| Message ID | 863b9c951827a05978eddd241b62db4e48294a80.1546399191.git.yi.z.zhang@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | support MAP_SYNC for memory-backend-file | expand |
On Wed, Jan 02, 2019 at 01:26:06PM +0800, Zhang Yi wrote: > As more flag parameters besides the existing 'shared' are going to be > added to qemu_ram_mmap(), let's switch 'shared' to a 'flags' parameter > in advance, so as to ease the further additions. > > Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com> > Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com> > --- > exec.c | 7 ++++--- > include/exec/memory.h | 22 ++++++++++++++++------ > include/qemu/mmap-alloc.h | 19 ++++++++++++++++++- > util/mmap-alloc.c | 8 +++++--- > util/oslib-posix.c | 9 ++++++++- > 5 files changed, 51 insertions(+), 14 deletions(-) > > diff --git a/exec.c b/exec.c > index bb6170d..e92a7da 100644 > --- a/exec.c > +++ b/exec.c > @@ -1810,6 +1810,7 @@ static void *file_ram_alloc(RAMBlock *block, > ram_addr_t memory, > int fd, > bool truncate, > + uint32_t flags, > Error **errp) I suggest documenting on the commit message why you are changing file_ram_alloc() too. The commit message mentions only qemu_ram_mmap(). > { > void *area; > @@ -1859,8 +1860,7 @@ static void *file_ram_alloc(RAMBlock *block, > perror("ftruncate"); > } > > - area = qemu_ram_mmap(fd, memory, block->mr->align, > - block->flags & RAM_SHARED); > + area = qemu_ram_mmap(fd, memory, block->mr->align, flags); > if (area == MAP_FAILED) { > error_setg_errno(errp, errno, > "unable to map backing store for guest RAM"); > @@ -2279,7 +2279,8 @@ RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr, > new_block->used_length = size; > new_block->max_length = size; > new_block->flags = ram_flags; > - new_block->host = file_ram_alloc(new_block, size, fd, !file_size, errp); > + new_block->host = file_ram_alloc(new_block, size, fd, !file_size, > + ram_flags, errp); > if (!new_block->host) { > g_free(new_block); > return NULL; > diff --git a/include/exec/memory.h b/include/exec/memory.h > index 667466b..6e30c23 100644 > --- a/include/exec/memory.h > +++ b/include/exec/memory.h > @@ -103,28 +103,38 @@ struct IOMMUNotifier { > }; > typedef struct IOMMUNotifier IOMMUNotifier; > > +#ifdef __CHECKER__ > +#define QEMU_BITWISE __attribute__((bitwise)) > +#define QEMU_FORCE __attribute__((force)) > +#else > +#define QEMU_BITWISE > +#define QEMU_FORCE > +#endif > + I assume this is a sparse feature? Why is it part of this patch? I suggest doing this in a separate patch series and in a common header file, so other developers have a better chance to review it and decide how to use this sparse feature in QEMU. > +typedef unsigned QEMU_BITWISE QemuMmapFlags; > + > /* RAM is pre-allocated and passed into qemu_ram_alloc_from_ptr */ > -#define RAM_PREALLOC (1 << 0) > +#define RAM_PREALLOC ((QEMU_FORCE QemuMmapFlags) (1 << 0)) > > /* RAM is mmap-ed with MAP_SHARED */ > -#define RAM_SHARED (1 << 1) > +#define RAM_SHARED ((QEMU_FORCE QemuMmapFlags) (1 << 1)) > > /* Only a portion of RAM (used_length) is actually used, and migrated. > * This used_length size can change across reboots. > */ > -#define RAM_RESIZEABLE (1 << 2) > +#define RAM_RESIZEABLE ((QEMU_FORCE QemuMmapFlags) (1 << 2)) > > /* UFFDIO_ZEROPAGE is available on this RAMBlock to atomically > * zero the page and wake waiting processes. > * (Set during postcopy) > */ > -#define RAM_UF_ZEROPAGE (1 << 3) > +#define RAM_UF_ZEROPAGE ((QEMU_FORCE QemuMmapFlags) (1 << 3)) > > /* RAM can be migrated */ > -#define