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@@ -66,7 +66,7 @@ At mount time, the two directories given as mount options "lowerdir" and
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"upperdir" are combined into a merged directory:
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"upperdir" are combined into a merged directory:
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mount -t overlay overlay -olowerdir=/lower,upperdir=/upper,\
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mount -t overlay overlay -olowerdir=/lower,upperdir=/upper,\
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-workdir=/work /merged
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+ workdir=/work /merged
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The "workdir" needs to be an empty directory on the same filesystem
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The "workdir" needs to be an empty directory on the same filesystem
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as upperdir.
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as upperdir.
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@@ -118,6 +118,7 @@ programs.
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seek offsets are assigned sequentially when the directories are read.
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seek offsets are assigned sequentially when the directories are read.
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Thus if
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Thus if
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+
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- read part of a directory
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- read part of a directory
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- remember an offset, and close the directory
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- remember an offset, and close the directory
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- re-open the directory some time later
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- re-open the directory some time later
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@@ -137,12 +138,12 @@ When renaming a directory that is on the lower layer or merged (i.e. the
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directory was not created on the upper layer to start with) overlayfs can
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directory was not created on the upper layer to start with) overlayfs can
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handle it in two different ways:
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handle it in two different ways:
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-1) return EXDEV error: this error is returned by rename(2) when trying to
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+1. return EXDEV error: this error is returned by rename(2) when trying to
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move a file or directory across filesystem boundaries. Hence
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move a file or directory across filesystem boundaries. Hence
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applications are usually prepared to hande this error (mv(1) for example
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applications are usually prepared to hande this error (mv(1) for example
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recursively copies the directory tree). This is the default behavior.
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recursively copies the directory tree). This is the default behavior.
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-2) If the "redirect_dir" feature is enabled, then the directory will be
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+2. If the "redirect_dir" feature is enabled, then the directory will be
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copied up (but not the contents). Then the "trusted.overlay.redirect"
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copied up (but not the contents). Then the "trusted.overlay.redirect"
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extended attribute is set to the path of the original location from the
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extended attribute is set to the path of the original location from the
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root of the overlay. Finally the directory is moved to the new
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root of the overlay. Finally the directory is moved to the new
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