[kernel] r10103 - in dists/trunk/linux-2.6/debian/patches: bugfix series
Maximilian Attems
maks at alioth.debian.org
Mon Jan 14 17:15:01 UTC 2008
Author: maks
Date: Mon Jan 14 17:15:01 2008
New Revision: 10103
Log:
fw: add latest git patch
incorporates dynamic ir buffer alloc.
Added:
dists/trunk/linux-2.6/debian/patches/bugfix/fw-ohci-dyn-buffers-dma-descriptors.patch
Modified:
dists/trunk/linux-2.6/debian/patches/series/1~experimental.1
Added: dists/trunk/linux-2.6/debian/patches/bugfix/fw-ohci-dyn-buffers-dma-descriptors.patch
==============================================================================
--- (empty file)
+++ dists/trunk/linux-2.6/debian/patches/bugfix/fw-ohci-dyn-buffers-dma-descriptors.patch Mon Jan 14 17:15:01 2008
@@ -0,0 +1,416 @@
+From: David Moore <dcm at MIT.EDU>
+Date: Sun, 6 Jan 2008 22:21:41 +0000 (-0500)
+Subject: firewire: fw-ohci: Dynamically allocate buffers for DMA descriptors
+X-Git-Url: http://git.eu.kernel.org/?p=linux%2Fkernel%2Fgit%2Fieee1394%2Flinux1394-2.6.git;a=commitdiff_plain;h=6928b0009a64cc5eef5d6c43faba5241cfa5b60a
+
+firewire: fw-ohci: Dynamically allocate buffers for DMA descriptors
+
+Previously, the fw-ohci driver used fixed-length buffers for storing
+descriptors for isochronous receive DMA programs. If an application
+(such as libdc1394) generated a DMA program that was too large, fw-ohci
+would reach the limit of its fixed-sized buffer and return an error to
+userspace.
+
+This patch replaces the fixed-length ring-buffer with a linked-list of
+page-sized buffers. Additional buffers can be dynamically allocated and
+appended to the list when necessary. For a particular context, buffers
+are kept around after use and reused as necessary, so there is no
+allocation taking place after the DMA program is generated for the first
+time.
+
+In addition, the buffers it uses are coherent for DMA so there is no
+syncing required before and after writes. This syncing wasn't properly
+done in the previous version of the code.
+
+-
+
+This is the fourth version of my patch that replaces a fixed-length
+buffer for DMA descriptors with a dynamically allocated linked-list of
+buffers.
+
+As we discovered with the last attempt, new context programs are
+sometimes queued from interrupt context, making it unacceptable to call
+tasklet_disable() from context_get_descriptors().
+
+This version of the patch uses ohci->lock for all locking needs instead
+of tasklet_disable/enable. There is a new requirement that
+context_get_descriptors() be called while holding ohci->lock. It was
+already held for the AT context, so adding the requirement for the iso
+context did not seem particularly onerous. In addition, this has the
+side benefit of allowing iso queue to be safely called from concurrent
+user-space threads, which previously was not safe.
+
+Signed-off-by: David Moore <dcm at acm.org>
+Signed-off-by: Kristian Høgsberg <krh at redhat.com>
+Signed-off-by: Jarod Wilson <jwilson at redhat.com>
+
+-
+
+Fixes the following issues:
+ - Isochronous reception stopped prematurely if an application used a
+ larger buffer. (Reproduced with coriander.)
+ - Isochronous reception stopped after one or a few frames on VT630x
+ in OHCI 1.0 mode. (Fixes reception in coriander, but dvgrab still
+ doesn't work with these chips.)
+
+Patch update: struct member alignment, whitespace nits
+
+Signed-off-by: Stefan Richter <stefanr at s5r6.in-berlin.de>
+---
+
+diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c
+index 74d5d94..7ebad3c 100644
+--- a/drivers/firewire/fw-ohci.c
++++ b/drivers/firewire/fw-ohci.c
+@@ -98,17 +98,48 @@ struct context;
+ typedef int (*descriptor_callback_t)(struct context *ctx,
+ struct descriptor *d,
+ struct descriptor *last);
++
++/*
++ * A buffer that contains a block of DMA-able coherent memory used for
++ * storing a portion of a DMA descriptor program.
