ipc: unify the syscalls code
[safe/jmp/linux-2.6] / ipc / shm.c
index bfbd317..d20cc25 100644 (file)
--- a/ipc/shm.c
+++ b/ipc/shm.c
 #include <linux/seq_file.h>
 #include <linux/mutex.h>
 #include <linux/nsproxy.h>
+#include <linux/mount.h>
 
 #include <asm/uaccess.h>
 
 #include "util.h"
 
-static struct file_operations shm_file_operations;
+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;
 
 static struct ipc_ids init_shm_ids;
@@ -58,23 +68,22 @@ static struct ipc_ids init_shm_ids;
 #define shm_buildid(ns, id, seq)       \
        ipc_buildid(&shm_ids(ns), id, seq)
 
-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 int newseg(struct ipc_namespace *, struct ipc_params *);
+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);
 #endif
 
-static void __ipc_init __shm_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
+static void __shm_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
 {
        ns->ids[IPC_SHM_IDS] = ids;
        ns->shm_ctlmax = SHMMAX;
        ns->shm_ctlall = SHMALL;
        ns->shm_ctlmni = SHMMNI;
        ns->shm_tot = 0;
-       ipc_init_ids(ids, 1);
+       ipc_init_ids(ids);
 }
 
 static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
@@ -88,7 +97,6 @@ static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
                shm_destroy(ns, shp);
 }
 
-#ifdef CONFIG_IPC_NS
 int shm_init_ns(struct ipc_namespace *ns)
 {
        struct ipc_ids *ids;
@@ -103,23 +111,27 @@ int shm_init_ns(struct ipc_namespace *ns)
 
 void shm_exit_ns(struct ipc_namespace *ns)
 {
-       int i;
        struct shmid_kernel *shp;
+       int next_id;
+       int total, in_use;
 
        mutex_lock(&shm_ids(ns).mutex);
-       for (i = 0; i <= shm_ids(ns).max_id; i++) {
-               shp = shm_lock(ns, i);
+
+       in_use = shm_ids(ns).in_use;
+
+       for (total = 0, next_id = 0; total < in_use; next_id++) {
+               shp = idr_find(&shm_ids(ns).ipcs_idr, next_id);
                if (shp == NULL)
                        continue;
-
+               ipc_lock_by_ptr(&shp->shm_perm);
                do_shm_rmid(ns, shp);
+               total++;
        }
        mutex_unlock(&shm_ids(ns).mutex);
 
        kfree(ns->ids[IPC_SHM_IDS]);
        ns->ids[IPC_SHM_IDS] = NULL;
 }
-#endif
 
 void __init shm_init (void)
 {
@@ -137,9 +149,9 @@ static inline int shm_checkid(struct ipc_namespace *ns,
        return 0;
 }
 
-static inline struct shmid_kernel *shm_rmid(struct ipc_namespace *ns, int id)
+static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
 {
-       return (struct shmid_kernel *)ipc_rmid(&shm_ids(ns), id);
+       ipc_rmid(&shm_ids(ns), &s->shm_perm);
 }
 
 static inline int shm_addid(struct ipc_namespace *ns, struct shmid_kernel *shp)
@@ -149,27 +161,21 @@ 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;
+       shp->shm_lprid = task_tgid_vnr(current);
        shp->shm_nattch++;
        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_dentry->d_inode->i_ino);
-}
-
 /*
  * shm_destroy - free the struct shmid_kernel
  *
@@ -181,12 +187,12 @@ static void shm_open(struct vm_area_struct *shmd)
 static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
 {
        ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
-       shm_rmid(ns, shp->id);
+       shm_rmid(ns, shp);
        shm_unlock(shp);
        if (!is_file_hugepages(shp->shm_file))
                shmem_lock(shp->shm_file, 0, shp->mlock_user);
        else
-               user_shm_unlock(shp->shm_file->f_dentry->d_inode->i_size,
+               user_shm_unlock(shp->shm_file->f_path.dentry->d_inode->i_size,
                                                shp->mlock_user);
        fput (shp->shm_file);
        security_shm_free(shp);
@@ -194,25 +200,23 @@ 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_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_lprid = task_tgid_vnr(current);
        shp->shm_dtim = get_seconds();
        shp->shm_nattch--;
        if(shp->shm_nattch == 0 &&
@@ -223,51 +227,124 @@ static void shm_close (struct vm_area_struct *shmd)
        mutex_unlock(&shm_ids(ns).mutex);
 }
 
