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 <[email protected]>
Cc: Felipe Balbi <[email protected]>
Cc: Matthew Dharm <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
---
 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

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