1 files changed, 155 insertions, 85 deletions

diff --git a/ipc/shm.c b/ipc/shm.c
index 5bb617f..eb57e22 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -37,11 +37,21 @@
 #include <linux/seq_file.h>
 #include <linux/mutex.h>
 #include <linux/nsproxy.h>
+#include <linux/mount.h>
 
 #include <asm/uaccess.h>
 
 #include "util.h"
 
+struct shm_file_data {
+	int id;
+	struct ipc_namespace *ns;
+	struct file *file;
+	const struct vm_operations_struct *vm_ops;
+};
+
+#define shm_file_data(file) (*((struct shm_file_data **)&(file)->private_data))
+
 static const struct file_operations shm_file_operations;
 static struct vm_operations_struct shm_vm_ops;
 
@@ -60,8 +70,8 @@ static struct ipc_ids init_shm_ids;
 
 static int newseg (struct ipc_namespace *ns, key_t key,
 		int shmflg, size_t size);
-static void shm_open (struct vm_area_struct *shmd);
-static void shm_close (struct vm_area_struct *shmd);
+static void shm_open(struct vm_area_struct *vma);
+static void shm_close(struct vm_area_struct *vma);
 static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp);
 #ifdef CONFIG_PROC_FS
 static int sysvipc_shm_proc_show(struct seq_file *s, void *it);
@@ -150,11 +160,14 @@ static inline int shm_addid(struct ipc_namespace *ns, struct shmid_kernel *shp)
 
 
 
-static inline void shm_inc(struct ipc_namespace *ns, int id)
+/* This is called by fork, once for every shm attach. */
+static void shm_open(struct vm_area_struct *vma)
 {
+	struct file *file = vma->vm_file;
+	struct shm_file_data *sfd = shm_file_data(file);
 	struct shmid_kernel *shp;
 
-	shp = shm_lock(ns, id);
+	shp = shm_lock(sfd->ns, sfd->id);
 	BUG_ON(!shp);
 	shp->shm_atim = get_seconds();
 	shp->shm_lprid = current->tgid;
@@ -162,15 +175,6 @@ static inline void shm_inc(struct ipc_namespace *ns, int id)
 	shm_unlock(shp);
 }
 
-#define shm_file_ns(file) (*((struct ipc_namespace **)&(file)->private_data))
-
-/* This is called by fork, once for every shm attach. */
-static void shm_open(struct vm_area_struct *shmd)
-{
-	shm_inc(shm_file_ns(shmd->vm_file),
-			shmd->vm_file->f_path.dentry->d_inode->i_ino);
-}
-
 /*
  * shm_destroy - free the struct shmid_kernel
  *
@@ -195,23 +199,21 @@ static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
 }
 
 /*
- * remove the attach descriptor shmd.
+ * remove the attach descriptor vma.
  * free memory for segment if it is marked destroyed.
  * The descriptor has already been removed from the current->mm->mmap list
  * and will later be kfree()d.
  */
-static void shm_close (struct vm_area_struct *shmd)
+static void shm_close(struct vm_area_struct *vma)
 {
-	struct file * file = shmd->vm_file;
-	int id = file->f_path.dentry->d_inode->i_ino;
+	struct file * file = vma->vm_file;
+	struct shm_file_data *sfd = shm_file_data(file);
 	struct shmid_kernel *shp;
-	struct ipc_namespace *ns;
-
-	ns = shm_file_ns(file);
+	struct ipc_namespace *ns = sfd->ns;
 
 	mutex_lock(&shm_ids(ns).mutex);
 	/* remove from the list of attaches of the shm segment */
-	shp = shm_lock(ns, id);
+	shp = shm_lock(ns, sfd->id);
 	BUG_ON(!shp);
 	shp->shm_lprid = current->tgid;
 	shp->shm_dtim = get_seconds();
@@ -224,46 +226,91 @@ static void shm_close (struct vm_area_struct *shmd)
 	mutex_unlock(&shm_ids(ns).mutex);
 }
 
