diff options
Diffstat (limited to 'lib/kfifo.c')
| -rw-r--r-- | lib/kfifo.c | 115 |
1 files changed, 59 insertions, 56 deletions
diff --git a/lib/kfifo.c b/lib/kfifo.c index 12f5a347aa..a8b2eed905 100644 --- a/lib/kfifo.c +++ b/lib/kfifo.c @@ -5,13 +5,14 @@ * Copyright (C) 2009/2010 Stefani Seibold <stefani@seibold.net> */ -#include <linux/kernel.h> -#include <linux/export.h> -#include <linux/slab.h> +#include <linux/dma-mapping.h> #include <linux/err.h> +#include <linux/export.h> +#include <linux/kfifo.h> #include <linux/log2.h> +#include <linux/scatterlist.h> +#include <linux/slab.h> #include <linux/uaccess.h> -#include <linux/kfifo.h> /* * internal helper to calculate the unused elements in a fifo @@ -163,6 +164,19 @@ unsigned int __kfifo_out_peek(struct __kfifo *fifo, } EXPORT_SYMBOL(__kfifo_out_peek); +unsigned int __kfifo_out_linear(struct __kfifo *fifo, + unsigned int *tail, unsigned int n) +{ + unsigned int size = fifo->mask + 1; + unsigned int off = fifo->out & fifo->mask; + + if (tail) + *tail = off; + + return min3(n, fifo->in - fifo->out, size - off); +} +EXPORT_SYMBOL(__kfifo_out_linear); + unsigned int __kfifo_out(struct __kfifo *fifo, void *buf, unsigned int len) { @@ -292,51 +306,31 @@ int __kfifo_to_user(struct __kfifo *fifo, void __user *to, } EXPORT_SYMBOL(__kfifo_to_user); -static int setup_sgl_buf(struct scatterlist *sgl, void *buf, - int nents, unsigned int len) +static unsigned int setup_sgl_buf(struct __kfifo *fifo, struct scatterlist *sgl, + unsigned int data_offset, int nents, + unsigned int len, dma_addr_t dma) { - int n; - unsigned int l; - unsigned int off; - struct page *page; + const void *buf = fifo->data + data_offset; - if (!nents) + if (!nents || !len) return 0; - if (!len) - return 0; + sg_set_buf(sgl, buf, len); - n = 0; - page = virt_to_page(buf); - off = offset_in_page(buf); - l = 0; - - while (len >= l + PAGE_SIZE - off) { - struct page *npage; - - l += PAGE_SIZE; - buf += PAGE_SIZE; - npage = virt_to_page(buf); - if (page_to_phys(page) != page_to_phys(npage) - l) { - sg_set_page(sgl, page, l - off, off); - sgl = sg_next(sgl); - if (++n == nents || sgl == NULL) - return n; - page = npage; - len -= l - off; - l = off = 0; - } + if (dma != DMA_MAPPING_ERROR) { + sg_dma_address(sgl) = dma + data_offset; + sg_dma_len(sgl) = len; } - sg_set_page(sgl, page, len, off); - return n + 1; + + return 1; } static unsigned int setup_sgl(struct __kfifo *fifo, struct scatterlist *sgl, - int nents, unsigned int len, unsigned int off) + int nents, unsigned int len, unsigned int off, dma_addr_t dma) { unsigned int size = fifo->mask + 1; unsigned int esize = fifo->esize; - unsigned int l; + unsigned int len_to_end; unsigned int n; off &= fifo->mask; @@ -345,16 +339,17 @@ static unsigned int setup_sgl(struct __kfifo *fifo, struct scatterlist *sgl, size *= esize; len *= esize; } - l = min(len, size - off); + len_to_end = min(len, size - off); - n = setup_sgl_buf(sgl, fifo->data + off, nents, l); - n += setup_sgl_buf(sgl + n, fifo->data, nents - n, len - l); + n = setup_sgl_buf(fifo, sgl, off, nents, len_to_end, dma); + n += setup_sgl_buf(fifo, sgl + n, 0, nents - n, len - len_to_end, dma); return n; } unsigned int __kfifo_dma_in_prepare(struct __kfifo *fifo, - struct scatterlist *sgl, int nents, unsigned int len) + struct scatterlist *sgl, int nents, unsigned int len, + dma_addr_t dma) { unsigned int l; @@ -362,12 +357,13 @@ unsigned int __kfifo_dma_in_prepare(struct __kfifo *fifo, if (len > l) len = l; - return setup_sgl(fifo, sgl, nents, len, fifo->in); + return setup_sgl(fifo, sgl, nents, len, fifo->in, dma); } EXPORT_SYMBOL(__kfifo_dma_in_prepare); unsigned int __kfifo_dma_out_prepare(struct __kfifo *fifo, - struct scatterlist *sgl, int nents, unsigned int len) + struct scatterlist *sgl, int nents, unsigned int len, + dma_addr_t dma) { unsigned int l; @@ -375,7 +371,7 @@ unsigned int __kfifo_dma_out_prepare(struct __kfifo *fifo, if (len > l) len = l; - return setup_sgl(fifo, sgl, nents, len, fifo->out); + return setup_sgl(fifo, sgl, nents, len, fifo->out, dma); } EXPORT_SYMBOL(__kfifo_dma_out_prepare); @@ -473,6 +469,19 @@ unsigned int __kfifo_out_peek_r(struct __kfifo *fifo, void *buf, } EXPORT_SYMBOL(__kfifo_out_peek_r); +unsigned int __kfifo_out_linear_r(struct __kfifo *fifo, + unsigned int *tail, unsigned int n, size_t recsize) +{ + if (fifo->in == fifo->out) + return 0; + + if (tail) + *tail = fifo->out + recsize; + + return min(n, __kfifo_peek_n(fifo, recsize)); +} +EXPORT_SYMBOL(__kfifo_out_linear_r); + unsigned int __kfifo_out_r(struct __kfifo *fifo, void *buf, unsigned int len, size_t recsize) { @@ -546,7 +555,8 @@ int __kfifo_to_user_r(struct __kfifo *fifo, void __user *to, EXPORT_SYMBOL(__kfifo_to_user_r); unsigned int __kfifo_dma_in_prepare_r(struct __kfifo *fifo, - struct scatterlist *sgl, int nents, unsigned int len, size_t recsize) + struct scatterlist *sgl, int nents, unsigned int len, size_t recsize, + dma_addr_t dma) { BUG_ON(!nents); @@ -555,7 +565,7 @@ unsigned int __kfifo_dma_in_prepare_r(struct __kfifo *fifo, if (len + recsize > kfifo_unused(fifo)) return 0; - return setup_sgl(fifo, sgl, nents, len, fifo->in + recsize); + return setup_sgl(fifo, sgl, nents, len, fifo->in + recsize, dma); } EXPORT_SYMBOL(__kfifo_dma_in_prepare_r); @@ -569,7 +579,8 @@ void __kfifo_dma_in_finish_r(struct __kfifo *fifo, EXPORT_SYMBOL(__kfifo_dma_in_finish_r); unsigned int __kfifo_dma_out_prepare_r(struct __kfifo *fifo, - struct scatterlist *sgl, int nents, unsigned int len, size_t recsize) + struct scatterlist *sgl, int nents, unsigned int len, size_t recsize, + dma_addr_t dma) { BUG_ON(!nents); @@ -578,15 +589,7 @@ unsigned int __kfifo_dma_out_prepare_r(struct __kfifo *fifo, if (len + recsize > fifo->in - fifo->out) return 0; - return setup_sgl(fifo, sgl, nents, len, fifo->out + recsize); + return setup_sgl(fifo, sgl, nents, len, fifo->out + recsize, dma); } EXPORT_SYMBOL(__kfifo_dma_out_prepare_r); -void __kfifo_dma_out_finish_r(struct __kfifo *fifo, size_t recsize) -{ - unsigned int len; - - len = __kfifo_peek_n(fifo, recsize); - fifo->out += len + recsize; -} -EXPORT_SYMBOL(__kfifo_dma_out_finish_r); |