RAM_MIGRATABLE (1 << 4) > +#define RAM_MIGRATABLE ((QEMU_FORCE QemuMmapFlags) (1 << 4)) > > /* RAM is a persistent kind memory */ > -#define RAM_PMEM (1 << 5) > +#define RAM_PMEM ((QEMU_FORCE QemuMmapFlags) (1 << 5)) > > static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn, > IOMMUNotifierFlag flags, > diff --git a/include/qemu/mmap-alloc.h b/include/qemu/mmap-alloc.h > index 50385e3..6fe6ed4 100644 > --- a/include/qemu/mmap-alloc.h > +++ b/include/qemu/mmap-alloc.h > @@ -7,7 +7,24 @@ size_t qemu_fd_getpagesize(int fd); > > size_t qemu_mempath_getpagesize(const char *mem_path); > > -void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared); > +/** > + * qemu_ram_mmap: mmap the specified file or device. > + * > + * Parameters: > + * @fd: the file or the device to mmap > + * @size: the number of bytes to be mmaped > + * @align: if not zero, specify the alignment of the starting mapping address; > + * otherwise, the alignment in use will be determined by QEMU. > + * @flags: specifies additional properties of the mapping, which can be one or > + * bit-or of following values > + * - RAM_SHARED: mmap with MAP_SHARED flag > + * Other bits are ignored. > + * > + * Return: > + * On success, return a pointer to the mapped area. > + * On failure, return MAP_FAILED. > + */ > +void *qemu_ram_mmap(int fd, size_t size, size_t align, uint32_t flags); > > void qemu_ram_munmap(void *ptr, size_t size); > > diff --git a/util/mmap-alloc.c b/util/mmap-alloc.c > index fd329ec..8f0a740 100644 > --- a/util/mmap-alloc.c > +++ b/util/mmap-alloc.c > @@ -13,6 +13,7 @@ > #include "qemu/osdep.h" > #include "qemu/mmap-alloc.h" > #include "qemu/host-utils.h" > +#include "exec/memory.h" > > #define HUGETLBFS_MAGIC 0x958458f6 > > @@ -75,7 +76,7 @@ size_t qemu_mempath_getpagesize(const char *mem_path) > return getpagesize(); > } > > -void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) > +void *qemu_ram_mmap(int fd, size_t size, size_t align, uint32_t flags) > { > /* > * Note: this always allocates at least one extra page of virtual address > @@ -92,11 +93,12 @@ void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) > * anonymous memory is OK. > */ > int anonfd = fd == -1 || qemu_fd_getpagesize(fd) == getpagesize() ? -1 : fd; > - int flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; > - void *ptr = mmap(0, total, PROT_NONE, flags | MAP_PRIVATE, anonfd, 0); > + int mmap_flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; > + void *ptr = mmap(0, total, PROT_NONE, mmap_flags | MAP_PRIVATE, anonfd, 0); > #else > void *ptr = mmap(0, total, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); > #endif > + bool shared = flags & RAM_SHARED; > size_t offset; > void *ptr1; > > diff --git a/util/oslib-posix.c b/util/oslib-posix.c > index fbd0dc8..75a0171 100644 > --- a/util/oslib-posix.c > +++ b/util/oslib-posix.c > @@ -54,6 +54,7 @@ > #endif > > #include "qemu/mmap-alloc.h" > +#include "exec/memory.h" > > #ifdef CONFIG_DEBUG_STACK_USAGE > #include "qemu/error-report.h" > @@ -203,7 +204,13 @@ void *qemu_memalign(size_t alignment, size_t size) > void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment, bool shared) > { > size_t align = QEMU_VMALLOC_ALIGN; > - void *ptr = qemu_ram_mmap(-1, size, align, shared); > + uint32_t flags = 0; > + void *ptr; > + > + if (shared) { > + flags = RAM_SHARED; > + } > + ptr = qemu_ram_mmap(-1, size, align, flags); > > if (ptr == MAP_FAILED) { > return NULL; > -- > 2.7.4 > >
