Commit 63a4681f authored by David Howells's avatar David Howells
Browse files

afs: Locally edit directory data for mkdir/create/unlink/... 



Locally edit the contents of an AFS directory upon a successful inode
operation that modifies that directory (such as mkdir, create and unlink)
so that we can avoid the current practice of re-downloading the directory
after each change.

This is viable provided that the directory version number we get back from
the modifying RPC op is exactly incremented by 1 from what we had
previously.  The data in the directory contents is in a defined format that
we have to parse locally to perform lookups and readdir, so modifying isn't
a problem.

If the edit fails, we just clear the VALID flag on the directory and it
will be reloaded next time it is needed.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
parent 00317636

fs/afs/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ kafs-objs := \ 
	cell.o \

	cmservice.o \

	dir.o \

	dir_edit.o \

	dynroot.o \

	file.o \

	flock.o \

fs/afs/dir.c

+74 −9
Original line number Diff line number Diff line
@@ -130,17 +130,26 @@ static bool afs_dir_check_page(struct afs_vnode *dvnode, struct page *page, 
	qty /= sizeof(union afs_xdr_dir_block);



	/* check them */

	dbuf = page_address(page);

	dbuf = kmap(page);

	for (tmp = 0; tmp < qty; tmp++) {

		if (dbuf->blocks[tmp].hdr.magic != AFS_DIR_MAGIC) {

			printk("kAFS: %s(%lx): bad magic %d/%d is %04hx\n",

			       __func__, dvnode->vfs_inode.i_ino, tmp, qty,

			       ntohs(dbuf->blocks[tmp].hdr.magic));

			trace_afs_dir_check_failed(dvnode, off, i_size);

			kunmap(page);

			goto error;

		}



		/* Make sure each block is NUL terminated so we can reasonably

		 * use string functions on it.  The filenames in the page

		 * *should* be NUL-terminated anyway.

		 */

		((u8 *)&dbuf->blocks[tmp])[AFS_DIR_BLOCK_SIZE - 1] = 0;

	}



	kunmap(page);



checked:

	afs_stat_v(dvnode, n_read_dir);

	return true;
@@ -1114,6 +1123,7 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 
	struct afs_vnode *dvnode = AFS_FS_I(dir);

	struct afs_fid newfid;

	struct key *key;

	u64 data_version = dvnode->status.data_version;

	int ret;



	mode |= S_IFDIR;
@@ -1131,7 +1141,7 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 
	if (afs_begin_vnode_operation(&fc, dvnode, key)) {

		while (afs_select_fileserver(&fc)) {

			fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;

			afs_fs_create(&fc, dentry->d_name.name, mode,

			afs_fs_create(&fc, dentry->d_name.name, mode, data_version,

				      &newfid, &newstatus, &newcb);

		}
@@ -1145,6 +1155,11 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 
		goto error_key;

	}



	if (ret == 0 &&

	    test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))

		afs_edit_dir_add(dvnode, &dentry->d_name, &newfid,

				 afs_edit_dir_for_create);



	key_put(key);

	_leave(" = 0");

	return 0;
@@ -1168,6 +1183,7 @@ static void afs_dir_remove_subdir(struct dentry *dentry) 
		clear_nlink(&vnode->vfs_inode);

		set_bit(AFS_VNODE_DELETED, &vnode->flags);

		clear_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);

		clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

	}

}
@@ -1179,6 +1195,7 @@ static int afs_rmdir(struct inode *dir, struct dentry *dentry) 
	struct afs_fs_cursor fc;

	struct afs_vnode *dvnode = AFS_FS_I(dir);

	struct key *key;

	u64 data_version = dvnode->status.data_version;

	int ret;



	_enter("{%x:%u},{%pd}",
@@ -1194,13 +1211,18 @@ static int afs_rmdir(struct inode *dir, struct dentry *dentry) 
	if (afs_begin_vnode_operation(&fc, dvnode, key)) {

		while (afs_select_fileserver(&fc)) {

			fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;

			afs_fs_remove(&fc, dentry->d_name.name, true);

			afs_fs_remove(&fc, dentry->d_name.name, true,

				      data_version);

		}



		afs_vnode_commit_status(&fc, dvnode, fc.cb_break);

		ret = afs_end_vnode_operation(&fc);

		if (ret == 0)

		if (ret == 0) {

			afs_dir_remove_subdir(dentry);

			if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))

				afs_edit_dir_remove(dvnode, &dentry->d_name,

						    afs_edit_dir_for_rmdir);

