search for: next_zero

...il cleanly. OK, thanks. >> +static void convert_bmap_to_chunks(struct virtio_balloon *vb, >> + struct virtqueue *vq, >> + unsigned long *bmap, >> + unsigned long pfn_start, >> + unsigned long size) >> +{ >> + unsigned long next_one, next_zero, pos = 0; >> + u64 chunk_base_addr; >> + u32 chunk_size; >> + >> + while (pos < size) { >> + next_one = find_next_bit(bmap, size, pos); >> + /* >> + * No "1" bit found, which means that there is no pfn >> + * recorded in the rest of...

...ay. I'll send a patch to at least fail cleanly. > +static void convert_bmap_to_chunks(struct virtio_balloon *vb, > + struct virtqueue *vq, > + unsigned long *bmap, > + unsigned long pfn_start, > + unsigned long size) > +{ > + unsigned long next_one, next_zero, pos = 0; > + u64 chunk_base_addr; > + u32 chunk_size; > + > + while (pos < size) { > + next_one = find_next_bit(bmap, size, pos); > + /* > + * No "1" bit found, which means that there is no pfn > + * recorded in the rest of this bmap. > + */ > +...

...ay. I'll send a patch to at least fail cleanly. > +static void convert_bmap_to_chunks(struct virtio_balloon *vb, > + struct virtqueue *vq, > + unsigned long *bmap, > + unsigned long pfn_start, > + unsigned long size) > +{ > + unsigned long next_one, next_zero, pos = 0; > + u64 chunk_base_addr; > + u32 chunk_size; > + > + while (pos < size) { > + next_one = find_next_bit(bmap, size, pos); > + /* > + * No "1" bit found, which means that there is no pfn > + * recorded in the rest of this bmap. > + */ > +...

...); + if (chunk_num == VIRTIO_BALLOON_MAX_PAGE_CHUNKS) + send_page_chunks(vb, vq); +} + +static void convert_bmap_to_chunks(struct virtio_balloon *vb, + struct virtqueue *vq, + unsigned long *bmap, + unsigned long pfn_start, + unsigned long size) +{ + unsigned long next_one, next_zero, chunk_size, pos = 0; + + while (pos < size) { + next_one = find_next_bit(bmap, size, pos); + /* + * No "1" bit found, which means that there is no pfn + * recorded in the rest of this bmap. + */ + if (next_one == size) + break; + next_zero = find_next_zero_bit(bmap, size,...

...KS) > + send_page_chunks(vb, vq); > +} > + > +static void convert_bmap_to_chunks(struct virtio_balloon *vb, > + struct virtqueue *vq, > + unsigned long *bmap, > + unsigned long pfn_start, > + unsigned long size) > +{ > + unsigned long next_one, next_zero, chunk_size, pos = 0; > + > + while (pos < size) { > + next_one = find_next_bit(bmap, size, pos); > + /* > + * No "1" bit found, which means that there is no pfn > + * recorded in the rest of this bmap. > + */ > + if (next_one == size) > + break; &...

...KS) > + send_page_chunks(vb, vq); > +} > + > +static void convert_bmap_to_chunks(struct virtio_balloon *vb, > + struct virtqueue *vq, > + unsigned long *bmap, > + unsigned long pfn_start, > + unsigned long size) > +{ > + unsigned long next_one, next_zero, chunk_size, pos = 0; > + > + while (pos < size) { > + next_one = find_next_bit(bmap, size, pos); > + /* > + * No "1" bit found, which means that there is no pfn > + * recorded in the rest of this bmap. > + */ > + if (next_one == size) > + break; &...

...m += 1; + if (*num == VIRTIO_BALLOON_MAX_PAGE_CHUNKS) + send_page_chunks(vb, vq); +} + +static void convert_bmap_to_chunks(struct virtio_balloon *vb, + struct virtqueue *vq, + unsigned long *bmap, + unsigned long pfn_start, + unsigned long size) +{ + unsigned long next_one, next_zero, pos = 0; + u64 chunk_base_addr; + u32 chunk_size; + + while (pos < size) { + next_one = find_next_bit(bmap, size, pos); + /* + * No "1" bit found, which means that there is no pfn + * recorded in the rest of this bmap. + */ + if (next_one == size) + break; + next_zero = fi...

This patch series implements the follow two things: 1) Optimization of balloon page transfer: instead of transferring balloon pages to host one by one, the new mechanism transfers them in chunks. 2) A mechanism to report info of guest unused pages: the pages have been unused at some time between when host sent command and when guest reported them. Host uses that by tracking memory changes and

This patch series implements the follow two things: 1) Optimization of balloon page transfer: instead of transferring balloon pages to host one by one, the new mechanism transfers them in chunks. 2) A mechanism to report info of guest unused pages: the pages have been unused at some time between when host sent command and when guest reported them. Host uses that by tracking memory changes and

..._LONG - size)); + if (tmp == 0UL) /* Are any bits set? */ + return result + size; /* Nope. */ +found_middle: + return result + __ffs(tmp); +} + +/* + * This implementation of find_{first,next}_zero_bit was stolen from + * Linus'' asm-alpha/bitops.h. + */ +static inline unsigned long +find_next_zero_bit(const unsigned long *addr, unsigned long size, + unsigned long offset) +{ + const unsigned long *p = addr + BITOP_WORD(offset); + unsigned long result = offset & ~(BITS_PER_LONG-1); + unsigned long tmp; + + if (offset >= size) + return size; + size -= result; + offset %= BITS_PER_LO...