On Mon, Jan 14, 2019 at 04:50:36PM -0200, Eduardo Habkost wrote: > On Wed, Jan 02, 2019 at 01:26:06PM +0800, Zhang Yi wrote: > > As more flag parameters besides the existing 'shared' are going to be > > added to qemu_ram_mmap(), let's switch 'shared' to a 'flags' parameter > > in advance, so as to ease the further additions. > > > > Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com> > > Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com> > > --- > > exec.c | 7 ++++--- > > include/exec/memory.h | 22 ++++++++++++++++------ > > include/qemu/mmap-alloc.h | 19 ++++++++++++++++++- > > util/mmap-alloc.c | 8 +++++--- > > util/oslib-posix.c | 9 ++++++++- > > 5 files changed, 51 insertions(+), 14 deletions(-) > > > > diff --git a/exec.c b/exec.c > > index bb6170d..e92a7da 100644 > > --- a/exec.c > > +++ b/exec.c > > @@ -1810,6 +1810,7 @@ static void *file_ram_alloc(RAMBlock *block, > > ram_addr_t memory, > > int fd, > > bool truncate, > > + uint32_t flags, > > Error **errp) > > I suggest documenting on the commit message why you are changing > file_ram_alloc() too. The commit message mentions only > qemu_ram_mmap(). > > > { > > void *area; > > @@ -1859,8 +1860,7 @@ static void *file_ram_alloc(RAMBlock *block, > > perror("ftruncate"); > > } > > > > - area = qemu_ram_mmap(fd, memory, block->mr->align, > > - block->flags & RAM_SHARED); > > + area = qemu_ram_mmap(fd, memory, block->mr->align, flags); > > if (area == MAP_FAILED) { > > error_setg_errno(errp, errno, > > "unable to map backing store for guest RAM"); > > @@ -2279,7 +2279,8 @@ RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr, > > new_block->used_length = size; > > new_block->max_length = size; > > new_block->flags = ram_flags; > > - new_block->host = file_ram_alloc(new_block, size, fd, !file_size, errp); > > + new_block->host = file_ram_alloc(new_block, size, fd, !file_size, > > + ram_flags, errp); > > if (!new_block->host) { > > g_free(new_block); > > return NULL; > > diff --git a/include/exec/memory.h b/include/exec/memory.h > > index 667466b..6e30c23 100644 > > --- a/include/exec/memory.h > > +++ b/include/exec/memory.h > > @@ -103,28 +103,38 @@ struct IOMMUNotifier { > > }; > > typedef struct IOMMUNotifier IOMMUNotifier; > > > > +#ifdef __CHECKER__ > > +#define QEMU_BITWISE __attribute__((bitwise)) > > +#define QEMU_FORCE __attribute__((force)) > > +#else > > +#define QEMU_BITWISE > > +#define QEMU_FORCE > > +#endif > > + > > I assume this is a sparse feature? > > Why is it part of this patch? I suggest doing this in a separate > patch series and in a common header file, so other developers > have a better chance to review it and decide how to use this > sparse feature in QEMU. It's needed for this series but yes, this ifdefery belongs in a more central header. Maybe qemu/osdep.h And it needs documentation and be a separate patch. > > > +typedef unsigned QEMU_BITWISE QemuMmapFlags; > > + > > /* RAM is pre-allocated and passed into qemu_ram_alloc_from_ptr */ > > -#define RAM_PREALLOC (1 << 0) > > +#define RAM_PREALLOC ((QEMU_FORCE QemuMmapFlags) (1 << 0)) > > > > /* RAM is mmap-ed with MAP_SHARED */ > > -#define RAM_SHARED (1 << 1) > > +#define RAM_SHARED ((QEMU_FORCE QemuMmapFlags) (1 << 1)) > > > > /* Only a portion of RAM (used_length) is actually used, and migrated. > > * This used_length size can change across reboots. > > */ > > -#define RAM_RESIZEABLE (1 << 2) > > +#define RAM_RESIZEABLE ((QEMU_FORCE QemuMmapFlags) (1 << 2)) > > > > /* UFFDIO_ZEROPAGE is available on this RAMBlock to atomically > > * zero the page and wake waiting processes. > > * (Set during