[PATCH 17/71] usb: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
From: Kirill A. Shutemov
Date: Sun Mar 20 2016 - 14:44:11 EST
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago
with promise that one day it will be possible to implement page cache with
bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_*
or PAGE_* constant should be used in a particular case, especially on the
border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Felipe Balbi <balbi@xxxxxxxxxx>
Cc: Matthew Dharm <mdharm-usb@xxxxxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/gadget/function/f_fs.c | 4 ++--
drivers/usb/gadget/legacy/inode.c | 4 ++--
drivers/usb/storage/scsiglue.c | 2 +-
3 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 8cfce105c7ee..e21ca2bd6839 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1147,8 +1147,8 @@ static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
ffs->sb = sb;
data->ffs_data = NULL;
sb->s_fs_info = ffs;
- sb->s_blocksize = PAGE_CACHE_SIZE;
- sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+ sb->s_blocksize = PAGE_SIZE;
+ sb->s_blocksize_bits = PAGE_SHIFT;
sb->s_magic = FUNCTIONFS_MAGIC;
sb->s_op = &ffs_sb_operations;
sb->s_time_gran = 1;
diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c
index 5cdaf0150a4e..e64479f882a5 100644
--- a/drivers/usb/gadget/legacy/inode.c
+++ b/drivers/usb/gadget/legacy/inode.c
@@ -1954,8 +1954,8 @@ gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
return -ENODEV;
/* superblock */
- sb->s_blocksize = PAGE_CACHE_SIZE;
- sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+ sb->s_blocksize = PAGE_SIZE;
+ sb->s_blocksize_bits = PAGE_SHIFT;
sb->s_magic = GADGETFS_MAGIC;
sb->s_op = &gadget_fs_operations;
sb->s_time_gran = 1;
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
index dba51362d2e2..90901861bfc0 100644
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -123,7 +123,7 @@ static int slave_configure(struct scsi_device *sdev)
unsigned int max_sectors = 64;
if (us->fflags & US_FL_MAX_SECTORS_MIN)
- max_sectors = PAGE_CACHE_SIZE >> 9;
+ max_sectors = PAGE_SIZE >> 9;
if (queue_max_hw_sectors(sdev->request_queue) > max_sectors)
blk_queue_max_hw_sectors(sdev->request_queue,
max_sectors);
--
2.7.0