++ */
++struct descriptor_buffer {
++ struct list_head list;
++ dma_addr_t buffer_bus;
++ size_t buffer_size;
++ size_t used;
++ struct descriptor buffer[0];
++};
++
+ struct context {
+ struct fw_ohci *ohci;
+ u32 regs;
++ int total_allocation;
+
+- struct descriptor *buffer;
+- dma_addr_t buffer_bus;
+- size_t buffer_size;
+- struct descriptor *head_descriptor;
+- struct descriptor *tail_descriptor;
+- struct descriptor *tail_descriptor_last;
+- struct descriptor *prev_descriptor;
++ /*
++ * List of page-sized buffers for storing DMA descriptors.
++ * Head of list contains buffers in use and tail of list contains
++ * free buffers.
++ */
++ struct list_head buffer_list;
++
++ /*
++ * Pointer to a buffer inside buffer_list that contains the tail
++ * end of the current DMA program.
++ */
++ struct descriptor_buffer *buffer_tail;
++
++ /*
++ * The descriptor containing the branch address of the first
++ * descriptor that has not yet been filled by the device.
++ */
++ struct descriptor *last;
++
++ /*
++ * The last descriptor in the DMA program. It contains the branch
++ * address that must be updated upon appending a new descriptor.
++ */
++ struct descriptor *prev;
+
+ descriptor_callback_t callback;
+
+@@ -198,8 +229,6 @@ static inline struct fw_ohci *fw_ohci(struct fw_card *card)
+ #define SELF_ID_BUF_SIZE 0x800
+ #define OHCI_TCODE_PHY_PACKET 0x0e
+ #define OHCI_VERSION_1_1 0x010010
+-#define ISO_BUFFER_SIZE (64 * 1024)
+-#define AT_BUFFER_SIZE 4096
+
+ static char ohci_driver_name[] = KBUILD_MODNAME;
+
+@@ -456,71 +485,108 @@ find_branch_descriptor(struct descriptor *d, int z)
+ static void context_tasklet(unsigned long data)
+ {
+ struct context *ctx = (struct context *) data;
+- struct fw_ohci *ohci = ctx->ohci;
+ struct descriptor *d, *last;
+ u32 address;
+ int z;
++ struct descriptor_buffer *desc;
+
+- dma_sync_single_for_cpu(ohci->card.device, ctx->buffer_bus,
+- ctx->buffer_size, DMA_TO_DEVICE);
+-
+- d = ctx->tail_descriptor;
+- last = ctx->tail_descriptor_last;
+-
++ desc = list_entry(ctx->buffer_list.next,
++ struct descriptor_buffer, list);
++ last = ctx->last;
+ while (last->branch_address != 0) {
++ struct descriptor_buffer *old_desc = desc;
+ address = le32_to_cpu(last->branch_address);
+ z = address & 0xf;
+- d = ctx->buffer + (address - ctx->buffer_bus) / sizeof(*d);
++ address &= ~0xf;
++
++ /* If the branch address points to a buffer outside of the
++ * current buffer, advance to the next buffer. */
++ if (address < desc->buffer_bus ||
++ address >= desc->buffer_bus + desc->used)
++ desc = list_entry(desc->list.next,
++ struct descriptor_buffer, list);
++ d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
+ last = find_branch_descriptor(d, z);
+
+ if (!ctx->callback(ctx, d, last))
+ break;
+
+- ctx->tail_descriptor = d;
+- ctx->tail_descriptor_last = last;
++ if (old_desc != desc) {
++ /* If we've advanced to the next buffer, move the
++ * previous buffer to the free list. */
++ unsigned long flags;
++ old_desc->used = 0;
++ spin_lock_irqsave(&ctx->ohci->lock, flags);
++ list_move_tail(&old_desc->list, &ctx->buffer_list);
++ spin_unlock_irqrestore(&ctx->ohci->lock, flags);
++ }
++ ctx->last = last;
+ }
+ }
+
++/*
++ * Allocate a new buffer and add it to the list of free buffers for this
++ * context. Must be called with ohci->lock held.
++ */
++static int
++context_add_buffer(struct context *ctx)
++{
++ struct descriptor_buffer *desc;
++ dma_addr_t bus_addr;
++ int offset;
++
++ /*
++ * 16MB of descriptors should be far more than enough for any DMA
++ * program. This will catch run-away userspace or DoS attacks.