+struct page *shm_nopage(struct vm_area_struct *vma, unsigned long address,
+			int *type)
+{
+	struct file *file = vma->vm_file;
+	struct shm_file_data *sfd = shm_file_data(file);
+
+	return sfd->vm_ops->nopage(vma, address, type);
+}
+
+#ifdef CONFIG_NUMA
+int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
+{
+	struct file *file = vma->vm_file;
+	struct shm_file_data *sfd = shm_file_data(file);
+	int err = 0;
+	if (sfd->vm_ops->set_policy)
+		err = sfd->vm_ops->set_policy(vma, new);
+	return err;
+}
+
+struct mempolicy *shm_get_policy(struct vm_area_struct *vma, unsigned long addr)
+{
+	struct file *file = vma->vm_file;
+	struct shm_file_data *sfd = shm_file_data(file);
+	struct mempolicy *pol = NULL;
+
+	if (sfd->vm_ops->get_policy)
+		pol = sfd->vm_ops->get_policy(vma, addr);
+	else
+		pol = vma->vm_policy;
+	return pol;
+}
+#endif
+
 static int shm_mmap(struct file * file, struct vm_area_struct * vma)
 {
+	struct shm_file_data *sfd = shm_file_data(file);
 	int ret;
 
-	ret = shmem_mmap(file, vma);
-	if (ret == 0) {
-		vma->vm_ops = &shm_vm_ops;
-		if (!(vma->vm_flags & VM_WRITE))
-			vma->vm_flags &= ~VM_MAYWRITE;
-		shm_inc(shm_file_ns(file), file->f_path.dentry->d_inode->i_ino);
-	}
+	ret = sfd->file->f_op->mmap(sfd->file, vma);
+	if (ret != 0)
+		return ret;
+	sfd->vm_ops = vma->vm_ops;
+	vma->vm_ops = &shm_vm_ops;
+	shm_open(vma);
 
 	return ret;
 }
 
 static int shm_release(struct inode *ino, struct file *file)
 {
-	struct ipc_namespace *ns;
+	struct shm_file_data *sfd = shm_file_data(file);
 
-	ns = shm_file_ns(file);
-	put_ipc_ns(ns);
-	shm_file_ns(file) = NULL;
+	put_ipc_ns(sfd->ns);
+	shm_file_data(file) = NULL;
+	kfree(sfd);
 	return 0;
 }
 
+#ifndef CONFIG_MMU
+static unsigned long shm_get_unmapped_area(struct file *file,
+	unsigned long addr, unsigned long len, unsigned long pgoff,
+	unsigned long flags)
+{
+	struct shm_file_data *sfd = shm_file_data(file);
+	return sfd->file->f_op->get_unmapped_area(sfd->file, addr, len, pgoff,
+							flags);
+}
+#else
+#define shm_get_unmapped_area NULL
+#endif
+
 static const struct file_operations shm_file_operations = {
 	.mmap		= shm_mmap,
 	.release	= shm_release,
-#ifndef CONFIG_MMU
-	.get_unmapped_area = shmem_get_unmapped_area,
-#endif
+	.get_unmapped_area	= shm_get_unmapped_area,
 };
 
 static struct vm_operations_struct shm_vm_ops = {
 	.open	= shm_open,	/* callback for a new vm-area open */
 	.close	= shm_close,	/* callback for when the vm-area is released */
-	.nopage	= shmem_nopage,
-#if defined(CONFIG_NUMA) && defined(CONFIG_SHMEM)
-	.set_policy = shmem_set_policy,
-	.get_policy = shmem_get_policy,
+	.nopage	= shm_nopage,
+#if defined(CONFIG_NUMA)
+	.set_policy = shm_set_policy,
+	.get_policy = shm_get_policy,
 #endif
 };
 