+static int shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+       struct file *file = vma->vm_file;
+       struct shm_file_data *sfd = shm_file_data(file);
+
+       return sfd->vm_ops->fault(vma, vmf);
+}
+
+#ifdef CONFIG_NUMA
+static 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;
+}
+
+static 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 if (vma->vm_policy)
+               pol = vma->vm_policy;
+       else
+               pol = current->mempolicy;
+       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_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;
+#ifdef CONFIG_MMU
+       BUG_ON(!sfd->vm_ops->fault);
+#endif
+       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;
 }
 
-static struct file_operations shm_file_operations = {
+static int shm_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+       int (*fsync) (struct file *, struct dentry *, int datasync);
+       struct shm_file_data *sfd = shm_file_data(file);
+       int ret = -EINVAL;
+
+       fsync = sfd->file->f_op->fsync;
+       if (fsync)
+               ret = fsync(sfd->file, sfd->file->f_path.dentry, datasync);
+       return ret;
+}
+
+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 get_unmapped_area(sfd->file, addr, len, pgoff, flags);
+}
+
+int is_file_shm_hugepages(struct file *file)
+{
+       int ret = 0;
+
+       if (file->f_op == &shm_file_operations) {
+               struct shm_file_data *sfd;
+               sfd = shm_file_data(file);
+               ret = is_file_hugepages(sfd->file);
+       }
+       return ret;
+}
+
+static const struct file_operations shm_file_operations = {
        .mmap           = shm_mmap,
+       .fsync          = shm_fsync,
        .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,
+       .fault  = shm_fault,
+#if defined(CONFIG_NUMA)
+       .set_policy = shm_set_policy,
+       .get_policy = shm_get_policy,
 #endif
 };
 
-static int newseg (struct ipc_namespace *ns, key_t key, int shmflg, size_t size)
+static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
 {
+       key_t key = params->key;
+       int shmflg = params->flg;
+       size_t size = params->u.size;
        int error;
        struct shmid_kernel *shp;
        int numpages = (size + PAGE_SIZE -1) >> PAGE_SHIFT;
@@ -278,7 +355,7 @@ static int newseg (struct ipc_namespace *ns, key_t key, int shmflg, size_t size)
        if (size < SHMMIN || size > ns->shm_ctlmax)
                return -EINVAL;
 
-       if (ns->shm_tot + numpages >= ns->shm_ctlall)
+       if (ns->shm_tot + numpages > ns->shm_ctlall)
                return -ENOSPC;
 
        shp = ipc_rcu_alloc(sizeof(*shp));
@@ -296,9 +373,10 @@ static int newseg (struct ipc_namespace *ns, key_t key, int shmflg, size_t size)
                return error;
        }
 
+       sprintf (name, "SYSV%08x", key);
        if (shmflg & SHM_HUGETLB) {
-               /* hugetlb_zero_setup takes care of mlock user accounting */
-               file = hugetlb_zero_setup(size);
+               /* hugetlb_file_setup takes care of mlock user accounting */
+               file = hugetlb_file_setup(name, size);
                shp->mlock_user = current->user;
        } else {
                int acctflag = VM_ACCOUNT;
@@ -309,7 +387,6 @@ static int newseg (struct ipc_namespace *ns, key_t key, int shmflg, size_t size)
                if  ((shmflg & SHM_NORESERVE) &&
                                sysctl_overcommit_memory != OVERCOMMIT_NEVER)
                        acctflag = 0;
-               sprintf (name, "SYSV%08x", key);
                file = shmem_file_setup(name, size, acctflag);
        }
        error = PTR_ERR(file);
@@ -321,25 +398,24 @@ static int newseg (struct ipc_namespace *ns, key_t key, int shmflg, size_t size)
        if(id == -1) 
                goto no_id;
 
