[ALSA] Add write support to snd-page-alloc proc file

Documentation,Memalloc module,RME HDSP driver,RME9652 driver
Add the write support to snd-page-alloc proc file for buffer pre-allocation.
Removed the pre-allocation codes via module options.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

4 files changed, 161 insertions, 104 deletions

diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt
index 226013035d72..812ed2b80b8d 100644
--- a/Documentation/sound/alsa/ALSA-Configuration.txt
+++ b/Documentation/sound/alsa/ALSA-Configuration.txt
@@ -671,7 +671,8 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
           module did formerly.  It will allocate the buffers in advance
           when any HDSP cards are found.  To make the buffer
           allocation sure, load snd-page-alloc module in the early
-          stage of boot sequence.
+          stage of boot sequence.  See "Early Buffer Allocation"
+          section.
 
   Module snd-ice1712
   ------------------
@@ -1067,7 +1068,8 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
           module did formerly.  It will allocate the buffers in advance
           when any RME9652 cards are found.  To make the buffer
           allocation sure, load snd-page-alloc module in the early
-          stage of boot sequence.
+          stage of boot sequence.  See "Early Buffer Allocation"
+          section.
 
   Module snd-sa11xx-uda1341 (on arm only)
   ---------------------------------------
@@ -1545,6 +1547,36 @@ Proc interfaces (/proc/asound)
            echo "rvplayer 0 0 block" > /proc/asound/card0/pcm0p/oss
 
 
+Early Buffer Allocation
+=======================
+
+Some drivers (e.g. hdsp) require the large contiguous buffers, and
+sometimes it's too late to find such spaces when the driver module is
+actually loaded due to memory fragmentation.  You can pre-allocate the
+PCM buffers by loading snd-page-alloc module and write commands to its
+proc file in prior, for example, in the early boot stage like
+/etc/init.d/*.local scripts.
+
+Reading the proc file /proc/drivers/snd-page-alloc shows the current
+usage of page allocation.  In writing, you can send the following
+commands to the snd-page-alloc driver:
+
+  - add VENDOR DEVICE MASK SIZE BUFFERS
+
+    VENDOR and DEVICE are PCI vendor and device IDs.  They take
+    integer numbers (0x prefix is needed for the hex).
+    MASK is the PCI DMA mask.  Pass 0 if not restricted.
+    SIZE is the size of each buffer to allocate.  You can pass
+    k and m suffix for KB and MB.  The max number is 16MB.
+    BUFFERS is the number of buffers to allocate.  It must be greater
+    than 0.  The max number is 4.
+
+  - erase
+
+    This will erase the all pre-allocated buffers which are not in
+    use.
+
+
 Links
 =====
 
diff --git a/sound/core/memalloc.c b/sound/core/memalloc.c
index 344a83fd7c2e..dbc23e35fa06 100644
--- a/sound/core/memalloc.c
+++ b/sound/core/memalloc.c
@@ -28,6 +28,7 @@
 #include <linux/pci.h>
 #include <linux/slab.h>
 #include <linux/mm.h>
+#include <asm/uaccess.h>
 #include <linux/dma-mapping.h>
 #include <linux/moduleparam.h>
 #include <asm/semaphore.h>
@@ -46,13 +47,6 @@ MODULE_LICENSE("GPL");
 #define SNDRV_CARDS     8
 #endif
 
-/* FIXME: so far only some PCI devices have the preallocation table */
-#ifdef CONFIG_PCI
-static int enable[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = 1};
-module_param_array(enable, bool, NULL, 0444);
-MODULE_PARM_DESC(enable, "Enable cards to allocate buffers.");
-#endif
-
 /*
  */
 
@@ -451,9 +445,13 @@ size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id)
         list_for_each(p, &mem_list_head) {
                 mem = list_entry(p, struct snd_mem_list, list);
                 if (mem->id == id &&
-                    ! memcmp(&mem->buffer.dev, &dmab->dev, sizeof(dmab->dev))) {
+                    (mem->buffer.dev.dev == NULL || dmab->dev.dev == NULL ||
+                     ! memcmp(&mem->buffer.dev, &dmab->dev, sizeof(dmab->dev)))) {
+                        struct device *dev = dmab->dev.dev;
                         list_del(p);
                         *dmab = mem->buffer;
+                        if (dmab->dev.dev == NULL)
+                                dmab->dev.dev = dev;
                         kfree(mem);
                         up(&list_mutex);
                         return dmab->bytes;
@@ -508,91 +506,13 @@ static void free_all_reserved_pages(void)
 }
 
