[PATCH 37/71] fuse: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

From: Kirill A. Shutemov
Date: Sun Mar 20 2016 - 14:50:44 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: Miklos Szeredi <miklos@xxxxxxxxxx>
---
fs/fuse/dev.c | 26 ++++++++++-----------
fs/fuse/file.c | 72 ++++++++++++++++++++++++++++-----------------------------
fs/fuse/inode.c | 16 ++++++-------
3 files changed, 57 insertions(+), 57 deletions(-)

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index ebb5e37455a0..cbece1221417 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -897,7 +897,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
return err;
}

- page_cache_get(newpage);
+ get_page(newpage);

if (!(buf->flags & PIPE_BUF_FLAG_LRU))
lru_cache_add_file(newpage);
@@ -912,12 +912,12 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)

if (err) {
unlock_page(newpage);
- page_cache_release(newpage);
+ put_page(newpage);
return err;
}

unlock_page(oldpage);
- page_cache_release(oldpage);
+ put_page(oldpage);
cs->len = 0;

return 0;
@@ -951,7 +951,7 @@ static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
fuse_copy_finish(cs);

buf = cs->pipebufs;
- page_cache_get(page);
+ get_page(page);
buf->page = page;
buf->offset = offset;
buf->len = count;
@@ -1435,7 +1435,7 @@ out_unlock:

out:
for (; page_nr < cs.nr_segs; page_nr++)
- page_cache_release(bufs[page_nr].page);
+ put_page(bufs[page_nr].page);

kfree(bufs);
return ret;
@@ -1632,8 +1632,8 @@ static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
goto out_up_killsb;

mapping = inode->i_mapping;
- index = outarg.offset >> PAGE_CACHE_SHIFT;
- offset = outarg.offset & ~PAGE_CACHE_MASK;
+ index = outarg.offset >> PAGE_SHIFT;
+ offset = outarg.offset & ~PAGE_MASK;
file_size = i_size_read(inode);
end = outarg.offset + outarg.size;
if (end > file_size) {
@@ -1652,13 +1652,13 @@ static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
if (!page)
goto out_iput;

- this_num = min_t(unsigned, num, PAGE_CACHE_SIZE - offset);
+ this_num = min_t(unsigned, num, PAGE_SIZE - offset);
err = fuse_copy_page(cs, &page, offset, this_num, 0);
if (!err && offset == 0 &&
- (this_num == PAGE_CACHE_SIZE || file_size == end))
+ (this_num == PAGE_SIZE || file_size == end))
SetPageUptodate(page);
unlock_page(page);
- page_cache_release(page);
+ put_page(page);

if (err)
goto out_iput;
@@ -1697,7 +1697,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
size_t total_len = 0;
int num_pages;

- offset = outarg->offset & ~PAGE_CACHE_MASK;
+ offset = outarg->offset & ~PAGE_MASK;
file_size = i_size_read(inode);

num = outarg->size;
@@ -1720,7 +1720,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
req->page_descs[0].offset = offset;
req->end = fuse_retrieve_end;

- index = outarg->offset >> PAGE_CACHE_SHIFT;
+ index = outarg->offset >> PAGE_SHIFT;

while (num && req->num_pages < num_pages) {
struct page *page;
@@ -1730,7 +1730,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
if (!page)
break;

- this_num = min_t(unsigned, num, PAGE_CACHE_SIZE - offset);
+ this_num = min_t(unsigned, num, PAGE_SIZE - offset);
req->pages[req->num_pages] = page;
req->page_descs[req->num_pages].length = this_num;
req->num_pages++;
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index b03d253ece15..6fc09c6fc80c 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -348,7 +348,7 @@ static bool fuse_range_is_writeback(struct inode *inode, pgoff_t idx_from,
pgoff_t curr_index;