++ */
++ if (ctx->total_allocation >= 16*1024*1024)
++ return -ENOMEM;
++
++ desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
++ &bus_addr, GFP_ATOMIC);
++ if (!desc)
++ return -ENOMEM;
++
++ offset = (void *)&desc->buffer - (void *)desc;
++ desc->buffer_size = PAGE_SIZE - offset;
++ desc->buffer_bus = bus_addr + offset;
++ desc->used = 0;
++
++ list_add_tail(&desc->list, &ctx->buffer_list);
++ ctx->total_allocation += PAGE_SIZE;
++
++ return 0;
++}
++
+ static int
+ context_init(struct context *ctx, struct fw_ohci *ohci,
+- size_t buffer_size, u32 regs,
+- descriptor_callback_t callback)
++ u32 regs, descriptor_callback_t callback)
+ {
+ ctx->ohci = ohci;
+ ctx->regs = regs;
+- ctx->buffer_size = buffer_size;
+- ctx->buffer = kmalloc(buffer_size, GFP_KERNEL);
+- if (ctx->buffer == NULL)
++ ctx->total_allocation = 0;
++
++ INIT_LIST_HEAD(&ctx->buffer_list);
++ if (context_add_buffer(ctx) < 0)
+ return -ENOMEM;
+
++ ctx->buffer_tail = list_entry(ctx->buffer_list.next,
++ struct descriptor_buffer, list);
++
+ tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
+ ctx->callback = callback;
+
+- ctx->buffer_bus =
+- dma_map_single(ohci->card.device, ctx->buffer,
+- buffer_size, DMA_TO_DEVICE);
+- if (dma_mapping_error(ctx->buffer_bus)) {
+- kfree(ctx->buffer);
+- return -ENOMEM;
+- }
+-
+- ctx->head_descriptor = ctx->buffer;
+- ctx->prev_descriptor = ctx->buffer;
+- ctx->tail_descriptor = ctx->buffer;
+- ctx->tail_descriptor_last = ctx->buffer;
+-
+ /*
+ * We put a dummy descriptor in the buffer that has a NULL
+ * branch address and looks like it's been sent. That way we
+- * have a descriptor to append DMA programs to. Also, the
+- * ring buffer invariant is that it always has at least one
+- * element so that head == tail means buffer full.
++ * have a descriptor to append DMA programs to.
+ */
+-
+- memset(ctx->head_descriptor, 0, sizeof(*ctx->head_descriptor));
+- ctx->head_descriptor->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
+- ctx->head_descriptor->transfer_status = cpu_to_le16(0x8011);
+- ctx->head_descriptor++;
++ memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
++ ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
++ ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
++ ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
++ ctx->last = ctx->buffer_tail->buffer;
++ ctx->prev = ctx->buffer_tail->buffer;
+
+ return 0;
+ }
+@@ -529,35 +595,42 @@ static void
+ context_release(struct context *ctx)
+ {
+ struct fw_card *card = &ctx->ohci->card;
++ struct descriptor_buffer *desc, *tmp;
+
+- dma_unmap_single(card->device, ctx->buffer_bus,
+- ctx->buffer_size, DMA_TO_DEVICE);
+- kfree(ctx->buffer);
++ list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
++ dma_free_coherent(card->device, PAGE_SIZE, desc,
++ desc->buffer_bus -
++ ((void *)&desc->buffer - (void *)desc));
+ }
+
++/* Must be called with ohci->lock held */
+ static struct descriptor *
+ context_get_descriptors(struct context *ctx, int z, dma_addr_t *d_bus)
+ {
+- struct descriptor *d, *tail, *end;
+-
+- d = ctx->head_descriptor;
+- tail = ctx->tail_descriptor;
+- end = ctx->buffer + ctx->buffer_size / sizeof(*d);
+-
+- if (d + z <= tail) {
+- goto has_space;
+- } else if (d > tail && d + z <= end) {
+- goto has_space;
+- } else if (d > tail && ctx->buffer + z <= tail) {
+- d = ctx->buffer;
+- goto has_space;
+- }
++ struct descriptor *d = NULL;
++ struct descriptor_buffer *desc = ctx->buffer_tail;
++
++ if (z * sizeof(*d) > desc->buffer_size)
++ return NULL;
++
++ if (z * sizeof(*d) > desc->buffer_size - desc->used) {
++ /* No room for the descriptor in this buffer, so advance to the
++ * next one. */
+
+- return NULL;
++ if (desc->list.next == &ctx->buffer_list) {
++ /* If there is no free buffer next in the list,
++ * allocate one. */
++ if (context_add_buffer(ctx) < 0)
++ return NULL;
++ }
++ desc = list_entry(desc->list.next,