postcopy) > > */ > > -#define RAM_UF_ZEROPAGE (1 << 3) > > +#define RAM_UF_ZEROPAGE ((QEMU_FORCE QemuMmapFlags) (1 << 3)) > > > > /* RAM can be migrated */ > > -#define RAM_MIGRATABLE (1 << 4) > > +#define RAM_MIGRATABLE ((QEMU_FORCE QemuMmapFlags) (1 << 4)) > > > > /* RAM is a persistent kind memory */ > > -#define RAM_PMEM (1 << 5) > > +#define RAM_PMEM ((QEMU_FORCE QemuMmapFlags) (1 << 5)) > > > > static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn, > > IOMMUNotifierFlag flags, > > diff --git a/include/qemu/mmap-alloc.h b/include/qemu/mmap-alloc.h > > index 50385e3..6fe6ed4 100644 > > --- a/include/qemu/mmap-alloc.h > > +++ b/include/qemu/mmap-alloc.h > > @@ -7,7 +7,24 @@ size_t qemu_fd_getpagesize(int fd); > > > > size_t qemu_mempath_getpagesize(const char *mem_path); > > > > -void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared); > > +/** > > + * qemu_ram_mmap: mmap the specified file or device. > > + * > > + * Parameters: > > + * @fd: the file or the device to mmap > > + * @size: the number of bytes to be mmaped > > + * @align: if not zero, specify the alignment of the starting mapping address; > > + * otherwise, the alignment in use will be determined by QEMU. > > + * @flags: specifies additional properties of the mapping, which can be one or > > + * bit-or of following values > > + * - RAM_SHARED: mmap with MAP_SHARED flag > > + * Other bits are ignored. > > + * > > + * Return: > > + * On success, return a pointer to the mapped area. > > + * On failure, return MAP_FAILED. > > + */ > > +void *qemu_ram_mmap(int fd, size_t size, size_t align, uint32_t flags); > > > > void qemu_ram_munmap(void *ptr, size_t size); > > > > diff --git a/util/mmap-alloc.c b/util/mmap-alloc.c > > index fd329ec..8f0a740 100644 > > --- a/util/mmap-alloc.c > > +++ b/util/mmap-alloc.c > > @@ -13,6 +13,7 @@ > > #include "qemu/osdep.h" > > #include "qemu/mmap-alloc.h" > > #include "qemu/host-utils.h" > > +#include "exec/memory.h" > > > > #define HUGETLBFS_MAGIC 0x958458f6 > > > > @@ -75,7 +76,7 @@ size_t qemu_mempath_getpagesize(const char *mem_path) > > return getpagesize(); > > } > > > > -void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) > > +void *qemu_ram_mmap(int fd, size_t size, size_t align, uint32_t flags) > > { > > /* > > * Note: this always allocates at least one extra page of virtual address > > @@ -92,11 +93,12 @@ void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) > > * anonymous memory is OK. > > */ > > int anonfd = fd == -1 || qemu_fd_getpagesize(fd) == getpagesize() ? -1 : fd; > > - int flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; > > - void *ptr = mmap(0, total, PROT_NONE, flags | MAP_PRIVATE, anonfd, 0); > > + int mmap_flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; > > + void *ptr = mmap(0, total, PROT_NONE, mmap_flags | MAP_PRIVATE, anonfd, 0); > > #else > > void *ptr = mmap(0, total, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); > > #endif > > + bool shared = flags & RAM_SHARED; > > size_t offset; > > void *ptr1; > > > > diff --git a/util/oslib-posix.c b/util/oslib-posix.c > > index fbd0dc8..75a0171 100644 > > --- a/util/oslib-posix.c > > +++ b/util/oslib-posix.c > > @@ -54,6 +54,7 @@ > > #endif > > > > #include "qemu/mmap-alloc.h" > > +#include "exec/memory.h" > > > > #ifdef CONFIG_DEBUG_STACK_USAGE > > #include "qemu/error-report.h" > > @@ -203,7 +204,13 @@ void *qemu_memalign(size_t alignment, size_t size) > > void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment, bool shared) > > { > > size_t align = QEMU_VMALLOC_ALIGN; > > - void *ptr = qemu_ram_mmap(-1, size, align, shared); > > + uint32_t flags = 0; > > + void *ptr; > > + > > + if (shared) { > > + flags = RAM_SHARED; > > + } > > + ptr = qemu_ram_mmap(-1, size, align, flags); > > > > if (ptr == MAP_FAILED) { > > return NULL; > > -- > > 2.7.4 > > > > > > -- > Eduardo