		}

	}



	key_put(key);
@@ -1265,6 +1287,7 @@ static int afs_unlink(struct inode *dir, struct dentry *dentry) 
	struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode;

	struct key *key;

	unsigned long d_version = (unsigned long)dentry->d_fsdata;

	u64 data_version = dvnode->status.data_version;

	int ret;



	_enter("{%x:%u},{%pd}",
@@ -1291,7 +1314,8 @@ static int afs_unlink(struct inode *dir, struct dentry *dentry) 
	if (afs_begin_vnode_operation(&fc, dvnode, key)) {

		while (afs_select_fileserver(&fc)) {

			fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;

			afs_fs_remove(&fc, dentry->d_name.name, false);

			afs_fs_remove(&fc, dentry->d_name.name, false,

				      data_version);

		}



		afs_vnode_commit_status(&fc, dvnode, fc.cb_break);
@@ -1300,6 +1324,10 @@ static int afs_unlink(struct inode *dir, struct dentry *dentry) 
			ret = afs_dir_remove_link(

				dentry, key, d_version,

				(unsigned long)dvnode->status.data_version);

		if (ret == 0 &&

		    test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))

			afs_edit_dir_remove(dvnode, &dentry->d_name,

					    afs_edit_dir_for_unlink);

	}



error_key:
@@ -1321,6 +1349,7 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode, 
	struct afs_vnode *dvnode = AFS_FS_I(dir);

	struct afs_fid newfid;

	struct key *key;

	u64 data_version = dvnode->status.data_version;

	int ret;



	mode |= S_IFREG;
@@ -1342,7 +1371,7 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode, 
	if (afs_begin_vnode_operation(&fc, dvnode, key)) {

		while (afs_select_fileserver(&fc)) {

			fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;

			afs_fs_create(&fc, dentry->d_name.name, mode,

			afs_fs_create(&fc, dentry->d_name.name, mode, data_version,

				      &newfid, &newstatus, &newcb);

		}
@@ -1356,6 +1385,10 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode, 
		goto error_key;

	}



	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))

		afs_edit_dir_add(dvnode, &dentry->d_name, &newfid,

				 afs_edit_dir_for_create);



	key_put(key);

	_leave(" = 0");

	return 0;
@@ -1377,10 +1410,12 @@ static int afs_link(struct dentry *from, struct inode *dir, 
	struct afs_fs_cursor fc;

	struct afs_vnode *dvnode, *vnode;

	struct key *key;

	u64 data_version;

	int ret;



	vnode = AFS_FS_I(d_inode(from));

	dvnode = AFS_FS_I(dir);

	data_version = dvnode->status.data_version;



	_enter("{%x:%u},{%x:%u},{%pd}",

	       vnode->fid.vid, vnode->fid.vnode,
@@ -1407,7 +1442,7 @@ static int afs_link(struct dentry *from, struct inode *dir, 
		while (afs_select_fileserver(&fc)) {

			fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;

			fc.cb_break_2 = vnode->cb_break + vnode->cb_s_break;

			afs_fs_link(&fc, vnode, dentry->d_name.name);

			afs_fs_link(&fc, vnode, dentry->d_name.name, data_version);

		}



		afs_vnode_commit_status(&fc, dvnode, fc.cb_break);
@@ -1423,6 +1458,10 @@ static int afs_link(struct dentry *from, struct inode *dir, 
		goto error_key;

	}



	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))

		afs_edit_dir_add(dvnode, &dentry->d_name, &vnode->fid,

				 afs_edit_dir_for_link);



	key_put(key);

	_leave(" = 0");

	return 0;
@@ -1446,6 +1485,7 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry, 
	struct afs_vnode *dvnode = AFS_FS_I(dir);

	struct afs_fid newfid;

	struct key *key;

	u64 data_version = dvnode->status.data_version;

	int ret;



	_enter("{%x:%u},{%pd},%s",
@@ -1470,7 +1510,8 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry, 
	if (afs_begin_vnode_operation(&fc, dvnode, key)) {

		while (afs_select_fileserver(&fc)) {

			fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;

			afs_fs_symlink(&fc, dentry->d_name.name, content,

			afs_fs_symlink(&fc, dentry->d_name.name,

				       content, data_version,

				       &newfid, &newstatus);

