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-rw-r--r--drivers/char/ps3flash.c209
1 files changed, 104 insertions, 105 deletions
diff --git a/drivers/char/ps3flash.c b/drivers/char/ps3flash.c
index f7f21f4..d884d31 100644
--- a/drivers/char/ps3flash.c
+++ b/drivers/char/ps3flash.c
@@ -33,13 +33,16 @@
struct ps3flash_private {
struct mutex mutex; /* Bounce buffer mutex */
+ u64 chunk_sectors;
+ int tag; /* Start sector of buffer, -1 if invalid */
+ bool dirty;
};
static struct ps3_storage_device *ps3flash_dev;
-static ssize_t ps3flash_read_write_sectors(struct ps3_storage_device *dev,
- u64 lpar, u64 start_sector,
- u64 sectors, int write)
+static int ps3flash_read_write_sectors(struct ps3_storage_device *dev,
+ u64 lpar, u64 start_sector, u64 sectors,
+ int write)
{
u64 res = ps3stor_read_write_sectors(dev, lpar, start_sector, sectors,
write);
@@ -48,33 +51,55 @@ static ssize_t ps3flash_read_write_sectors(struct ps3_storage_device *dev,
__LINE__, write ? "write" : "read", res);
return -EIO;
}
- return sectors;
+ return 0;
}
-static ssize_t ps3flash_read_sectors(struct ps3_storage_device *dev,
- u64 start_sector, u64 sectors,
- unsigned int sector_offset)
+static int ps3flash_writeback(struct ps3_storage_device *dev)
{
- u64 max_sectors, lpar;
+ struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
+ int res;
- max_sectors = dev->bounce_size / dev->blk_size;
- if (sectors > max_sectors) {
- dev_dbg(&dev->sbd.core, "%s:%u Limiting sectors to %llu\n",
- __func__, __LINE__, max_sectors);
- sectors = max_sectors;
- }
+ if (!priv->dirty || priv->tag < 0)
+ return 0;
+
+ res = ps3flash_read_write_sectors(dev, dev->bounce_lpar, priv->tag,
+ priv->chunk_sectors, 1);
+ if (res)
+ return res;
- lpar = dev->bounce_lpar + sector_offset * dev->blk_size;
- return ps3flash_read_write_sectors(dev, lpar, start_sector, sectors,
- 0);
+ priv->dirty = false;
+ return 0;
}
-static ssize_t ps3flash_write_chunk(struct ps3_storage_device *dev,
- u64 start_sector)
+static int ps3flash_fetch(struct ps3_storage_device *dev, u64 start_sector,
+ u64 sectors)
{
- u64 sectors = dev->bounce_size / dev->blk_size;
- return ps3flash_read_write_sectors(dev, dev->bounce_lpar, start_sector,
- sectors, 1);
+ struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
+ unsigned int tag, offset;
+ u64 lpar;
+ int res;
+
+ offset = start_sector % priv->chunk_sectors;
+ tag = start_sector - offset;
+ if (tag == priv->tag)
+ return 0;
+
+ res = ps3flash_writeback(dev);
+ if (res)
+ return res;
+
+ priv->tag = -1;
+
+ lpar = dev->bounce_lpar + offset * dev->blk_size;
+ res = ps3flash_read_write_sectors(dev, lpar, start_sector, sectors, 0);
+ if (res)
+ return res;
+
+ /* We don't bother caching reads smaller than the chunk size */
+ if (sectors == priv->chunk_sectors)
+ priv->tag = tag;
+
+ return 0;
}
static loff_t ps3flash_llseek(struct file *file, loff_t offset, int origin)
@@ -109,8 +134,8 @@ static ssize_t ps3flash_read(char __user *userbuf, void *kernelbuf,
{
struct ps3_storage_device *dev = ps3flash_dev;
struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
- u64 size, start_sector, end_sector, offset;
- ssize_t sectors_read;
+ u64 size, start_sector, end_sector, offset, sectors;
+ int res;
size_t remaining, n;
const void *src;
@@ -130,30 +155,29 @@ static ssize_t ps3flash_read(char __user *userbuf, void *kernelbuf,
}
start_sector = *pos / dev->blk_size;
- offset = *pos % dev->blk_size;
+ offset = *pos % dev->bounce_size;
end_sector = DIV_ROUND_UP(*pos + count, dev->blk_size);
remaining = count;
do {
+ sectors = min(end_sector - start_sector,
+ priv->chunk_sectors -
+ start_sector % priv->chunk_sectors);
+
mutex_lock(&priv->mutex);
- sectors_read = ps3flash_read_sectors(dev, start_sector,
- end_sector-start_sector,
- 0);
- if (sectors_read < 0) {
- mutex_unlock(&priv->mutex);
+ res = ps3flash_fetch(dev, start_sector, sectors);
+ if (res)
goto fail;
- }
- n = min_t(u64, remaining, sectors_read*dev->blk_size-offset);
- src = dev->bounce_buf+offset;
+ n = min_t(u64, remaining, dev->bounce_size - offset);
+ src = dev->bounce_buf + offset;
dev_dbg(&dev->sbd.core,
"%s:%u: copy %lu bytes from 0x%p to U0x%p/K0x%p\n",
__func__, __LINE__, n, src, userbuf, kernelbuf);
if (userbuf) {
if (copy_to_user(userbuf, src, n)) {
- mutex_unlock(&priv->mutex);
- sectors_read = -EFAULT;
+ res = -EFAULT;
goto fail;
}
userbuf += n;
@@ -167,14 +191,15 @@ static ssize_t ps3flash_read(char __user *userbuf, void *kernelbuf,
*pos += n;
remaining -= n;
- start_sector += sectors_read;
+ start_sector += sectors;
offset = 0;
} while (remaining > 0);
return count;
fail:
- return sectors_read;
+ mutex_unlock(&priv->mutex);
+ return res;
}
static ssize_t ps3flash_write(const char __user *userbuf,
@@ -182,11 +207,9 @@ static ssize_t ps3flash_write(const char __user *userbuf,
{
struct ps3_storage_device *dev = ps3flash_dev;
struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
- u64 size, chunk_sectors, start_write_sector, end_write_sector,
- end_read_sector, start_read_sector, head, tail, offset;
- ssize_t res;
+ u64 size, sector, offset;
+ int res = 0;
size_t remaining, n;
- unsigned int sec_off;
void *dst;
dev_dbg(&dev->sbd.core,
@@ -204,71 +227,23 @@ static ssize_t ps3flash_write(const char __user *userbuf,
count = size - *pos;
}
- chunk_sectors = dev->bounce_size / dev->blk_size;
-
- start_write_sector = *pos / dev->bounce_size * chunk_sectors;
+ sector = *pos / dev->bounce_size * priv->chunk_sectors;
offset = *pos % dev->bounce_size;
- end_write_sector = DIV_ROUND_UP(*pos + count, dev->bounce_size) *
- chunk_sectors;
-
- end_read_sector = DIV_ROUND_UP(*pos, dev->blk_size);
- start_read_sector = (*pos + count) / dev->blk_size;
-
- /*
- * As we have to write in 256 KiB chunks, while we can read in blk_size
- * (usually 512 bytes) chunks, we perform the following steps:
- * 1. Read from start_write_sector to end_read_sector ("head")
- * 2. Read from start_read_sector to end_write_sector ("tail")
- * 3. Copy data to buffer
- * 4. Write from start_write_sector to end_write_sector
- * All of this is complicated by using only one 256 KiB bounce buffer.