On 2019-01-14 at 14:04:25 -0500, Michael S. Tsirkin wrote: > On Mon, Jan 14, 2019 at 04:50:36PM -0200, Eduardo Habkost wrote: > > On Wed, Jan 02, 2019 at 01:26:06PM +0800, Zhang Yi wrote: > > > As more flag parameters besides the existing 'shared' are going to be > > > added to qemu_ram_mmap(), let's switch 'shared' to a 'flags' parameter > > > in advance, so as to ease the further additions. > > > > > > Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com> > > > Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com> > > > --- > > > exec.c | 7 ++++--- > > > include/exec/memory.h | 22 ++++++++++++++++------ > > > include/qemu/mmap-alloc.h | 19 ++++++++++++++++++- > > > util/mmap-alloc.c | 8 +++++--- > > > util/oslib-posix.c | 9 ++++++++- > > > 5 files changed, 51 insertions(+), 14 deletions(-) > > > > > > diff --git a/exec.c b/exec.c > > > index bb6170d..e92a7da 100644 > > > --- a/exec.c > > > +++ b/exec.c > > > @@ -1810,6 +1810,7 @@ static void *file_ram_alloc(RAMBlock *block, > > > ram_addr_t memory, > > > int fd, > > > bool truncate, > > > + uint32_t flags, > > > Error **errp) > > > > I suggest documenting on the commit message why you are changing > > file_ram_alloc() too. The commit message mentions only > > qemu_ram_mmap(). > > > > > { > > > void *area; > > > @@ -1859,8 +1860,7 @@ static void *file_ram_alloc(RAMBlock *block, > > > perror("ftruncate"); > > > } > > > > > > - area = qemu_ram_mmap(fd, memory, block->mr->align, > > > - block->flags & RAM_SHARED); > > > + area = qemu_ram_mmap(fd, memory, block->mr->align, flags); > > > if (area == MAP_FAILED) { > > > error_setg_errno(errp, errno, > > > "unable to map backing store for guest RAM"); > > > @@ -2279,7 +2279,8 @@ RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr, > > > new_block->used_length = size; > > > new_block->max_length = size; > > > new_block->flags = ram_flags; > > > - new_block->host = file_ram_alloc(new_block, size, fd, !file_size, errp); > > > + new_block->host = file_ram_alloc(new_block, size, fd, !file_size, > > > + ram_flags, errp); > > > if (!new_block->host) { > > > g_free(new_block); > > > return NULL; > > > diff --git a/include/exec/memory.h b/include/exec/memory.h > > > index 667466b..6e30c23 100644 > > > --- a/include/exec/memory.h > > > +++ b/include/exec/memory.h > > > @@ -103,28 +103,38 @@ struct IOMMUNotifier { > > > }; > > > typedef struct IOMMUNotifier IOMMUNotifier; > > > > > > +#ifdef __CHECKER__ > > > +#define QEMU_BITWISE __attribute__((bitwise)) > > > +#define QEMU_FORCE __attribute__((force)) > > > +#else > > > +#define QEMU_BITWISE > > > +#define QEMU_FORCE > > > +#endif > > > + > > > > I assume this is a sparse feature? > > > > Why is it part of this patch? I suggest doing this in a separate > > patch series and in a common header file, so other developers > > have a better chance to review it and decide how to use this > > sparse feature in QEMU. > > It's needed for this series but yes, this ifdefery belongs in > a more central header. Maybe qemu/osdep.h > And it needs documentation and be a separate patch. Agree, Thank Michael's explanation, better to doing this in a separate patch series. > > > > > > > +typedef unsigned QEMU_BITWISE QemuMmapFlags; > > > + > > > /* RAM