		}
@@ -1484,6 +1525,10 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry, 
		goto error_key;

	}



	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))

		afs_edit_dir_add(dvnode, &dentry->d_name, &newfid,

				 afs_edit_dir_for_symlink);



	key_put(key);

	_leave(" = 0");

	return 0;
@@ -1506,6 +1551,8 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, 
	struct afs_fs_cursor fc;

	struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;

	struct key *key;

	u64 orig_data_version, new_data_version;

	bool new_negative = d_is_negative(new_dentry);

	int ret;



	if (flags)
@@ -1514,6 +1561,8 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, 
	vnode = AFS_FS_I(d_inode(old_dentry));

	orig_dvnode = AFS_FS_I(old_dir);

	new_dvnode = AFS_FS_I(new_dir);

	orig_data_version = orig_dvnode->status.data_version;

	new_data_version = new_dvnode->status.data_version;



	_enter("{%x:%u},{%x:%u},{%x:%u},{%pd}",

	       orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
@@ -1539,7 +1588,8 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, 
			fc.cb_break = orig_dvnode->cb_break + orig_dvnode->cb_s_break;

			fc.cb_break_2 = new_dvnode->cb_break + new_dvnode->cb_s_break;

			afs_fs_rename(&fc, old_dentry->d_name.name,

				      new_dvnode, new_dentry->d_name.name);

				      new_dvnode, new_dentry->d_name.name,

				      orig_data_version, new_data_version);

		}



		afs_vnode_commit_status(&fc, orig_dvnode, fc.cb_break);
@@ -1551,6 +1601,21 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, 
			goto error_key;

	}



	if (ret == 0) {

		if (test_bit(AFS_VNODE_DIR_VALID, &orig_dvnode->flags))

		    afs_edit_dir_remove(orig_dvnode, &old_dentry->d_name,

					afs_edit_dir_for_rename);



		if (!new_negative &&

		    test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags))

			afs_edit_dir_remove(new_dvnode, &new_dentry->d_name,

					    afs_edit_dir_for_rename);



		if (test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags))

			afs_edit_dir_add(new_dvnode, &new_dentry->d_name,

					 &vnode->fid,  afs_edit_dir_for_rename);

	}



error_key:

	key_put(key);

error:

fs/afs/dir_edit.c

0 → 100644
+505 −0
Original line number Diff line number Diff line 
/* AFS filesystem directory editing

 *

 * Copyright (C) 2018 Red Hat, Inc. All Rights Reserved.

 * Written by David Howells (dhowells@redhat.com)

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public Licence

 * as published by the Free Software Foundation; either version

 * 2 of the Licence, or (at your option) any later version.

 */



#include <linux/kernel.h>

#include <linux/fs.h>

#include <linux/namei.h>

#include <linux/pagemap.h>

#include <linux/iversion.h>

#include "internal.h"

#include "xdr_fs.h"



/*

 * Find a number of contiguous clear bits in a directory block bitmask.

 *

 * There are 64 slots, which means we can load the entire bitmap into a

 * variable.  The first bit doesn't count as it corresponds to the block header

 * slot.  nr_slots is between 1 and 9.

 */

static int afs_find_contig_bits(union afs_xdr_dir_block *block, unsigned int nr_slots)

{

	u64 bitmap;

	u32 mask;

	int bit, n;



	bitmap  = (u64)block->hdr.bitmap[0] << 0 * 8;

	bitmap |= (u64)block->hdr.bitmap[1] << 1 * 8;

	bitmap |= (u64)block->hdr.bitmap[2] << 2 * 8;

	bitmap |= (u64)block->hdr.bitmap[3] << 3 * 8;

	bitmap |= (u64)block->hdr.bitmap[4] << 4 * 8;

	bitmap |= (u64)block->hdr.bitmap[5] << 5 * 8;

	bitmap |= (u64)block->hdr.bitmap[6] << 6 * 8;

	bitmap |= (u64)block->hdr.bitmap[7] << 7 * 8;

	bitmap >>= 1; /* The first entry is metadata */

	bit = 1;

	mask = (1 << nr_slots) - 1;



	do {

		if (sizeof(unsigned long) == 8)

			n = ffz(bitmap);

		else

			n = ((u32)bitmap) != 0 ?

				ffz((u32)bitmap) :

				ffz((u32)(bitmap >> 32)) + 32;

		bitmap >>= n;

		bit += n;



		if ((bitmap & mask) == 0) {

			if (bit > 64 - nr_slots)

				return -1;

			return bit;

		}



		n = __ffs(bitmap);

		bitmap >>= n;

		bit += n;

	} while (bitmap);



	return -1;

}



/*

 * Set a number of contiguous bits in the directory block bitmap.