BUG_ON(req->inode != inode);
- curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT;
+ curr_index = req->misc.write.in.offset >> PAGE_SHIFT;
if (idx_from < curr_index + req->num_pages &&
curr_index <= idx_to) {
found = true;
@@ -676,11 +676,11 @@ static void fuse_short_read(struct fuse_req *req, struct inode *inode,
* present there.
*/
int i;
- int start_idx = num_read >> PAGE_CACHE_SHIFT;
- size_t off = num_read & (PAGE_CACHE_SIZE - 1);
+ int start_idx = num_read >> PAGE_SHIFT;
+ size_t off = num_read & (PAGE_SIZE - 1);

for (i = start_idx; i < req->num_pages; i++) {
- zero_user_segment(req->pages[i], off, PAGE_CACHE_SIZE);
+ zero_user_segment(req->pages[i], off, PAGE_SIZE);
off = 0;
}
} else {
@@ -697,7 +697,7 @@ static int fuse_do_readpage(struct file *file, struct page *page)
struct fuse_req *req;
size_t num_read;
loff_t pos = page_offset(page);
- size_t count = PAGE_CACHE_SIZE;
+ size_t count = PAGE_SIZE;
u64 attr_ver;
int err;

@@ -782,7 +782,7 @@ static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
else
SetPageError(page);
unlock_page(page);
- page_cache_release(page);
+ put_page(page);
}
if (req->ff)
fuse_file_put(req->ff, false);
@@ -793,7 +793,7 @@ static void fuse_send_readpages(struct fuse_req *req, struct file *file)
struct fuse_file *ff = file->private_data;
struct fuse_conn *fc = ff->fc;
loff_t pos = page_offset(req->pages[0]);
- size_t count = req->num_pages << PAGE_CACHE_SHIFT;
+ size_t count = req->num_pages << PAGE_SHIFT;

req->out.argpages = 1;
req->out.page_zeroing = 1;
@@ -829,7 +829,7 @@ static int fuse_readpages_fill(void *_data, struct page *page)

if (req->num_pages &&
(req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
- (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
+ (req->num_pages + 1) * PAGE_SIZE > fc->max_read ||
req->pages[req->num_pages - 1]->index + 1 != page->index)) {
int nr_alloc = min_t(unsigned, data->nr_pages,
FUSE_MAX_PAGES_PER_REQ);
@@ -851,7 +851,7 @@ static int fuse_readpages_fill(void *_data, struct page *page)
return -EIO;
}

- page_cache_get(page);
+ get_page(page);
req->pages[req->num_pages] = page;
req->page_descs[req->num_pages].length = PAGE_SIZE;
req->num_pages++;
@@ -996,17 +996,17 @@ static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file,
for (i = 0; i < req->num_pages; i++) {
struct page *page = req->pages[i];

- if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE)
+ if (!req->out.h.error && !offset && count >= PAGE_SIZE)
SetPageUptodate(page);

- if (count > PAGE_CACHE_SIZE - offset)
- count -= PAGE_CACHE_SIZE - offset;
+ if (count > PAGE_SIZE - offset)
+ count -= PAGE_SIZE - offset;
else
count = 0;
offset = 0;

unlock_page(page);
- page_cache_release(page);
+ put_page(page);
}

return res;
@@ -1017,7 +1017,7 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req,
struct iov_iter *ii, loff_t pos)
{
struct fuse_conn *fc = get_fuse_conn(mapping->host);
- unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
+ unsigned offset = pos & (PAGE_SIZE - 1);
size_t count = 0;
int err;

