1 files changed, 155 insertions, 85 deletions

diff --git a/ipc/shm.c b/ipc/shm.c
index 5bb617f6306e..eb57e2254304 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,