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-rw-r--r--fs/aufs/dynop.c356
1 files changed, 0 insertions, 356 deletions
diff --git a/fs/aufs/dynop.c b/fs/aufs/dynop.c
deleted file mode 100644
index 53a8b55d8..000000000
--- a/fs/aufs/dynop.c
+++ /dev/null
@@ -1,356 +0,0 @@
-/*
- * Copyright (C) 2010-2016 Junjiro R. Okajima
- */
-
-/*
- * dynamically customizable operations for regular files
- */
-
-#include "aufs.h"
-
-#define DyPrSym(key) AuDbgSym(key->dk_op.dy_hop)
-
-/*
- * How large will these lists be?
- * Usually just a few elements, 20-30 at most for each, I guess.
- */
-static struct au_splhead dynop[AuDyLast];
-
-static struct au_dykey *dy_gfind_get(struct au_splhead *spl, const void *h_op)
-{
- struct au_dykey *key, *tmp;
- struct list_head *head;
-
- key = NULL;
- head = &spl->head;
- rcu_read_lock();
- list_for_each_entry_rcu(tmp, head, dk_list)
- if (tmp->dk_op.dy_hop == h_op) {
- key = tmp;
- kref_get(&key->dk_kref);
- break;
- }
- rcu_read_unlock();
-
- return key;
-}
-
-static struct au_dykey *dy_bradd(struct au_branch *br, struct au_dykey *key)
-{
- struct au_dykey **k, *found;
- const void *h_op = key->dk_op.dy_hop;
- int i;
-
- found = NULL;
- k = br->br_dykey;
- for (i = 0; i < AuBrDynOp; i++)
- if (k[i]) {
- if (k[i]->dk_op.dy_hop == h_op) {
- found = k[i];
- break;
- }
- } else
- break;
- if (!found) {
- spin_lock(&br->br_dykey_lock);
- for (; i < AuBrDynOp; i++)
- if (k[i]) {
- if (k[i]->dk_op.dy_hop == h_op) {
- found = k[i];
- break;
- }
- } else {
- k[i] = key;
- break;
- }
- spin_unlock(&br->br_dykey_lock);
- BUG_ON(i == AuBrDynOp); /* expand the array */
- }
-
- return found;
-}
-
-/* kref_get() if @key is already added */
-static struct au_dykey *dy_gadd(struct au_splhead *spl, struct au_dykey *key)
-{
- struct au_dykey *tmp, *found;
- struct list_head *head;
- const void *h_op = key->dk_op.dy_hop;
-
- found = NULL;
- head = &spl->head;
- spin_lock(&spl->spin);
- list_for_each_entry(tmp, head, dk_list)
- if (tmp->dk_op.dy_hop == h_op) {
- kref_get(&tmp->dk_kref);
- found = tmp;
- break;
- }
- if (!found)
- list_add_rcu(&key->dk_list, head);
- spin_unlock(&spl->spin);
-
- if (!found)
- DyPrSym(key);
- return found;
-}
-
-static void dy_free_rcu(struct rcu_head *rcu)
-{
- struct au_dykey *key;
-
- key = container_of(rcu, struct au_dykey, dk_rcu);
- DyPrSym(key);
- kfree(key);
-}
-
-static void dy_free(struct kref *kref)
-{
- struct au_dykey *key;
- struct au_splhead *spl;
-
- key = container_of(kref, struct au_dykey, dk_kref);
- spl = dynop + key->dk_op.dy_type;
- au_spl_del_rcu(&key->dk_list, spl);
- call_rcu(&key->dk_rcu, dy_free_rcu);
-}
-
-void au_dy_put(struct au_dykey *key)
-{
- kref_put(&key->dk_kref, dy_free);
-}
-
-/* ---------------------------------------------------------------------- */
-
-#define DyDbgSize(cnt, op) AuDebugOn(cnt != sizeof(op)/sizeof(void *))
-
-#ifdef CONFIG_AUFS_DEBUG
-#define DyDbgDeclare(cnt) unsigned int cnt = 0
-#define DyDbgInc(cnt) do { cnt++; } while (0)
-#else
-#define DyDbgDeclare(cnt) do {} while (0)
-#define DyDbgInc(cnt) do {} while (0)
-#endif
-
-#define DySet(func, dst, src, h_op, h_sb) do { \
- DyDbgInc(cnt); \
- if (h_op->func) { \
- if (src.func) \
- dst.func = src.func; \
- else \
- AuDbg("%s %s\n", au_sbtype(h_sb), #func); \
- } \
-} while (0)
-
-#define DySetForce(func, dst, src) do { \
- AuDebugOn(!src.func); \
- DyDbgInc(cnt); \
- dst.func = src.func; \
-} while (0)
-
-#define DySetAop(func) \
- DySet(func, dyaop->da_op, aufs_aop, h_aop, h_sb)
-#define DySetAopForce(func) \
- DySetForce(func, dyaop->da_op, aufs_aop)
-
-static void dy_aop(struct au_dykey *key, const void *h_op,
- struct super_block *h_sb __maybe_unused)
-{
- struct au_dyaop *dyaop = (void *)key;
- const struct address_space_operations *h_aop = h_op;
- DyDbgDeclare(cnt);
-
- AuDbg("%s\n", au_sbtype(h_sb));
-
- DySetAop(writepage);
- DySetAopForce(readpage); /* force */
- DySetAop(writepages);
- DySetAop(set_page_dirty);
- DySetAop(readpages);
- DySetAop(write_begin);
- DySetAop(write_end);
- DySetAop(bmap);
- DySetAop(invalidatepage);
- DySetAop(releasepage);