 */

static void afs_set_contig_bits(union afs_xdr_dir_block *block,

				int bit, unsigned int nr_slots)

{

	u64 mask, before, after;



	mask = (1 << nr_slots) - 1;

	mask <<= bit;



	before = *(u64 *)block->hdr.bitmap;



	block->hdr.bitmap[0] |= (u8)(mask >> 0 * 8);

	block->hdr.bitmap[1] |= (u8)(mask >> 1 * 8);

	block->hdr.bitmap[2] |= (u8)(mask >> 2 * 8);

	block->hdr.bitmap[3] |= (u8)(mask >> 3 * 8);

	block->hdr.bitmap[4] |= (u8)(mask >> 4 * 8);

	block->hdr.bitmap[5] |= (u8)(mask >> 5 * 8);

	block->hdr.bitmap[6] |= (u8)(mask >> 6 * 8);

	block->hdr.bitmap[7] |= (u8)(mask >> 7 * 8);



	after = *(u64 *)block->hdr.bitmap;

}



/*

 * Clear a number of contiguous bits in the directory block bitmap.

 */

static void afs_clear_contig_bits(union afs_xdr_dir_block *block,

				  int bit, unsigned int nr_slots)

{

	u64 mask, before, after;



	mask = (1 << nr_slots) - 1;

	mask <<= bit;



	before = *(u64 *)block->hdr.bitmap;



	block->hdr.bitmap[0] &= ~(u8)(mask >> 0 * 8);

	block->hdr.bitmap[1] &= ~(u8)(mask >> 1 * 8);

	block->hdr.bitmap[2] &= ~(u8)(mask >> 2 * 8);

	block->hdr.bitmap[3] &= ~(u8)(mask >> 3 * 8);

	block->hdr.bitmap[4] &= ~(u8)(mask >> 4 * 8);

	block->hdr.bitmap[5] &= ~(u8)(mask >> 5 * 8);

	block->hdr.bitmap[6] &= ~(u8)(mask >> 6 * 8);

	block->hdr.bitmap[7] &= ~(u8)(mask >> 7 * 8);



	after = *(u64 *)block->hdr.bitmap;

}



/*

 * Scan a directory block looking for a dirent of the right name.

 */

static int afs_dir_scan_block(union afs_xdr_dir_block *block, struct qstr *name,

			      unsigned int blocknum)

{

	union afs_xdr_dirent *de;

	u64 bitmap;

	int d, len, n;



	_enter("");



	bitmap  = (u64)block->hdr.bitmap[0] << 0 * 8;

	bitmap |= (u64)block->hdr.bitmap[1] << 1 * 8;

	bitmap |= (u64)block->hdr.bitmap[2] << 2 * 8;

	bitmap |= (u64)block->hdr.bitmap[3] << 3 * 8;

	bitmap |= (u64)block->hdr.bitmap[4] << 4 * 8;

	bitmap |= (u64)block->hdr.bitmap[5] << 5 * 8;

	bitmap |= (u64)block->hdr.bitmap[6] << 6 * 8;

	bitmap |= (u64)block->hdr.bitmap[7] << 7 * 8;



	for (d = (blocknum == 0 ? AFS_DIR_RESV_BLOCKS0 : AFS_DIR_RESV_BLOCKS);

	     d < AFS_DIR_SLOTS_PER_BLOCK;

	     d++) {

		if (!((bitmap >> d) & 1))

			continue;

		de = &block->dirents[d];

		if (de->u.valid != 1)

			continue;



		/* The block was NUL-terminated by afs_dir_check_page(). */

		len = strlen(de->u.name);

		if (len == name->len &&

		    memcmp(de->u.name, name->name, name->len) == 0)

			return d;



		n = round_up(12 + len + 1 + 4, AFS_DIR_DIRENT_SIZE);

		n /= AFS_DIR_DIRENT_SIZE;

		d += n - 1;

	}



	return -1;

}



/*

 * Initialise a new directory block.  Note that block 0 is special and contains

 * some extra metadata.

