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authorOlof Johansson <olof@lixom.net>2012-09-16 18:31:37 -0700
committerOlof Johansson <olof@lixom.net>2012-09-16 18:31:37 -0700
commit2e6185f1fea6cf88e9ce25cde1d6291ddfb3d4f0 (patch)
treec45ae7bace055c258fba5c4c6c0340b1e3f17f05 /fs/buffer.c
parent7405a749ae14f846cc2892c36d1a9343b0264b7c (diff)
parentfd301cc4e5ba839050be135a178031bcd0d363a5 (diff)
downloadlinux-next-2e6185f1fea6cf88e9ce25cde1d6291ddfb3d4f0.tar.gz
Merge tag 'tegra-for-3.7-drivers-i2c' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/drivers
From Stephen Warren: ARM: tegra: i2c driver enhancements mostly related to clocking This branch contains a number of fixes and cleanups to the Tegra I2C driver related to clocks. These are based on the common clock conversion in order to avoid duplicating the clock driver changes before and after the conversion. Finally, a bug-fix related to I2C_M_NOSTART is included. This branch is based on previous pull request tegra-for-3.7-common-clk. * tag 'tegra-for-3.7-drivers-i2c' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra: i2c: tegra: dynamically control fast clk i2c: tegra: I2_M_NOSTART functionality not supported in Tegra20 ARM: tegra: clock: remove unused clock entry for i2c ARM: tegra: clock: add connection name in i2c clock entry i2c: tegra: pass proper name for getting clock ARM: tegra: clock: add i2c fast clock entry in clock table ARM: Tegra: Add smp_twd clock for Tegra20 ARM: tegra: cpu-tegra: explicitly manage re-parenting ARM: tegra: fix overflow in tegra20_pll_clk_round_rate() ARM: tegra: Fix data type for io address ARM: tegra: remove tegra_timer from tegra_list_clks ARM: tegra30: clocks: fix the wrong tegra_audio_sync_clk_ops name ARM: tegra: clocks: separate tegra_clk_32k_ops from Tegra20 and Tegra30 ARM: tegra: Remove duplicate code ARM: tegra: Port tegra to generic clock framework ARM: tegra: Add clk_tegra structure and helper functions ARM: tegra: Rename tegra20 clock file ARM: tegra20: Separate out clk ops and clk data ARM: tegra30: Separate out clk ops and clk data ARM: tegra: fix U16 divider range check ... + sync to v3.6-rc4 Resolved remove/modify conflict in arch/arm/mach-sa1100/leds-hackkit.c caused by the sync with v3.6-rc4. Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'fs/buffer.c')
-rw-r--r--fs/buffer.c66
1 files changed, 30 insertions, 36 deletions
diff --git a/fs/buffer.c b/fs/buffer.c
index 9f6d2e41281d..58e2e7b77372 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -914,7 +914,7 @@ link_dev_buffers(struct page *page, struct buffer_head *head)
/*
* Initialise the state of a blockdev page's buffers.
*/
-static void
+static sector_t
init_page_buffers(struct page *page, struct block_device *bdev,
sector_t block, int size)
{
@@ -936,33 +936,41 @@ init_page_buffers(struct page *page, struct block_device *bdev,
block++;
bh = bh->b_this_page;
} while (bh != head);
+
+ /*
+ * Caller needs to validate requested block against end of device.
+ */
+ return end_block;
}
/*
* Create the page-cache page that contains the requested block.
*
- * This is user purely for blockdev mappings.
+ * This is used purely for blockdev mappings.
*/
-static struct page *
+static int
grow_dev_page(struct block_device *bdev, sector_t block,
- pgoff_t index, int size)
+ pgoff_t index, int size, int sizebits)
{
struct inode *inode = bdev->bd_inode;
struct page *page;
struct buffer_head *bh;
+ sector_t end_block;
+ int ret = 0; /* Will call free_more_memory() */
page = find_or_create_page(inode->i_mapping, index,
(mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS)|__GFP_MOVABLE);
if (!page)
- return NULL;
+ return ret;
BUG_ON(!PageLocked(page));
if (page_has_buffers(page)) {
bh = page_buffers(page);
if (bh->b_size == size) {
- init_page_buffers(page, bdev, block, size);
- return page;
+ end_block = init_page_buffers(page, bdev,
+ index << sizebits, size);
+ goto done;
}
if (!try_to_free_buffers(page))
goto failed;
@@ -982,14 +990,14 @@ grow_dev_page(struct block_device *bdev, sector_t block,
*/
spin_lock(&inode->i_mapping->private_lock);
link_dev_buffers(page, bh);
- init_page_buffers(page, bdev, block, size);
+ end_block = init_page_buffers(page, bdev, index << sizebits, size);
spin_unlock(&inode->i_mapping->private_lock);
- return page;
-
+done:
+ ret = (block < end_block) ? 1 : -ENXIO;
failed:
unlock_page(page);
page_cache_release(page);
- return NULL;
+ return ret;
}
/*
@@ -999,7 +1007,6 @@ failed:
static int
grow_buffers(struct block_device *bdev, sector_t block, int size)
{
- struct page *page;
pgoff_t index;
int sizebits;
@@ -1023,22 +1030,14 @@ grow_buffers(struct block_device *bdev, sector_t block, int size)
bdevname(bdev, b));
return -EIO;
}
- block = index << sizebits;
+
/* Create a page with the proper size buffers.. */
- page = grow_dev_page(bdev, block, index, size);
- if (!page)
- return 0;
- unlock_page(page);
- page_cache_release(page);
- return 1;
+ return grow_dev_page(bdev, block, index, size, sizebits);
}
static struct buffer_head *
__getblk_slow(struct block_device *bdev, sector_t block, int size)
{
- int ret;
- struct buffer_head *bh;
-
/* Size must be multiple of hard sectorsize */
if (unlikely(size & (bdev_logical_block_size(bdev)-1) ||
(size < 512 || size > PAGE_SIZE))) {
@@ -1051,21 +1050,20 @@ __getblk_slow(struct block_device *bdev, sector_t block, int size)
return NULL;
}
-retry:
- bh = __find_get_block(bdev, block, size);
- if (bh)
- return bh;
+ for (;;) {
+ struct buffer_head *bh;
+ int ret;
- ret = grow_buffers(bdev, block, size);
- if (ret == 0) {
- free_more_memory();
- goto retry;
- } else if (ret > 0) {
bh = __find_get_block(bdev, block, size);
if (bh)
return bh;
+
+ ret = grow_buffers(bdev, block, size);
+ if (ret < 0)
+ return NULL;
+ if (ret == 0)
+ free_more_memory();
}
- return NULL;
}
/*
@@ -1321,10 +1319,6 @@ EXPORT_SYMBOL(__find_get_block);
* which corresponds to the passed block_device, block and size. The
* returned buffer has its reference count incremented.
*
- * __getblk() cannot fail - it just keeps trying. If you pass it an
- * illegal block number, __getblk() will happily return a buffer_head
- * which represents the non-existent block. Very weird.
- *
* __getblk() will lock up the machine if grow_dev_page's try_to_free_buffers()
* attempt is failing. FIXME, perhaps?
*/