This patch series enhances the existing virtio-balloon with the following new features: 1) fast ballooning: transfer ballooned pages between the guest and host in chunks, instead of one by one; and 2) cmdq: a new virtqueue to send commands between the device and driver. Currently, it supports commands to report memory stats (replace the old statq mechanism) and report guest unused pages. Liang Li

This patch series enhances the existing virtio-balloon with the following new features: 1) fast ballooning: transfer ballooned pages between the guest and host in chunks, instead of one by one; and 2) cmdq: a new virtqueue to send commands between the device and driver. Currently, it supports commands to report memory stats (replace the old statq mechanism) and report guest unused pages. Liang Li

...return b_conn->b->can_zero (b_conn->b, b_conn->conn); } +static int +next_can_extents (void *nxdata) +{ + struct b_conn *b_conn = nxdata; + return b_conn->b->can_extents (b_conn->b, b_conn->conn); +} + static int next_can_fua (void *nxdata) { @@ -364,6 +371,16 @@ next_zero (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, return b_conn->b->zero (b_conn->b, b_conn->conn, count, offset, flags, err); } +static int +next_extents (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, + size_t *nr_extents, struct nbdkit...

...+next_trim (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags) { struct b_conn *b_conn = nxdata; - return b_conn->b->trim (b_conn->b, b_conn->conn, count, offset, 0); + return b_conn->b->trim (b_conn->b, b_conn->conn, count, offset, flags); } static int -next_zero (void *nxdata, uint32_t count, uint64_t offset, int may_trim) +next_zero (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags) { struct b_conn *b_conn = nxdata; - uint32_t f = 0; - - if (may_trim) - f |= NBDKIT_FLAG_MAY_TRIM; - - return b_conn->b->zero (b_conn->b, b_con...

...kend *b_next = nxdata; - return backend_flush (b_next, flags, err); -} - -static int -next_trim (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, - int *err) -{ - struct backend *b_next = nxdata; - return backend_trim (b_next, count, offset, flags, err); -} - -static int -next_zero (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, - int *err) -{ - struct backend *b_next = nxdata; - return backend_zero (b_next, count, offset, flags, err); -} - -static int -next_extents (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, - stru...

...return b_conn->b->can_zero (b_conn->b, b_conn->conn); } +static int +next_can_extents (void *nxdata) +{ + struct b_conn *b_conn = nxdata; + return b_conn->b->can_extents (b_conn->b, b_conn->conn); +} + static int next_can_fua (void *nxdata) { @@ -364,6 +371,16 @@ next_zero (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, return b_conn->b->zero (b_conn->b, b_conn->conn, count, offset, flags, err); } +static int +next_extents (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, + struct nbdkit_extents_map *extent...

...return b_conn->b->can_zero (b_conn->b, b_conn->conn); } +static int +next_can_extents (void *nxdata) +{ + struct b_conn *b_conn = nxdata; + return b_conn->b->can_extents (b_conn->b, b_conn->conn); +} + static int next_can_fua (void *nxdata) { @@ -364,6 +371,16 @@ next_zero (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, return b_conn->b->zero (b_conn->b, b_conn->conn, count, offset, flags, err); } +static int +next_extents (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, + struct nbdkit_extents_map *extent...

Another couple things I noticed that are worth improving, but aren't strictly related to implementing fast zero support. Eric Blake (2): server: Assert sane error responses nozero: More efficient FUA handling filters/nozero/nozero.c | 17 +++++++++++-- server/filters.c | 56 +++++++++++++++++++++++++++++++++-------- server/protocol.c | 32 +++++++++++++++++------ 3 files

...return b_conn->b->can_zero (b_conn->b, b_conn->conn); } +static int +next_can_extents (void *nxdata) +{ + struct b_conn *b_conn = nxdata; + return b_conn->b->can_extents (b_conn->b, b_conn->conn); +} + static int next_can_fua (void *nxdata) { @@ -364,6 +371,15 @@ next_zero (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, return b_conn->b->zero (b_conn->b, b_conn->conn, count, offset, flags, err); } +static int +next_extents (void *nxdata, uint32_t count, uint64_t offset, uint32_t flags, + struct nbdkit_extents *extents, i...

This tentative commit implements extents/can_extents, roughly as discussed in the previous thread here: https://www.redhat.com/archives/libguestfs/2019-March/msg00017.html I can't say that I'm a big fan of having the plugin allocate an extents array. There are no other plugin callbacks currently where we require the plugin to allocate complex data structures (or indeed do any allocation