- DySetAop(freepage);
- /* this one will be changed according to an aufs mount option */
- DySetAop(direct_IO);
- DySetAop(migratepage);
- DySetAop(launder_page);
- DySetAop(is_partially_uptodate);
- DySetAop(is_dirty_writeback);
- DySetAop(error_remove_page);
- DySetAop(swap_activate);
- DySetAop(swap_deactivate);
-
- DyDbgSize(cnt, *h_aop);
-}
-
-/* ---------------------------------------------------------------------- */
-
-static void dy_bug(struct kref *kref)
-{
- BUG();
-}
-
-static struct au_dykey *dy_get(struct au_dynop *op, struct au_branch *br)
-{
- struct au_dykey *key, *old;
- struct au_splhead *spl;
- struct op {
- unsigned int sz;
- void (*set)(struct au_dykey *key, const void *h_op,
- struct super_block *h_sb __maybe_unused);
- };
- static const struct op a[] = {
- [AuDy_AOP] = {
- .sz = sizeof(struct au_dyaop),
- .set = dy_aop
- }
- };
- const struct op *p;
-
- spl = dynop + op->dy_type;
- key = dy_gfind_get(spl, op->dy_hop);
- if (key)
- goto out_add; /* success */
-
- p = a + op->dy_type;
- key = kzalloc(p->sz, GFP_NOFS);
- if (unlikely(!key)) {
- key = ERR_PTR(-ENOMEM);
- goto out;
- }
-
- key->dk_op.dy_hop = op->dy_hop;
- kref_init(&key->dk_kref);
- p->set(key, op->dy_hop, au_br_sb(br));
- old = dy_gadd(spl, key);
- if (old) {
- kfree(key);
- key = old;
- }
-
-out_add:
- old = dy_bradd(br, key);
- if (old)
- /* its ref-count should never be zero here */
- kref_put(&key->dk_kref, dy_bug);
-out:
- return key;
-}
-
-/* ---------------------------------------------------------------------- */
-/*
- * Aufs prohibits O_DIRECT by defaut even if the branch supports it.
- * This behaviour is necessary to return an error from open(O_DIRECT) instead
- * of the succeeding I/O. The dio mount option enables O_DIRECT and makes
- * open(O_DIRECT) always succeed, but the succeeding I/O may return an error.
- * See the aufs manual in detail.
- */
-static void dy_adx(struct au_dyaop *dyaop, int do_dx)
-{
- if (!do_dx)
- dyaop->da_op.direct_IO = NULL;
- else
- dyaop->da_op.direct_IO = aufs_aop.direct_IO;
-}
-
-static struct au_dyaop *dy_aget(struct au_branch *br,
- const struct address_space_operations *h_aop,
- int do_dx)
-{
- struct au_dyaop *dyaop;
- struct au_dynop op;
-
- op.dy_type = AuDy_AOP;
- op.dy_haop = h_aop;
- dyaop = (void *)dy_get(&op, br);
- if (IS_ERR(dyaop))
- goto out;
- dy_adx(dyaop, do_dx);
-
-out:
- return dyaop;
-}
-
-int au_dy_iaop(struct inode *inode, aufs_bindex_t bindex,
- struct inode *h_inode)
-{
- int err, do_dx;
- struct super_block *sb;
- struct au_branch *br;
- struct au_dyaop *dyaop;
-
- AuDebugOn(!S_ISREG(h_inode->i_mode));
- IiMustWriteLock(inode);
-
- sb = inode->i_sb;
- br = au_sbr(sb, bindex);
- do_dx = !!au_opt_test(au_mntflags(sb), DIO);
- dyaop = dy_aget(br, h_inode->i_mapping->a_ops, do_dx);
- err = PTR_ERR(dyaop);
- if (IS_ERR(dyaop))
- /* unnecessary to call dy_fput() */
- goto out;
-
- err = 0;
- inode->i_mapping->a_ops = &dyaop->da_op;
-
-out:
- return err;
-}
-
-/*
- * Is it safe to replace a_ops during the inode/file is in operation?
- * Yes, I hope so.
- */
-int au_dy_irefresh(struct inode *inode)
-{
- int err;
- aufs_bindex_t bstart;
- struct inode *h_inode;
-
- err = 0;
- if (S_ISREG(inode->i_mode)) {
- bstart = au_ibstart(inode);
- h_inode = au_h_iptr(inode, bstart);
- err = au_dy_iaop(inode, bstart, h_inode);
- }
- return err;
-}
-
-void au_dy_arefresh(int do_dx)
-{
- struct au_splhead *spl;
- struct list_head *head;
- struct au_dykey *key;
-
- spl = dynop + AuDy_AOP;
- head = &spl->head;
- spin_lock(&spl->spin);
- list_for_each_entry(key, head, dk_list)
- dy_adx((void *)key, do_dx);
- spin_unlock(&spl->spin);
-}
-
-/* ---------------------------------------------------------------------- */
-
-void __init au_dy_init(void)
-{
- int i;
-
- /* make sure that 'struct au_dykey *' can be any type */
- BUILD_BUG_ON(offsetof(struct au_dyaop, da_key));
-
- for (i = 0; i < AuDyLast; i++)
- au_spl_init(dynop + i);
-}
-
-void au_dy_fin(void)
-{
- int i;
-
- for (i = 0; i < AuDyLast; i++)
- WARN_ON(!list_empty(&dynop[i].head));
-}
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