 
-
-/*
- * allocation of buffers for pre-defined devices
- */
-
-#ifdef CONFIG_PCI
-/* FIXME: for pci only - other bus? */
-struct prealloc_dev {
-        unsigned short vendor;
-        unsigned short device;
-        unsigned long dma_mask;
-        unsigned int size;
-        unsigned int buffers;
-};
-
-#define HAMMERFALL_BUFFER_SIZE    (16*1024*4*(26+1)+0x10000)
-
-static struct prealloc_dev prealloc_devices[] __initdata = {
-        {
-                /* hammerfall */
-                .vendor = 0x10ee,
-                .device = 0x3fc4,
-                .dma_mask = 0xffffffff,
-                .size = HAMMERFALL_BUFFER_SIZE,
-                .buffers = 2
-        },
-        {
-                /* HDSP */
-                .vendor = 0x10ee,
-                .device = 0x3fc5,
-                .dma_mask = 0xffffffff,
-                .size = HAMMERFALL_BUFFER_SIZE,
-                .buffers = 2
-        },
-        { }, /* terminator */
-};
-
-static void __init preallocate_cards(void)
-{
-        struct pci_dev *pci = NULL;
-        int card;
-
-        card = 0;
-
-        while ((pci = pci_find_device(PCI_ANY_ID, PCI_ANY_ID, pci)) != NULL) {
-                struct prealloc_dev *dev;
-                unsigned int i;
-                if (card >= SNDRV_CARDS)
-                        break;
-                for (dev = prealloc_devices; dev->vendor; dev++) {
-                        if (dev->vendor == pci->vendor && dev->device == pci->device)
-                                break;
-                }
-                if (! dev->vendor)
-                        continue;
-                if (! enable[card++]) {
-                        printk(KERN_DEBUG "snd-page-alloc: skipping card %d, device %04x:%04x\n", card, pci->vendor, pci->device);
-                        continue;
-                }
-                        
-                if (pci_set_dma_mask(pci, dev->dma_mask) < 0 ||
-                    pci_set_consistent_dma_mask(pci, dev->dma_mask) < 0) {
-                        printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", dev->dma_mask, dev->vendor, dev->device);
-                        continue;
-                }
-                for (i = 0; i < dev->buffers; i++) {
-                        struct snd_dma_buffer dmab;
-                        memset(&dmab, 0, sizeof(dmab));
-                        if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
-                                                dev->size, &dmab) < 0)
-                                printk(KERN_WARNING "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", dev->size);
-                        else
-                                snd_dma_reserve_buf(&dmab, snd_dma_pci_buf_id(pci));
-                }
-        }
-}
-#else
-#define preallocate_cards()     /* NOP */
-#endif
-
-
 #ifdef CONFIG_PROC_FS
 /*
  * proc file interface
  */
+#define SND_MEM_PROC_FILE       "driver/snd-page-alloc"
+struct proc_dir_entry *snd_mem_proc;
+
 static int snd_mem_proc_read(char *page, char **start, off_t off,
                              int count, int *eof, void *data)
 {
@@ -621,6 +541,97 @@ static int snd_mem_proc_read(char *page, char **start, off_t off,
         up(&list_mutex);
         return len;
 }
+
+/* FIXME: for pci only - other bus? */
+#ifdef CONFIG_PCI
+#define gettoken(bufp) strsep(bufp, " \t\n")
+
+static int snd_mem_proc_write(struct file *file, const char __user *buffer,
+                              unsigned long count, void *data)
+{
+        char buf[128];
+        char *token, *p;
+
+        if (count > ARRAY_SIZE(buf) - 1)
+                count = ARRAY_SIZE(buf) - 1;
+        if (copy_from_user(buf, buffer, count))
+                return -EFAULT;
+        buf[ARRAY_SIZE(buf) - 1] = '\0';
+
+        p = buf;
+        token = gettoken(&p);
+        if (! token || *token == '#')
+                return (int)count;
+        if (strcmp(token, "add") == 0) {
+                char *endp;
+                int vendor, device, size, buffers;
+                long mask;
+                int i, alloced;
+                struct pci_dev *pci;
+
+                if ((token = gettoken(&p)) == NULL ||
+                    (vendor = simple_strtol(token, NULL, 0)) <= 0 ||
+                    (token = gettoken(&p)) == NULL ||
+                    (device = simple_strtol(token, NULL, 0)) <= 0 ||
+                    (token = gettoken(&p)) == NULL ||
+                    (mask = simple_strtol(token, NULL, 0)) < 0 ||
+                    (token = gettoken(&p)) == NULL ||
+                    (size = memparse(token, &endp)) < 64*1024 ||
+                    size > 16*1024*1024 /* too big */ ||
+                    (token = gettoken(&p)) == NULL ||
+                    (buffers = simple_strtol(token, NULL, 0)) <= 0 ||
+                    buffers > 4) {
+                        printk(KERN_ERR "snd-page-alloc: invalid proc write format\n");
+                        return (int)count;
+                }
+                vendor &= 0xffff;
+                device &= 0xffff;
+
+                alloced = 0;
+                pci = NULL;
+                while ((pci = pci_find_device(vendor, device, pci)) != NULL) {
+                        if (mask > 0 && mask < 0xffffffff) {
+                                if (pci_set_dma_mask(pci, mask) < 0 ||
+                                    pci_set_consistent_dma_mask(pci, mask) < 0) {
+                                        printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", mask, vendor, device);
+                                        return (int)count;
+                                }
+                        }
+                        for (i = 0; i < buffers; i++) {
+                                struct snd_dma_buffer dmab;
+                                memset(&dmab, 0, sizeof(dmab));
+                                if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
+                                                        size, &dmab) < 0) {
+                                        printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
+                                        return (int)count;
+                                }
+                                snd_dma_reserve_buf(&dmab, snd_dma_pci_buf_id(pci));
+                        }
+                        alloced++;
+                }
+                if (! alloced) {
+                        for (i = 0; i < buffers; i++) {
+                                struct snd_dma_buffer dmab;
+                                memset(&dmab, 0, sizeof(dmab));
+                                /* FIXME: We can allocate only in ZONE_DMA
+                                 * without a device pointer!
+                                 */
+                                if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, NULL,
+                                                        size, &dmab) < 0) {
+                                        printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
+                                        break;
+                                }
+                                snd_dma_reserve_buf(&dmab, (unsigned int)((vendor << 16) | device));
+                        }
+                }
+        } else if (strcmp(token, "erase") == 0)
+                /* FIXME: need for releasing each buffer chunk? */
+                free_all_reserved_pages();
+        else
+                printk(KERN_ERR "snd-page-alloc: invalid proc cmd\n");
+        return (int)count;
+}
+#endif /* CONFIG_PCI */
 #endif /* CONFIG_PROC_FS */
 