- */
-
- head = end_read_sector - start_write_sector;
- tail = end_write_sector - start_read_sector;
remaining = count;
do {
+ n = min_t(u64, remaining, dev->bounce_size - offset);
+
mutex_lock(&priv->mutex);
- if (end_read_sector >= start_read_sector) {
- /* Merge head and tail */
- dev_dbg(&dev->sbd.core,
- "Merged head and tail: %llu sectors at %llu\n",
- chunk_sectors, start_write_sector);
- res = ps3flash_read_sectors(dev, start_write_sector,
- chunk_sectors, 0);
- if (res < 0)
- goto fail;
- } else {
- if (head) {
- /* Read head */
- dev_dbg(&dev->sbd.core,
- "head: %llu sectors at %llu\n", head,
- start_write_sector);
- res = ps3flash_read_sectors(dev,
- start_write_sector,
- head, 0);
- if (res < 0)
- goto fail;
- }
- if (start_read_sector <
- start_write_sector+chunk_sectors) {
- /* Read tail */
- dev_dbg(&dev->sbd.core,
- "tail: %llu sectors at %llu\n", tail,
- start_read_sector);
- sec_off = start_read_sector-start_write_sector;
- res = ps3flash_read_sectors(dev,
- start_read_sector,
- tail, sec_off);
- if (res < 0)
- goto fail;
- }
- }
+ if (n != dev->bounce_size)
+ res = ps3flash_fetch(dev, sector, priv->chunk_sectors);
+ else if (sector != priv->tag)
+ res = ps3flash_writeback(dev);
+ if (res)
+ goto fail;
- n = min_t(u64, remaining, dev->bounce_size-offset);
- dst = dev->bounce_buf+offset;
+ dst = dev->bounce_buf + offset;
dev_dbg(&dev->sbd.core,
"%s:%u: copy %lu bytes from U0x%p/K0x%p to 0x%p\n",
__func__, __LINE__, n, userbuf, kernelbuf, dst);
@@ -284,16 +259,14 @@ static ssize_t ps3flash_write(const char __user *userbuf,
kernelbuf += n;
}
- res = ps3flash_write_chunk(dev, start_write_sector);
- if (res < 0)
- goto fail;
+ priv->tag = sector;
+ priv->dirty = true;
mutex_unlock(&priv->mutex);
*pos += n;
remaining -= n;
- start_write_sector += chunk_sectors;
- head = 0;
+ sector += priv->chunk_sectors;
offset = 0;
} while (remaining > 0);
@@ -324,9 +297,31 @@ static ssize_t ps3flash_kernel_read(void *buf, size_t count, loff_t pos)
static ssize_t ps3flash_kernel_write(const void *buf, size_t count,
loff_t pos)
{
- return ps3flash_write(NULL, buf, count, &pos);
+ ssize_t res;
+ int wb;
+
+ res = ps3flash_write(NULL, buf, count, &pos);
+ if (res < 0)
+ return res;
+
+ /* Make kernel writes synchronous */
+ wb = ps3flash_writeback(ps3flash_dev);
+ if (wb)
+ return wb;
+
+ return res;
}
+static int ps3flash_flush(struct file *file, fl_owner_t id)
+{
+ return ps3flash_writeback(ps3flash_dev);
+}
+
+static int ps3flash_fsync(struct file *file, struct dentry *dentry,
+ int datasync)
+{
+ return ps3flash_writeback(ps3flash_dev);
+}
static irqreturn_t ps3flash_interrupt(int irq, void *data)
{
@@ -356,6 +351,8 @@ static const struct file_operations ps3flash_fops = {
.llseek = ps3flash_llseek,
.read = ps3flash_user_read,
.write = ps3flash_user_write,
+ .flush = ps3flash_flush,
+ .fsync = ps3flash_fsync,
};
static const struct ps3_os_area_flash_ops ps3flash_kernel_ops = {
@@ -411,9 +408,11 @@ static int __devinit ps3flash_probe(struct ps3_system_bus_device *_dev)
ps3_system_bus_set_drvdata(&dev->sbd, priv);
mutex_init(&priv->mutex);
+ priv->tag = -1;
dev->bounce_size = ps3flash_bounce_buffer.size;
dev->bounce_buf = ps3flash_bounce_buffer.address;
+ priv->chunk_sectors = dev->bounce_size / dev->blk_size;
error = ps3stor_setup(dev, ps3flash_interrupt);
if (error)
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