 */

static void afs_edit_init_block(union afs_xdr_dir_block *meta,

				union afs_xdr_dir_block *block, int block_num)

{

	memset(block, 0, sizeof(*block));

	block->hdr.npages = htons(1);

	block->hdr.magic = AFS_DIR_MAGIC;

	block->hdr.bitmap[0] = 1;



	if (block_num == 0) {

		block->hdr.bitmap[0] = 0xff;

		block->hdr.bitmap[1] = 0x1f;

		memset(block->meta.alloc_ctrs,

		       AFS_DIR_SLOTS_PER_BLOCK,

		       sizeof(block->meta.alloc_ctrs));

		meta->meta.alloc_ctrs[0] =

			AFS_DIR_SLOTS_PER_BLOCK - AFS_DIR_RESV_BLOCKS0;

	}



	if (block_num < AFS_DIR_BLOCKS_WITH_CTR)

		meta->meta.alloc_ctrs[block_num] =

			AFS_DIR_SLOTS_PER_BLOCK - AFS_DIR_RESV_BLOCKS;

}



/*

 * Edit a directory's file data to add a new directory entry.  Doing this after

 * create, mkdir, symlink, link or rename if the data version number is

 * incremented by exactly one avoids the need to re-download the entire

 * directory contents.

 *

 * The caller must hold the inode locked.

 */

void afs_edit_dir_add(struct afs_vnode *vnode,

		      struct qstr *name, struct afs_fid *new_fid,

		      enum afs_edit_dir_reason why)

{

	union afs_xdr_dir_block *meta, *block;

	struct afs_xdr_dir_page *meta_page, *dir_page;

	union afs_xdr_dirent *de;

	struct page *page0, *page;

	unsigned int need_slots, nr_blocks, b;

	pgoff_t index;

	loff_t i_size;

	gfp_t gfp;

	int slot;



	_enter(",,{%d,%s},", name->len, name->name);



	i_size = i_size_read(&vnode->vfs_inode);

	if (i_size > AFS_DIR_BLOCK_SIZE * AFS_DIR_MAX_BLOCKS ||

	    (i_size & (AFS_DIR_BLOCK_SIZE - 1))) {

		clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

		return;

	}



	gfp = vnode->vfs_inode.i_mapping->gfp_mask;

	page0 = find_or_create_page(vnode->vfs_inode.i_mapping, 0, gfp);

	if (!page0) {

		clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

		_leave(" [fgp]");

		return;

	}



	/* Work out how many slots we're going to need. */

	need_slots = round_up(12 + name->len + 1 + 4, AFS_DIR_DIRENT_SIZE);

	need_slots /= AFS_DIR_DIRENT_SIZE;



	meta_page = kmap(page0);

	meta = &meta_page->blocks[0];

	if (i_size == 0)

		goto new_directory;

	nr_blocks = i_size / AFS_DIR_BLOCK_SIZE;



	/* Find a block that has sufficient slots available.  Each VM page

	 * contains two or more directory blocks.

	 */

	for (b = 0; b < nr_blocks + 1; b++) {

		/* If the directory extended into a new page, then we need to

		 * tack a new page on the end.

		 */

		index = b / AFS_DIR_BLOCKS_PER_PAGE;

		if (index == 0) {

			page = page0;

			dir_page = meta_page;

		} else {

			if (nr_blocks >= AFS_DIR_MAX_BLOCKS)

				goto error;

			gfp = vnode->vfs_inode.i_mapping->gfp_mask;

			page = find_or_create_page(vnode->vfs_inode.i_mapping,

						   index, gfp);

			if (!page)

				goto error;

			if (!PagePrivate(page)) {

				set_page_private(page, 1);

				SetPagePrivate(page);

			}

			dir_page = kmap(page);

		}



		/* Abandon the edit if we got a callback break. */

		if (!test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))

			goto invalidated;



		block = &dir_page->blocks[b % AFS_DIR_BLOCKS_PER_PAGE];



		_debug("block %u: %2u %3u %u",

		       b,

		       (b < AFS_DIR_BLOCKS_WITH_CTR) ? meta->meta.alloc_ctrs[b] : 99,

		       ntohs(block->hdr.npages),

		       ntohs(block->hdr.magic));



		/* Initialise the block if necessary. */

		if (b == nr_blocks) {

			_debug("init %u", b);

			afs_edit_init_block(meta, block, b);

			i_size_write(&vnode->vfs_inode, (b + 1) * AFS_DIR_BLOCK_SIZE);

		}



		/* Only lower dir pages have a counter in the header. */

		if (b >= AFS_DIR_BLOCKS_WITH_CTR ||

		    meta->meta.alloc_ctrs[b] >= need_slots) {

			/* We need to try and find one or more consecutive

			 * slots to hold the entry.

