orangefs: revamp block sizes

Now the superblock block size is PAGE_SIZE.  The inode block size is
PAGE_SIZE for directories and symlinks, but is the server-reported
block size for regular files.

The block size in the OrangeFS private inode is now deleted.  Stat
now reports PAGE_SIZE for directories and symlinks and the
server-reported block size for regular files.

The user-space visible change is that the block size for directores
and symlinks and the superblock is now PAGE_SIZE rather than the size of
the client-core shared memory buffers, which was typically four
megabytes.

Reported-by: Becky Ligon <ligon@clemson.edu>
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Cc: hubcap@omnibond.com
Cc: walt@omnibond.com
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

fs/orangefs/inode.c

@@ -20,8 +20,8 @@ static int read_one_page(struct page *page)
 	int max_block;
 	ssize_t bytes_read = 0;
 	struct inode *inode = page->mapping->host;
-	const __u32 blocksize = PAGE_SIZE;	/* inode->i_blksize */
-	const __u32 blockbits = PAGE_SHIFT;	/* inode->i_blkbits */
+	const __u32 blocksize = PAGE_SIZE;
+	const __u32 blockbits = PAGE_SHIFT;
 	struct iov_iter to;
 	struct bio_vec bv = {.bv_page = page, .bv_len = PAGE_SIZE};
 
@@ -262,7 +262,6 @@ int orangefs_getattr(const struct path *path, struct kstat *stat,
 
 		/* override block size reported to stat */
 		orangefs_inode = ORANGEFS_I(inode);
-		stat->blksize = orangefs_inode->blksize;
 
 		if (request_mask & STATX_SIZE)
 			stat->result_mask = STATX_BASIC_STATS;
@@ -325,7 +324,6 @@ static int orangefs_init_iops(struct inode *inode)
 	case S_IFREG:
 		inode->i_op = &orangefs_file_inode_operations;
 		inode->i_fop = &orangefs_file_operations;
-		inode->i_blkbits = PAGE_SHIFT;
 		break;
 	case S_IFLNK:
 		inode->i_op = &orangefs_symlink_inode_operations;

fs/orangefs/orangefs-kernel.h

@@ -182,7 +182,6 @@ static inline void set_op_state_purged(struct orangefs_kernel_op_s *op)
 struct orangefs_inode_s {
 	struct orangefs_object_kref refn;
 	char link_target[ORANGEFS_NAME_MAX];
-	__s64 blksize;
 	/*
 	 * Reading/Writing Extended attributes need to acquire the appropriate
 	 * reader/writer semaphore on the orangefs_inode_s structure.

fs/orangefs/orangefs-utils.c

@@ -275,7 +275,7 @@ int orangefs_inode_getattr(struct inode *inode, int new, int bypass,
 {
 	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
 	struct orangefs_kernel_op_s *new_op;
-	loff_t inode_size, rounded_up_size;
+	loff_t inode_size;
 	int ret, type;
 
 	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: called on inode %pU\n", __func__,
@@ -330,22 +330,19 @@ int orangefs_inode_getattr(struct inode *inode, int new, int bypass,
 		if (request_mask & STATX_SIZE || new) {
 			inode_size = (loff_t)new_op->
 			    downcall.resp.getattr.attributes.size;
-			rounded_up_size =
-			    (inode_size + (4096 - (inode_size % 4096)));
 			inode->i_size = inode_size;
-			orangefs_inode->blksize =
-			    new_op->downcall.resp.getattr.attributes.blksize;
+			inode->i_blkbits = ffs(new_op->downcall.resp.getattr.
+			    attributes.blksize);
 			spin_lock(&inode->i_lock);
 			inode->i_bytes = inode_size;
 			inode->i_blocks =
-			    (unsigned long)(rounded_up_size / 512);
+			    (inode_size + 512 - inode_size % 512)/512;
 			spin_unlock(&inode->i_lock);
 		}
 		break;
 	case S_IFDIR:
 		if (request_mask & STATX_SIZE || new) {
 			inode->i_size = PAGE_SIZE;
-			orangefs_inode->blksize = i_blocksize(inode);
 			spin_lock(&inode->i_lock);
 			inode_set_bytes(inode, inode->i_size);
 			spin_unlock(&inode->i_lock);
@@ -356,7 +353,6 @@ int orangefs_inode_getattr(struct inode *inode, int new, int bypass,
 		if (new) {
 			inode->i_size = (loff_t)strlen(new_op->
 			    downcall.resp.getattr.link_target);
-			orangefs_inode->blksize = i_blocksize(inode);
 			ret = strscpy(orangefs_inode->link_target,
 			    new_op->downcall.resp.getattr.link_target,
 			    ORANGEFS_NAME_MAX);

fs/orangefs/super.c

@@ -423,8 +423,8 @@ static int orangefs_fill_sb(struct super_block *sb,
 	sb->s_op = &orangefs_s_ops;
 	sb->s_d_op = &orangefs_dentry_operations;
 
-	sb->s_blocksize = orangefs_bufmap_size_query();
-	sb->s_blocksize_bits = orangefs_bufmap_shift_query();
+	sb->s_blocksize = PAGE_SIZE;
+	sb->s_blocksize_bits = PAGE_SHIFT;
 	sb->s_maxbytes = MAX_LFS_FILESIZE;
 
 	root_object.khandle = ORANGEFS_SB(sb)->root_khandle;