++ struct descriptor_buffer, list);
++ ctx->buffer_tail = desc;
++ }
+
+- has_space:
++ d = desc->buffer + desc->used / sizeof(*d);
+ memset(d, 0, z * sizeof(*d));
+- *d_bus = ctx->buffer_bus + (d - ctx->buffer) * sizeof(*d);
++ *d_bus = desc->buffer_bus + desc->used;
+
+ return d;
+ }
+@@ -567,7 +640,7 @@ static void context_run(struct context *ctx, u32 extra)
+ struct fw_ohci *ohci = ctx->ohci;
+
+ reg_write(ohci, COMMAND_PTR(ctx->regs),
+- le32_to_cpu(ctx->tail_descriptor_last->branch_address));
++ le32_to_cpu(ctx->last->branch_address));
+ reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
+ reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
+ flush_writes(ohci);
+@@ -577,15 +650,13 @@ static void context_append(struct context *ctx,
+ struct descriptor *d, int z, int extra)
+ {
+ dma_addr_t d_bus;
++ struct descriptor_buffer *desc = ctx->buffer_tail;
+
+- d_bus = ctx->buffer_bus + (d - ctx->buffer) * sizeof(*d);
++ d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
+
+- ctx->head_descriptor = d + z + extra;
+- ctx->prev_descriptor->branch_address = cpu_to_le32(d_bus | z);
+- ctx->prev_descriptor = find_branch_descriptor(d, z);
+-
+- dma_sync_single_for_device(ctx->ohci->card.device, ctx->buffer_bus,
+- ctx->buffer_size, DMA_TO_DEVICE);
++ desc->used += (z + extra) * sizeof(*d);
++ ctx->prev->branch_address = cpu_to_le32(d_bus | z);
++ ctx->prev = find_branch_descriptor(d, z);
+
+ reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
+ flush_writes(ctx->ohci);
+@@ -1571,8 +1642,7 @@ ohci_allocate_iso_context(struct fw_card *card, int type, size_t header_size)
+ if (ctx->header == NULL)
+ goto out;
+
+- retval = context_init(&ctx->context, ohci, ISO_BUFFER_SIZE,
+- regs, callback);
++ retval = context_init(&ctx->context, ohci, regs, callback);
+ if (retval < 0)
+ goto out_with_header;
+
+@@ -1933,16 +2003,22 @@ ohci_queue_iso(struct fw_iso_context *base,
+ unsigned long payload)
+ {
+ struct iso_context *ctx = container_of(base, struct iso_context, base);
++ unsigned long flags;
++ int retval;
+
++ spin_lock_irqsave(&ctx->context.ohci->lock, flags);
+ if (base->type == FW_ISO_CONTEXT_TRANSMIT)
+- return ohci_queue_iso_transmit(base, packet, buffer, payload);
++ retval = ohci_queue_iso_transmit(base, packet, buffer, payload);
+ else if (ctx->context.ohci->version >= OHCI_VERSION_1_1)
+- return ohci_queue_iso_receive_dualbuffer(base, packet,
++ retval = ohci_queue_iso_receive_dualbuffer(base, packet,
+ buffer, payload);
+ else
+- return ohci_queue_iso_receive_packet_per_buffer(base, packet,
++ retval = ohci_queue_iso_receive_packet_per_buffer(base, packet,
+ buffer,
+ payload);
++ spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
++
++ return retval;
+ }
+
+ static const struct fw_card_driver ohci_driver = {
+@@ -2014,10 +2090,10 @@ pci_probe(struct pci_dev *dev, const struct pci_device_id *ent)
+ ar_context_init(&ohci->ar_response_ctx, ohci,
+ OHCI1394_AsRspRcvContextControlSet);
+
+- context_init(&ohci->at_request_ctx, ohci, AT_BUFFER_SIZE,
++ context_init(&ohci->at_request_ctx, ohci,
+ OHCI1394_AsReqTrContextControlSet, handle_at_packet);
+
+- context_init(&ohci->at_response_ctx, ohci, AT_BUFFER_SIZE,
++ context_init(&ohci->at_response_ctx, ohci,
+ OHCI1394_AsRspTrContextControlSet, handle_at_packet);
+
+ reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
Modified: dists/trunk/linux-2.6/debian/patches/series/1~experimental.1
==============================================================================
--- dists/trunk/linux-2.6/debian/patches/series/1~experimental.1 (original)
+++ dists/trunk/linux-2.6/debian/patches/series/1~experimental.1 Mon Jan 14 17:15:01 2008
@@ -39,5 +39,6 @@
+ bugfix/arm/disable-video_bt848.patch
+ bugfix/arm/disable-scsi_acard.patch
+ bugfix/all/git-ieee1394.patch
++ bugfix/fw-ohci-dyn-buffers-dma-descriptors.patch
+ features/at76.patch
+ features/ath5k.patch
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