 /*
@@ -630,15 +641,21 @@ static int snd_mem_proc_read(char *page, char **start, off_t off,
 static int __init snd_mem_init(void)
 {
 #ifdef CONFIG_PROC_FS
-        create_proc_read_entry("driver/snd-page-alloc", 0, NULL, snd_mem_proc_read, NULL);
+        snd_mem_proc = create_proc_entry(SND_MEM_PROC_FILE, 0644, NULL);
+        if (snd_mem_proc) {
+                snd_mem_proc->read_proc = snd_mem_proc_read;
+#ifdef CONFIG_PCI
+                snd_mem_proc->write_proc = snd_mem_proc_write;
+#endif
+        }
 #endif
-        preallocate_cards();
         return 0;
 }
 
 static void __exit snd_mem_exit(void)
 {
-        remove_proc_entry("driver/snd-page-alloc", NULL);
+        if (snd_mem_proc)
+                remove_proc_entry(SND_MEM_PROC_FILE, NULL);
         free_all_reserved_pages();
         if (snd_allocated_pages > 0)
                 printk(KERN_ERR "snd-malloc: Memory leak?  pages not freed = %li\n", snd_allocated_pages);
diff --git a/sound/pci/rme9652/hdsp.c b/sound/pci/rme9652/hdsp.c
index b35ed5f0c042..a673cc438b91 100644
--- a/sound/pci/rme9652/hdsp.c
+++ b/sound/pci/rme9652/hdsp.c
@@ -559,18 +559,22 @@ static int snd_hammerfall_get_buffer(struct pci_dev *pci, struct snd_dma_buffer
 {
         dmab->dev.type = SNDRV_DMA_TYPE_DEV;
         dmab->dev.dev = snd_dma_pci_data(pci);
-        if (! snd_dma_get_reserved_buf(dmab, snd_dma_pci_buf_id(pci))) {
-                if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
-                                        size, dmab) < 0)
-                        return -ENOMEM;
+        if (snd_dma_get_reserved_buf(dmab, snd_dma_pci_buf_id(pci))) {
+                if (dmab->bytes >= size)
+                        return 0;
         }
+        if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
+                                size, dmab) < 0)
+                return -ENOMEM;
         return 0;
 }
 
 static void snd_hammerfall_free_buffer(struct snd_dma_buffer *dmab, struct pci_dev *pci)
 {
-        if (dmab->area)
+        if (dmab->area) {
+                dmab->dev.dev = NULL; /* make it anonymous */
                 snd_dma_reserve_buf(dmab, snd_dma_pci_buf_id(pci));
+        }
 }
 
 
diff --git a/sound/pci/rme9652/rme9652.c b/sound/pci/rme9652/rme9652.c
index 5861f234af21..f3037402d58f 100644
--- a/sound/pci/rme9652/rme9652.c
+++ b/sound/pci/rme9652/rme9652.c
@@ -303,18 +303,22 @@ static int snd_hammerfall_get_buffer(struct pci_dev *pci, struct snd_dma_buffer
 {
         dmab->dev.type = SNDRV_DMA_TYPE_DEV;
         dmab->dev.dev = snd_dma_pci_data(pci);
-        if (! snd_dma_get_reserved_buf(dmab, snd_dma_pci_buf_id(pci))) {
-                if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
-                                        size, dmab) < 0)
-                        return -ENOMEM;
+        if (snd_dma_get_reserved_buf(dmab, snd_dma_pci_buf_id(pci))) {
+                if (dmab->bytes >= size)
+                        return 0;
         }
+        if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
+                                size, dmab) < 0)
+                return -ENOMEM;
         return 0;
 }
 
 static void snd_hammerfall_free_buffer(struct snd_dma_buffer *dmab, struct pci_dev *pci)
 {
-        if (dmab->area)
+        if (dmab->area) {
+                dmab->dev.dev = NULL; /* make it anonymous */
                 snd_dma_reserve_buf(dmab, snd_dma_pci_buf_id(pci));
+        }
 }