			 */

			slot = afs_find_contig_bits(block, need_slots);

			if (slot >= 0) {

				_debug("slot %u", slot);

				goto found_space;

			}

		}



		if (page != page0) {

			unlock_page(page);

			kunmap(page);

			put_page(page);

		}

	}



	/* There are no spare slots of sufficient size, yet the operation

	 * succeeded.  Download the directory again.

	 */

	trace_afs_edit_dir(vnode, why, afs_edit_dir_create_nospc, 0, 0, 0, 0, name->name);

	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

	goto out_unmap;



new_directory:

	afs_edit_init_block(meta, meta, 0);

	i_size = AFS_DIR_BLOCK_SIZE;

	i_size_write(&vnode->vfs_inode, i_size);

	slot = AFS_DIR_RESV_BLOCKS0;

	page = page0;

	block = meta;

	nr_blocks = 1;

	b = 0;



found_space:

	/* Set the dirent slot. */

	trace_afs_edit_dir(vnode, why, afs_edit_dir_create, b, slot,

			   new_fid->vnode, new_fid->unique, name->name);

	de = &block->dirents[slot];

	de->u.valid	= 1;

	de->u.unused[0]	= 0;

	de->u.hash_next	= 0; // TODO: Really need to maintain this

	de->u.vnode	= htonl(new_fid->vnode);

	de->u.unique	= htonl(new_fid->unique);

	memcpy(de->u.name, name->name, name->len + 1);

	de->u.name[name->len] = 0;



	/* Adjust the bitmap. */

	afs_set_contig_bits(block, slot, need_slots);

	if (page != page0) {

		unlock_page(page);

		kunmap(page);

		put_page(page);

	}



	/* Adjust the allocation counter. */

	if (b < AFS_DIR_BLOCKS_WITH_CTR)

		meta->meta.alloc_ctrs[b] -= need_slots;



	inode_inc_iversion_raw(&vnode->vfs_inode);

	afs_stat_v(vnode, n_dir_cr);

	_debug("Insert %s in %u[%u]", name->name, b, slot);



out_unmap:

	unlock_page(page0);

	kunmap(page0);

	put_page(page0);

	_leave("");

	return;



invalidated:

	trace_afs_edit_dir(vnode, why, afs_edit_dir_create_inval, 0, 0, 0, 0, name->name);

	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

	if (page != page0) {

		kunmap(page);

		put_page(page);

	}

	goto out_unmap;



error:

	trace_afs_edit_dir(vnode, why, afs_edit_dir_create_error, 0, 0, 0, 0, name->name);

	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

	goto out_unmap;

}



/*

 * Edit a directory's file data to remove a new directory entry.  Doing this

 * after unlink, rmdir or rename if the data version number is incremented by

 * exactly one avoids the need to re-download the entire directory contents.

 *

 * The caller must hold the inode locked.

 */

void afs_edit_dir_remove(struct afs_vnode *vnode,

			 struct qstr *name, enum afs_edit_dir_reason why)

{

	struct afs_xdr_dir_page *meta_page, *dir_page;

	union afs_xdr_dir_block *meta, *block;

	union afs_xdr_dirent *de;

	struct page *page0, *page;

	unsigned int need_slots, nr_blocks, b;

	pgoff_t index;

	loff_t i_size;

	int slot;



	_enter(",,{%d,%s},", name->len, name->name);



	i_size = i_size_read(&vnode->vfs_inode);

	if (i_size < AFS_DIR_BLOCK_SIZE ||

	    i_size > AFS_DIR_BLOCK_SIZE * AFS_DIR_MAX_BLOCKS ||

	    (i_size & (AFS_DIR_BLOCK_SIZE - 1))) {

		clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

		return;

	}

	nr_blocks = i_size / AFS_DIR_BLOCK_SIZE;



	page0 = find_lock_page(vnode->vfs_inode.i_mapping, 0);

	if (!page0) {

		clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

		_leave(" [fgp]");

		return;

	}



	/* Work out how many slots we're going to discard. */

	need_slots = round_up(12 + name->len + 1 + 4, AFS_DIR_DIRENT_SIZE);

	need_slots /= AFS_DIR_DIRENT_SIZE;



	meta_page = kmap(page0);

	meta = &meta_page->blocks[0];



	/* Find a page that has sufficient slots available.  Each VM page

	 * contains two or more directory blocks.