-       shp->shm_cprid = current->tgid;
+       shp->shm_cprid = task_tgid_vnr(current);
        shp->shm_lprid = 0;
        shp->shm_atim = shp->shm_dtim = 0;
        shp->shm_ctim = get_seconds();
        shp->shm_segsz = size;
        shp->shm_nattch = 0;
-       shp->id = shm_buildid(ns, id, shp->shm_perm.seq);
+       shp->shm_perm.id = shm_buildid(ns, id, shp->shm_perm.seq);
        shp->shm_file = file;
-       file->f_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;
+       /*
+        * shmid gets reported as "inode#" in /proc/pid/maps.
+        * proc-ps tools use this. Changing this will break them.
+        */
+       file->f_dentry->d_inode->i_ino = shp->shm_perm.id;
 
        ns->shm_tot += numpages;
+       error = shp->shm_perm.id;
        shm_unlock(shp);
-       return shp->id;
+       return error;
 
 no_id:
        fput(file);
@@ -349,42 +425,36 @@ no_file:
        return error;
 }
 
+static inline int shm_security(void *shp, int shmflg)
+{
+       return security_shm_associate((struct shmid_kernel *) shp, shmflg);
+}
+
+static inline int shm_more_checks(void *shp, struct ipc_params *params)
+{
+       if (((struct shmid_kernel *)shp)->shm_segsz < params->u.size)
+               return -EINVAL;
+
+       return 0;
+}
+
 asmlinkage long sys_shmget (key_t key, size_t size, int shmflg)
 {
-       struct shmid_kernel *shp;
-       int err, id = 0;
        struct ipc_namespace *ns;
+       struct ipc_ops shm_ops;
+       struct ipc_params shm_params;
 
        ns = current->nsproxy->ipc_ns;
 
-       mutex_lock(&shm_ids(ns).mutex);
-       if (key == IPC_PRIVATE) {
-               err = newseg(ns, key, shmflg, size);
-       } else if ((id = ipc_findkey(&shm_ids(ns), key)) == -1) {
-               if (!(shmflg & IPC_CREAT))
-                       err = -ENOENT;
-               else
-                       err = newseg(ns, key, shmflg, size);
-       } else if ((shmflg & IPC_CREAT) && (shmflg & IPC_EXCL)) {
-               err = -EEXIST;
-       } else {
-               shp = shm_lock(ns, id);
-               BUG_ON(shp==NULL);
-               if (shp->shm_segsz < size)
-                       err = -EINVAL;
-               else if (ipcperms(&shp->shm_perm, shmflg))
-                       err = -EACCES;
-               else {
-                       int shmid = shm_buildid(ns, id, shp->shm_perm.seq);
-                       err = security_shm_associate(shp, shmflg);
-                       if (!err)
-                               err = shmid;
-               }
-               shm_unlock(shp);
-       }
-       mutex_unlock(&shm_ids(ns).mutex);
+       shm_ops.getnew = newseg;
+       shm_ops.associate = shm_security;
+       shm_ops.more_checks = shm_more_checks;
 
-       return err;
+       shm_params.key = key;
+       shm_params.flg = shmflg;
+       shm_params.u.size = size;
+
+       return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params);
 }
 
 static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version)
@@ -481,20 +551,23 @@ static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminf
 static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
                unsigned long *swp)
 {
-       int i;
+       int next_id;
+       int total, in_use;
 
        *rss = 0;
        *swp = 0;
 
-       for (i = 0; i <= shm_ids(ns).max_id; i++) {
+       in_use = shm_ids(ns).in_use;
+
+       for (total = 0, next_id = 0; total < in_use; next_id++) {
                struct shmid_kernel *shp;
                struct inode *inode;
 