@@ -330,13 +377,6 @@ static int newseg (struct ipc_namespace *ns, key_t key, int shmflg, size_t size)
 	shp->shm_nattch = 0;
 	shp->id = shm_buildid(ns, id, shp->shm_perm.seq);
 	shp->shm_file = file;
-	file->f_path.dentry->d_inode->i_ino = shp->id;
-
-	shm_file_ns(file) = get_ipc_ns(ns);
-
-	/* Hugetlb ops would have already been assigned. */
-	if (!(shmflg & SHM_HUGETLB))
-		file->f_op = &shm_file_operations;
 
 	ns->shm_tot += numpages;
 	shm_unlock(shp);
@@ -607,10 +647,7 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
 		tbuf.shm_ctime	= shp->shm_ctim;
 		tbuf.shm_cpid	= shp->shm_cprid;
 		tbuf.shm_lpid	= shp->shm_lprid;
-		if (!is_file_hugepages(shp->shm_file))
-			tbuf.shm_nattch	= shp->shm_nattch;
-		else
-			tbuf.shm_nattch = file_count(shp->shm_file) - 1;
+		tbuf.shm_nattch	= shp->shm_nattch;
 		shm_unlock(shp);
 		if(copy_shmid_to_user (buf, &tbuf, version))
 			err = -EFAULT;
@@ -779,13 +816,16 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 	unsigned long flags;
 	unsigned long prot;
 	int acc_mode;
-	void *user_addr;
+	unsigned long user_addr;
 	struct ipc_namespace *ns;
+	struct shm_file_data *sfd;
+	struct path path;
+	mode_t f_mode;
 
-	if (shmid < 0) {
-		err = -EINVAL;
+	err = -EINVAL;
+	if (shmid < 0)
 		goto out;
-	} else if ((addr = (ulong)shmaddr)) {
+	else if ((addr = (ulong)shmaddr)) {
 		if (addr & (SHMLBA-1)) {
 			if (shmflg & SHM_RND)
 				addr &= ~(SHMLBA-1);	   /* round down */
@@ -793,12 +833,12 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 #ifndef __ARCH_FORCE_SHMLBA
 				if (addr & ~PAGE_MASK)
 #endif
-					return -EINVAL;
+					goto out;
 		}
 		flags = MAP_SHARED | MAP_FIXED;
 	} else {
 		if ((shmflg & SHM_REMAP))
-			return -EINVAL;
+			goto out;
 
 		flags = MAP_SHARED;
 	}
@@ -806,9 +846,11 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 	if (shmflg & SHM_RDONLY) {
 		prot = PROT_READ;
 		acc_mode = S_IRUGO;
+		f_mode = FMODE_READ;
 	} else {
 		prot = PROT_READ | PROT_WRITE;
 		acc_mode = S_IRUGO | S_IWUGO;
+		f_mode = FMODE_READ | FMODE_WRITE;
 	}
 	if (shmflg & SHM_EXEC) {
 		prot |= PROT_EXEC;
@@ -821,35 +863,50 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 	 */
 	ns = current->nsproxy->ipc_ns;
 	shp = shm_lock(ns, shmid);
-	if(shp == NULL) {
-		err = -EINVAL;
+	if(shp == NULL)
 		goto out;
-	}
+
 	err = shm_checkid(ns, shp,shmid);
-	if (err) {
-		shm_unlock(shp);
-		goto out;
-	}
-	if (ipcperms(&shp->shm_perm, acc_mode)) {
-		shm_unlock(shp);
-		err = -EACCES;
-		goto out;
-	}
+	if (err)
+		goto out_unlock;
+
+	err = -EACCES;
+	if (ipcperms(&shp->shm_perm, acc_mode))
+		goto out_unlock;
 
 	err = security_shm_shmat(shp, shmaddr, shmflg);
-	if (err) {
-		shm_unlock(shp);
-		return err;
-	}
-		
-	file = shp->shm_file;
-	size = i_size_read(file->f_path.dentry->d_inode);
+	if (err)
+		goto out_unlock;
+
+	path.dentry = dget(shp->shm_file->f_path.dentry);
+	path.mnt    = mntget(shp->shm_file->f_path.mnt);
 	shp->shm_nattch++;
+	size = i_size_read(path.dentry->d_inode);
 	shm_unlock(shp);
 