is pre-allocated and passed into qemu_ram_alloc_from_ptr */ > > > -#define RAM_PREALLOC (1 << 0) > > > +#define RAM_PREALLOC ((QEMU_FORCE QemuMmapFlags) (1 << 0)) > > > > > > /* RAM is mmap-ed with MAP_SHARED */ > > > -#define RAM_SHARED (1 << 1) > > > +#define RAM_SHARED ((QEMU_FORCE QemuMmapFlags) (1 << 1)) > > > > > > /* Only a portion of RAM (used_length) is actually used, and migrated. > > > * This used_length size can change across reboots. > > > */ > > > -#define RAM_RESIZEABLE (1 << 2) > > > +#define RAM_RESIZEABLE ((QEMU_FORCE QemuMmapFlags) (1 << 2)) > > > > > > /* UFFDIO_ZEROPAGE is available on this RAMBlock to atomically > > > * zero the page and wake waiting processes. > > > * (Set during postcopy) > > > */ > > > -#define RAM_UF_ZEROPAGE (1 << 3) > > > +#define RAM_UF_ZEROPAGE ((QEMU_FORCE QemuMmapFlags) (1 << 3)) > > > > > > /* RAM can be migrated */ > > > -#define RAM_MIGRATABLE (1 << 4) > > > +#define RAM_MIGRATABLE ((QEMU_FORCE QemuMmapFlags) (1 << 4)) > > > > > > /* RAM is a persistent kind memory */ > > > -#define RAM_PMEM (1 << 5) > > > +#define RAM_PMEM ((QEMU_FORCE QemuMmapFlags) (1 << 5)) > > > > > > static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn, > > > IOMMUNotifierFlag flags, > > > diff --git a/include/qemu/mmap-alloc.h b/include/qemu/mmap-alloc.h > > > index 50385e3..6fe6ed4 100644 > > > --- a/include/qemu/mmap-alloc.h > > > +++ b/include/qemu/mmap-alloc.h > > > @@ -7,7 +7,24 @@ size_t qemu_fd_getpagesize(int fd); > > > > > > size_t qemu_mempath_getpagesize(const char *mem_path); > > > > > > -void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared); > > > +/** > > > + * qemu_ram_mmap: mmap the specified file or device. > > > + * > > > + * Parameters: > > > + * @fd: the file or the device to mmap > > > + * @size: the number of bytes to be mmaped > > > + * @align: if not zero, specify the alignment of the starting mapping address; > > > + * otherwise, the alignment in use will be determined by QEMU. > > > + * @flags: specifies additional properties of the mapping, which can be one or > > > + * bit-or of following values > > > + * - RAM_SHARED: mmap with MAP_SHARED flag > > > + * Other bits are ignored. > > > + * > > > + * Return: > > > + * On success, return a pointer to the mapped area. > > > + * On failure, return MAP_FAILED. > > > + */ > > > +void *qemu_ram_mmap(int fd, size_t size, size_t align, uint32_t flags); > > > > > > void qemu_ram_munmap(void *ptr, size_t size); > > > > > > diff --git a/util/mmap-alloc.c b/util/mmap-alloc.c > > > index fd329ec..8f0a740 100644 > > > --- a/util/mmap-alloc.c > > > +++ b/util/mmap-alloc.c > > > @@ -13,6 +13,7 @@ > > > #include "qemu/osdep.h" > > > #include "qemu/mmap-alloc.h" > > > #include "qemu/host-utils.h" > > > +#include "exec/memory.h" > > > > > > #define HUGETLBFS_MAGIC 0x958458f6 > > > > > > @@ -75,7 +76,7 @@ size_t qemu_mempath_getpagesize(const char *mem_path) > > > return getpagesize(); > > > } > > > > > > -void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) > > > +void *qemu_ram_mmap(int fd, size_t size, size_t align, uint32_t flags) > > > { > > > /* > > > * Note: this always allocates at least one extra page of virtual address > > > @@ -92,11 +93,12 @@ void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) > > > * anonymous memory is OK. > > > */ > > > int anonfd = fd == -1 || qemu_fd_getpagesize(fd) == getpagesize() ? -1 : fd; > > > - int flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; > > > - void *ptr = mmap(0, total, PROT_NONE, flags | MAP_PRIVATE, anonfd, 0); > > > + int mmap_flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; > > > + void *ptr = mmap(0, total, PROT_NONE, mmap_flags | MAP_PRIVATE, anonfd, 0); > > > #else > > > void *ptr = mmap(0, total, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); > > > #endif > > > + bool shared = flags & RAM_SHARED; > > > size_t offset; > > > void *ptr1; > > > > > > diff --git a/util/oslib-posix.c b/util/oslib-posix.c > > > index fbd0dc8..75a0171 100644 > > > --- a/util/oslib-posix.c > > > +++ b/util/oslib-posix.c > > > @@ -54,6 +54,7 @@ > > > #endif > > > > > > #include "qemu/mmap-alloc.h" > > > +#include "exec/memory.h" > > > > > > #ifdef CONFIG_DEBUG_STACK_USAGE > > > #include "qemu/error-report.h" > > > @@ -203,7 +204,13 @@ void *qemu_memalign(size_t alignment, size_t size) > > > void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment, bool shared) > > > { > > > size_t align = QEMU_VMALLOC_ALIGN; > > > - void *ptr = qemu_ram_mmap(-1, size, align, shared); > > > + uint32_t flags = 0; > > > + void *ptr; > > > + > > > + if (shared) { > > > + flags = RAM_SHARED; > > > + } > > > + ptr = qemu_ram_mmap(-1, size, align, flags); > > > > > > if (ptr == MAP_FAILED) { > > > return NULL; > > > -- > > > 2.7.4 > > > > > > > > > > -- > > Eduardo
On Tue, Jan 15, 2019 at 10:39:14AM +0800, Yi Zhang wrote: > > It's needed for this series but yes, this ifdefery belongs in > > a more central header. Maybe qemu/osdep.h > > And it needs documentation and be a separate patch. > Agree, Thank Michael's explanation, better to doing this in a separate > patch series. Separate patch, does not have to be a separate series.
diff --git a/exec.c b/exec.c index bb6170d..e92a7da 100644 --- a/exec.c +++ b/exec.c @@ -1810,6 +1810,7 @@ static void *file_ram_alloc(RAMBlock *block, ram_addr_t memory, int fd, bool truncate, + uint32_t flags, Error **errp) { void *area; @@ -1859,8 +1860,7 @@ static void *file_ram_alloc(RAMBlock *block, perror("ftruncate"); } - area = qemu_ram_mmap(fd, memory, block->mr->align, - block->flags & RAM_SHARED); + area = qemu_ram_mmap(fd, memory, block->mr->align, flags); if (area == MAP_FAILED) { error_setg_errno(errp, errno, "unable to map backing store for guest RAM"); @@ -2279,7 +2279,8 @@ RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr, new_block->used_length = size; new_block->max_length = size; new_block->flags = ram_flags; - new_block->host = file_ram_alloc(new_block, size, fd, !file_size, errp); + new_block->host = file_ram_alloc(new_block, size, fd, !file_size, + ram_flags, errp); if (!new_block->host) { g_free(new_block); return NULL; diff --git a/include/exec/memory.h b/include/exec/memory.h index 667466b..6e30c23 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -103,28 +103,38 @@ struct IOMMUNotifier { }; typedef struct IOMMUNotifier IOMMUNotifier; +#ifdef __CHECKER__ +#define QEMU_BITWISE __attribute__((bitwise)) +#define QEMU_FORCE __attribute__((force)) +#else +#define QEMU_BITWISE +#define QEMU_FORCE +#endif + +typedef unsigned QEMU_BITWISE QemuMmapFlags; + /* RAM is pre-allocated and passed into qemu_ram_alloc_from_ptr */ -#define RAM_PREALLOC (1 << 0) +#define RAM_PREALLOC ((QEMU_FORCE QemuMmapFlags) (1 << 0)) /* RAM is mmap-ed with MAP_SHARED */ -#define RAM_SHARED (1 << 1) +#define RAM_SHARED ((QEMU_FORCE QemuMmapFlags) (1 << 1)) /* Only a portion of RAM (used_length) is actually used, and migrated. * This used_length size can change across reboots. */ -#define RAM_RESIZEABLE (1 << 2) +#define RAM_RESIZEABLE ((QEMU_FORCE