_copy_kern - copy kernel address into bio
+ * @q: the struct request_queue for the bio
+ * @data: pointer to buffer to copy
+ * @len: length in bytes
+ * @gfp_mask: allocation flags for bio and page allocation
+ * @reading: data direction is READ
+ *
+ * copy the kernel address into a bio suitable for io to a block
+ * device. Returns an error pointer in case of error.
+ */
+struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len,
+ gfp_t gfp_mask, int reading)
+{
+ unsigned long kaddr = (unsigned long)data;
+ unsigned long end = (kaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ unsigned long start = kaddr >> PAGE_SHIFT;
+ const int nr_pages = end - start;
+ struct bio *bio;
+ struct bio_vec *bvec;
+ int i, ret;
+
+ bio = bio_alloc(gfp_mask, nr_pages);
+ if (!bio)
+ return ERR_PTR(-ENOMEM);
+
+ while (len) {
+ struct page *page;
+ unsigned int bytes = PAGE_SIZE;
+
+ if (bytes > len)
+ bytes = len;
+
+ page = alloc_page(q->bounce_gfp | gfp_mask);
+ if (!page) {
+ ret = -ENOMEM;
+ goto cleanup;
+ }
+
+ if (bio_add_pc_page(q, bio, page, bytes, 0) < bytes) {
+ ret = -EINVAL;
+ goto cleanup;
+ }
+
+ len -= bytes;
+ }
+
+ if (!reading) {
+ void *p = data;
+
+ bio_for_each_segment(bvec, bio, i) {
+ char *addr = page_address(bvec->bv_page);
+
+ memcpy(addr, p, bvec->bv_len);
+ p += bvec->bv_len;
+ }
+ }
+
+ bio->bi_private = data;
+ bio->bi_end_io = bio_copy_kern_endio;
+ return bio;
+cleanup:
+ bio_for_each_segment(bvec, bio, i)
+ __free_page(bvec->bv_page);
+
+ bio_put(bio);
+
+ return ERR_PTR(ret);
+}
+
/*
* bio_set_pages_dirty() and bio_check_pages_dirty() are support functions
* for performing direct-IO in BIOs.
EXPORT_SYMBOL(bio_map_user);
EXPORT_SYMBOL(bio_unmap_user);
EXPORT_SYMBOL(bio_map_kern);
+EXPORT_SYMBOL(bio_copy_kern);
EXPORT_SYMBOL(bio_pair_release);
EXPORT_SYMBOL(bio_split);
EXPORT_SYMBOL(bio_split_pool);
git.openpandora.org / pandora-kernel.git / blobdiff