	 */

	for (b = 0; b < nr_blocks; b++) {

		index = b / AFS_DIR_BLOCKS_PER_PAGE;

		if (index != 0) {

			page = find_lock_page(vnode->vfs_inode.i_mapping, index);

			if (!page)

				goto error;

			dir_page = kmap(page);

		} else {

			page = page0;

			dir_page = meta_page;

		}



		/* Abandon the edit if we got a callback break. */

		if (!test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))

			goto invalidated;



		block = &dir_page->blocks[b % AFS_DIR_BLOCKS_PER_PAGE];



		if (b > AFS_DIR_BLOCKS_WITH_CTR ||

		    meta->meta.alloc_ctrs[b] <= AFS_DIR_SLOTS_PER_BLOCK - 1 - need_slots) {

			slot = afs_dir_scan_block(block, name, b);

			if (slot >= 0)

				goto found_dirent;

		}



		if (page != page0) {

			unlock_page(page);

			kunmap(page);

			put_page(page);

		}

	}



	/* Didn't find the dirent to clobber.  Download the directory again. */

	trace_afs_edit_dir(vnode, why, afs_edit_dir_delete_noent,

			   0, 0, 0, 0, name->name);

	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

	goto out_unmap;



found_dirent:

	de = &block->dirents[slot];



	trace_afs_edit_dir(vnode, why, afs_edit_dir_delete, b, slot,

			   ntohl(de->u.vnode), ntohl(de->u.unique),

			   name->name);



	memset(de, 0, sizeof(*de) * need_slots);



	/* Adjust the bitmap. */

	afs_clear_contig_bits(block, slot, need_slots);

	if (page != page0) {

		unlock_page(page);

		kunmap(page);

		put_page(page);

	}



	/* Adjust the allocation counter. */

	if (b < AFS_DIR_BLOCKS_WITH_CTR)

		meta->meta.alloc_ctrs[b] += need_slots;



	inode_set_iversion_raw(&vnode->vfs_inode, vnode->status.data_version);

	afs_stat_v(vnode, n_dir_rm);

	_debug("Remove %s from %u[%u]", name->name, b, slot);



out_unmap:

	unlock_page(page0);

	kunmap(page0);

	put_page(page0);

	_leave("");

	return;



invalidated:

	trace_afs_edit_dir(vnode, why, afs_edit_dir_delete_inval,

			   0, 0, 0, 0, name->name);

	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

	if (page != page0) {

		unlock_page(page);

		kunmap(page);

		put_page(page);

	}

	goto out_unmap;



error:

	trace_afs_edit_dir(vnode, why, afs_edit_dir_delete_error,

			   0, 0, 0, 0, name->name);

	clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);

	goto out_unmap;

}

fs/afs/fsclient.c

+22 −13
Original line number Diff line number Diff line
@@ -107,6 +107,13 @@ void afs_update_inode_from_status(struct afs_vnode *vnode, 
			} else {

				set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);

			}

		} else if (vnode->status.type == AFS_FTYPE_DIR) {

			/* Expected directory change is handled elsewhere so

			 * that we can locally edit the directory and save on a

			 * download.

			 */

			if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))

				flags &= ~AFS_VNODE_DATA_CHANGED;

		}

	}
@@ -190,10 +197,7 @@ static int xdr_decode_AFSFetchStatus(const __be32 **_bp, 


	size  = (u64)ntohl(xdr->size_lo);

	size |= (u64)ntohl(xdr->size_hi) << 32;

	if (size != status->size) {

	status->size = size;

		flags |= AFS_VNODE_DATA_CHANGED;

	}



	data_version  = (u64)ntohl(xdr->data_version_lo);

	data_version |= (u64)ntohl(xdr->data_version_hi) << 32;
@@ -736,6 +740,7 @@ static const struct afs_call_type afs_RXFSMakeDir = { 
int afs_fs_create(struct afs_fs_cursor *fc,

		  const char *name,

		  umode_t mode,

		  u64 current_data_version,

		  struct afs_fid *newfid,

		  struct afs_file_status *newstatus,

		  struct afs_callback *newcb)
@@ -763,7 +768,7 @@ int afs_fs_create(struct afs_fs_cursor *fc, 
	call->reply[1] = newfid;

	call->reply[2] = newstatus;

	call->reply[3] = newcb;

	call->expected_version = vnode->status.data_version;

	call->expected_version = current_data_version + 1;