@@ -1027,8 +1027,8 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req,
do {
size_t tmp;
struct page *page;
- pgoff_t index = pos >> PAGE_CACHE_SHIFT;
- size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset,
+ pgoff_t index = pos >> PAGE_SHIFT;
+ size_t bytes = min_t(size_t, PAGE_SIZE - offset,
iov_iter_count(ii));

bytes = min_t(size_t, bytes, fc->max_write - count);
@@ -1052,7 +1052,7 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req,
iov_iter_advance(ii, tmp);
if (!tmp) {
unlock_page(page);
- page_cache_release(page);
+ put_page(page);
bytes = min(bytes, iov_iter_single_seg_count(ii));
goto again;
}
@@ -1065,7 +1065,7 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req,
count += tmp;
pos += tmp;
offset += tmp;
- if (offset == PAGE_CACHE_SIZE)
+ if (offset == PAGE_SIZE)
offset = 0;

if (!fc->big_writes)
@@ -1079,8 +1079,8 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req,
static inline unsigned fuse_wr_pages(loff_t pos, size_t len)
{
return min_t(unsigned,
- ((pos + len - 1) >> PAGE_CACHE_SHIFT) -
- (pos >> PAGE_CACHE_SHIFT) + 1,
+ ((pos + len - 1) >> PAGE_SHIFT) -
+ (pos >> PAGE_SHIFT) + 1,
FUSE_MAX_PAGES_PER_REQ);
}

@@ -1198,8 +1198,8 @@ static ssize_t fuse_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
goto out;

invalidate_mapping_pages(file->f_mapping,
- pos >> PAGE_CACHE_SHIFT,
- endbyte >> PAGE_CACHE_SHIFT);
+ pos >> PAGE_SHIFT,
+ endbyte >> PAGE_SHIFT);

written += written_buffered;
iocb->ki_pos = pos + written_buffered;
@@ -1308,8 +1308,8 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
size_t nmax = write ? fc->max_write : fc->max_read;
loff_t pos = *ppos;
size_t count = iov_iter_count(iter);
- pgoff_t idx_from = pos >> PAGE_CACHE_SHIFT;
- pgoff_t idx_to = (pos + count - 1) >> PAGE_CACHE_SHIFT;
+ pgoff_t idx_from = pos >> PAGE_SHIFT;
+ pgoff_t idx_to = (pos + count - 1) >> PAGE_SHIFT;
ssize_t res = 0;
struct fuse_req *req;

@@ -1460,7 +1460,7 @@ __acquires(fc->lock)
{
struct fuse_inode *fi = get_fuse_inode(req->inode);
struct fuse_write_in *inarg = &req->misc.write.in;
- __u64 data_size = req->num_pages * PAGE_CACHE_SIZE;
+ __u64 data_size = req->num_pages * PAGE_SIZE;

if (!fc->connected)
goto out_free;
@@ -1721,7 +1721,7 @@ static bool fuse_writepage_in_flight(struct fuse_req *new_req,
list_del(&new_req->writepages_entry);
list_for_each_entry(old_req, &fi->writepages, writepages_entry) {
BUG_ON(old_req->inode != new_req->inode);
- curr_index = old_req->misc.write.in.offset >> PAGE_CACHE_SHIFT;
+ curr_index = old_req->misc.write.in.offset >> PAGE_SHIFT;
if (curr_index <= page->index &&
page->index < curr_index + old_req->num_pages) {
found = true;
@@ -1736,7 +1736,7 @@ static bool fuse_writepage_in_flight(struct fuse_req *new_req,
new_req->num_pages = 1;
for (tmp = old_req; tmp != NULL; tmp = tmp->misc.write.next) {
BUG_ON(tmp->inode != new_req->inode);
- curr_index = tmp->misc.write.in.offset >> PAGE_CACHE_SHIFT;
+ curr_index = tmp->misc.write.in.offset >> PAGE_SHIFT;
if (tmp->num_pages == 1 &&
curr_index == page->index) {
old_req = tmp;
@@ -1793,7 +1793,7 @@ static int fuse_writepages_fill(struct page *page,

if (req && req->num_pages &&
(is_writeback || req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
- (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_write ||
+ (req->num_pages + 1) * PAGE_SIZE > fc->max_write ||
data->orig_pages[req->num_pages - 1]->index + 1 != page->index)) {
fuse_writepages_send(data);
data->req = NULL;
@@ -1918,7 +1918,7 @@ static int fuse_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
- pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+ pgoff_t index = pos >> PAGE_SHIFT;
struct fuse_conn *fc = get_fuse_conn(file_inode(file));
struct page *page;
loff_t fsize;
@@ -1932,15 +1932,15 @@ static int fuse_write_begin(struct file *file, struct address_space *mapping,

fuse_wait_on_page_writeback(mapping->host, page->index);