QemuMmapFlags) (1 << 2)) /* UFFDIO_ZEROPAGE is available on this RAMBlock to atomically * zero the page and wake waiting processes. * (Set during postcopy) */ -#define RAM_UF_ZEROPAGE (1 << 3) +#define RAM_UF_ZEROPAGE ((QEMU_FORCE QemuMmapFlags) (1 << 3)) /* RAM can be migrated */ -#define RAM_MIGRATABLE (1 << 4) +#define RAM_MIGRATABLE ((QEMU_FORCE QemuMmapFlags) (1 << 4)) /* RAM is a persistent kind memory */ -#define RAM_PMEM (1 << 5) +#define RAM_PMEM ((QEMU_FORCE QemuMmapFlags) (1 << 5)) static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn, IOMMUNotifierFlag flags, diff --git a/include/qemu/mmap-alloc.h b/include/qemu/mmap-alloc.h index 50385e3..6fe6ed4 100644 --- a/include/qemu/mmap-alloc.h +++ b/include/qemu/mmap-alloc.h @@ -7,7 +7,24 @@ size_t qemu_fd_getpagesize(int fd); size_t qemu_mempath_getpagesize(const char *mem_path); -void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared); +/** + * qemu_ram_mmap: mmap the specified file or device. + * + * Parameters: + * @fd: the file or the device to mmap + * @size: the number of bytes to be mmaped + * @align: if not zero, specify the alignment of the starting mapping address; + * otherwise, the alignment in use will be determined by QEMU. + * @flags: specifies additional properties of the mapping, which can be one or + * bit-or of following values + * - RAM_SHARED: mmap with MAP_SHARED flag + * Other bits are ignored. + * + * Return: + * On success, return a pointer to the mapped area. + * On failure, return MAP_FAILED. + */ +void *qemu_ram_mmap(int fd, size_t size, size_t align, uint32_t flags); void qemu_ram_munmap(void *ptr, size_t size); diff --git a/util/mmap-alloc.c b/util/mmap-alloc.c index fd329ec..8f0a740 100644 --- a/util/mmap-alloc.c +++ b/util/mmap-alloc.c @@ -13,6 +13,7 @@ #include "qemu/osdep.h" #include "qemu/mmap-alloc.h" #include "qemu/host-utils.h" +#include "exec/memory.h" #define HUGETLBFS_MAGIC 0x958458f6 @@ -75,7 +76,7 @@ size_t qemu_mempath_getpagesize(const char *mem_path) return getpagesize(); } -void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) +void *qemu_ram_mmap(int fd, size_t size, size_t align, uint32_t flags) { /* * Note: this always allocates at least one extra page of virtual address @@ -92,11 +93,12 @@ void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared) * anonymous memory is OK. */ int anonfd = fd == -1 || qemu_fd_getpagesize(fd) == getpagesize() ? -1 : fd; - int flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; - void *ptr = mmap(0, total, PROT_NONE, flags | MAP_PRIVATE, anonfd, 0); + int mmap_flags = anonfd == -1 ? MAP_ANONYMOUS : MAP_NORESERVE; + void *ptr = mmap(0, total, PROT_NONE, mmap_flags | MAP_PRIVATE, anonfd, 0); #else void *ptr = mmap(0, total, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); #endif + bool shared = flags & RAM_SHARED; size_t offset; void *ptr1; diff --git a/util/oslib-posix.c b/util/oslib-posix.c index fbd0dc8..75a0171 100644 --- a/util/oslib-posix.c +++ b/util/oslib-posix.c @@ -54,6 +54,7 @@ #endif #include "qemu/mmap-alloc.h" +#include "exec/memory.h" #ifdef CONFIG_DEBUG_STACK_USAGE #include "qemu/error-report.h" @@ -203,7 +204,13 @@ void *qemu_memalign(size_t alignment, size_t size) void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment, bool shared) { size_t align = QEMU_VMALLOC_ALIGN; - void *ptr = qemu_ram_mmap(-1, size, align, shared); + uint32_t flags = 0; + void *ptr; + + if (shared) { + flags = RAM_SHARED; + } + ptr = qemu_ram_mmap(-1, size, align, flags); if (ptr == MAP_FAILED) { return NULL;