-               shp = shm_get(ns, i);
-               if(!shp)
+               shp = shm_get(ns, next_id);
+               if (shp == NULL)
                        continue;
 
-               inode = shp->shm_file->f_dentry->d_inode;
+               inode = shp->shm_file->f_path.dentry->d_inode;
 
                if (is_file_hugepages(shp->shm_file)) {
                        struct address_space *mapping = inode->i_mapping;
@@ -506,6 +579,8 @@ static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
                        *swp += info->swapped;
                        spin_unlock(&info->lock);
                }
+
+               total++;
        }
 }
 
@@ -542,7 +617,7 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
                if(copy_shminfo_to_user (buf, &shminfo, version))
                        return -EFAULT;
                /* reading a integer is always atomic */
-               err= shm_ids(ns).max_id;
+               err = ipc_get_maxid(&shm_ids(ns));
                if(err<0)
                        err = 0;
                goto out;
@@ -562,7 +637,7 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
                shm_info.shm_tot = ns->shm_tot;
                shm_info.swap_attempts = 0;
                shm_info.swap_successes = 0;
-               err = shm_ids(ns).max_id;
+               err = ipc_get_maxid(&shm_ids(ns));
                mutex_unlock(&shm_ids(ns).mutex);
                if(copy_to_user (buf, &shm_info, sizeof(shm_info))) {
                        err = -EFAULT;
@@ -582,11 +657,8 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
                if(shp==NULL) {
                        err = -EINVAL;
                        goto out;
-               } else if(cmd==SHM_STAT) {
-                       err = -EINVAL;
-                       if (shmid > shm_ids(ns).max_id)
-                               goto out_unlock;
-                       result = shm_buildid(ns, shmid, shp->shm_perm.seq);
+               } else if (cmd == SHM_STAT) {
+                       result = shp->shm_perm.id;
                } else {
                        err = shm_checkid(ns, shp,shmid);
                        if(err)
@@ -606,10 +678,7 @@ 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;
@@ -651,7 +720,7 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
                        struct user_struct * user = current->user;
                        if (!is_file_hugepages(shp->shm_file)) {
                                err = shmem_lock(shp->shm_file, 1, user);
-                               if (!err{
+                               if (!err && !(shp->shm_perm.mode & SHM_LOCKED)){
                                        shp->shm_perm.mode |= SHM_LOCKED;
                                        shp->mlock_user = user;
                                }
@@ -778,13 +847,16 @@ 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 */
@@ -792,12 +864,12 @@ 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;
        }
@@ -805,9 +877,11 @@ 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;
@@ -820,35 +894,48 @@ 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_dentry->d_inode);
+       if (err)
+               goto out_unlock;
+
+       path.dentry = dget(shp->shm_file->f_path.dentry);
+       path.mnt    = 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_dentry;
+
+       err = -ENOMEM;
+
+       file = alloc_file(path.mnt, path.dentry, f_mode, &shm_file_operations);
+       if (!file)
+               goto out_free;
+
+       file->private_data = sfd;
+       file->f_mapping = shp->shm_file->f_mapping;
+       sfd->id = shp->shm_perm.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;
                /*
@@ -860,11 +947,17 @@ 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);
@@ -876,12 +969,18 @@ 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_dentry:
+       dput(path.dentry);
+       goto out_nattch;
 }
 
 asmlinkage long sys_shmat(int shmid, char __user *shmaddr, int shmflg)
@@ -943,11 +1042,11 @@ 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) {
 
 
-                       size = vma->vm_file->f_dentry->d_inode->i_size;
+                       size = vma->vm_file->f_path.dentry->d_inode->i_size;
                        do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
                        /*
                         * We discovered the size of the shm segment, so
@@ -972,7 +1071,7 @@ 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);
@@ -998,12 +1097,12 @@ static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
                format = BIG_STRING;
        return seq_printf(s, format,
                          shp->shm_perm.key,
-                         shp->id,
+                         shp->shm_perm.id,
                          shp->shm_perm.mode,
                          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,