- if (PageUptodate(page) || len == PAGE_CACHE_SIZE)
+ if (PageUptodate(page) || len == PAGE_SIZE)
goto success;
/*
* Check if the start this page comes after the end of file, in which
* case the readpage can be optimized away.
*/
fsize = i_size_read(mapping->host);
- if (fsize <= (pos & PAGE_CACHE_MASK)) {
- size_t off = pos & ~PAGE_CACHE_MASK;
+ if (fsize <= (pos & PAGE_MASK)) {
+ size_t off = pos & ~PAGE_MASK;
if (off)
zero_user_segment(page, 0, off);
goto success;
@@ -1954,7 +1954,7 @@ success:

cleanup:
unlock_page(page);
- page_cache_release(page);
+ put_page(page);
error:
return err;
}
@@ -1967,16 +1967,16 @@ static int fuse_write_end(struct file *file, struct address_space *mapping,

if (!PageUptodate(page)) {
/* Zero any unwritten bytes at the end of the page */
- size_t endoff = (pos + copied) & ~PAGE_CACHE_MASK;
+ size_t endoff = (pos + copied) & ~PAGE_MASK;
if (endoff)
- zero_user_segment(page, endoff, PAGE_CACHE_SIZE);
+ zero_user_segment(page, endoff, PAGE_SIZE);
SetPageUptodate(page);
}

fuse_write_update_size(inode, pos + copied);
set_page_dirty(page);
unlock_page(page);
- page_cache_release(page);
+ put_page(page);

return copied;
}
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 4d69d5c0bedc..1ce67668a8e1 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -339,11 +339,11 @@ int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,

fuse_invalidate_attr(inode);
if (offset >= 0) {
- pg_start = offset >> PAGE_CACHE_SHIFT;
+ pg_start = offset >> PAGE_SHIFT;
if (len <= 0)
pg_end = -1;
else
- pg_end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
+ pg_end = (offset + len - 1) >> PAGE_SHIFT;
invalidate_inode_pages2_range(inode->i_mapping,
pg_start, pg_end);
}
@@ -864,7 +864,7 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
process_init_limits(fc, arg);

if (arg->minor >= 6) {
- ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
+ ra_pages = arg->max_readahead / PAGE_SIZE;
if (arg->flags & FUSE_ASYNC_READ)
fc->async_read = 1;
if (!(arg->flags & FUSE_POSIX_LOCKS))
@@ -901,7 +901,7 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
if (arg->time_gran && arg->time_gran <= 1000000000)
fc->sb->s_time_gran = arg->time_gran;
} else {
- ra_pages = fc->max_read / PAGE_CACHE_SIZE;
+ ra_pages = fc->max_read / PAGE_SIZE;
fc->no_lock = 1;
fc->no_flock = 1;
}
@@ -922,7 +922,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)

arg->major = FUSE_KERNEL_VERSION;
arg->minor = FUSE_KERNEL_MINOR_VERSION;
- arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
+ arg->max_readahead = fc->bdi.ra_pages * PAGE_SIZE;
arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
@@ -955,7 +955,7 @@ static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
int err;

fc->bdi.name = "fuse";
- fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
+ fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_SIZE;
/* fuse does it's own writeback accounting */
fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT;

@@ -1053,8 +1053,8 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
goto err;
#endif
} else {
- 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 = FUSE_SUPER_MAGIC;
sb->s_op = &fuse_super_operations;
--
2.7.0