	/* marshall the parameters */

	bp = call->request;
@@ -836,7 +841,8 @@ static const struct afs_call_type afs_RXFSRemoveDir = { 
/*

 * remove a file or directory

 */

int afs_fs_remove(struct afs_fs_cursor *fc, const char *name, bool isdir)

int afs_fs_remove(struct afs_fs_cursor *fc, const char *name, bool isdir,

		  u64 current_data_version)

{

	struct afs_vnode *vnode = fc->vnode;

	struct afs_call *call;
@@ -858,7 +864,7 @@ int afs_fs_remove(struct afs_fs_cursor *fc, const char *name, bool isdir) 


	call->key = fc->key;

	call->reply[0] = vnode;

	call->expected_version = vnode->status.data_version;

	call->expected_version = current_data_version + 1;



	/* marshall the parameters */

	bp = call->request;
@@ -920,7 +926,7 @@ static const struct afs_call_type afs_RXFSLink = { 
 * make a hard link

 */

int afs_fs_link(struct afs_fs_cursor *fc, struct afs_vnode *vnode,

		const char *name)

		const char *name, u64 current_data_version)

{

	struct afs_vnode *dvnode = fc->vnode;

	struct afs_call *call;
@@ -941,7 +947,7 @@ int afs_fs_link(struct afs_fs_cursor *fc, struct afs_vnode *vnode, 
	call->key = fc->key;

	call->reply[0] = dvnode;

	call->reply[1] = vnode;

	call->expected_version = vnode->status.data_version;

	call->expected_version = current_data_version + 1;



	/* marshall the parameters */

	bp = call->request;
@@ -1009,6 +1015,7 @@ static const struct afs_call_type afs_RXFSSymlink = { 
int afs_fs_symlink(struct afs_fs_cursor *fc,

		   const char *name,

		   const char *contents,

		   u64 current_data_version,

		   struct afs_fid *newfid,

		   struct afs_file_status *newstatus)

{
@@ -1037,7 +1044,7 @@ int afs_fs_symlink(struct afs_fs_cursor *fc, 
	call->reply[0] = vnode;

	call->reply[1] = newfid;

	call->reply[2] = newstatus;

	call->expected_version = vnode->status.data_version;

	call->expected_version = current_data_version + 1;



	/* marshall the parameters */

	bp = call->request;
@@ -1117,7 +1124,9 @@ static const struct afs_call_type afs_RXFSRename = { 
int afs_fs_rename(struct afs_fs_cursor *fc,

		  const char *orig_name,

		  struct afs_vnode *new_dvnode,

		  const char *new_name)

		  const char *new_name,

		  u64 current_orig_data_version,

		  u64 current_new_data_version)

{

	struct afs_vnode *orig_dvnode = fc->vnode;

	struct afs_call *call;
@@ -1145,8 +1154,8 @@ int afs_fs_rename(struct afs_fs_cursor *fc, 
	call->key = fc->key;

	call->reply[0] = orig_dvnode;

	call->reply[1] = new_dvnode;

	call->expected_version = orig_dvnode->status.data_version;

	call->expected_version_2 = new_dvnode->status.data_version;

	call->expected_version = current_orig_data_version + 1;

	call->expected_version_2 = current_new_data_version + 1;



	/* marshall the parameters */

	bp = call->request;

fs/afs/inode.c

+5 −2
Original line number Diff line number Diff line
@@ -395,8 +395,11 @@ int afs_validate(struct afs_vnode *vnode, struct key *key) 
	if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {

		if (vnode->cb_s_break != vnode->cb_interest->server->cb_s_break) {

			vnode->cb_s_break = vnode->cb_interest->server->cb_s_break;

		} else if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags) &&

			   !test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags) &&

		} else if (vnode->status.type == AFS_FTYPE_DIR &&

			   test_bit(AFS_VNODE_DIR_VALID, &vnode->flags) &&

			   vnode->cb_expires_at - 10 > now) {

				valid = true;

		} else if (!test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags) &&

			   vnode->cb_expires_at - 10 > now) {

				valid = true;

		}

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