+	err = -ENOMEM;
+	sfd = kzalloc(sizeof(*sfd), GFP_KERNEL);
+	if (!sfd)
+		goto out_put_path;
+
+	err = -ENOMEM;
+	file = get_empty_filp();
+	if (!file)
+		goto out_free;
+
+	file->f_op = &shm_file_operations;
+	file->private_data = sfd;
+	file->f_path = path;
+	file->f_mapping = shp->shm_file->f_mapping;
+	file->f_mode = f_mode;
+	sfd->id = shp->id;
+	sfd->ns = get_ipc_ns(ns);
+	sfd->file = shp->shm_file;
+	sfd->vm_ops = NULL;
+
 	down_write(&current->mm->mmap_sem);
 	if (addr && !(shmflg & SHM_REMAP)) {
-		user_addr = ERR_PTR(-EINVAL);
+		err = -EINVAL;
 		if (find_vma_intersection(current->mm, addr, addr + size))
 			goto invalid;
 		/*
@@ -861,11 +918,17 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 			goto invalid;
 	}
 		
-	user_addr = (void*) do_mmap (file, addr, size, prot, flags, 0);
-
+	user_addr = do_mmap (file, addr, size, prot, flags, 0);
+	*raddr = user_addr;
+	err = 0;
+	if (IS_ERR_VALUE(user_addr))
+		err = (long)user_addr;
 invalid:
 	up_write(&current->mm->mmap_sem);
 
+	fput(file);
+
+out_nattch:
 	mutex_lock(&shm_ids(ns).mutex);
 	shp = shm_lock(ns, shmid);
 	BUG_ON(!shp);
@@ -877,12 +940,19 @@ invalid:
 		shm_unlock(shp);
 	mutex_unlock(&shm_ids(ns).mutex);
 
-	*raddr = (unsigned long) user_addr;
-	err = 0;
-	if (IS_ERR(user_addr))
-		err = PTR_ERR(user_addr);
 out:
 	return err;
+
+out_unlock:
+	shm_unlock(shp);
+	goto out;
+
+out_free:
+	kfree(sfd);
+out_put_path:
+	dput(path.dentry);
+	mntput(path.mnt);
+	goto out_nattch;
 }
 
 asmlinkage long sys_shmat(int shmid, char __user *shmaddr, int shmflg)
@@ -944,7 +1014,7 @@ asmlinkage long sys_shmdt(char __user *shmaddr)
 		 * a fragment created by mprotect() and/or munmap(), or it
 		 * otherwise it starts at this address with no hassles.
 		 */
-		if ((vma->vm_ops == &shm_vm_ops || is_vm_hugetlb_page(vma)) &&
+		if ((vma->vm_ops == &shm_vm_ops) &&
 			(vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) {
 
 
@@ -973,7 +1043,7 @@ asmlinkage long sys_shmdt(char __user *shmaddr)
 		next = vma->vm_next;
 
 		/* finding a matching vma now does not alter retval */
-		if ((vma->vm_ops == &shm_vm_ops || is_vm_hugetlb_page(vma)) &&
+		if ((vma->vm_ops == &shm_vm_ops) &&
 			(vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff)
 
 			do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
@@ -1004,7 +1074,7 @@ static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
 			  shp->shm_segsz,
 			  shp->shm_cprid,
 			  shp->shm_lprid,
-			  is_file_hugepages(shp->shm_file) ? (file_count(shp->shm_file) - 1) : shp->shm_nattch,
+			  shp->shm_nattch,
 			  shp->shm_perm.uid,
 			  shp->shm_perm.gid,
 			  shp->shm_perm.cuid,